Chop tail off in the hover??
Thread Starter
Chop tail off in the hover??
Left and right yaw followed by nose up and down and then tail chopped. That’s a dramatic sequence from what I understand to be an OGE, albeit low level, hover. Serious over controlling or could turbulence from the tree tops be wholly responsible?
https://atlantic.ctvnews.ca/pilot-de...rash-1.5343237
https://atlantic.ctvnews.ca/pilot-de...rash-1.5343237
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The report is here
https://www.tsb.gc.ca/eng/rapports-r.../a20a0027.html
They've highlighted LTE, presumably as they cleared the trees tail rotor entered the vortex from the main rotor blades
https://www.tsb.gc.ca/eng/rapports-r.../a20a0027.html
They've highlighted LTE, presumably as they cleared the trees tail rotor entered the vortex from the main rotor blades
Nah, TTRW < 150. On type < 100. Nil HRS past 90 days.
I wouldn’t say he ”forgot” how to fly because at that hours he hadn’t ‘learned’ yet to fly.
Plus all the other signs of attitudinal incompetence: no medical (3 yrs expired) no flight log entries, ...
I wouldn’t say he ”forgot” how to fly because at that hours he hadn’t ‘learned’ yet to fly.
Plus all the other signs of attitudinal incompetence: no medical (3 yrs expired) no flight log entries, ...
Avoid imitations
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Rules, regulations and common sense obviously didn’t apply to this pilot.
His medical was two and a half years out of date so he was unlicensed and presumably therefore uninsured. I feel sorry for his unknowing passengers.
His medical was two and a half years out of date so he was unlicensed and presumably therefore uninsured. I feel sorry for his unknowing passengers.
The report states he was only 130 lbs under gross max weight at the time of the accident and this was when he was going for a refuel - what was his take-off weight when they started the trip then? Full fuel (110 litres)is just over 200lbs.
130lbs is only 5% below max gross and, adding in the relatively high temperature, he will have been working the aircraft quite hard to get into an OGE hover, let alone then climb vertically.
I wouldn't be surprised if he drooped the Nr trying to lift out of the confined area, slowing down the TR by default and reducing its effectiveness. Then, panic at the prospect of a non-existent TR malfunction led to some serious overcontrolling.
A very inexperienced pilot trying to do things way beyond his capabilities - again!
Shame the TSB muddies the waters by banging on about LTE - this clearly wasn't.
130lbs is only 5% below max gross and, adding in the relatively high temperature, he will have been working the aircraft quite hard to get into an OGE hover, let alone then climb vertically.
I wouldn't be surprised if he drooped the Nr trying to lift out of the confined area, slowing down the TR by default and reducing its effectiveness. Then, panic at the prospect of a non-existent TR malfunction led to some serious overcontrolling.
A very inexperienced pilot trying to do things way beyond his capabilities - again!
Shame the TSB muddies the waters by banging on about LTE - this clearly wasn't.
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It was not hot at 23.6C (74.5F). It was not high, CCW5 is 350 ft MSL. Weight is 2370. That is well within the OGE hover performance limits of the R44.
Full fuel is 47.7 USG or 180 liters assuming bladder tanks (it would be a hair more with the old tanks). Assuming there was room in the tanks for all of the 130lbs available that would be 21.6 gallons, or almost half tanks. However those numbers are probably meaningless because the report does not discuss the fuel state of the aircraft. But theoretically if he added 20 gallons that would give him well over an hour of additional flight time. Conservative planning for an R44 RII at max. gross, near sea level, 90KN, is about 15 gal/hr. That might have been exactly what he was seeking.
The weather conditions including winds were well within the limits of the machine. The max. performance take-off at max. gross would have required maximum pilot effort, though, if the trees are as high as reported.
It is unfortunately that this pilot did not choose to come in over the water above ETL with the wind on his right. Or make an approach to the water into the wind and hover taxi with a right crosswind up onto the paved ramp. Perhaps the paved ramp was full, or that he was untrained/unfamiliar with crosswind landings, or the fuel drums were in the confined area. Either way, a little unanticipated yaw, which is certainly possible, should not have lead to such wild pilot-induced oscillations that the tail was cut off, but no doubt I state the obvious.
Full fuel is 47.7 USG or 180 liters assuming bladder tanks (it would be a hair more with the old tanks). Assuming there was room in the tanks for all of the 130lbs available that would be 21.6 gallons, or almost half tanks. However those numbers are probably meaningless because the report does not discuss the fuel state of the aircraft. But theoretically if he added 20 gallons that would give him well over an hour of additional flight time. Conservative planning for an R44 RII at max. gross, near sea level, 90KN, is about 15 gal/hr. That might have been exactly what he was seeking.
The weather conditions including winds were well within the limits of the machine. The max. performance take-off at max. gross would have required maximum pilot effort, though, if the trees are as high as reported.
