Messages in AirborneWindEnergy group.                       AWES3239to3288 Page 45 of 79.

Group: AirborneWindEnergy Message: 3239 From: dave santos Date: 3/22/2011
Subject: Re: Single-Tether Multi-AutoGyro (SkyMill-MultiTurbine Hybrid)

Group: AirborneWindEnergy Message: 3240 From: dave santos Date: 3/23/2011
Subject: Brian Germain/// Re: valved parafoils for airborne wind energy appli

Group: AirborneWindEnergy Message: 3241 From: Joe Faust Date: 3/24/2011
Subject: K1, K2, K3

Group: AirborneWindEnergy Message: 3242 From: Robert Copcutt Date: 3/24/2011
Subject: New development hub, Cambridge, UK.

Group: AirborneWindEnergy Message: 3243 From: dave santos Date: 3/24/2011
Subject: Spring 2011 European AWE Working Tour?

Group: AirborneWindEnergy Message: 3244 From: dave santos Date: 3/24/2011
Subject: Re: Quality of electricity

Group: AirborneWindEnergy Message: 3245 From: Joe Faust Date: 3/24/2011
Subject: Game: Kite-System Skydiving

Group: AirborneWindEnergy Message: 3246 From: Bob Stuart Date: 3/25/2011
Subject: Re: Game: Kite-System Skydiving

Group: AirborneWindEnergy Message: 3247 From: Bob Stuart Date: 3/25/2011
Subject: Re: Game: Kite-System Skydiving

Group: AirborneWindEnergy Message: 3248 From: Pierre Benhaiem Date: 3/25/2011
Subject: An article upon HAWP

Group: AirborneWindEnergy Message: 3249 From: Joe Faust Date: 3/25/2011
Subject: Re: Game: Kite-System Skydiving

Group: AirborneWindEnergy Message: 3250 From: dave santos Date: 3/25/2011
Subject: Re: Game: Kite-System Skydiving

Group: AirborneWindEnergy Message: 3251 From: christopher carlin Date: 3/25/2011
Subject: Re: Game: Kite-System Skydiving

Group: AirborneWindEnergy Message: 3252 From: dave santos Date: 3/26/2011
Subject: Re: Game: Kite-System Skydiving

Group: AirborneWindEnergy Message: 3253 From: Joe Faust Date: 3/26/2011
Subject: http://energykitesystems.net/ApplicationsKES/SkydivingByKS/4scenario

Group: AirborneWindEnergy Message: 3254 From: dave santos Date: 3/26/2011
Subject: Winch-Tow as an Aviation Basis

Group: AirborneWindEnergy Message: 3255 From: davednorth Date: 3/26/2011
Subject: Re: An article upon HAWP

Group: AirborneWindEnergy Message: 3256 From: Joe Faust Date: 3/26/2011
Subject: Re: An article upon HAWP

Group: AirborneWindEnergy Message: 3257 From: Joe Faust Date: 3/26/2011
Subject: Wensman, Robert

Group: AirborneWindEnergy Message: 3258 From: dave santos Date: 3/26/2011
Subject: Re: An article upon HAWP (FAA/ICAO hurdles)

Group: AirborneWindEnergy Message: 3259 From: dave santos Date: 3/26/2011
Subject: Fw: Toy Looper AWECS

Group: AirborneWindEnergy Message: 3260 From: christopher carlin Date: 3/27/2011
Subject: Re: An article upon HAWP

Group: AirborneWindEnergy Message: 3261 From: Pierre Benhaiem Date: 3/28/2011
Subject: Re: An article upon HAWP

Group: AirborneWindEnergy Message: 3262 From: Joe Faust Date: 3/28/2011
Subject: OPTEC items

Group: AirborneWindEnergy Message: 3263 From: Bob Stuart Date: 3/28/2011
Subject: Re: An article upon HAWP

Group: AirborneWindEnergy Message: 3264 From: dave santos Date: 3/28/2011
Subject: Shunting KitePlane AWECS Demo

Group: AirborneWindEnergy Message: 3265 From: davednorth Date: 3/28/2011
Subject: Re: An article upon HAWP (and more on Airspace Regulations)

Group: AirborneWindEnergy Message: 3266 From: Joe Faust Date: 3/28/2011
Subject: Re: Shunting KitePlane AWECS Demo

Group: AirborneWindEnergy Message: 3267 From: dave santos Date: 3/30/2011
Subject: Please Forward to Ben Harder ("Start-ups are devising kites..." Mar2

Group: AirborneWindEnergy Message: 3268 From: dave santos Date: 3/30/2011
Subject: Popoular Mechanics features AWE Consortium (online link)

Group: AirborneWindEnergy Message: 3269 From: Joe Faust Date: 3/30/2011
Subject: AWEA conference wants diversity without AWE, apparently ...

Group: AirborneWindEnergy Message: 3270 From: Joe Faust Date: 3/30/2011
Subject: Tether cousins: Space elevator

Group: AirborneWindEnergy Message: 3271 From: Doug Date: 3/31/2011
Subject: Re: AWEA conference wants diversity without AWE, apparently ...

Group: AirborneWindEnergy Message: 3272 From: harry valentine Date: 3/31/2011
Subject: Re: AWEA conference wants diversity without AWE, apparently ...

Group: AirborneWindEnergy Message: 3273 From: dave santos Date: 3/31/2011
Subject: Phonon Power? (Reply to Doug)

Group: AirborneWindEnergy Message: 3274 From: Theo Schmidt Date: 3/31/2011
Subject: Re: AWEA conference wants diversity without AWE, apparently ...

Group: AirborneWindEnergy Message: 3275 From: Doug Date: 3/31/2011
Subject: Re: Tether cousins: Space elevator

Group: AirborneWindEnergy Message: 3276 From: dave santos Date: 3/31/2011
Subject: The Kite as Philosopher's Stone

Group: AirborneWindEnergy Message: 3277 From: Doug Date: 4/1/2011
Subject: Re: AWEA conference wants diversity without AWE, apparently ...

Group: AirborneWindEnergy Message: 3278 From: dave santos Date: 4/1/2011
Subject: Power Plant Direct Staffing Requirements

Group: AirborneWindEnergy Message: 3279 From: dave santos Date: 4/3/2011
Subject: Isotropic Kite Demo (Scale "Large-Array" Model)

Group: AirborneWindEnergy Message: 3280 From: simon_0987 Date: 4/4/2011
Subject: In which countries can you fly your kites legally?

Group: AirborneWindEnergy Message: 3281 From: Pierre Benhaiem Date: 4/4/2011
Subject: Re: In which countries can you fly your kites legally?

Group: AirborneWindEnergy Message: 3282 From: Pierre Benhaiem Date: 4/4/2011
Subject: Makani M1

Group: AirborneWindEnergy Message: 3283 From: Pierre BENHAIEM Date: 4/4/2011
Subject: Re: Makani M1

Group: AirborneWindEnergy Message: 3284 From: dave santos Date: 4/4/2011
Subject: Re: Makani M1

Group: AirborneWindEnergy Message: 3285 From: dave santos Date: 4/4/2011
Subject: Joby Energy Mishap Report for the Incident Case-Base

Group: AirborneWindEnergy Message: 3286 From: dave santos Date: 4/4/2011
Subject: Re: Makani M1

Group: AirborneWindEnergy Message: 3287 From: Pierre BENHAIEM Date: 4/4/2011
Subject: Re: Makani M1

Group: AirborneWindEnergy Message: 3288 From: Pierre BENHAIEM Date: 4/4/2011
Subject: Re: Makani M1




Group: AirborneWindEnergy Message: 3239 From: dave santos Date: 3/22/2011
Subject: Re: Single-Tether Multi-AutoGyro (SkyMill-MultiTurbine Hybrid)
I've reviewed Doug's patent & don't see that it covers multi-rotors that merely pull on a gangline rather than torquing a driveshaft. It also does not address running rotors up & down on carriages.
 
The idea of coaxial rotors is centuries old, with a default driveshaft. Does one of Gaylord's patents cover multirotors on an axial line?
 
It would be funny if Doug had blocking patent on SkyMill's natural evolution ;^)

Group: AirborneWindEnergy Message: 3240 From: dave santos Date: 3/23/2011
Subject: Brian Germain/// Re: valved parafoils for airborne wind energy appli
Master parachute & paraglider designer Brian Germain is another top new talent in Kite Energy circles. Over a period of decades he has refined valved parafoils well beyond where Jalbert left off. Brian sees them as a top AWE contender as they have strong collapse resistance like an LEI kite, but a higher L/D, lower capital cost, lower maintenance, longer life, lighter weight, & so on. An valved pararfoil is still a true ram-air device that stiffens progressively with airspeed. Brian also instantly sees the power of hoisting packed foils aloft & popping them like parachutes & maybe incorporating small blowers in large working foils to perfect them further, after all, LEI's require pre-inflation & regular pumping up. 
 
Brian is happy to join AWEIA's founder circle & volunteers to be an informal Washington DC based "lobbyist" for the infant AWE Industry, especially to perform critical technical liaison with FAA & NASA HQs. He is also a long time volunteer at the Smithsonian Air & Space Museum & regualrly presents to the Smithsonian public on skydiving tech.* Brian has also designed & manufactured sport kites, sailed, & piloted several aircraft types. Brian is a nice addition to the key skydiving-AWE connection (Andy Keech, Jerry Coleman, etc.) & is also really excited about aloft-stationed piloting of giant AWECS & the future of wind-powered skydiving.
 
*  Note: The Air & Space Museum is planning a new kite exhibit coincidental with the World Kite Museum's plans for a Kite Energy exhibit & collaboration is proposed.
 
Two of Brian's books-
 
The Parachute and its Pilot: The ultimate guide for the ram air aviator
 
Vertical Journey: The art of new age skydiving

Brian's Radio Show: 
Safety First with Brian Germain
 
 
 

Group: AirborneWindEnergy Message: 3241 From: Joe Faust Date: 3/24/2011
Subject: K1, K2, K3

Edits, corrections, additions ... are invited from all toward glossary items.

