Fatal Towplane Accident 5-9-20

Has anyone investigated placing the tow hook directly over(or under) the tow planes center of gravity? This would keep the out of position glider from yanking the tow planes tail out of acceptable limits? The RC tow ships, I have seen, place the tow hook over the towing ships CG.
My 2 cents,
JJ

seen, place the tow hook over the towing ships CG.
My 2 cents,
JJ

Mic drop?

Clever concept. Would the release have to be precisely at the CG/CM? If for example it were above the CG/CM point, then would the tow pilot have to apply constant down elevator to overcome the asymmetric leverage caused by the glider's drag? Would the glider pilot be much busier trying to fly in line with the longitudinal axis of the tug?

The moment arm up (or down), from the tow ships CG to a tow hook directly above, would be quite short....... not much more than say 4 feet. I would think correcting for pressures applied at 48� would be well within flight controls to compensate. Constant back pressure could be trimmed out. In the RC world, the tow ships are normally quite stable, as is Glider..........problems arise when too much pilot input is applied on either end of the rope! Guide wires from the top of the rudder fin to the tip of both stabilizer tips could keep the tow rope away from the tows tail feathers.
Just thinking outside the box,
JJ

Has anyone investigated placing the tow hook directly over(or under) the tow planes center of gravity?

I'm trying to envision what that would look like. To be at the CG, there would have to be as much behind and below and ahead and above. How would you rig this without hitting the tail on low or high tow?

Maybe 'over' the CG would eliminate above and below, but still don't see how.

Not seeing how, does not mean there isn't a way, so how do the RC folks do it?

Might have to rig a yolk-type system like the old Blanik L-13 yolk, but installed on the tug end. Model it using a toy Piper Pawnee; tie a string around the outboard strut wing attachment points on both sides (close enough to the CG). Tie the two strings together with a ring in a "Y" well beyond the tail feathers. Attach the tow rope to the ring and voila! If the glider climbs above the Pawnee, the yolk just pivots through the CG, avoiding a tail pull-up.

I thought through the hard stuff, you solve the little details.

I thought through the hard stuff, you solve the little details

Cadd drawings of CG-yolk attachment to discourage tail-lifting by kiting glider.

https://www.dropbox.com/sh/rjcl6hugl...rTU8p2W5a?dl=0

It has been done in Germany during WWII with military gliders. It was called "Hubschlepp". It was tested with a DFS 230 transport glider and a Junkers Ju 87 B-1 as a towplane. The system was very stable, only one of the two pilots had to steer his plane, the other just followed. Climb rate was roughly double that of the normal tow: 5–7 m/s against 2–3 m/s. Service ceiling, autonomy and maximum speed increased also.

https://de.wikipedia.org/wiki/Flugze...epp#Hubschlepp (in German)
See also: Ernst Peter: Der Flugzeugschlepp von den Anfängen bis heute. Motorbuch Verlag Stuttgart, 1981.

How about banning all sideways/aft opening canopies from gliders? An unlocked canopy is a non-event in my LS6 with it's forward hinged canopy. Grobs? Deathtraps!

Or, just ban all canopies, period. Open cockpits are much more relaxing, and there is one less thing to mess up prior to takeoff.

OR, we could switch to using helicopters to aerotow...just put a CG hook on the TOP of the glider, lift vertically to 3000', and cut'em loose. Yee Haw! With a Chinook you could even daisy-chain several gliders and take up the whole club at once - just make sure you release from the bottom up...

Seriously:

1. Replace ALL Schweizer tow hooks with TOST releases (or equivalent) with the release lever close to the throttle. This is a no-brainer.

2. DO NOT TOLERATE ANY out of position/out of view flying by ANY glider pilot. At a minimum, talk to them after a flight with an "incident"; worse case, hand them the rope as soon as they get out of position (within gliding range of the field, of course, if possible).

Kirk
66

"How about banning all sideways/aft opening canopies from gliders? An unlocked canopy is a non-event in my LS6 with it's forward hinged canopy. Grobs? Deathtraps!"

The problem with a side opening canopy is the overwhelming temptation to save the club $6,000 by holding the canopy down. Unfortunately lack of a third hand can result in a glider write-off or worse. Left rudder can get you back a hand for operating the spoilers, but where is this taught?

With a rear opening canopy, it's gone and your only concern is making a survivable landing, with or without glasses.

