Eurocopter crash off Queensland north coast
I struggle with the announced inability of a Pilot to apply pedal to the stop if the helicopter is yawing.
That should be a natural response....apply that pedal which is required to stop the yaw.....and if you hit the physical stop and the yaw is continuing.....then you have a bonafide emergency to deal with.
Upon hitting the physical limit of the pedal movement....you would have to assess the situation to determine the factors causing that.....and determine what actions are needed and are possible.
That should be a natural response....apply that pedal which is required to stop the yaw.....and if you hit the physical stop and the yaw is continuing.....then you have a bonafide emergency to deal with.
Upon hitting the physical limit of the pedal movement....you would have to assess the situation to determine the factors causing that.....and determine what actions are needed and are possible.
do you have fenestron experience?
You would be surprised, how many pilots just don't push the pedal to the stop...
Especially, if they come from a normal tail rotor background
I don’t understand that. If the aircraft starts rolling left to the inverted, I’m pretty sure every pilot would have full opposite right stick, or if it pitched vertically down they’d have full aft stick. Why is yaw different?
Why, because with a normal tail rotor you have more or less a straight line between pedal travel and force generated at the tail, while with a fenestron its not only further travel necessary - its also dependent on the speed, cause the aerodynamical fin will take most of the force of the fenestron at speeds above 60 to 70 knots.
That means, that when you slow down, especially under 40 knots, you need to counteract yaw which isn't compensated by the fin anymore with the fenestron.
Ad to that a crosswind component means you need to give a boot full of pedal to stay straight.
It's no witchwork, but you have to know, what you are doing.
If you come from normal tail rotors you need to adopt.
Has not much to do with fenestron vs tail rotor but simply with a relatively low power tail rotor/fenestron… (like an ec120’has…) with both you run out of them at some point. With aircraft with larger fenestrons you hardly notice any difference if any at all between them and a normal tail rotor. Fenestron of an H145 is for example much more powerfull than the tail rotor of its predecessor (BK117 up and including C-2) Even Bell and Leonardo who always argumenten agents “enclosed tail rotors” now introduce them on their Invictus and AW009… Comanche also had one and flew 70kts sideways easily.
Well 212man,
Why, because with a normal tail rotor you have more or less a straight line between pedal travel and force generated at the tail, while with a fenestron its not only further travel necessary - its also dependent on the speed, cause the aerodynamical fin will take most of the force of the fenestron at speeds above 60 to 70 knots.
That means, that when you slow down, especially under 40 knots, you need to counteract yaw which isn't compensated by the fin anymore with the fenestron.
Ad to that a crosswind component means you need to give a boot full of pedal to stay straight.
It's no witchwork, but you have to know, what you are doing.
If you come from normal tail rotors you need to adopt.
Why, because with a normal tail rotor you have more or less a straight line between pedal travel and force generated at the tail, while with a fenestron its not only further travel necessary - its also dependent on the speed, cause the aerodynamical fin will take most of the force of the fenestron at speeds above 60 to 70 knots.
That means, that when you slow down, especially under 40 knots, you need to counteract yaw which isn't compensated by the fin anymore with the fenestron.
Ad to that a crosswind component means you need to give a boot full of pedal to stay straight.
It's no witchwork, but you have to know, what you are doing.
If you come from normal tail rotors you need to adopt.
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One wonders how many hours is appropriate to achieve reliably adequate skill levels under all conditions when making a "fenestron transition".
With all my time in the R22 and R44, when I jumped into the G2 for the first (and so far only) time, the instructor warned me some profanity was likely to be spewing from my mouth. Flying the pattern and autos were fine, but hover patterns in 10 gust 20 did have me cursing some! After two hours I'd say I only had the most rudimentary mastery of the system. Not sure 10 hours would have seen me supremely confident in all conditions.
With all my time in the R22 and R44, when I jumped into the G2 for the first (and so far only) time, the instructor warned me some profanity was likely to be spewing from my mouth. Flying the pattern and autos were fine, but hover patterns in 10 gust 20 did have me cursing some! After two hours I'd say I only had the most rudimentary mastery of the system. Not sure 10 hours would have seen me supremely confident in all conditions.