For example, this mornings status on K1, K2, K3      are open for modification:

K1  Kiting giving birth to flight from early ages to Wright Brothers' kiting.
 
K2  Jalbert, Allison, Wanner, Rogallo, Barish, Paresev, towed manned kiting,  traction sports, kiting festivals,  free-flight manned kiting (i.e. governable parachuting, skydiving, hang gliding), competitions, parties, tricks, art, celebrations, ... Authors: Will Yolen (IKA and Worldwide Friends through Kiteflying), Robert Ingraham, Joe Faust (K.I.T.E.S.A., S-SA, L&S, HGW), Dan Poynter (HG), Dave Santos, Dave Culp, Valerie Govig, and more...
 
K3     ~~~ AWE Era ~~~   The space race Sputnik-(1957)-charged introduced a synergy that resulted in increased manned kiting activity by NASA and associated companies and individuals, including hgh-speed moving moorings of tethered lifting bodies. This brought in a run of patents over the Wanner wing, Rogallo wing, Barish sailwing, Jalbert parafoil, and many versions of  what was then termed paraglider which wrapped flexible sail over frames (unlike the later use of the term paraglider). The free-flight governable parachutes increased in importance. The severe kiting in the Paresev program included release-for-glide weight-shift control (move payload mass relative to attitude of wing). Such kiting gave impetus to expanding uses of large kites, both with moving moorings and free-flight kites. Children of such investments and experience may be seen in the surge of hang gliding, traction-kiting sports, the 1970s AWECS bump, and even much of 2000s professional AWECS race. It may be said that a huge new golden age of kiting K2 was birthed by the communications of Domina C. Jalbert and Francis M. Rogallo moved along by political pressures and competitions punctuated with the need for freedom expressed in recreational manned kiting found in Igor Bensen, aqua-kiting, hang gliding, and gliding sky-diving. It is suspected that K2 has been blossoming to be a diamond Age of Tethered Aviation and Kite Energy that will be a deserving winner of the K3 name; founders of K3 will be viewable in part in the AWEIA international's coming Founder's Circle collection of over 600 persons,  certainly less than the full community that will expand to tens of thousands.    The neat thing is that K1 and K2 remain alive and well, even while K3 is being nursed by centers in  Belgium, Ireland, England, Netherlands, Russia, China, USA, Nigeria, Germany, France, Mexico, Syria, France, and many other corners of earth...   Use kites to do special works including the making of useful stored energy or energy sent into energy-distribution systems:   K3 ~~AWE Era~~               M2776
Group: AirborneWindEnergy Message: 3242 From: Robert Copcutt Date: 3/24/2011
Subject: New development hub, Cambridge, UK.
Hi,

This forum is great for sharing ideas globally but we need more local
hubs where people can make real machines. I recently met a couple of
other people in Cambridge who share my enthusiasm for AWE so we are
going to seed a new local hub.

I have drawn up a rough proposal that I have posted at -
http://www.copcutt.me.uk/kite_energy.html

Some of the ideas are drawn from this forum and are therefore probably
open-source. Does anyone know of any patents we may clash with when
building this machine?

Thanks,

Robert.
Group: AirborneWindEnergy Message: 3243 From: dave santos Date: 3/24/2011
Subject: Spring 2011 European AWE Working Tour?
Is anyone planning to attend the Leuven conference (AWEC2011) also interested in extended group travel to include site visits to the major Kite Energy sites & teams across Europe? A group can share costs, planning, & better carry an interesting mix of kites & small AWECSs to demo or play with,  for a super productive working tour. A mix of camping, hotels, public transport, rental cars, & even bikes & boats is proposed. The territory covered might range from Scandinavia to Italy, with many top AWE & kite-tech contacts to visit. June is also a busy kite festival month with many wonderful options, like the Fano Festival. The tour might run from a couple of weeks up to a month & participants could choose to do just a part of it. Native EU host-guides would be especially helpful & could defray expenses by shepherding the foreigners.
 
Please reply to this post or contact me directly if interested...
 
 
dave santos
KiteLab Group

Group: AirborneWindEnergy Message: 3244 From: dave santos Date: 3/24/2011
Subject: Re: Quality of electricity
Pierre,
 
We now have extensive experimental data to confirm what we used to guess about airborne power signatures. TUDelft's latest video (linked from Allister's blog below) shows a general research case of a moderately good wing going thru a reeling cycle. The animated power curve overlaid on the videogrammetry is very nice; adding airspeed, altitude, etc., will be a great pilot interface.
 
The cycling shown is roughly half-time power generating & half retracting, with about 3 times more power generated than retract consumes. This is not great, but will only get better, already matching what is expected of flygens in average wind. The half-time cycle suggests using two kites operating in opposed phase to provide ~continuous power, but the combined MTBF of the two kites inverse sums in such a configuration. so one would prefer many kite cells to average to a level plant output. 
 
One effect we are seeing in many of these spikey-looking data streams is electrical & sampling error noise (Rob posted the prettiest curves from LabView(R)). The kite itself is not such a spikey source, but a generator-motor has ripple & taking small samples out of phase with ripple makes for a noisy looking signal. So ignore the transients & just look at the overall trends.
 
KiteLab predicts optimal AWECS power cycles will have very brief frequent recovery phases, probably at the natural frequency of the flight pattern. Only a small amount of capacitance (including line range-of-motion) will then be required to level the output & airspace will be better utilized. In future systems, power out will also be able to track grid demand closely
 

Kite, airborne and high altitude wind energy blog

 
 
 

From: Pierre Benhaiem <pierre.benhaiem@orange.fr
 

Excepted for schemes like KiteGen carousel,the power of kites is not
regular when the (more powerful) crosswind configuration is used.Schemes
like reel-out and flygen are concerned,reel-out yet more because of
reel-in phase.So without smoothing devices or management of unities in a
farm the quality of produced electricity could be low.

Have existant simulations taken into account the quality of produced
electricity?

PierreB




Group: AirborneWindEnergy Message: 3245 From: Joe Faust Date: 3/24/2011
Subject: Game: Kite-System Skydiving

Game rules: 
Post a description of a kite system (KS) that gives a skydiver (SD) a skydive.
Post at most one distinct scenario per post in this thread. 

 The descriptions may gloss over fine details. 
Target is to generate at least 20 distinct scenarios. 
Cares about safety over each scenario could come sooner or later; but the game is closer to brainstorming than fine tuning.

Along the way, mentioning motivations for skydives will enrich the thread;
why skydive?   Why use kite systems to skydive?

Ready?  Have fun!  There are some business opportunities radiating from this game.

Group: AirborneWindEnergy Message: 3246 From: Bob Stuart Date: 3/25/2011
Subject: Re: Game: Kite-System Skydiving
Wouldn't the obvious thing be to just use a parafoil chute, and launch on a kite line?  Perhaps it would work best with a section of bungee cord and a safety release. A stack of parafoils would help you to get out of the slow air near the ground.

Bob

On 24-Mar-11, at 10:39 PM, Joe Faust wrote:


Group: AirborneWindEnergy Message: 3247 From: Bob Stuart Date: 3/25/2011
Subject: Re: Game: Kite-System Skydiving
P.S. - at the top end of the tether, the skydiver could attach a kite to aid line retrieval.  A complete separate 'chute might be carried so that the first one could be hooked to the line allowing a full skydive instead of just a rapid-descent mode.  

Bob

On 24-Mar-11, at 10:39 PM, Joe Faust wrote:


Group: AirborneWindEnergy Message: 3248 From: Pierre Benhaiem Date: 3/25/2011
Subject: An article upon HAWP

Interesting link from Stefano (KiteGen group) today: http://www.powergenworldwide.com/index/display/wire-news-display/1379964058.html

PierreB                                                                                      http://flygenkite.com  

Group: AirborneWindEnergy Message: 3249 From: Joe Faust Date: 3/25/2011
Subject: Re: Game: Kite-System Skydiving
Group: AirborneWindEnergy Message: 3250 From: dave santos Date: 3/25/2011
Subject: Re: Game: Kite-System Skydiving


Wind Powered Skydiving promises to be dirt cheap, but needs to fully reproduce the basic function of the Jump Plane to really be wildly popular: It must be a fast climb for multiple jumpers. Normal surface wind is not really enough to allow a jumper to launch with only a tether & their own canopy as a kite; that would require about 30knts for modern sport canopies. Wind powered aerotowing is a partial solution, but these modes do not favor free-fall, the essence of the sport. What's needed is a sort elevator or upward zip-line held up & powered by large kites maintained at altitude. At the top there needs to be a "sky terminal", likely a light weight platform where several jumpers can gather.
 
The simplest existing model is a traditional "kite messenger", a wind-powered line-climbing device. The skydiver might use her own chute to rise along the line, as the power requirement is eased, but it would be important not rub lines or chute together. A leader line might allow the jumper to work the chute clear of a main zip-line. The ultimate system is likely a kite-based AWE-driven gondola cableway to the sky, but it would be a considerable R&D project. Such a system would have many potential uses, even including regional transit.

Group: AirborneWindEnergy Message: 3251 From: christopher carlin Date: 3/25/2011
Subject: Re: Game: Kite-System Skydiving
How about slingshot launching the sky diver the way you do RC gliders. It would be an exciting ride.

Chris
On Mar 25, 2011, at 4:52 PM, dave santos wrote:


Group: AirborneWindEnergy Message: 3252 From: dave santos Date: 3/26/2011
Subject: Re: Game: Kite-System Skydiving
Yeah, a super fast tow similar to a bungee launch would be a great way to go. The jump plane could be kinda like a WWII troop glider, but far hotter, capable of being accelerated to several hundred miles an hour for a final ballistic climb phase. You want to be able to put eight jumpers at about 12,000ft to replicate an average DZ capability.
 
