I don't have a weekend report this week. I've been traveling, and I don't know what happened at Post Mills.
I do have a story, however. I am at the Bermuda High Soaring School near Lancaster, South Carolina. It's a gliders-only operation owned by friends Frank and Jayne Reid. Two days ago, a PW-5 took off with one aileron disconnected. The glider pilot figured out what was wrong after it was too late to release and land straight ahead. Since the glider was controllable on tow, the pilot decided to hang on for some altitude and time to think. After discussing the situation by radio with the tow pilot, the two of them decided to make an approach to a landing while still on tow. They descended at low power setting and full spoilers on a long final approach, and three feet above the ground, the glider released and made a normal landing.
Afterwards, all observers and commenters agreed that it was the right thing to do (to stay on tow). The general consensus is that a stable situation is better than an unpredictable situation.
I wonder what would have been the outcome if this had happened at Post Mills. We don't have radios (not all gliders here have radios, either - they were lucky). Should there be a tow signal for this situation? It seems that this mishap would be more common than a release failure, for which we do have a signal. Definitely something to think about. Comments invited.
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13 comments:
I don't know, the case could be made that flying an approach with a miss rigged glider on tow puts two pilots and two aircraft at risk. At an ever lessening altitude in a maneuver that no one has trained for. What if the loose connection fouled the good connection at 50'? I'm glad this worked out but I say get altitude and get off thus removing the towpilot and towplane from risk. You miss rigged (or didn't properly inspect)your glider, hard cheese, deal with it. Instead of increased radio use I would suggest increased parachute use, be a pilot(or parachutist if it comes to that) of action not talk.
Related info, in the 'I don't want to confirm this for myself category.' I've heard 1-26's fly ok with an aileron disconnected.
I agree with the crowds view on this one. Now if the glider was flopping around like a wet rag I would have released him anyway but with everything being stable I like what they did.
On radios, I like the hand-held FRS or whatever-they-are idea but that won't work in all situations either.
I would have released over the airport at 1500-2000. The glider needs less control input off tow than on. Your roll authority is 1/2 of normal but you don't need all of it fly a pattern. You also have a fully functional rudder.
I also agree that you don't endanger the towpilot this way.
My only real fear would be if the disconnected control would jam, perhaps with full aileron input to one side. If I considered this likely, I would parachute down.
Todd Smith
3S
PS, I hope to see you at wave camp.
That is another factor- talking on a hand held while flying on tow is bad enough, doing that with one aileron on a bumpy day...
Panel mounted radios are out of the PMSC budget for many many years.
For the hand-held radio idea, we could velcro them somewhere and use a lightweight head set with voice activated mic.
See http://tinyurl.com/255puu for
Motorola VOICE-ACTIVATED Headset For Talkabout Radios
Transmit by pressing the Push-to-Talk button on radio or use VOX (voice operated transmission) option for hands-free operation, $11.
Just a thought.
I'd prefer if we don't turn this into a discussion about radios. I'd rather hear more about what people think about the decision to stay on tow.
And I would really like to hear what you think would happen without radio communications. Should there be a new tow signal?
No to a new tow signal. Trying to move the glider around to signal the tow plane with limited control authority is in my opinion asking for trouble. How useful is a one club tow signal. I believe that if the glider is controllable then they should stay on tow to altitude, certainly reasonable to go higher then 3K, release and then land the glider or jump.
Maybe we need an inflight control check(after release) for control failure, we teach one for skydiving students. Something along the lines of 90 degree turns, flight from just above stall(might not want to stall w/compromised controls) to 65/70 and repeat the speed test with the spoilers open.
position summary:
No to a new tow signal.
No to landing on tow w/control failure.
No to a new tow signal, nobody would remember it anyway. Besides, this would be a PIC decision.
Todd said:
"The glider needs less control input off tow than on."
I wonder if this is true in the case of (some sort of) elevator failure. It is conceivable that the towrope contributes to holding the glider's nose up, and that it would not be posssible to hold the nose up in free flight.
(Hi, Todd)
Rick
I read with interest your report on my incident at Bermuda High, and some of the comments. I gather you weren't there so did not have benefit of listening to the radio conversation, but all agreed that it was deliberate with clear concise information flow between the two pilots. I don't however believe some of the comments to your report take into account all of the factors. I take full responsibility for my carelessness of a mis-rigged glider, but I am very comfortable with the decisions made after that and the manner in which they took place. Everything continued to play out so thankfully other options were not needed.