I don’t understand that. If the aircraft starts rolling left to the inverted, I’m pretty sure every pilot would have full opposite right stick, or if it pitched vertically down they’d have full aft stick. Why is yaw different?
Why should you have had to state the bleeding obvious.
For our Fenstrom Expert....would it surprise him to think that even the venerable old Huey had a Tail Fin and Synch Elevators for a reasons besides being a. neat place to hang a Non-Fenstron Tail Rotor?
Yes...Fenstrons are different than legacy tail rotors but then so are NOTAR's and oddly enough the Kaman Husky really is different as well....yet it has tail fins.
But in everyone of them....if the nose is going in a direction you do not wish it to go....you push the opposite Pedal until the yaw stops....or you run out of pedal travel which ever happens first.
I struggle with the announced inability of a Pilot to apply pedal to the stop if the helicopter is yawing.
That should be a natural response....apply that pedal which is required to stop the yaw.....and if you hit the physical stop and the yaw is continuing.....then you have a bonafide emergency to deal with.
Upon hitting the physical limit of the pedal movement....you would have to assess the situation to determine the factors causing that.....and determine what actions are needed and are possible.
That should be a natural response....apply that pedal which is required to stop the yaw.....and if you hit the physical stop and the yaw is continuing.....then you have a bonafide emergency to deal with.
Upon hitting the physical limit of the pedal movement....you would have to assess the situation to determine the factors causing that.....and determine what actions are needed and are possible.
Thinking it *was* an emergency (eg loss of TR control) those mishap pilots then “trying to determine the factors causing that” (as you wrote) then get off that presumed ‘ineffective’ pedal, maybe roll of the throttle or try other crazy things that then cause the crash.
When this yaw problem develops (ie in the hover, or when transitioning from slow forward flight to hover) we are (in a H120, Gazelle or Guimbal anyway) already close to max power. Again, pilots primary fear is to avoid over torquing that engine by commanding much of that power sapping Fenestron in the back.
What is required here, namely to give full right boot, immediately and without delay, and to stand on that pedal stop until the rotation stops, comes as extremely counter-intuitive to most pilots, for the above mentioned reason.
This is the reason for many entirely avoidable accidents that are wrongly blamed on the lack of tail rotor effectiveness of the Fenestron.
I have found the Fenestron on the EC120 to be very effective, but obviously it uses a lot of power. A trait of Fenestrons in the hover/low speed regimes.
In one flying roll, I would swap during the day between an AS350 and the EC120. The difference in required peddle movement was extreme.
Many people falsely confuse the required peddle travel with ineffectiveness. And some don’t use the unfamiliarly large full travel when required.
As an aside: I have witnessed poor piloting technique result in over torque events. (Basically allowing a yaw to develop, often associated with sudden increase in power, then finally correcting with sufficient peddle and the associated increase in power demand.)
In one flying roll, I would swap during the day between an AS350 and the EC120. The difference in required peddle movement was extreme.
Many people falsely confuse the required peddle travel with ineffectiveness. And some don’t use the unfamiliarly large full travel when required.
As an aside: I have witnessed poor piloting technique result in over torque events. (Basically allowing a yaw to develop, often associated with sudden increase in power, then finally correcting with sufficient peddle and the associated increase in power demand.)
Can somebody tell me if I'm missing something here. We have a pilot new to type with a design feature he has limited experience with, flying a heavy aircraft with an engine that is running out of puff, landing in a tight spot and out of the wind, surrounded by water with nowhere else to go, carrying tourists who don't understand English. And then, when things turned to worms, he didn't put in full right pedal to arrest an un-commanded yaw. And then, in all that excitement failed to pop the emergency floats when splashdown was imminent. I mean, did he give himself any chance of ever pulling this off safely? We as a pilot community seem to be doing inexplicable stuff that wrecks otherwise perfectly serviceable helicopters time and time again.
I mean, did he give himself any chance of ever pulling this off safely? We as a pilot community seem to be doing inexplicable stuff that wrecks otherwise perfectly serviceable helicopters time and time again
Pertinent quotes from the report.
the helicopter manufacturer advised against conducting left turns at low airspeed, especially in performance limited conditions (and what was this lad doing? Complying with company SOP)
although legally qualified to conduct the flight, the pilot was inexperienced on the helicopter type, and the opportunity provided for consolidating their skills on the helicopter type was limited (do we say its his fault for the limited type experience?)
although legally qualified to conduct the flight, the pilot was inexperienced on the helicopter type, and the opportunity provided for consolidating their skills on the helicopter type was limited (do we say its his fault for the limited type experience?)