See next post [Winch Tow as an Aviation Basis] for a more general discussion.
 
 
 
Chris wrote- 
 
How about slingshot launching the sky diver the way you do RC gliders. It would be an exciting ride.


Group: AirborneWindEnergy Message: 3253 From: Joe Faust Date: 3/26/2011
Subject: http://energykitesystems.net/ApplicationsKES/SkydivingByKS/4scenario
Group: AirborneWindEnergy Message: 3254 From: dave santos Date: 3/26/2011
Subject: Winch-Tow as an Aviation Basis
The more we look at AWE-driven winch-towing of gliders the more it seems like a potential foundation for extensive fueless aviation. It works at all scales, from model to jumbo aviation.
 
Fast tow a L/D30 gliderliner to 10,000m & it will glide some 300km a hop. Repeating the tow XC (bounding mode) can go any distance. Aircraft could even be slingshot into the upper stratosphere for very fast ballistic XC travel. A simple mechanism is bow-string geometry where a short powerful fairly slow longitudinal tug on the "bowstring" creates high speed transverse travel. I have studied Wayne's hypersonic kite concept for feasibility & find that a tungsten cable could resist even orbital re-entry heat, although some sort of ceramic anti oxidation coating would be needed for long life. Nano tubes will be even better for extreme performance towing.
 
A future-tow key is a little airplane at the end of the tow rope to fly the tow rope for docking & back during retracts, sort of like the winged mid-air refueling pods. All sorts of variations would work; a major hub airport might have a continuous tow rope to launch transports at a high rate. Folks have already towed many gliders in gangs; the record is like nine at once & could be far higher. E-train-based ground towing is attractive. 
 
There are two main options in applying the AWE. We could power electric winch-towing as a separated utility, or direct power the winching with kites. E-flight aerotow would also have a place, but be fairly limited by the battery requirement.
 
coolIP
 
 

Group: AirborneWindEnergy Message: 3255 From: davednorth Date: 3/26/2011
Subject: Re: An article upon HAWP
This is a very good article by Max Bronstein. It should be read by all who are doing work in the AWE field. However, he failed to delve into the biggest near-term hurdle for AWE developers in the U.S.; FAA airspace regulations. Right now, even small-scale prototype development in AWE is basically locked up (prohibited) due to very restrictive airspace regulations (unless you are willing to break the law, which I'm sure some are doing). CFR 14 Part 101, which is not meant for commercial product development but only for hobbyist kite fliers, balloon fliers, and small hobby rockets, is the only reg that touches on tethered flight vehicles and it is extremely constraining for kite fliers (<150 ft w/o NOTAM, <500 ft. w/ NOTAM).

Some of us at NASA are starting a dialog with the FAA on the regulation issue. I would like to hear some opinions and potential approaches from you guys on adding to or changing the regulations. And please be realistic, we can't just go in and demand that the FAA immediately carve out large chunks of airspace for commercial AWE use. Not going to happen in the near term.

We are also trying to get a test site (or two) set up within NASA restricted airspace (Wallops and/or KSC) so that AWE developers will have a site with restricted airspace (outside of FAA jurisdiction) where you can go up to higher altitudes and not have to worry about breaking the law.

Regards,

Dave North

Group: AirborneWindEnergy Message: 3256 From: Joe Faust Date: 3/26/2011
Subject: Re: An article upon HAWP
A comment about the article:

Have your slant guards up.
The effort to form some unconventional acronyms are suspected to be a
means to keep a focus on SWP while avoiding bringing bridge to the
avalanche of all stakeholders into view for readers. Analyze the comment
about where the science is being done! Notice the uncommon fresh
absence of Makani and Joby while very much mention of SWP. Thre is
evidence in text that the author knew of EnergyKiteSystems where a
possible bridge and rub with the extensive KiteLab Group could have
spawned direct interview and contact. If I was PR for SWP, I might have
written the article with the slants involved. The mention of "cohorts"
is the nod to the huge body of people profoundly advancing AWECS. Such
an article along with the pointed Popular Mechanics slant, and some AWE
is moved forward, but so much hitch to just one star of our galaxy of
players may become a liability for the industry.
Group: AirborneWindEnergy Message: 3257 From: Joe Faust Date: 3/26/2011
Subject: Wensman, Robert

Welcome Swedish kite turbine thinker  Robert Wensman

http://robertwensman.wordpress.com/2011/03/26/the-kite-turbine/

http://robertwensman.wordpress.com/2010/03/27/drommen-om-drakturbinen/ 

==================

Introduction to us from SpiralAirfoi l that has been making steps toward kiting spiral kited or kite turbines of various rigidities from soft to very hard. Thanks, Dan Parker, for the lead to Robert Wensman.     Seems like a possible collaboration?

Group: AirborneWindEnergy Message: 3258 From: dave santos Date: 3/26/2011
Subject: Re: An article upon HAWP (FAA/ICAO hurdles)
DaveN,
 
The good news about existing FAA kite regs is the huge loophole for lean systems under 5lbs. The only strict requirement for a lightweight kite is to not operate in an unsafe fashion, which still requires expert judgment. Anyone able to design (& properly justify) safe remote experimental operations is in the clear. Its likely this loophole will close considerably as the NextGen Airspace overhaul occurs.
 
Given the safety, reliable dynamic similarity, & agile-engineering power of scale prototypes its a laugh to see AWE "dinosaurs" slowly struggle with oversized foundational science experiments. It is possible to legitimize scaled-up AWE R&D under cover of related approved activities like aero-tow. For those who understand how to use fully certificated aircraft & pilots in a convincingly safe manner, the AWE dimension remains outside of regulation. The downside of relying on just two NASA airspaces is that no AWE R&D player is based at those locations & NASA is surely qualified & obliged to enforce most of the same general safety culture & restrictions as the FAA. The key for real developers is to build up many years worth of  flight-test hours & limited demo-dates at NASA don't do that.
 
Below is the latest KiteLab/AWEIA regulatory framework document (paste-job messed up formatting), if anyone has input to add prior to a 1.0 version intended for AWEC2011,
 
daveS
 

DRAFT

Tethered-Aviation ConOps (TACO)

Focus on Experimental Airborne Wind Energy (AWE)

Proposed FAA Advisory Circular

Proposal for Action- ICAO Standards And Recommended Practices (SARPs)

 

Note to the TACO 7th Draft-
 
At the second Airborne Wind Energy (AWE) Conference (AWEC2010), the attending FAA official publicly called for the early industry to define the emerging aircraft types into the FAA's Category & Class system. For its part NASA informally tasked industry players with developing ConOps frameworks for AWE in the US National Airspace (NAS). The Airborne Wind Energy Industry Association (AWEIA) responded by initiating this report addressing requirements. KiteLab Group, an AWE R & D pioneer, volunteered to compile a master Tethered Aviation ConOps (TACO), in an open collaborative process. TACO is intended as an FAA Advisory Circular to inform aviation stakeholders of the issues. While AWE is the priority application of this ConOps, the full scope is TA as a whole. Not only are there exciting new kinds of TA, bit there is a vast pool of historic TA precedent & working models to apply to AWE operations.  T ethered or not, persistent acceptance-barriers exist to autonomous aviation in the US NAS (National AirSpace). The current FAA requirement for piloted systems will hold for some years.  Thus this early-stage TAConOps Draft is "pilot-centric", embracing the pilot's key stakeholder status, but also is forward-looking toward eventual flight autonomy (Appendix). As a major future energy technology, AWE has the potential to subsidize many of the dreams of aviation planners & general aviation. This document is intended to evolve & merge into the NextGen Airspace ConOps. The US (FAA) regulatory standard is expected to drive the international picture (ICAO, etc). Send corrections, additions, & comments to santos137@yahoo.com
Acronyms
(add definitions) AKA AOPA AMA AWE AWEIA AWEA ConOps FAA FARs ICAO NASA R&D SARPs TA TACO sUAS UAV
 
Executive Summary
 
Tethered Aviation is an old & important branch of Aeronautics, with a erostats, aerotowing , & kites as well-known examples. New tether-based flight systems under development will enhance conventional aviation capabilities, host infrastructure (ie. communications), spin-off industries, create recreation, & generate clean energy. This "New Aviation" requires the primary stakeholders, pilots, developers, regulatory bodies, & populations, to come together to resolve technical & social challenges & realize the great potential. For the immediate purpose of private R&D, the current system is not broke; change by small increments grows over time into major mature sectors.
 
Pilots are a key stakeholder, as primary users of airspace most exposed to flight risk. Following aviation norms & traditions, pilots will lead safe effective Tethered Aviation R&D, fill jobs in the new aviation industries  & ensure safe operations consistent with shared airspace. The aerospace industry tasked with designing systems that pilots accept & the FAA can certify as airworthy. Policy developers & decision makers, from the national to the local level, are another key stakeholder group. These aviation interests must reach concensus to convince extended stakeholders that TA enhances society as a "good neighbor". The TACO lays out a basis for them to help reach a public consensus regarding the best use of TA in the NAS.
Aviation Self-Regulation Principle
 
By tradition the FAA relies on all sectors of aviation, via its user & industry associations, to refine & promote best practice of members. Safe operations & responsible leadership by each sector allows the FAA to maximize resources & perform oversight with a light touch. 
 
The Airborne Wind Energy Industry Association (AWEIA) undertakes, as part of its formal mission, to perform the leadership role of self-regulation for AWE in particular, but also to serve specialized TA as a whole. This TACO is AWEIA's first step in coordinating member standards for safety & acting as the industry liason with the FAA & ICAO. AWEIA will petition the FAA for new Rulemaking following the example of the Experimental Aircraft Association (EAA) & FAA together creating the regulatory package for a new category of Light Sport Aviation. Similarly AWEIA will work within the ICAO framework to develop a core SARPs.
 
