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Excuse me while I turn the short "Always release on Wing Drop" into a long discussion. I least my discussion is long. But like the "Impossible Turn" for power aircraft I suspect the real answer is when you really start to analyze it we find "it Depends" or "when in doubt release" but help me educate myself and others about what is really going on here.
I have been hearing the release immediately on wing drop for over 30 years.. Yet Winch launching almost always becomes part of the conversation almost immediately during the conversations, but I have I don't recall any conversations on Winch vs Aero Tow, or Grass vs Paved launches or even Towplane type (high power vs low power) with respect wing drop on launch, does any of this make a difference? It would seem to me wing wheels vs skids would be a factor as well. I have watched numerous aerotows off of pavement where the wing hits the pavement drags maybe 10 feet at most, and the glider maybe changes heading 10 degrees at most and then the wing comes back up and the glider repositions behind the glider and proceeds on its way. This is usually attributed to the glider hitting the propwash of the towplane. Having nearly a 1000 hours in a glider with wimpy ailerons I have had my share of wing drops under this scenario and never felt it was an issue or any worse than a no wing runner take off. In fact I recall only one glider releasing when the wing dropped under this scenario which then resulted in the wing tip continuing to drag and turn the glider off the runway into a runway light resulting in some leading edge damage to the wing. IMO if he had flown the glider for another second or two it would have been an uneventful launch. But that is just my opinion, he was PIC. I understand Winch launches happen a lot faster with a lot more energy than most (if not all) aerotows and releasing immediately makes sense for Winch Launches. I can also see that when launching off of Non-paved surfaces that releasing immediately on wing ground contact probably makes sense unless perhaps the plane has large wing wheels or it is a very smooth surface. But I have never heard any discussion about that, and It might be a good discussion for those of us that normally aerotow off of paved runways. I also agree that anytime the heading change of the glider exceeds about 10 degrees one should release immediately regardless if the wing touches the ground or not. On narrow runways this should be pretty obvious because anything more than that you are probably going off the runway anyway. but even launching off wide tarmacs or runways one should still release. But in the kind of Launch I do the most, Aerotow off of a paved runway. These are much lower energy than a Winch launch and as a result a wing drop is more likely. if there is very little heading change with the wing drop, Should we really be releasing immediately or should we wait a second or two for the controls to become effective which they nearly always do. Adding more risk factors to consider is it pretty much a given that CG hooks are a higher Risk of Loss of control. Do High power vs Lower power towplanes affect the risk? Which is better or worse? Does holding the tail down (back elevator) during the early part of the takeoff roll change vs raising it early help? Pro. tailwheel will help resist turning tendency, Con, may delay aileron effectiveness. If one is considering not releasing immediately we/they should develop a risk assessment for doing so. What Have I not considered here? |
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On Friday, March 19, 2021 at 8:26:02 PM UTC-4, Brian wrote:
What Have I not considered here? Wing span. :-). T8 |
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On 3/19/2021 8:26 PM, Brian wrote:
Excuse me while I turn the short "Always release on Wing Drop" into a long discussion. I least my discussion is long. But like the "Impossible Turn" for power aircraft I suspect the real answer is when you really start to analyze it we find "it Depends" or "when in doubt release" but help me educate myself and others about what is really going on here. I have been hearing the release immediately on wing drop for over 30 years. Yet Winch launching almost always becomes part of the conversation almost immediately during the conversations, but I have I don't recall any conversations on Winch vs Aero Tow, or Grass vs Paved launches or even Towplane type (high power vs low power) with respect wing drop on launch, does any of this make a difference? It would seem to me wing wheels vs skids would be a factor as well. I have watched numerous aerotows off of pavement where the wing hits the pavement drags maybe 10 feet at most, and the glider maybe changes heading 10 degrees at most and then the wing comes back up and the glider repositions behind the glider and proceeds on its way. This is usually attributed to the glider hitting the propwash of the towplane. Having nearly a 1000 hours in a glider with wimpy ailerons I have had my share of wing drops under this scenario and never felt it was an issue or any worse than a no wing runner take off. In fact I recall only one glider releasing when the wing dropped under this scenario which then resulted in the wing tip continuing to drag and turn the glider off the runway into a runway light resulting in some leading edge damage to the wing. IMO if he had flown the glider for another second or two it would have been an