There were two pilots involved and we made decisions together. It wasn't just my decision to stay on tow. When I declared the emergency, Jayne asked what I wanted to do. I indicated to stay on tow, she agreed and climbed to pattern alt close to the field while we evaluated the situation. A short time later we agreed to tow to a landing. A release would have removed all options. If at any time either of us felt uncomfortable we would have gone to option B which was to go to bail out altitude, release and attempt to fly. If not, take a chute ride down. Or in extreme, either of us could release at any time.
I had full aileron authority until well after take off. I then heard a clank behind me, felt the aircraft roll a bit and heard the disconnected control rod slapping around. It was clear in an instant what had occurred. I am also very familiar with the setup on the PW5 and knew the control rod was well constrained in radial movement by the wing root rib. I also ascertained that the aileron was "trailing" in a neutral position very nicely in the slip stream. It didn't take moments before I had worked out control inputs to keep the glider in tow position using the left aileron and rudder. I don't think there was much danger of the aileron fouling, but was on the look out for any indication. That would have changed options.
I do believe I could have released from tow and flown to a landing. The key word here is "believed". I didn't know. What I knew was I had a controllable aircraft on tow.
Keep in mind that as we made our way to long final at pattern altitude a very cautious and controlled exploration of the controllability of flight was made including use of spoilers which would be absolutely necessary to fly on tow back to a landing to keep from over flying the tow plane. I have done cross country tows on aero retrieve with the PW so was well familiar with the need to "dirty up" the sailplane to stay behind the tow plane. I also, with Jayne's knowledge, intentionally flew to some slack rope several times to test controllability in "free flight". We made two left turns and two right turns on tow before committing to final approach. The final was smooth and controlled at all times. Both of us were prepared to release in an instant. I made one final test of controllability well above touch down or runway threshold before we committed. I do not believe the tow plane was in any abnormal jeopardy at any time.
In my various flight reviews, practical test, ab initio training, etc. the double release failure and landing of both aircraft in tandem was briefed. It happened exactly as briefed. Quite frankly it is not a particularly difficult or alarming procedure provided both pilots keep their wits about them. A lesser tow pilot might have caused me concern. Jayne was fantastic and absolutely precise in her flying, putting the tow plane exactly where it needed to be.
As we flew over the field, Jayne held the tow plane high. I dropped to a lower tow position but above the wake. I closed up on the spoilers to go slightly slack rope so the PW was clearly flying on its own and then released and landed. Put the nose wheel down and full brake to a stop. Jayne continued on to fly well clear.
In any case, all options were on the table right down to my release. Any change in any factor would have caused us to re-evaluate. BTW, wind was relatively calm. Had a heavy cross wind been in play, our decisions might have been different.
Their are two lessons that I hope other pilots will take away. The first is that a positive control check is not sufficient. My sailplane passed. It wasn't until aero loads developed sufficiently that the connection came loose. Since the incident, I have ascertained three ways of misconnecting in the tight quarters through the access hatch that this can happen. I will not fly again without another pilot checking my assembly. I am creating a very pointed check list to hand to the checking pilot as a guide on the critical assembly items. For the PW5 - locking tabs out on wing pins, control connections properly made (verified visually not just by feel), locking pins up on control connections, elevator pin locking tab in locked position.
The second lesson is simple enough - fly the airplane. Keep all options available for as long as possible. Think through everything you will need to do. Try to stay ahead of the airplane. Keep cool. Don't rush or commit until you are ready. Jayne was prepared to do another circuit around the pattern if we needed to.
I do not believe what we did could or should be attempted without the pilots being able to fully communicate. Without radios, I think the only option is get off tow and do the best you can. There is too much chance for mis-step. In the no radio case, I think you do put both aircraft and pilots at unacceptable risk.
I hope the above is of some interest to you and your members.
Gary, thank you very much for your story.
Gregg
The pilot was given the choice by the tow pilot ... to try it on his own or come down with me.. I felt the best thing was to come down with me as in a double release failure. I would have never NEVER let him go - unless HE decided it was the best thing for him to do. In the situation of equilibrium such as it was, there was no reason to release him. Chances of a stuck aileron are things you say "what if" ...well...there are too many what ifs to explore and what's the point???
Radios are a necessity in fiber glass "rigged" planes...too many things have happened where a radio was a necessity: "your tail dolly is on"..."your spoilers are open"..... And to the towpilot: "your tail wheel just fell off"...
My two cents: explore the market for used radios. The signal is ok...but nothing can take the place of good communication.
Jayne
This has been a very helpful and useful dialog for me as a student. I've read safety reports from SSA etc of course but this really came home for me. Both because of the quality of the dialog but also because it was relevant as a real world scenario for me.
I hope we see more of this type of exchange here.
-Peter
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