There are already urgent R&D safety issues AWEIA is addressing, such as obligatory sharing of safety-critical failure modes & mishap reporting. AWEIA is just one of several associations with overlapping interest in TA. AOPA & EAA have strong interests within the new sectors. The American Kiters Association (AKA) governs recreational & professional kite operations. The American Modelers Association (AMA) is responsible for safe hobbyist aviation. User associations in soaring & other sectors that commonly perform tethered operations also have stakeholder oversight roles. Key wind energy industry standards promoted by AWEA also apply to AWE operations.
 
TA Excise Taxes & User Fees
 
The new AWE  technology taps airspace as a source of vast energy. M ajor energy sources all pay excise taxes, with 5% of producer's selling price typical. Unlike excise taxes on extractive non-renewable energy sources which eventually run out, renewables generate revenue in perpetuity. Barriers to broad AWE societal stakeholder acceptance, like NIMBY (not-in-my-back-yard) forces, will tend to melt away before a rich new tax base that more than offsets any negatives.  Energy excise taxes often directly offset environmental downsides with mitigation measures. The average citizen who does not fly or own aircraft still shares a birthright to the airspace commons. An equitable AWE Excise Tax can make a huge contribution to basic social welfare & a new era of sustainable prosperity for all.
 
Airspace access is by tradition a Public Commons based on Freedom-of-the-Seas. There is already resistance by existing aviation stakeholders to allowing privatization of AirSpace as some venture-capital AWE stakeholders have proposed. Utility-scale AWE operations can contribute to shared airspace by paying Excise Taxes on energy extracted & maybe even special Airspace User Fees. Airspace User Fees is a toxic idea to existing aviation but makes sense for some of the new types of aviation.
 
The AWE industry can thus earn aviation stakeholder acceptance by subsidizing common airspace infrastructure benefiting all. AWE tax revenue can offset existing FAA costs, relieving the overall Federal budget, pay for NextGen infrastructure, guarantee liability performance, & fund publicly-shared AWE R & D. The early industry requires a phase-in period for taxes, so as to not choke off early investment & to promote initial growth. As significant mature AWE revenue-base develops, & airspace becomes widely impacted, the tax base can be tapped. Small-scale personal AWE operating at low altitudes should be exempted commercial taxes.
 
Insurability
 
Like all aviation, TA operations must carry Liability Insurance proportional to risk. Such insurance is currently unavailable from traditional providers & a special TA Liability Fund is needed to jumpstart liability coverage. Secondary coverage, like Hull Insurance, does not fall under this recommnedation. A wrongful death these days can cost some ten million USD. The insurability guaranteed by an excise endowed fund can ensure that a financially weak AWE player in a freak-accident (even an unknown failure-mode) event does not leave victims or families uncompensated.
FARs Category, Class, & Type Certifications for TA
The FAA tasks the AWE Industry (AWEC2010) with defining the profusion of TA designs & new Types into the FAA's Aircraft/Airman/Operations Category, Class, & Type System. As categories naturally grow by adding Classes, so special TA Classes are proposed to be defined within current Categories. Note that FARs are sometimes vague, confused,  & contradictory; no totally clean classification scheme is workable, only patchwork progress. NextGen FARs will improve classification by a major overhaul. There is traditional wiggle-room in the existing system, with many exceptions & options at the discretion of authorities, including classification under multiple categories & classes. Aviation is increasingly diverse & some new branches may become wholly new Categories. 
Just like any other aircraft, TA platforms can be classified by gross-weight & airspeed, by the same physics of "consequence". Weight & Speed (mass & velocity) are primary determinants of Class within a Category. In general higher mass/velocity Classes have Higher Consequence Failure-Modes & so require proportionally higher standards for equivalent safety (mortality to flight hours). Stall Speed is a key safety consideration, the lower the better, with the widest possible range of operation between max airspeed & stall speed.
 
Some  major Aircraft Categories- aircraft, rotorcraft, normal, utility, acrobatic, commuter, transport,  manned free balloon, glider, special, restricted, etc. As an example of how TA Class can apply across Categories, many given Types can be modified for aerotowing, with special restrictions accruing. Single/Multi-Engine Classes- Many TA applications have powered modes that naturally assign them to an Engine Class within a Category. The trade-off of getting improved reliability from multi engines is a higher standard of Pilot training & engineering design required.
Examples of new Classes created- Tethered-Aerobatic, Tethered-Single-Engine, Tethered-Multi-Engine, Tethered-Normal, Utility, Sport, Ultralight, Moored-Balloon, Aero-Towed Glider, Tethered Rotorcraft.
The tether is a significant flying object in itself. Far-flung tether geometry is a unique TA feature to account for, but has useful similarity to standard geometry flight trajectories & operations like skydiving. Electrically Conductive Tethers require special standards addressing all safety issues. Aircraft joined by tethers into arrays is an operational configuration to validate. The proposal is that this method might greatly enhance safety & reliability.
Some Categories & Classes of aircraft & operations are interrelated. For example, UAS Aircraft & Flight Operations are clearly intimately coupled. On the other hand, a UAS might be operated as a Commercial or Private Aircraft.
Tethered Aircraft (TAC) that operate aerobatically & incur high G-loadings are Acrobatic Category (limited to 12,500lbs gross). Tether-Weight counts toward rated gross weight. Tether-Drag counts against rated L/D. Autonomous Flight of high-consequence platforms (high mass &/or velocity, especially around populations) require a proportionately more cautious rigorous path to validation & certification.
AWECS are generally high-duty UAS & so merit Utility designation. According to gross weight they can be sorted into Ultralight, Sport, Normal, Commuter, & Transport Weight & Airspeed Categories.
Operational altitude is a major category criteria. Some relevant ceilings- 400ft for low mass low speed hobbyist model aviation. 500ft as a "floor" for general VFR aviation. Class G airspace, which is  low, but variable, with higher ceilings in remote areas, 2000ft obstruction regulations for mast & tower certification, 18,000ft as an "absolute" ceiling to avoid transport aviation operations.
Note: Many current tethered vehicle platforms are not formally designated as an "aircraft" in the Aircraft Categories under current FARs, but the FAA reserves the right to designate them so. Its now clear that the tethered aircraft must be designated as aircraft so as to be regulated for airworthiness. The irrefutable logic is that any accepted aircraft can in principle be put on a tether, which does not negate its character as an aircraft of a given mass & speed envelope, & even adds to operational hazard. The many large tethered aircraft under development will have to be Type Certified in a suitable Category, a Special Class.
Pilot Categories & Training
Proper pilot training & testing is fundamental to every branch of aviation. All pilots in TA-shared airspace require awareness of the new conditions. All TA pilots require basic aeronautical training, plus specialized operational proficiency. As high-consequence risk emerges, TA Pilots will require the same high standards of certification as Transport Pilots.

Sec. 61.31 — Type rating requirements, additional training, and authorization requirements.

Operational Categories
Given Aircraft Types operate in diverse roles & regulations reflect this. Some major Operational Categories that are explicit or de-facto- , Remoteness, Altitude, Marine Environment, Unmanned Aviation System, IFR/VFR, Weight & Speed Cats., Obstruction, & so on.
Super Density Operations (SDO)
It has been proposed by some developers that AWE can operate under Obstruction Regs such as govern Antenna Farms, but such a model is only partial. For example, an antenna-farm Obstruction is also regulated under mast & tower structural codes not under the purview of the FAA. Towers do not have many inherent aviation hazards related to aircraft airworthiness & a potential to crash far afield. Therefore a TAC partly regulated as an obstruction still needs to comply with Airworthyness regs.
Current Norms & Regulations
 
The FAA's mandate to maintain a safe NAS already covers TA activity.   Certificating airworthiness within current regs is essential to prevent TA R&D from presenting a "menace-to-aviation". Most AWE venture starts have no formal aviation background & face acculturation along an FAA approved path. Class G Airspace is the primary realm of current TA R & D.FSDOs are the current arbiters of allowable experiments, with decentralized flexibility. AWE R & D can shop around for a "best-fit" FSDO (generally remote low-traffic NAS regions). Special Airworthiness Certificate in the Experimental Category is the certification currently available to civil operators of UAS. NOTAM & COAs allow pioneering AWE R & D to occur.
 
Obstruction regs, such as apply to antenna farms, can partly serve for persistent "static" TA operations under 2000ft AGL.Shielded operations is an option for a TA operator able to identify sites.
 
Draft FAA s UAS regs call for Pilot-in-Command & Visual Observer crews. A misconception in the AWE field is that autonomous operations will permissible in a short time-frame of a year or two, but the safer bet is that many years must pass before the required safety & reliability is validated & permitted.
 
Key Title 14 Parts of the Code of US Federal Regulations (Aeronautics & Space)

PART 101 - MOORED BALLOONS, KITES, UNMANNED ROCKETS AND UNMANNED FREE BALLOONS

Part 77 - OBJECTS AFFECTING NAVIGABLE AIRSPACE

The FAA regulates skydiving activity as"Parachute Operations" Part 105 (14 CFR 105). Flight operations for skydiving are conducted under Part 91 "General Operating and Flight Rules" (14 CFR 91).
FAA Advisory Circulars provide additional guidance about operations. A TAConOps circular is a logical step.
Banner-Towing & Glider Aero-Towing regulations inform equivalent operations in other applications.
Recreational  NAS use covered by FAA Advisory Circular (AC) 91-57; generally limits operations to below 400 feet ASL well separated from airports & air traffic. This is the appropriate place for virtually all current AWE developers to conduct most experiments without being a "menace to aviation".
Three acceptable means of operating UASs in the NAS: 1) within “restricted” airspace: or under a Special Airworthiness Certificate (2) Experimental Category or (3) Certificate of Waiver or Authorization (COA). A COA authorizes an operator to use defined airspace under specific provisions unique to the operation.  It may require Visual Flight Rules (VFR) & operation only &/or during daylight. COAs are issued for a specified time period; one year typical. COAs require coordination with air traffic control & may require a transponder in certain types of airspace.
A UASs inability to autonomously follow ”sense and avoid” rules means a ground observer (PIC &/or VO) must maintain visual contact operating in unrestricted airspace. The VO must also maintain aural vigilence in a quiet enough setting to detect airplane intrusion before visual spotting.
"Sense & avoid" UASs requirement currently means PIC (Pilot-In-Command) & VO (Visual Observer), plus dive or kite-kill capability.
Possibility of special IFR Rules clearances, especially higher operational ceiling during graveyard shift to help bridge night-time inversion.
TA Operations Notes
Tethered Aviation creates unique operational realities with particular hazards to mitigate.
 