Not the 'system' per se, just piss poor oversight by his employer.
The legal minimums are too low and it is his employer's responsibility to make sure he is competent and proficient enough to fly pax in that aircraft.
Perhaps they didn't understand the differences between TR and Fenestron either.
The legal minimums are too low and it is his employer's responsibility to make sure he is competent and proficient enough to fly pax in that aircraft.
Perhaps they didn't understand the differences between TR and Fenestron either.
That doesn’t work like this neither. To the opposite, new civilian pilots are first and foremost taught to not over control and to avoid harsh, rapid or abrupt control inputs. We are taught to “ride it out”, in particular to be aware of mast bumping in turbulence (which requires the opposite of what you say, you must lean into the bank, not fight it with opposing cyclic) etc pp.
When this yaw problem develops (ie in the hover, or when transitioning from slow forward flight to hover) we are (in a H120, Gazelle or Guimbal anyway) already close to max power. Again, pilots primary fear is to avoid over torquing that engine by commanding much of that power sapping Fenestron in the back.
What is required here, namely to give full right boot, immediately and without delay, and to stand on that pedal stop until the rotation stops, comes as extremely counter-intuitive to most pilots, for the above mentioned reason.
This is the reason for many entirely avoidable accidents that are wrongly blamed on the lack of tail rotor effectiveness of the Fenestron.
When this yaw problem develops (ie in the hover, or when transitioning from slow forward flight to hover) we are (in a H120, Gazelle or Guimbal anyway) already close to max power. Again, pilots primary fear is to avoid over torquing that engine by commanding much of that power sapping Fenestron in the back.
What is required here, namely to give full right boot, immediately and without delay, and to stand on that pedal stop until the rotation stops, comes as extremely counter-intuitive to most pilots, for the above mentioned reason.
This is the reason for many entirely avoidable accidents that are wrongly blamed on the lack of tail rotor effectiveness of the Fenestron.
Sure, send him off as a Cat D for the first 25 hours at significantly reduced weights with cross-wind limitations, then if he hasn't bent anything after that time bump him up to a Cat C. etc etc. But I bet the boss would not be happy going out with less than a full load of passengers. I've got a hunch I know what was going through the pilot's mind when he noticed that caution light on just before landing. I 'aint gonna land with a caution light on and not being allowed to take-off again, causing the boss a headache to get a defect fixed on a helicopter parked out on a pontoon. Boss 'aint gonna be happy with me if I do that. Well, the boss gonna be more unhappy dropping it in the tide, failing to pop the floats and drowns two passengers. All because of second guessing what the boss might think about stranding his helicopter out on a pontoon.
Do. not feel like you are the only occupant of that parallel universe 212man.
In the past couple of days I have been fortunate to learn a lot here in this forum than during my career spent flying helicopters in just about every part of the industry there is....and in more than a few kinds, types, and. models of helicopter.
That is the benefit of this forum....especially when that which is being learned is valid, useful, and accurate.
That is the shortcoming of that parallel universe we slip into at times....where it's conventional wisdom is contrary to the Real World we actually live in.
The danger is there are some through their newness cannot discern the difference and might fall pray to the teachings of that parallel universe.
In the past couple of days I have been fortunate to learn a lot here in this forum than during my career spent flying helicopters in just about every part of the industry there is....and in more than a few kinds, types, and. models of helicopter.
That is the benefit of this forum....especially when that which is being learned is valid, useful, and accurate.
That is the shortcoming of that parallel universe we slip into at times....where it's conventional wisdom is contrary to the Real World we actually live in.
The danger is there are some through their newness cannot discern the difference and might fall pray to the teachings of that parallel universe.
I’m not sure how much “Time on Type” is required before applying right peddle* is the response to left yaw/applying power in a “French” machine.
*(in sufficient amount, ASAP, up to the stop if required)
*(in sufficient amount, ASAP, up to the stop if required)
I’m not sure how much “Time on Type” is required before applying right peddle* is the response to left yaw