uneventful launch. But that is just my opinion, he was PIC. I understand Winch launches happen a lot faster with a lot more energy than most (if not all) aerotows and releasing immediately makes sense for Winch Launches. I can also see that when launching off of Non-paved surfaces that releasing immediately on wing ground contact probably makes sense unless perhaps the plane has large wing wheels or it is a very smooth surface. But I have never heard any discussion about that, and It might be a good discussion for those of us that normally aerotow off of paved runways. I also agree that anytime the heading change of the glider exceeds about 10 degrees one should release immediately regardless if the wing touches the ground or not. On narrow runways this should be pretty obvious because anything more than that you are probably going off the runway anyway. but even launching off wide tarmacs or runways one should still release. But in the kind of Launch I do the most, Aerotow off of a paved runway. These are much lower energy than a Winch launch and as a result a wing drop is more likely. if there is very little heading change with the wing drop, Should we really be releasing immediately or should we wait a second or two for the controls to become effective which they nearly always do. Adding more risk factors to consider is it pretty much a given that CG hooks are a higher Risk of Loss of control. Do High power vs Lower power towplanes affect the risk? Which is better or worse? Does holding the tail down (back elevator) during the early part of the takeoff roll change vs raising it early help? Pro. tailwheel will help resist turning tendency, Con, may delay aileron effectiveness. If one is considering not releasing immediately we/they should develop a risk assessment for doing so. What Have I not considered here? Brian, there are a lot of factors, including at least: - tip wheels/skids - surface drag - water ballast - tug acceleration - hook location (no, a nose hook will not save your ass, despite proponents) - wind direction and strength - glider type - spoiler and flap setting - dumb luck So... Do you feel lucky??? |
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On Friday, March 19, 2021 at 9:38:22 PM UTC-4, wrote:
On 3/19/2021 8:26 PM, Brian wrote: Excuse me while I turn the short "Always release on Wing Drop" into a long discussion. I least my discussion is long. But like the "Impossible Turn" for power aircraft I suspect the real answer is when you really start to analyze it we find "it Depends" or "when in doubt release" but help me educate myself and others about what is really going on here. I have been hearing the release immediately on wing drop for over 30 years. Yet Winch launching almost always becomes part of the conversation almost immediately during the conversations, but I have I don't recall any conversations on Winch vs Aero Tow, or Grass vs Paved launches or even Towplane type (high power vs low power) with respect wing drop on launch, does any of this make a difference? It would seem to me wing wheels vs skids would be a factor as well. I have watched numerous aerotows off of pavement where the wing hits the pavement drags maybe 10 feet at most, and the glider maybe changes heading 10 degrees at most and then the wing comes back up and the glider repositions behind the glider and proceeds on its way. This is usually attributed to the glider hitting the propwash of the towplane. Having nearly a 1000 hours in a glider with wimpy ailerons I have had my share of wing drops under this scenario and never felt it was an issue or any worse than a no wing runner take off. In fact I recall only one glider releasing when the wing dropped under this scenario which then resulted in the wing tip continuing to drag and turn the glider off the runway into a runway light resulting in some leading edge damage to the wing. IMO if he had flown the glider for another second or two it would have been an uneventful launch. But that is just my opinion, he was PIC. I understand Winch launches happen a lot faster with a lot more energy than most (if not all) aerotows and releasing immediately makes sense for Winch Launches. I can also see that when launching off of Non-paved surfaces that releasing immediately on wing ground contact probably makes sense unless perhaps the plane has large wing wheels or it is a very smooth surface. But I have never heard any discussion about that, and It might be a good discussion for those of us that normally aerotow off of paved runways. I also agree that anytime the heading change of the glider exceeds about 10 degrees one should release immediately regardless if the wing touches the ground or not. On narrow runways this should be pretty obvious because anything more than that you are probably going off the runway anyway. but even launching off wide tarmacs or runways one should still release. But in the kind of Launch I do the most, Aerotow off of a paved runway. These are much lower energy than a Winch launch and as a result a wing drop is more likely. if there is very little heading change with the wing drop, Should we really be releasing immediately or should we wait a second or two for the controls to become effective which they nearly always do. Adding more risk factors to consider is it pretty much a given that CG hooks are a higher Risk of Loss of control. Do High power vs Lower power towplanes affect the risk? Which is better or worse? Does holding the tail down (back elevator) during the early part of the takeoff roll change vs raising it early help? Pro. tailwheel will help resist turning tendency, Con, may delay aileron effectiveness. If one is considering not releasing immediately we/they should develop a risk assessment for doing so. What Have I not considered here? Brian, there are a lot of factors, including at least: - tip wheels/skids - surface drag - water ballast - tug acceleration - hook location (no, a nose hook will not save your ass, despite proponents) - wind direction and strength - glider type - spoiler and flap setting - dumb luck So... Do you feel lucky??? Nose hook may not save your ass but it is adding a corrective factor - with cg hook if the wing cannot be brought up immediately the release is already overdue. |