A tether is a dangerous poorly visible obstacle when extended almost invisibly across large distances. Navigation markers are an existing requirement & will surely  long continue to be a good idea.
 
Separation, Avoidance, Visibility, & Education (SAVE) is a useful mnemonic for the basic principles of safe TA operations. S is for passive Separation; the relegation of TA operations to remote low-traffic airspace; A is for Avoidance; the effective evasive capability of a TA platform (ie. "kite-killers"). V for Visibility is the standard for obstruction markings, transponders, radar-reflectance, etc.. E for Education is the requirement to appropriately inform & train all pilots operating in proximity to TA, as well as the special Type-Rating knowledge a TA PIC needs.
 
 
Turbines on resonant composite wings can be quite noisy making the Visual Observer "deaf" to intruding air traffic (Often an airplane is heard before its seen, helping "sense & avoid".).
 
Special Risks- Mid-Air Collisions, Breakaway, Tether Dragging, Conductive-Tethers, Security,
 
APPENDIX
 
TACO/Nextgen Transformation Path
 
The general iterative-spiral validation process toward NextGen Integration-
Forward-Looking TACO:
The TACO Draft focuses mostly on near-to-mid-term AWE R & D. The forward-looking capabilities referenced below derive from the NGATS Vision Briefing of 2005 toward the NextGen Airspace CONOPS for 2025. Mature Tethered Aviation Operations (TAO) shall conform to these standards-
 
Notes:
Supervisory Override of Semi-Automated Flight is a bridge technology
NextGen's Moving Constrained Airspace is a capability needed for Tethered Free-Flight development 
EVFR rules for relaxed visibility will widen the TA flight envelope & be a bridge to Autonomous IFR .
 
 
 
 

Group: AirborneWindEnergy Message: 3259 From: dave santos Date: 3/26/2011
Subject: Fw: Toy Looper AWECS
This passive-control AWECS took ten minutes to make & runs like a clock in clean wind. Its a 99 cent eddy kite as a pilot, with a looping foil cut from a foam meat-tray.  Note how the power stroke pegs the spring scale-


Group: AirborneWindEnergy Message: 3260 From: christopher carlin Date: 3/27/2011
Subject: Re: An article upon HAWP
Dear Dave,

As a retired Boeing engineer who spent a lot of time at DRYDEN FRC I would have thought this would be the best candidate location.

1. It's already a flight test center with all the organizational mechanisms in place to do this sort of thing.

2. There are good winds over the area.

3. If you can get DFRC's attention, and I think someone there would be very receptive, they're very good at putting together concept demos on a shoestring. 

I don't know if she's still working or not but you might try contacting Jennifer Baer-Riedhart as a starting point. Otherwise you probably know someone there and certainly have the NASA phone book.

Regards,

Chris Carlin
On Mar 26, 2011, at 2:32 PM, davednorth wrote:


Group: AirborneWindEnergy Message: 3261 From: Pierre Benhaiem Date: 3/28/2011
Subject: Re: An article upon HAWP

DaveN,

Most AWECS can be experimented within F'AA's limits  (<150 ft w/o NOTAM, <500 ft. w/ NOTAM;comparable limits in France and other european states):reel-out,flygen,and others.

My idea is,in a first step, founding specific commercial applications within low altitudes before changing rules.Indeed we can separate the two goals of AWECS:1) harnessing HAWE but also 2) huge ratio Power/Mass (and cost) of invested material.

Such commercial applications could show an equal production than existant aeolian towers within  <500 ft. w/ NOTAM.If AWECS make a good work we can put into the balance advantages (little material, easy making,easy taking to pieces,low cost) and inconveniences (higher ratio space volume occupation/power,management, reliability).After a threshold of altitude where AWE becomes advantageous can be definited (certainly simulations can do it). 

Such a "legal" (necessary commercial because some technical problems have been solved) existence of AWECS could let a furthering projection towards really HAWE (add other AWECS like KiteGen carousel or Sky Wind Power).

In the case of changements of global energy policies and assessments,in the case where AWE becomes a major contributor,we can imagine a progressive transfer from space for travel planes towards space for AWE.

PierreB

http://flygenkite.com     


 

Group: AirborneWindEnergy Message: 3262 From: Joe Faust Date: 3/28/2011
Subject: OPTEC items

OPTEC - K.U.Leuven Center of Excellence: Optimization in Engineering 

Dear OPTEC Members and Friends,

this week we have two OPTEC visitors, a postdoc from the wind power industry (Sebastien Gros),
and a numerical mathematician and experimental design expert from Heidelberg (Le Zhang),
talking on Tuesday at 17:00 and Wednesday at 10:30, respectively, see the abstracts below.

OPTEC Members: please also reserve in your long term agenda
the dates of October 3-4 for "work in progress" meetings of all OPTEC WGs,
and the SAB on October 24, 2011.

Best regards,
Moritz Diehl


*********

Tue 29 Mar 2011 17:00-18:00, ESAT 00.62

"MMW wind turbine control & modelling of airborne applications"

Dr. Sebastien Gros,
MLS-Control, Glasgow, UK

Abstract

As they grow in size and power, the dynamics of multi-megawatts (MMW) wind turbines become more intricate and complex, resulting in new control
challenges. In the first part of this presentation, the dynamics specific to MMW wind turbines together with the classical control solutions will be
briefly presented. The more specific problem of emergency shut-down procedures and an optimization-based solution to fatigue reduction will be
detailed. In the second part of this presentation, two specific airborne applications (a rotary-wing UAV and a large-aspect ratio aircraft) and the
adopted modelling approaches will be briefly presented.


*********

Wed 30 Mar 2011 10:30-11:30, ESAT

"Parameter estimation and optimum experimental design with an adaptive method of lines"

 Le Zhang, University of Heidelberg

This talk is about the utilization of an adaptive method of lines, so-called moving finite element method (MFEM), in the context of optimization with
time-dependent partial differential equation systems as constaints, which may exhibit a high degree of spatial transition. The talk will be divided
into two main parts. In the first one I will introduce the basic idea and mathematical theory of MFEM. Subsequently in the second part some selected
numerical tests will be presented in the fields of simulation, parameter estimation and optimum experimental design, respectively.

**********

Group: AirborneWindEnergy Message: 3263 From: Bob Stuart Date: 3/28/2011
Subject: Re: An article upon HAWP
I hope that the government will treat AWE as a potential major benefit to national security, and accommodate experiments in most locations away from regulated airports and busy routes.  I think it would be reasonable to require transponders on kites and kite lines, and NOTAMs but otherwise, they should be able to fly at will.

Bob Stuart

On 26-Mar-11, at 8:32 AM, davednorth wrote:


Group: AirborneWindEnergy Message: 3264 From: dave santos Date: 3/28/2011
Subject: Shunting KitePlane AWECS Demo
Most sailboats tack (& gybe), but a special class, the Polynesian Proa, "shunts" (trades fore & aft ends) to accommodate its high performance bilateral asymmetry. Similarly a WingMill can be designed to tack or shunt. For three years now KiteLab's experimental wingmills have only self-tacked, with shunting kite flight explored by manual flying. A self shunting kiteplane was on the waiting list to demo, but emerged by accident last week when a model it did not tack as expected. A wingmill law-of-motion emerges that a longitudinally stiff kiteplane bridled near its CG naturally tends to shunt, while a longitudinally flexible kiteplane bridled ahead of its CP naturally tends to tack. Shunting is a powerful mode for an AWECS wing; a real-world example of a (rotary) shunting foil is the Aerobie flying ring where the strange foil section operates bidirectionally. This is a hot enough wing that the ring holds the record for hand thrown distance (+1000ft).
 
The little shunting kiteplane in video linked below was made in a few minutes from ordinary cardboard & a stick, & has the peculiar quality of being a conventional aircraft in one direction & a canard configuration in the other. There are a couple of secrets to its operation; the kiteplane hangs (from terrain or a lifter) as a classic mass-spring element & the fixed foils operate in-trim by the apparent wind created as the kiteplane rebounds from shunting. The wind power that excites it is extracted by damping tug.
 
Many Thanks to JoeF for hosting & posting these files!
 
 

Group: AirborneWindEnergy Message: 3265 From: davednorth Date: 3/28/2011
Subject: Re: An article upon HAWP (and more on Airspace Regulations)
I am hopeful that in the long term (15-30 years?) that AWE will have a place in the U.S. airspace regulations, especially with the better technologies that are coming and will be used in the NextGen airspace system.

However, in the short term, things look pretty challenging. If unmanned air systems are any indicator of the difficulty of changing FAA regulations, I think it will be an uphill battle. Potential commercial UAS companies have been trying for over a decade now to get new regulations written and the FAA is still struggling with it. I think most of the problem comes from addressing the "sense and avoid" requirement which is hard even when there is a human in the loop but not on board the aircraft. Maybe the UAS guys are doing the hard work for us in getting new regulations for automated systems, but I think tethered aviation has aspects (e.g. a tether) that make it different enough from UASs that it will require new regulations that are different from the UAS regs.