Grobs are much less vulnerable to mislatching the canopy than L-33s as the housing to receive the pin is substantially thicker making the gap more obvious. L-33s need a feeler gauge to check if the canopy is actually closed.

Howdy all, new here, only second post, and please forgive my bloviating, but this has always been a hot button issue for me. My experience is not as vast as some, but 32 years in aviation, nearly 14,000 hours and 19,000 take offs and landings in everything from Sailplanes, tow planes, single engine, multi-engine land and sea, turboprops, Helo's, and now "Heavy Iron".

I haven't flown sailplanes in, effectively, 2 decades. Did my "return" flight just yesterday.
Disclosure, I am a product of UH and Valley Soaring, with a standard operating procedure of Low Tow.

2 thoughts.

1. My "fear" of High Tow, as both a glider pilot AND as a Tow Pilot, has been a MAJOR factor in my failure to return to the sport sooner, and continues to be a significant deterrent of my potential return. (I feel the same way about Wheel Landings in tail draggers, I know how to high tow and wheel land, just not a fan.)
2. If we instilled the same safety enhancing procedures ("One level of safety")in the sport of Soaring as we do in other aspects of aviation, IE Part 121 or 135, I honestly feel high tow would have been essentially outlawed long ago. I encountered VERY similar attitudes in the skydiving industry where I was working as a chief pilot of a very large jump operation. Outright hostility towards change, even safety enhancing change, was unfortunately the normal attitude. It took my preaching to a group of 200+ skydivers over a PA system, to remind them that continued unsafe behavior would cause them to be nothing more than a huge 12 step meeting with really expensive jet fueled filled lawn ornaments sitting on the airport side of the fence. A drop-zone without its pilot is nothing, same goes for a glider operation without tow pilots.

As UH said early in this thread, over 70,000 essentially trouble free low tows at Valley Soaring over many decades, most with Schweizer tow hooks must say something. Low tow is the standard down in Oz, and apparently a few other places in Europe/Scandinavia according to the gentleman I flew with in the 2-33 yesterday. I honestly know more than a half dozen glider and tow pilots that have left the sport due to local clubs refusing low tow after leaving clubs that did for various reasons like job relocations.

I am convinced low tow is SAFER, more EFFICIENT, and I feel would prevent a vast majority of these types of tragedies. Just adding my opinion to the mix, as well as my condolences to those involved in this tragic accident.

Low tow costs NOTHING to try. When it is done properly, it is FAR easier on the glider pilot AND the tow pilot, and has the amazing side effect of being safer. We must not allow this discussion to diverge down the wrong path. Talking about reinventing the wheel and making wholesale, expensive changes to hardware will not work. When a consistent problem keeps popping up at the airline level, we institute carefully thought out and implemented procedural change first. Changing equipment is horrifyingly expensive, and very time consuming. Procedural changes do not take long. And it usually produces the anticipated result. In my opinion, for what ever it is worth, a simple change to how we do things might produce a significantly lower rate of problems. We did it in the jump flying community. Over the last 20 years ONE MAN, who I am honored to call my friend, created a website, disseminated accident data and proposed solutions to the skydiving industry as it pertained to jump flying. It produced a significant 50% REDUCTION in accidents, and his writings have become policy in over 20 nations around the world to be permitted to operate as a jump pilot. He did all this just by suggesting some new, more thorough, training methods and changing the attitudes of those involved. Even a little.

Change to low tow, make sure students and visiting pilots understand the importance of FLY THE PLANE FIRST. Keep the existing equipment properly maintained, maintain effective training methods and attitudes and make sure they all know open canopies, unlocked spoilers or whatever don't matter when low to the ground. Fly the damn plane first. Deal with the other garbage later.

This reminds me, remember watching R/C gliders do R/C Aero tow? Tow plane had the rope attached on top of the wing on or real close to the CG. The glider flew high tow. Why do you think this is? This is not practical on real aircraft.

Ask yourself, why do most operations here use high tow? Anyone know why? Cause I have no idea. Why do we switch to low tow for cross country tows? I remember hearing people flew high tow because they were afraid if the rope broke near the tow plane on low tow it would somehow fight a 60 mph headwind and wrap itself around the control surfaces. Even my 13 year old mind knew that sounded absolutely absurd. It made no sense as even at 13 I knew enough physics to know that was impossible. I never heard another reason for high tow in all my years.

Sorry for the rant. Condolences to everyone involved.