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@nadler.com wrote:
On 3/19/2021 8:26 PM, Brian wrote: Excuse me while I turn the short "Always release on Wing Drop" into a long discussion. I least my discussion is long. But like the "Impossible Turn" for power aircraft I suspect the real answer is when you really start to analyze it we find "it Depends" or "when in doubt release" but help me educate myself and others about what is really going on here. I have been hearing the release immediately on wing drop for over 30 years. Yet Winch launching almost always becomes part of the conversation almost immediately during the conversations, but I have I don't recall any conversations on Winch vs Aero Tow, or Grass vs Paved launches or even Towplane type (high power vs low power) with respect wing drop on launch, does any of this make a difference? It would seem to me wing wheels vs skids would be a factor as well. I have watched numerous aerotows off of pavement where the wing hits the pavement drags maybe 10 feet at most, and the glider maybe changes heading 10 degrees at most and then the wing comes back up and the glider repositions behind the glider and proceeds on its way. This is usually attributed to the glider hitting the propwash of the towplane. Having nearly a 1000 hours in a glider with wimpy ailerons I have had my share of wing drops under this scenario and never felt it was an issue or any worse than a no wing runner take off. In fact I recall only one glider releasing when the wing dropped under this scenario which then resulted in the wing tip continuing to drag and turn the glider off the runway into a runway light resulting in some leading edge damage to the wing. IMO if he had flown the glider for another second or two it would have been an uneventful launch. But that is just my opinion, he was PIC. I understand Winch launches happen a lot faster with a lot more energy than most (if not all) aerotows and releasing immediately makes sense for Winch Launches. I can also see that when launching off of Non-paved surfaces that releasing immediately on wing ground contact probably makes sense unless perhaps the plane has large wing wheels or it is a very smooth surface. But I have never heard any discussion about that, and It might be a good discussion for those of us that normally aerotow off of paved runways. I also agree that anytime the heading change of the glider exceeds about 10 degrees one should release immediately regardless if the wing touches the ground or not. On narrow runways this should be pretty obvious because anything more than that you are probably going off the runway anyway. but even launching off wide tarmacs or runways one should still release. But in the kind of Launch I do the most, Aerotow off of a paved runway. These are much lower energy than a Winch launch and as a result a wing drop is more likely. if there is very little heading change with the wing drop, Should we really be releasing immediately or should we wait a second or two for the controls to become effective which they nearly always do. Adding more risk factors to consider is it pretty much a given that CG hooks are a higher Risk of Loss of control. Do High power vs Lower power towplanes affect the risk? Which is better or worse? Does holding the tail down (back elevator) during the early part of the takeoff roll change vs raising it early help? Pro. tailwheel will help resist turning tendency, Con, may delay aileron effectiveness. If one is considering not releasing immediately we/they should develop a risk assessment for doing so. What Have I not considered here? Brian, there are a lot of factors, including at least: - tip wheels/skids - surface drag - water ballast - tug acceleration - hook location (no, a nose hook will not save your ass, despite proponents) - wind direction and strength - glider type - spoiler and flap setting - dumb luck So... Do you feel lucky??? So back to my risk assessment...IMO.. - tip wheels/skids - Skids and shorter = increased Risk - surface drag = More Drag = Increased risk - water ballast = Heaver wings = Increased Risk - tug acceleration = I don't know. Once the wing drops, things will happen slower with a low power tug, a high power tug seems like it has more prop wash to cause the wing to drop in the 1st place and the energy in t he system is building faster, so I think I am leaning toward a High Power tug = maybe an increased risk - hook location (no, a nose hook will not save your ass, despite proponents) CG hook = Increased risk. - wind direction and strength = cross winds = increased risk, less headwind = increased risk. - glider type = a consideration for sure but takes some experience to know if higher or lower risk. - spoiler and flap setting = again likely glider dependent but I know a lot of people start with spoilers extended to prevent wing drop. would think less flap would be better. takes some experience to know. - dumb luck - The whole point of taking a hard look at the details., How many increased risked factor might apply. here's a couple more Rope Length = I would think a shorter rope would = increased risk, more propwash to cause drop Brake Capacity = poor braking capacity = increased Risk obstructions to the side of launch area = present = increased Risk |