I still think that a lot of development work can be done under Part 101 (<500 ft.) and maybe some can get waivers to part 101 if the location is remote enough (I think Makani has been successful in doing this in Hawaii).

I'm not a rules and regulations guy (I'm a design engineer), but we hope to bring more people who are airspace experts into the growing number of researchers interested in AWE at NASA who can help in regulations negotiations with the FAA.

Dave North

Group: AirborneWindEnergy Message: 3266 From: Joe Faust Date: 3/28/2011
Subject: Re: Shunting KitePlane AWECS Demo


Do these phrases work for the species?

 Shunting kiteplanes
 
Kite-lifted inline-tethered cross-winding shunting kiteplanes
 Terrain-held inline-tethered cross-winding shunting kiteplanes

Group: AirborneWindEnergy Message: 3267 From: dave santos Date: 3/30/2011
Subject: Please Forward to Ben Harder ("Start-ups are devising kites..." Mar2
Hi Ben,
 
Please provide any logical basis & sources (or the rationale to conceal them), for the following claim made in your article-
 
 
"Some independent experts say Makani, which has attracted investments from the Department of Energy (through a $3 million grant) and Google, is leading the pack technologically."
 
 
I would like to question this, if The Post will please listen to a counter-view,
 
Thanks,
 
dave santos
KiteLab
 
======================================
 
From the Washington Post-

Start-ups are devising kites to turn wind power into a cheap ...

By Ben Harder, Monday, March 21, 4:02 PM. Kites of all shapes and sizes will take to the breeze Sunday, filling the airspace around the Washington Monument.
 
 
Group: AirborneWindEnergy Message: 3268 From: dave santos Date: 3/30/2011
Subject: Popoular Mechanics features AWE Consortium (online link)
Group: AirborneWindEnergy Message: 3269 From: Joe Faust Date: 3/30/2011
Subject: AWEA conference wants diversity without AWE, apparently ...

AWEA coming conference  in Anaheim (conventional wind) wants journalists to have media passes,
and they want "diversity" in that media-pass pool.  They are denying a media pass to
the editor of UpperWindpower in two cycles of requests; a third request for reconsideration is underway.
They have been been given clues that AWE will be purchasing parts from many of their attendees.  AWE
seems to be yet not recognized as a sure diversity flow in windpower.     No hurry. But one day there may be
more sellable energy from AWE than from towered conventionals.

I will report final result.

Group: AirborneWindEnergy Message: 3270 From: Joe Faust Date: 3/30/2011
Subject: Tether cousins: Space elevator
Welcome to ISEC
  http://www.isec.org/

Base StationWelcome to the new and improved ISEC website. We hope that with this new look we will be able to continue the success of 2010 and make a place on the web that is THE authority on the Space Elevator.

============================================================
An effort parallel with AWE movement is the Space Elevator movement.
Airspace? Tethers? Communications? Tethr travelers? Aloft stations? Advanced materials?
Safety? Education of new airspace uses? Energy transfer?  Etc.

Group: AirborneWindEnergy Message: 3271 From: Doug Date: 3/31/2011
Subject: Re: AWEA conference wants diversity without AWE, apparently ...
I attend most AWEA Windpower events.
I can tell you it is an "industry event", meaning the industry as currently configured. You may find a few engineers interested in AWE, but overall the entrenched players have their own busy day using their own design. They've seen and heard it all. Anyone in AWEA can rent a booth. So join, pay for a booth and become part of the comedy act. Every year there is a comedy area where Korean companies display their colorful cross-axis maglev vertical-axis machines etc.

Everyone laughs - the wacko machines, usually powered by fans in an attempt to look impressive, makes a great ice-breaker than everyone can agree is funny. The real wind turbines don't need a fan to prove they can rotate in response to wind, but the wackos seem to believe that their mere forced rotation in still air is as much proof as veterans used to watching their machines crank out a megawatt or more need to see, to realize that their megawatts pale in comparison to the likely 1-2 watts of the demo oddball machines on the showroom floor.

I used to obediently prepare papers and talks on my multi-rotor technology, expecting to be invited to speak, since I was asked to apply. Each year I'd think "Well they probably had a full roster - maybe next year". Slowly it dawned on me that promoting my designs were another way of saying everything the industry was doing was wrong, and why do they want to hear that?

My wake-up moment came when talking, in passing through their booth, with a company that had an improved gearbox. I mentioned that my multi-rotor technology allowed more area to be swept at high RPM, making gearboxes unnecessary.
"Get out of here then" was the good-natured response. But I did realize that to try and tell all the industry players how your technology is going to make all theirs obsolete is not welcome.

Same with NREL etc. All Airborne WInd Energy is to NREL is evidence that they are not at the front of the curve, but are instead responsive to the status quo, with all "research" programs unconsciously staying so "safe" that they serve to petrify technology at its current state rather than advance it. I mean, if NREL is meaningful, and AWE were promising, the wouldn't NREL already be doing it? We know the answer, but to them, it's better to avoid that answer. So you will find that they are real "busy". In fact the NREL booth will be the least impressive of all, if you can find it, usually unmanned, or sometimes a blonde lady with glasses will be there, to tell you everyone is "in a meeting". They may have a poster up or a Southwest Windpower Air-Breeze on a table (4-foot diameter) You'll think you are at a childrens' daycare booth rather than the NREL booth.

Believe it or not, most of these people are BUSY building turbines and making power. Overall these trade shows are just one more way to waste your time - one more excuse - one more way to pretend that your time and money are pursuing a goal when in reality you are joining with the others who are avoiding that goal, spending (wasting?)a few more days without building or proving anything.

Said it before and I'll say it again: One working system of any kind that is useful for any purpose is all it will take for this art to "take off" and without that one useful product, you might as well spend the rest of your life attending endless trade shows, crafting endless websites with renderings, issuing meaningless press releases, and blogging yourself to death.

Just remember nobody takes anything seriously unless it takes itself seriously, so get a useful product running and get at least to the first rung on the ladder of success and the ladder of credibility.

This year the AWEA Windpower 2011 is in my area and I'm so jaded and bored at these repetitive events where the same companies have the same booths, that I may not even show up for one day this year.

I only say all this since I doubt if most people on this list have ever attended a wind energy event. Just "another trade show". Are you in the trade? Didn't think so. Well don't get too excited. Most of the booths are for people selling wire, bolt torquing machines, steel tower rolling machines, big trucking forms to move the turbines, riggers, insurance companies, etc.

While the show can be exciting in some ways, it will not be what you think. You won't go to the Vestas or GE booth and have them clambering to drop all their plans to adopt your oscillating kite contraption or whatever you may have. You will have people walking by you ignoring you as you stare at the giant displays and wonder how soon before they serve more food. By the end of the day you will wonder if it was worth all that money and time since all you've gotten out of it is the fact that your feet hurt and you wonder where the heck you parked anyway...

By the way we had a very low wind day yesterday, so I was able to fly a kite for a few hours. (most windy days here my 9-foot kite would be ripped out of my hands and quickly shredded) I used a 500-foot line from Home Depot and let it all out. My thoughts were:
1) If any plane flew this low they'd be lucky if people around here didn't take a few pot shots at them.
2) I hope I don't get in trouble for flying a kite on a 500-foot line!
3) This line is making a singing noise if I put my ear to it or touch it to a hollow object - maybe Dave Santos can turn those phonons into power! (hi Dave!) Go to the show and run it by GE! :)
:)
Doug Selsam
http://www.selsam.com

Group: AirborneWindEnergy Message: 3272 From: harry valentine Date: 3/31/2011
Subject: Re: AWEA conference wants diversity without AWE, apparently ...
Practically all high-powered wind energy is subsidized by government (off-grid being the main exception). AWEA people are cozy with government officials .  .  .  .  .  . some of the activity borders on lobbying government.
 
AWE has operated well outside of government .  .  .  . which is to its merit. Economic conditions are tough in many countries .  .  .  .  . some 90,000-workers may be laid off in the UK should their gov't cut back expenditures on subsidized solar power and subsidized wind power.
 
It is essential that AWE technology be developed to operate free from government subsidy .  .  . in any nation. AWEA may already see the writing on the wall .  .  .  . the day will come when the subsidies end. Such a development would make AWE quite competitive.
 
 
It is to the benefit of AWE that AWE and AWEA follow distinctly different paths.
 
 
Harry

 

To: AirborneWindEnergy@yahoogroups.com
From: joefaust333@gmail.com
Date: Wed, 30 Mar 2011 18:18:27 +0000
Subject: [AWECS] AWEA conference wants diversity without AWE, apparently ...

 

AWEA coming conference  in Anaheim (conventional wind) wants journalists to have media passes,
and they want "diversity" in that media-pass pool.  They are denying a media pass to
the editor of UpperWindpower in two cycles of requests; a third request for reconsideration is underway.
They have been been given clues that AWE will be purchasing parts from many of their attendees.  AWE
seems to be yet not recognized as a sure diversity flow in windpower.     No hurry. But one day there may be
more sellable energy from AWE than from towered conventionals.
I will report final result.

Group: AirborneWindEnergy Message: 3273 From: dave santos Date: 3/31/2011
Subject: Phonon Power? (Reply to Doug)
Doug wrote-
 
This line is making a singing noise if I put my ear to it or touch it to a hollow object - maybe Dave Santos can turn those phonons into power! (hi Dave!) Go to the show and run it by GE! :)
 
 
We clearly see that GE is not living up to its hype, the whole Ecomagination farce is a PR cover for its nuke & gas-turbine profit centers.
 
Re: Phonons///  You can get a milliwatt or two from a singing kiteline by using a piezo-bimorph, but lets agree such an unoptimized AWECS is not impressive. It takes a real engineering imagination (like Wayne's) to see that we can fill the sky with cheap wings & ultimately create terrawatts of power. Interestingly, all AWE schemes with mechanical cycling are highly "phononic", but the frequencies are super-low infrasonic, so most folks will not recognize them as an acoustic phenomenon.
 
