Limit Lines from TCF to Pilot

Limit Lines from TCF to Pilot

We expect that limit lines from the triangle control frame to the pilot have been discussed prior to the dates shown in the following notes by JoeF and Tony Prentice. Combinations that might include limit lines from triangle control frame (TCF) to pilot or pilot pod or harness, wide wheels, rollers, skids, skis, sitting, supine, planning, instruction, practice, conservative flying, rear limit lines, and other Safe-Splat tactics (which see and discuss) may advance safety for hang glider pilots.

Situations of concern:

Landing
Aborted take offs
Failure to hook in
Failed looping
Over the falls
Bouncy turbulence
Zero-g
Pilot faints or goes unconscious
Collisions

Earlier discussion notes? We welcome others to send references on topic for inclusion. Thank you.

1800-1958 ??

1959-1975 ??

1975-2010 ??

Year 2011

Limit lines. Staying lines.
May 2011 issue of LIFT: " = With the referred sketch of the TCF with ski and frontal flying canard wing skid, there might be a limit line to pilot torso that prevents vertical rising of the chest as the pilot moves forward some." ~ JpF
Dec. 28, 2011: ""On pilot-body arresting: Limit lines from the bottom of the queenposts (downtubes of triangle control frame TCF) would perhaps be an option to the BobK stepped arrestors or in combination with such."" JpF
Showing pilot-arrest in combination with vertical slap cushion and alos forward ski skids.
Dec. 28, 2011. JpF
Combination of limit lines from TCF to pilot with a roller-when-wanted RWW.
Dec. 29, 2011. JpF

Year 2012

January 1, 2012: "Arrest-limit lines without rebound to be based from the lower end of the two queenposts
(uprights; downtubes; sides of control frame; side edges of triangle control frame (TCF) )???" JpF
JoeF » Mon Jan 09, 2012 9:30 am

Invited all: to forward arrest lines for Safe-Splat systems.
We need to retain flying control authority in any solution.

Year 2013

JoeF » Tue Mar 05, 2013 10:29 pm
Exploring sending compression into tension result.

FaustProneSafeSplat2.jpg (15.94 KiB) Viewed 375 times

Safe-Splat concept not found elsewhere, but probably such has been explored:

Instead of having helmet increasing the mass that gets whipped about,
have impact forces sent to shoulders, hip, ankles in such a manner
that the legs and neck and head get tensed instead of compressed.
Change compression of impact into a scene that does not crush the neck or head.

December 7 and 8 and 9, 2013:

Having looked at the proposed restraint lines to the keel as shown here :- http://ozreport.com/forum/viewtopic.php?t=34886&start=50 I thought that it might be better to clip a line from the base bar to the harness with sufficient slack to allow full control but not as far as to hit the nose. The line could a have a rewind spring so there is no slack to get caught up on any thing. (dog leads have such recoil mechanisms.)
Just a thought; no real measurements or calculations done. ~ Tony ARP
It would also prevent a pilot in strong turbulence hitting the keel when weightless. If a loop were to be attempted and the pilot gets it wrong it would restrain the body mass and the glider should be able to recover? Tony ARP
PS: Just thought that it also gives a backup in the event the pilot does not clip in properly with the same control as on the original ski kites attachments. ~ Tony ARP
Dec. 8, 2013: Tony, The three email notes on the limit lines from the basebar have been received. We might gather notes carefully and put up in OZ and US Hawks something. ~JpF
Tony, your suggestion of rewind is important.
The loop-fail aspect is also important.
And the backup on hook-in-fail!

I don think we are first on this direction of consideration, but I do not have on table any references.
It seems easy to me that acro pilots may have discussed basebar-to-pilot limit lines for loop-fail
or over-the-falls tumbles and turbulence drops, etc.

Do you want to use your notes and mine in an OZ Report presentation? Feel free.

There were broken necks in early 1970s from slamming head into beaking keel.

Bare basebars or bare downtubes on TCF... or even tiny wheels that easily gouge so many soil textures
just seems like hang gliding has not learned its lessons. Even the best of pilots still whack. And the cost
can be fatal.

Best, ~ JpF
When flying seated there was less chance of hitting the keel and more chance of breaking a control frame upright along with the wrist or arm. Going prone allows the follow through, by the pilot, to contact the nose area. For pilots to adopt any restraint system it will need to be as simple as possible and the trapeze bar anchor idea might be acceptable. The recoil could be built in to the trapeze (base) bar or the chest area of the harness. An alternative could be a simple bungee cord inside a tube strop which would automatically centre a pilot to the neutral control position. If a pilot were to become unconscious due to illness or lack of oxygen then the glider might have a chance of landing without pilot input. The restraint line need only be long enough to allow full control input which would be about 60 cm.

There is the possibility that the forces in a follow through might break the base bar which would be in shear from the line. However considerable energy would have been absorbed before that were to happen reducing the kinetic energy of the pilot mass.

I have not seen this idea used or even suggested but as it is so simple it would not surprise me that it had. If you want to add it to the US Hawks and Oz Report threads then please do so.

The addition of skids/skis on the base bar do go a long way to negate the problem of the control frame digging in and a combination of the two ideas would make things far safer. ~Tony ARP 9 Dec 2013
It would also prevent a pilot in strong turbulence hitting the keel when weightless. If a loop were to be attempted and the pilot gets it wrong it would restrain the body mass and the glider should be able to recover? ~ Tony ARP
When flying seated there was less chance of hitting the keel and more chance of breaking a control frame upright along with the wrist or arm. Going prone allows the follow through, by the pilot, to contact the nose area. For pilots to adopt any restraint system it will need to be as simple as possible and the trapeze bar anchor idea might be acceptable. The recoil could be built in to the trapeze (base) bar or the chest area of the harness. An alternative could be a simple bungee cord inside a tube strop which would automatically centre a pilot to the neutral control position. If a pilot were to become unconscious due to illness or lack of oxygen then the glider might have a chance of landing without pilot input. The restraint line need only be long enough to allow full control input which would be about 60cm.

There is the possibility that the forces in a follow through might break the base bar which would be in shear from the line. However considerable energy would have been absorbed before that were to happen reducing the kinetic energy of the pilot mass.

I have not seen this idea used or even suggested but as it is so simple it would not surprise me that it had. If you want to add it to the US Hawks and Oz Report threads then please do so.

The addition of skids/skis on the base bar do go a long way to negate the problem of the control frame digging in and a combination of the two ideas would make things far safer.

~ Tony ARP
?