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Brian wrote on 3/19/2021 8:41 PM:
.... Do you feel lucky??? So back to my risk assessment...IMO.. - tip wheels/skids - Skids and shorter = increased Risk - surface drag = More Drag = Increased risk - water ballast = Heaver wings = Increased Risk - tug acceleration = I don't know. Once the wing drops, things will happen slower with a low power tug, a high power tug seems like it has more prop wash to cause the wing to drop in the 1st place and the energy in t he system is building faster, so I think I am leaning toward a High Power tug = maybe an increased risk - hook location (no, a nose hook will not save your ass, despite proponents) CG hook = Increased risk. - wind direction and strength = cross winds = increased risk, less headwind = increased risk. - glider type = a consideration for sure but takes some experience to know if higher or lower risk. - spoiler and flap setting = again likely glider dependent but I know a lot of people start with spoilers extended to prevent wing drop. would think less flap would be better. takes some experience to know. - dumb luck - The whole point of taking a hard look at the details., How many increased risked factor might apply. here's a couple more Rope Length = I would think a shorter rope would = increased risk, more propwash to cause drop Brake Capacity = poor braking capacity = increased Risk obstructions to the side of launch area = present = increased Risk My experience with aerotows is: -Starting in negative flaps until about 20 knots IAS is better than using positive flaps -Starting with spoilers extended is definitely better(especially noticed with my ASW20C) -Using a nose hook instead of a CG hook is better with a wing runner, definitely better when launching without a wing runner; also, much less likely to run over the rope at the very start. (I had retrofitted my ASW20C with a nose hook, so I could try it both ways) -Winglets are better than no winglets.\ (I noticed that because my ASH26E came without winglets, but I retrofitted them several years later). -A steerable tail wheel is a terrific aid: without one, you are basically ballistic until you have 15+ knots. I suspect many of the start-of-tow accidents would be avoided if the gliders had one. It can also be a real asset in crosswind landings, but that depends a bit on the tailwheel design and your technique. So, what to do: -Every glider can use spoilers at the start, so it's worth investigating that to learn if that will help in your glider. -If you have flaps, find out if negative flaps help -If you don't have a nose hook (or "forward hook" on some Schleicher gliders), see if there is a retrofit for it. -If you were thinking about adding winglets to your glider, you now have another reason to do it. -Good luck finding a steerable tailwheel retrofit, but you can still nag your glider manufacturer about it. -- Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me) - "A Guide to Self-Launching Sailplane Operation" https://sites.google.com/site/motorg...ad-the-guide-1 |
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"What else did I miss?"---the other side of the equation in risk analysis.
What is the worst that can happen if I don't release? vs What is the worst that can happen if I do? There may be a 1-2 second "startle factor" in some cases. So, the decision must be pre-loaded. There is very little cost (usually) to a release. On Saturday, March 20, 2021 at 8:41:52 AM UTC-4, Eric Greenwell wrote: Brian wrote on 3/19/2021 8:41 PM: ... Do you feel lucky??? So back to my risk assessment...IMO.. - tip wheels/skids - Skids and shorter = increased Risk - surface drag = More Drag = Increased risk - water ballast = Heaver wings = Increased Risk - tug acceleration = I don't know. Once the wing drops, things will happen slower with a low power tug, a high power tug seems like it has more prop wash to cause the wing to drop in the 1st place and the energy in t he system is building faster, so I think I am leaning toward a High Power tug = maybe an increased risk - hook location (no, a nose hook will not save your ass, despite proponents) CG hook = Increased risk. - wind direction and strength = cross winds = increased risk, less headwind = increased risk. - glider type = a consideration for sure but takes some experience to know if higher or lower risk. - spoiler and flap setting = again likely glider dependent but I know a lot of people start with spoilers extended to prevent wing drop. would think less flap would be better. takes some experience to know. - dumb luck - The whole point of taking a hard look at the details., How many increased risked factor might apply. here's a couple more Rope Length = I would think a shorter rope would = increased risk, more propwash to cause drop Brake Capacity = poor braking capacity = increased Risk obstructions to the side of launch area = present = increased Risk My experience with aerotows is: -Starting in negative flaps until about 20 knots IAS is better than using positive flaps -Starting with spoilers extended is definitely better(especially noticed with my ASW20C) -Using a nose hook instead of a CG hook is better with a wing runner, definitely better when launching without a wing runner; also, much less likely to run over the rope at the very start. (I had retrofitted my ASW20C with a nose hook, so I could try it both ways) -Winglets are better than no winglets.