The newest frontier in AWE thinking is vast kite-based lattices that exhibit powerful bulk harmonics to tap, sort of like turning a portion of sky into wiggling Jello. A gigwatt scale AWE plant on this principle would fit into a volume roughly 1km x 1km x 1/2km high & sing a monstruous song.
 
daveS
 
 
Group: AirborneWindEnergy Message: 3274 From: Theo Schmidt Date: 3/31/2011
Subject: Re: AWEA conference wants diversity without AWE, apparently ...
Doug schrieb:
Good write-up, Doug, but why on earth to you go to these things?

Cheers, Theo
Group: AirborneWindEnergy Message: 3275 From: Doug Date: 3/31/2011
Subject: Re: Tether cousins: Space elevator
I was contacted years ago by Michael Laine, with obvious similarities between the space elevator concept and airborne versions of Superturbine(R). Both ideas (can) share the need for a long, lightweight working element, probably best made of carbon fiber or nanotubes, that would reach far into the sky.

I was initially very honored to have been contacted by Michael Laine, and sought to emulate his progress. "Wow, if only I could become THAT SUCCESSFUL!" I thought. "Those guys are real players that are taken seriously - I've seen so many articles!". Then slowly, it began to dawn on me that they were probably never going to produce anything besides a lot of hot air - they were addicted to conferences and the all-talk format, and broke, and producing any useful product seemed like only a peripheral interest to them. I began to realize that they were an example of what I needed to AVOID becoming, not to emulate them, as much as I like the people involved and their enthusiasm for discussing new ideas. Discussing is one thing, developing is another. Success is more elusive still.

My take on "space elevator" has been that it looks like a neat idea, though safety & regulatory issues seem problematic, while progress is slow to nonexistent, meaning that those issues will not be faced for a long time, since, unless you can make a "full-size" space elevator, it won't work, and that is such a huge scale that it won't happen anytime soon.

Issues like the surprise static-electric event on one space tether that was tried will probably be even bigger problems (or bigger solutions) with a full-size space elevator that goes from space to Earth, than with a tether a mere few miles long. And of course the promoters will have to insure that the thing can't come crashing down on everyone - how do you do that?

I guess a lunar space elevator would seem to be a better place to start. Far smaller or lighter duty needed, and no atmosphere to deal with, though it's further away. So far we have not built much on the moon, ya know?

No matter how you look at it, the space elevator is in a similar position to AWE - a neat and tantalizing idea with no useful product available now. In the case of space elevator I have racked my brain to try and come up with useful products that Michael Laine and Liftport could produce NOW, and certainly there are many possibilities. I don't see them doing it. They seem to be stuck in first gear or maybe neutral. This is one more example of how focus on a single useful product will do more than all the talk in the world.

Take heart: While space elevator is almost 100% pie-in-sky at this point, AWE is achievable without leaving the planet or even going very high at all, and can be done any day anyone wants to actually DO IT on a shoestring budget. So while we are LIKE space elevator in SOME ways, we have the option to be "for real, here and now" while space elevator will probably be a mere dream for many many years.

Space Elevator should only be so LUCKY that it should be a simple and easy to achieve as AWE. They have lots of excuses. We have NONE!
:)
Doug Selsam
http://www.selsam.com

Group: AirborneWindEnergy Message: 3276 From: dave santos Date: 3/31/2011
Subject: The Kite as Philosopher's Stone
 As a five-year-old, Pocock tied a toy kite to a rock & "wondered" to see it drawn along the ground. Wow, the kid conjured a real Philosopher's Stone, a substance capable of turning symbolic lead to gold & conferring immortality. All AWE is the extension of this illumination event.
 
Its recorded that Newton, at age 13, was obsessed with kites; deeply pondering the physics while also pulling-off notorious UFO pranks. Kiting prepared his mind for the famous Laws of Motion; no coincidence that NASA school materials feature kite physics to explain Newton.
 
Franklin found in the kite a first-class basis for multi-disciplinary science. In his most iconic guise he holds a kite. Illustration entitled "THE PHILOSOPHER AND HIS KITE," depicting Benjamin Franklin-
 
  
Wittgenstein's Tractatus Logico-Philosophicus is reckoned as the most important philosophical text of the 20th Century. Once again the kite acted as muse, for Wittgenstein began his carreer devoted to technical kiting & aeronautical engineering. His philosophy was based on the functional organization of flying machines.
 
 
Churchill famously said, "A kite flies highest against the wind". Shakespeare was reported to be a avid "kyter"- "My soul is in the sky." 'A Midsummer Night's Dream,' Act V. Scene I
 
Blind & deaf, nevertheless, little Helen Keller apprenticed in kites over a period of years with Dr. Bell. Who can doubt the kite did its part to lift her mind altogether beyond.
 
picture-101
 
It's wonderful to climb the liquid mountains of the sky, Behind me and before me is God and I have no fears.
— Helen Keller, at 74, on flight around the world. in 1955
 
 
 
 
 
Group: AirborneWindEnergy Message: 3277 From: Doug Date: 4/1/2011
Subject: Re: AWEA conference wants diversity without AWE, apparently ...
Hi Theo and thanks for asking why I bother to attend AWEA events.

Well the thing about seeing the same people over and over every year - I guess I'm one of 'em.
In spite of my pointing out how NREL doesn't research new turbines, I DO have friends that work there, and actually they share my opinion - they also wish their organization tried new things. They are just stuck there with "a job".
My Superturbine(R) technology IS taken seriously in many circles.
I manufacture small turbines and know all the small turbine people and many of the big turbine people. I usually have people saying hello that I don't even recognize, since I have "a name" in "the industry". It's always good to meet more wind people and see the latest turbine models, and discuss with their designers and promoters all the salient aspects of overspeed control, stall regulation, types of generators, ways of putting power to the grid including but not limited to inverters, all the stuff that breaks and all the stuff that works.

There will be Harvard / Stanford grads there who made me a 20-million dollar offer before the big economic crash. The only reason Superturbine(R) has not gotten further along by now may be me and my own snoozing/stupidity. I have to admit that. I also turned down a licensing offer from Canada. I can be really dumb. Like most inventors, I can stand in the way of my own progress. But at least I can see it and then maybe do something about it.

I DO remember being at one show and the market leader of small turbines (Bergey) was not there. (I have a 10 kW Bergey on a 120-foot tower powering our new facility now).
"How could Bergey not be here?" I asked in astonishment.
Well another wake-up moment:
I realized Bergey is in the business of making, selling, and servicing turbines, not "attending trade shows".
I realized that it is quite possible that even a major player in an industry may actually have better things to do than spend thousands of dollars and a week's time to stand around yakety-yaking it up and posturing. That someone "in the business" might just have "business" to handle, and be too "busy" to attend a trade show.

So that's what I mean: I usually feel obligated to go, but if you miss it, you didn't miss that much. And in the case of people thinking about large oscillating walls of kites making power, what use is a show about large propellers? I'd recommend spending the same amount of time and money building a supported version and see if you can get it working at all, or get it to survive high winds.

But one thing is for sure, typing is way easier than building anything and proving all the words that one types.

In the end, neither the typing nor the trade shows matter. They are all "waves" in the sense of being hard to pin down... Only the sale of a product is "a particle".
:)
Doug S.

Group: AirborneWindEnergy Message: 3278 From: dave santos Date: 4/1/2011
Subject: Power Plant Direct Staffing Requirements
Leading proponents of robot kiteplane AWE, like Joby Energy & Makani Power, insist that avoiding labor costs is the decisive advantage of full autonomy; that they can field "launch & forget" aerospace systems able to operate with ultra-high availability, even for a year at a time, with minimal human intervention. On the other hand, proponents of low complexity AWE, like KiteLab Group, find such claims over-optimistic, that such high perfection of flight automation & its regulatory acceptance is decades away, & that considerable human staffing of AWE is required, much like the supervised automation that aviation & aerospace currently relies on.
 
Various kinds of conventional power plants have very different direct staffing requirements. A general trend is for ever larger plants with more power capacity per staff person. Surprisingly, nuclear energy is fairly staff intensive, with roughly 500 staffers to operate & maintain a gigawatt scale plant. This number will temporarily increase given recent safety & security lessons. Coal plants are also staff intensive, with a considerable variety & quantity of handling equipment, for an estimated 200 direct workers per gigawatt. Gas Turbines are relatively simple & compact & employ an estimated 50-75 workers. Hyrdoelectric plants seem to be the least labor intensive, with even lower staffing requirements per unit of energy.
 
Early low-complexity AWE is estimated by KiteLab Group to require direct staffing comparable to a nuke, based on a modern commercial fishing model of about 2 megawatts of equipment handling per crew member, or roughly 500 direct staff per gigawatt of low-complexity AWE production. It is proposed that these jobs are a social good & can be sustained for a considerable time economically competitive with struggling autonomy. 
 
This is not the entire "jobs picture"; there is the work to fabricate & build a plant. Hydro & nuke projects generally employ a vast workforce up-front for a period of a few years. Coal & gas plants have a lesser, but considerable, manufacturing labor component. There is also a steep pay-scale between lower skilled jobs like coal handling & more technical jobs, especially in nuclear energy. Aerospace manufacturing is fabulously capital intensive, with lots of skilled factory work, but the manufacture of low-complexity AWE might (ironically) be based on high speed automated production lines fed from COTS roll-stock. It may be that autonomous & supervised AWE co-exist with comparable job creation, the biggest difference being between better paid shut-in factory work & lower paid adventurous outdoor work.
 
The labor question is still open; much more analysis is required. The full-autonomy camp should try to better support its case. In any event, time will tell. 
 