It is unfortunately that this pilot did not choose to come in over the water above ETL with the wind on his right. Or make an approach to the water into the wind and hover taxi with a right crosswind up onto the paved ramp. Perhaps the paved ramp was full, or that he was untrained/unfamiliar with crosswind landings, or the fuel drums were in the confined area. Either way, a little unanticipated yaw, which is certainly possible, should not have lead to such wild pilot-induced oscillations that the tail was cut off, but no doubt I state the obvious.
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Just because the manual says the aircraft can doesnt mean your aircraft can. Please remember that the manual is derived from test pilots using a new helicopter with perfectly clean blades and a brand new engine, there ability is obviously beyond the majority of pilots with the manufacturer trying to make his machine's performance look really good
aa777888 - when you say 'well within' you should qualify that with 'inside the limits of the performance graphs' since you can't tell how much spare performance there might or might not be from the graph, only that you reach the max gross weight line before you hit temperature or DA limits.
Just having OGE performance isn't enough for proper confined area operations like this with tall trees - you need to have a thrust margin of at least 5% and ideally 10% to allow for the manoeuvring and any turbulence/wind shear/recirculation.
My point about the fuel - and I took the 110litre fuel capacity from the Robinson site without realising there was an aux tank giving 180 - was that to get to where they planned to refuel, they would have used quite a lot and in all likelihood got airborne from Reeds Pond in excess of gross weight. It adds to the expired medical in terms of attitude to aviation.
Just having OGE performance isn't enough for proper confined area operations like this with tall trees - you need to have a thrust margin of at least 5% and ideally 10% to allow for the manoeuvring and any turbulence/wind shear/recirculation.
My point about the fuel - and I took the 110litre fuel capacity from the Robinson site without realising there was an aux tank giving 180 - was that to get to where they planned to refuel, they would have used quite a lot and in all likelihood got airborne from Reeds Pond in excess of gross weight. It adds to the expired medical in terms of attitude to aviation.
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Originally Posted by [email protected]
aa777888 - when you say 'well within' you should qualify that with 'inside the limits of the performance graphs' since you can't tell how much spare performance there might or might not be from the graph, only that you reach the max gross weight line before you hit temperature or DA limits.
Just having OGE performance isn't enough for proper confined area operations like this with tall trees - you need to have a thrust margin of at least 5% and ideally 10% to allow for the manoeuvring and any turbulence/wind shear/recirculation.
My point about the fuel - and I took the 110litre fuel capacity from the Robinson site without realising there was an aux tank giving 180 - was that to get to where they planned to refuel, they would have used quite a lot and in all likelihood got airborne from Reeds Pond in excess of gross weight. It adds to the expired medical in terms of attitude to aviation.
Regardless, one cannot but agree that there was a significant lack of airmanship demonstrated.
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Lazy feet and probably looking at the trees, then possibly gripping the throttle too tightly. With that kind of wind, weight and altitude, the 44 shouldn’t end up the way it did.
The performance charts I'm familiar with are always based on a zero engine. If you have a positive margin engine the chart will also accommodate this. If you have less than a zero engine you're off the chart, you can't fly, and maintenance is required. But that's for turbine engines. I don't know if engine trend monitoring is done on piston engines, or whether performance charts take into account the performance margin of the piston engine.
How about this: the aircraft was capable of an OGE hover per the POH at approx. 4800 ft pressure altitude under the stated conditions, but it was landing at an altitude of 350 MSL. In my book that is "well within", others may have a different opinion.
If you were doing a long transit like that in uncertain weather conditions, wouldn't you fill it to full (if you could keep within max gross). The report doesn't mention previous refuel stops but they had to go beyond where they originally planned to refuel so the chances of it being quite empty are higher and may explain why he chose to try and get in where he did.
It would be interesting to know if he did any pre-flight performance planning.
Poor airmanship, poor decision making and ultimately poor handling are the causes here - an inexperienced pilot biting off more than he can chew.
Military turbines have a Power Performance Indicator graph (PPI) and on the Sea King, the performance graphs were based on 94% PPI so as long as your engines were better than that, you were on the safe side of the line - very important for prolonged high hover work when winching.
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Originally Posted by [email protected]
But you don't know how far within and what level of power margin it gives you - that is my point. Just having OGE performance isn't enough for confined area work. And his DA was about 1200'.
If you were doing a long transit like that in uncertain weather conditions, wouldn't you fill it to full (if you could keep within max gross). The report doesn't mention previous refuel stops but they had to go beyond where they originally planned to refuel so the chances of it being quite empty are higher and may explain why he chose to try and get in where he did.
Poor airmanship, poor decision making and ultimately poor handling are the causes here - an inexperienced pilot biting off more than he can chew.