\ (I noticed that because my ASH26E came without winglets, but I retrofitted them several years later). -A steerable tail wheel is a terrific aid: without one, you are basically ballistic until you have 15+ knots. I suspect many of the start-of-tow accidents would be avoided if the gliders had one. It can also be a real asset in crosswind landings, but that depends a bit on the tailwheel design and your technique. So, what to do: -Every glider can use spoilers at the start, so it's worth investigating that to learn if that will help in your glider. -If you have flaps, find out if negative flaps help -If you don't have a nose hook (or "forward hook" on some Schleicher gliders), see if there is a retrofit for it. -If you were thinking about adding winglets to your glider, you now have another reason to do it. -Good luck finding a steerable tailwheel retrofit, but you can still nag your glider manufacturer about it. -- Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me) - "A Guide to Self-Launching Sailplane Operation" https://sites.google.com/site/motorg...ad-the-guide-1 |
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On 3/20/21 7:52 AM, Hartley Falbaum wrote:
"What else did I miss?"---the other side of the equation in risk analysis. What is the worst that can happen if I don't release? vs What is the worst that can happen if I do? There may be a 1-2 second "startle factor" in some cases. So, the decision must be pre-loaded. There is very little cost (usually) to a release. Kudos to BFC for attempting to take this particular incident/accident/discussion beyond "mere panacea declamations" to which the RAS medium seems (to me, dry chuckle) prone. On the off chance there're some lurkers "somewhat earlier along" the soaring learning curve - as opposed to long-time RAS regulars (which includes me, and who seem to in recent years be hogging the forum ![]() this thread-to-date contains potentially-personally-useful, seriously-good, food for thought. Hartley's "reduction-ad-absurdem" post above is but one example. In my view, "panacea fixes" (should they in fact be viewed within one's mind as such) are too-often a blind alley when it comes to such things as future learning and "properly preparing one's mind" to commit soaring in as personally-healthy a manner as possible. A common example of "panacea thinking" - at least in my part of the Rocky Mountain Front Range west - is close-minded variations of: "I'll be OK height-wise so long as I have X-thousand feet msl at location Y back in the hills". Well, yeah, most of the time, maybe...but how to reconcile that thinking with the thinking inherent within H. Falbaum's hypothetical line of thought? One size "generally" can't *possibly* fit every situation, and it's up to Joe Glider Pilot to decide how best to approach this conundrum. Given the inherent imperfections in humanity - imperfect judgment/skills, lack of omniscience, etc. - while perfection isn't an option, Joe Glider Pilot can still do a whole lot, and go a long way, to avoid known (to those with greater experience & skills) situations/physical-harm/death that *should* be avoidable, given their existing skills/knowledge. - - - - - - Switching here from "Sermon from the Mount" mode to (so I hope) illustrative examples from experience, O'beer thirty, tale-telling mode... Early in my post-1-26, 15-meter glass, "somewhat-nose-hooked", aerotow state, while attempting to take off from a grass strip in the mountains north of Sun Valley, ID, several things made me pre-launch nervous: slight crosswind, new-to-me tug/pilot of unknown provenances, knee-high grass to either side of runway. I and my wing-runner/partner discussed the situation and pre-planned things best we could (both "local strangers" and prolly 200 hours total time each) and off I went. Pulled the plug after an upwind wing drop followed by progressive swerving into-wind along w. failure of the wing to lift. No harm, no foul was the result outside the cockpit; inside the cockpit...not so much. Serious dismay, as I felt that "somehow" I could've done better under existing circumstances. And so it proved on the 2nd launch attempt following further discussion w. my partner *and* the tow-pilot, and some refining of my mental launch go/no-go plan as well as techniques and "overall awarenesses". Zooming ahead mightily through time, in that and two other ships (HP-14 w. "50% nose/CG hook, 15-meter span, no negative flaps, V-tail, tail skid; and 15-meter Zuni *with* negative flaps, "somewhat nose-hooked", heavily-weighted tailwheel) I aborted 1-each aerotow, both times followed by successful launches behind the same tug/pilot. Both were 5,300'msl, summertime, concerning-but-far-less-so than the C-70 experience...because of successfully pre-planned/decided "mental scenario-ing". In both ships, I also made more-than-one (several? many?) no-wing-runner takeoffs entirely w/o incident. Bragging? Not intended as such. Rather trying to illustrate how "preparing one's mind 'properly'" can be, likely *will* be, a good thing for Joe Glider Pilot, if avoiding adrenaline, negative-excitement, and - potentially - accidents, is deemed personally desirable. Other than what I've read on RAS, I know zip about the situation and the pilot in this particular unfortunate - seemingly, avoidable - accident. I wish him a speedy and full recovery and continued good soaring, if he so chooses. And part of this *particular* Joe Glider Pilot would genuinely appreciate hearing from the horse's mouth at some point in the future, by way of refining my mental picture. YMMV, Bob W. |