 
 
Group: AirborneWindEnergy Message: 3279 From: dave santos Date: 4/3/2011
Subject: Isotropic Kite Demo (Scale "Large-Array" Model)
A typical kite flying on its tether is anisotropic; it must maintain structural direction into the wind dependent on the tether rotating around its compass & the kite weathervaning. Similarly, a large kite arch must rotate as a whole to follow wind direction. This sets a limit to how big an arch or 3D array can be & still rotate in real-time. A related space utilization limitation is for the anchor point to be fixed at the center of the "rose" (or in the arch case, abeam of the center), rather than the anchoring shifting fully windward, allowing higher flight while still always staying within tight bounds when forced to land. On cannot merely stake out a kite or array radially without excessive slack of the downwind lines & suboptimal AoA. Another problem is reliance on a single tether: When it parts the result is a breakaway event, AWE's general worst-case scenario.
 
The latest tabletop demo shows a solution to all these problems. A Tri-Tether pulley or winch anchor triangle allows an isotropic kite or kite array to adapt & receive wind from any direction; to passively tune its AoA & fly from windward anchors, without rotating. While the demo uses a common paper plate as a "Sedgwick UFO" style kite element, the intent is to suggest a vast kite array, possibly a fractal Play-Sail or "Ohashi-Mesh". During the test session in fluky wind the plate self-launched many times, adapted without fuss to rotating the tabletop, & flew with decent stability. Envision this concept at an early full scale of 2000 ft regulatory altitude within a rose approximately 1 km across, or as an ultimate version 10,000 m high by about 20,000 m across, even spanning a major city.
 
A modest Isotropic Array could land its center (or legs) on a tower(s) or hill(s) and a giant version center on a  mountain to keep array elements clear of the ground. The versatile tri-tether is also suited to tow a kite or array in circles, for persistence in calm. One can also imagine this adaptive mechanism as a cellular unit in a larger fixed lattice, compliant to array-scale turbulence. A hybrid design option is anisotropic kites on an isotropic lattice using classic kite train connections like thru-bridling and tri-swivels.
 
coolIP
 
Thanks once again to JoeF for encouragement, hosting, & posting-
 
Group: AirborneWindEnergy Message: 3280 From: simon_0987 Date: 4/4/2011
Subject: In which countries can you fly your kites legally?
Hi,

I gather that in the US the FAA only allows you to fly your kite below 500 feet?

In Europe, I gather the EASA only allows you to fly your kite below 100 meters?

What do you know about the regulations in other countries?

I will assume you don't know the specifics for each country, so maybe you know which government agency is responsible for a country?

I don't much care where I go. (North & South America, Europa, Eurasia, South Asia, East Asia, Oceania, Africa)

Specific regions of interest might be the Qinghaiâ€"Tibetan Plateau, mountainous areas, desert areas and coastal areas.

But for now I don't care. I just want to test something high up in the air.



My interest is in mainly in tethered balloons, by the way. I am assuming the regulation is similar.

(I'm also intrigued by international waters. Would it be legal to do it there?)
Group: AirborneWindEnergy Message: 3281 From: Pierre Benhaiem Date: 4/4/2011
Subject: Re: In which countries can you fly your kites legally?

Hello Simon,

It is a good thing to know the laws in the world for an appropriate choice of the experimented system.In France kite is free under 50 meters,between 50 and 150 meters with an authorization,above 150 meters with a planning of flight.

PierreB

http://flygenkite.com

Group: AirborneWindEnergy Message: 3282 From: Pierre Benhaiem Date: 4/4/2011
Subject: Makani M1

On Makani website datas for the expected prototype M1 are;span = 35 m,and nominal power of 1 MW is reached with wind velocity = 9 m/s.Illustrations show a very thin design:the width of the wing should be about 3 m,maybe 5 m,but not more.So with an area of 175 m² the power could be formalized as following:

4/81 aD A w3 CL(CL/CD)² with aD = air density;A = kite area;w = wind speed;CL = lift coefficient;cD = drag coefficient;4/81 is the transformation of 2/27 (see Diehl's formula and the link below) after conversion from a reel-out system towards a flygen system,including Betz limit and drag of an ideal rotor (8/9);

So 4/81  1.2  175  93   1.2 = 9072; complete formula is:                                                      4/81  1.2  175  93   1.2 (1.2/CD)²

To obtain 1000 000 W with 70 % of losses (comprising Betz limit): 1000 000/6350.4 = about 157.47 ; square root of   157.47 is about 12.549

So (CL/CD) should be the value of 12.549 which is also the ratio kite speed/wind speed.

So kite speed should be (12.549) 9  2/3 =75.294 m/s.  2/3 is the optimal kite speed after slowing down because of turbines. 

So the tip speed of turbines aloft should be some value like 300 m/s .

Thank you for corrections and comments.

PierreB

http://flygenkite.com

http://www.energykitesystems.net/OrthoKiteBunch/OptimizationOfAManualFlygen.pdf

   

     

 

Group: AirborneWindEnergy Message: 3283 From: Pierre BENHAIEM Date: 4/4/2011
Subject: Re: Makani M1
Correction of the precedent message:"To obtain 1000 000 W with 70 % of losses".It is 30% of losses,and 70% of the initial value.

PierreB
http://flygenkite.com  




Group: AirborneWindEnergy Message: 3284 From: dave santos Date: 4/4/2011
Subject: Re: Makani M1
Pierre,
 
Its very hard to properly model these AWECSs with so many unknowns. A major factor needed in your calculation is the gross weight of the kiteplane & conductive tether. Just keeping this dead-load flying subtracts useful power. Another factor is the conductive loss of the tether, a complex trade-off with safety factors. There is also waste heat to dissipate at the generator, extra turbulence from the fat symmetrical turbine fan, trim-drag, & so on.
 
Nevertheless, your initial numbers are usefully suggestive of some key issues. Even at just 9m per sec wind speed, the turbine is already above Mach .8, so its not hard to see that the fan operates close to the edge of a practical performance envelope where it must either stall or go supersonic. Makani intends that the plane can reliably stop its sweep pattern & park at zenith to adapt to high wind, but overload can easily come very fast within a loop cycle,
 
daveS
 
 
 
Group: AirborneWindEnergy Message: 3285 From: dave santos Date: 4/4/2011
Subject: Joby Energy Mishap Report for the Incident Case-Base
The Popular Mechanics article inadvertently gave us a third Joby Energy Mishap Report to add to our AWECSs Incident Case Base. No surprise that a flygen* prototype electically overloaded-
 
"... the plane was rocked by a pop, it belches a ball of fire, zigzags & lands hard."
 
Its probable that a full-scale airframe would have been totalled. A technician was present with a fire extinguisher, but add wildfire to the list of known flygen risks.
 
 
Notes-
 
A continued painful pattern of prototype failures is predicted for the inherent high-risk AWE concepts, despite tens of millions in capitalization. Makani Power has been far more careful to hide failure from the public & does not share safety-critical failure-mode knowledge (by non-responsiveness), even though transparent aviation safety-culture saves lives. Despite "iron-clad" NDAs venture employees are forced sign, rumors & clues are leaking.
 
Given the limitations of aerospace, large Joby & Makani prototypes announced for 2013 face certain doom if allowed to operate autonomously for extended periods. Early regulatory approval is not likely either, so don't expect the products hyped can be brought to market. The companies can hope to fly just enough to interest continued investment. A crunch comes if they fail to inform prospective investors of critical mishaps, as a legal duty. Before disclosing, they will tend to also require NDAs of prospective investors, to protect a rosy public image.
 
 
* Not to be confused with Pierre's recent FlyGen TM.
 
Group: AirborneWindEnergy Message: 3286 From: dave santos Date: 4/4/2011
Subject: Re: Makani M1
Pierre,
 
you wrote- Correction of the precedent message:"To obtain 1000 000 W with 70 % of losses".It is 30% of losses,and 70% of the initial value.
 
This raises another intesting question; is a turbine on a wing subject to a double Betz Limitation penalty?
 
The looping kiteplane wing is the primary turbine & 60% max Betz efficiency is not practical (tether drag, etc.), so presuming 50% is less over-optimistic (& rounds the math). The turbine discs on the wing are also Betz limited & suboptimal (VTOL trade-off) & the two limits sum for a predicted  25% max efficiency, which seems reasonable.
 
Note that looping kiteplanes leak a lot of wind energy thru the center of the loop & have the added induced drag of the inside wingtip, compared to a hub mounted turbine blade, so a direct comparison is not easily realistic,
 
daveS
 
Group: AirborneWindEnergy Message: 3287 From: Pierre BENHAIEM Date: 4/4/2011
Subject: Re: Makani M1
DaveS,

I have not the exact area.70 % Betz limit is for a good rotor.If we  take into account other parameters like conductive tether,real aerodynamic losses,tether drag (see Lansdorp's studies) etc...,losses will be by far higher,and the needed ratio CL/CD (and tip speed of turbine) must be higher for the same area of the wing to obtain 1 MW with wind speed = 9 m/s.

Yes there is a double Betz limit.However Diehl's formula does not take into account the global surface of the swept area but only the potential of kite according to wind speed.And 2/27 of reel-out (during power phase) becomes 4/81 of flygen with an output of 100% Betz limit (16/27),coefficient of rotor drag being 8/9 (so the inverse 9/8 is within formula);that before calculation of other parameters.

PierreB

http://flygenkite.com  



Group: AirborneWindEnergy Message: 3288 From: Pierre BENHAIEM Date: 4/4/2011
Subject: Re: Makani M1
DaveS,

When Makani gives a nominal power of 10 KW for such a prototype (M4) Makani's curve is about 4 KW for the lower value,and 9 KW for the higher value,according to the cyclic (5 secondes) variation of power.So it could be the same for the 1 MW prototype.

My idea is beginning to see the difference between a mount on a stick under a kite of type parafoil (FlygenKite) and a mount on a rigid wing (Makani),excepted the specific use of FlygenKite as a cheap model making to load batteries.Other idea is the probable limit of altitude with a flygen according to actual technologies. 

PierreB
http://flygenkite.com