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On Saturday, 20 March 2021 at 01:38:22 UTC, wrote:
On 3/19/2021 8:26 PM, Brian wrote: Excuse me while I turn the short "Always release on Wing Drop" into a long discussion. I least my discussion is long. But like the "Impossible Turn" for power aircraft I suspect the real answer is when you really start to analyze it we find "it Depends" or "when in doubt release" but help me educate myself and others about what is really going on here. I have been hearing the release immediately on wing drop for over 30 years. Yet Winch launching almost always becomes part of the conversation almost immediately during the conversations, but I have I don't recall any conversations on Winch vs Aero Tow, or Grass vs Paved launches or even Towplane type (high power vs low power) with respect wing drop on launch, does any of this make a difference? It would seem to me wing wheels vs skids would be a factor as well. I have watched numerous aerotows off of pavement where the wing hits the pavement drags maybe 10 feet at most, and the glider maybe changes heading 10 degrees at most and then the wing comes back up and the glider repositions behind the glider and proceeds on its way. This is usually attributed to the glider hitting the propwash of the towplane. Having nearly a 1000 hours in a glider with wimpy ailerons I have had my share of wing drops under this scenario and never felt it was an issue or any worse than a no wing runner take off. In fact I recall only one glider releasing when the wing dropped under this scenario which then resulted in the wing tip continuing to drag and turn the glider off the runway into a runway light resulting in some leading edge damage to the wing. IMO if he had flown the glider for another second or two it would have been an uneventful launch. But that is just my opinion, he was PIC. I understand Winch launches happen a lot faster with a lot more energy than most (if not all) aerotows and releasing immediately makes sense for Winch Launches. I can also see that when launching off of Non-paved surfaces that releasing immediately on wing ground contact probably makes sense unless perhaps the plane has large wing wheels or it is a very smooth surface. But I have never heard any discussion about that, and It might be a good discussion for those of us that normally aerotow off of paved runways. I also agree that anytime the heading change of the glider exceeds about 10 degrees one should release immediately regardless if the wing touches the ground or not. On narrow runways this should be pretty obvious because anything more than that you are probably going off the runway anyway. but even launching off wide tarmacs or runways one should still release. But in the kind of Launch I do the most, Aerotow off of a paved runway. These are much lower energy than a Winch launch and as a result a wing drop is more likely. if there is very little heading change with the wing drop, Should we really be releasing immediately or should we wait a second or two for the controls to become effective which they nearly always do. Adding more risk factors to consider is it pretty much a given that CG hooks are a higher Risk of Loss of control. Do High power vs Lower power towplanes affect the risk? Which is better or worse? Does holding the tail down (back elevator) during the early part of the takeoff roll change vs raising it early help? Pro. tailwheel will help resist turning tendency, Con, may delay aileron effectiveness. If one is considering not releasing immediately we/they should develop a risk assessment for doing so. What Have I not considered here? Brian, there are a lot of factors, including at least: - tip wheels/skids - surface drag - water ballast - tug acceleration - hook location (no, a nose hook will not save your ass, despite proponents) - wind direction and strength - glider type - spoiler and flap setting - dumb luck So... Do you feel lucky??? Tailskid or wheel, and the weight on it Dihedral, if there's a significant crosswind |
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Before a wing tip even touches the ground, any tailwind component counteracts any aerodynamic control input. The more deflection, the more OPPOSITE effect you get, causing pilot-induced problems. (Why is this glider shooting off to the left when I have full right deflections **!!) It can be mistakenly blamed on the wing runner, prop blast, rogue gust, etc. Hang on a split second longer, and you suddenly have positive control, maybe (?), when forward speed overcomes the tailwind. But by then you just scared yourself and innocent people. Neutralizing the controls, or using "opposite" inputs for the brave, until the tailwind vanishes should help.
Better yet, I just avoid any tailwind tow (for multiple good reasons), especially on an unassisted wing-down takeoff. |
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