Engine out.....
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Engine out.....
Hi Folks,
Has anyone performed an autorotation after an engine out with a light helicopter close to max.MTOW and realised that; what was executed during practise sessions (ie low MTOW) has very little resemblence to the actual thing in regards to overall picture and execution/landing?
Is it possible not to have any( or very low) Rrpm left once contact is made at the completion (ie landing) of a real autorotation?
Fly safe.
[ 03 December 2001: Message edited by: Nomads ]
Has anyone performed an autorotation after an engine out with a light helicopter close to max.MTOW and realised that; what was executed during practise sessions (ie low MTOW) has very little resemblence to the actual thing in regards to overall picture and execution/landing?
Is it possible not to have any( or very low) Rrpm left once contact is made at the completion (ie landing) of a real autorotation?
Fly safe.
[ 03 December 2001: Message edited by: Nomads ]
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More mass - more energy for the auto. Less juice left for 'cushioning' touch down. Keep some ETL for longer lasting happiness. Watch twin engine simulation of EOL and ask 'How different would that be if it was for real?'
(Ed for spelling - not that I normally notice)
[ 03 December 2001: Message edited by: JoePilot ]
(Ed for spelling - not that I normally notice)
[ 03 December 2001: Message edited by: JoePilot ]
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Simulators are the only answer to safely practicing autos at high AUW. To do it otherwise would be unwise. Even with the engine running the result is not realistic as some residual power is transfered to the drive train. Pity sims are not readily available for light singles. Cheers.
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Thanks JP & Max,
Sometime ago, I think it was a R&W issue early 1999 there was an article about an instructor who had made over 5000 practice auto´s, then the real one occured and he bent the aircraft badly due to the fact that an real auto was substantially different to the practised ones in regards that, in this instance, an Alison 250 still some power provides to the rotorsystem in a practise auto, sufficiently to make a difference...?
Sometime ago, I think it was a R&W issue early 1999 there was an article about an instructor who had made over 5000 practice auto´s, then the real one occured and he bent the aircraft badly due to the fact that an real auto was substantially different to the practised ones in regards that, in this instance, an Alison 250 still some power provides to the rotorsystem in a practise auto, sufficiently to make a difference...?
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Hi Nomads
R22 max weight, 1600ft and take out eng for Auto all the way down to gently caress mother earth,this was done by moi, at Sherburn in Elmet North Yorshire, last February whilst on my yearly test, the only time I felt a little unsure was around the 30ft mark, but after a lot of hauling back on the stick and keeping eveything steady we did a nice sort of jump of the bottom step sort of landing plus a little run on, main rotor on the R22 lose's energy very very quickly but at that point you are only a few feet from the brown stuff, with the way the CFi did the set up he remarked after that it was a lot like that when the thing really goes quiet, but after another one I felt a little more happy at my survivability in Mr Robbies pet bird, I try to have a mock auto to 300ft recovery at least every 6 weeks, might sound a little over the top when you listen to others but at least I feel happy doing them!
R22 max weight, 1600ft and take out eng for Auto all the way down to gently caress mother earth,this was done by moi, at Sherburn in Elmet North Yorshire, last February whilst on my yearly test, the only time I felt a little unsure was around the 30ft mark, but after a lot of hauling back on the stick and keeping eveything steady we did a nice sort of jump of the bottom step sort of landing plus a little run on, main rotor on the R22 lose's energy very very quickly but at that point you are only a few feet from the brown stuff, with the way the CFi did the set up he remarked after that it was a lot like that when the thing really goes quiet, but after another one I felt a little more happy at my survivability in Mr Robbies pet bird, I try to have a mock auto to 300ft recovery at least every 6 weeks, might sound a little over the top when you listen to others but at least I feel happy doing them!
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Doesn't surprise me to hear someone who has done many practice autos has problems with a real one.
The way I've seen autos taught is that it's a technique. That's not innacurate, but it is incomplete. The awareness of the helicopter's performance is as important as the technique.
When flying, you should always consider things like the weight, altitude, landing area altitude, etc. not just for flight performance but also in case of emergencies.
If you're very experienced at practicing, then that is the mind set you will be in when you do it for real.
When it comes down to it, the auto will save me and my pax and hopefully the airframe.
The way I've seen autos taught is that it's a technique. That's not innacurate, but it is incomplete. The awareness of the helicopter's performance is as important as the technique.
When flying, you should always consider things like the weight, altitude, landing area altitude, etc. not just for flight performance but also in case of emergencies.
If you're very experienced at practicing, then that is the mind set you will be in when you do it for real.
When it comes down to it, the auto will save me and my pax and hopefully the airframe.
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Assuming that the instructor / check pilot is comfortable with the process why wouldn’t you do full on autorotation landings.
On the civilian side, while insurance maybe a factor in some situations, a distinction should probably be made between ‘training only’ and more ‘operational’ endeavors. Ab-initio training does have somewhat higher risks due to the experience levels of both the checker and the checkee. There is a significant difference in comfort level in doing this exercise between a, say, 600 hour instructor and a 10,000 company check pilot.
I haven’t flown a type in which I have not been ‘treated’
to “full-ons” (both day and night - if appropriate). It has gone “very quiet” in a Bell 47, Bell 206A and S-58. Incidentally, all over water!
The JetDanger episode is a good example why you should go to the surface. A JetRanger on floats and fairly heavy descends ‘quickly’ to say the least. Check ride a month earlier had been on floats but pretty light - half tank plus checker and checkee - with a 20kt wind.
Engine quit
while I was flying near the Labrador coast with two rock-doctors and a bunch of ‘samples’ on board so we were not ‘light’. I turned for the water and did the usual drills. On crossing the shore it all started to unravel as the water was almost flat calm, essentially glassy, fortunately I was paralleling the shore so had some horizon when I pulled pitch. I hit a little harder than I expected but I was pretty good - no additional damage.
When I retuned the radio - HF - and called the base, everyone when “Holy S***, it is for real.” As my voice was high pitched and a couple of decibel higher; my initial call had been disregarded as someone keying the mike while practicing and auto on his way home and without pax - allowed - with pax - not allowed.
I don’t attribute the voice in anyway to ‘super-coolness’
on my part but to absolute confidence in what was about to happen because I had done it all before.
A good landing is one that lets you fly again; a great landing is one that lets the aircraft fly again. If insurance is the arguement against doing full-ons; how many that should have been great landings ended up as something less because of lack of complete training?
On the civilian side, while insurance maybe a factor in some situations, a distinction should probably be made between ‘training only’ and more ‘operational’ endeavors. Ab-initio training does have somewhat higher risks due to the experience levels of both the checker and the checkee. There is a significant difference in comfort level in doing this exercise between a, say, 600 hour instructor and a 10,000 company check pilot.
I haven’t flown a type in which I have not been ‘treated’
to “full-ons” (both day and night - if appropriate). It has gone “very quiet” in a Bell 47, Bell 206A and S-58. Incidentally, all over water!The JetDanger episode is a good example why you should go to the surface. A JetRanger on floats and fairly heavy descends ‘quickly’ to say the least. Check ride a month earlier had been on floats but pretty light - half tank plus checker and checkee - with a 20kt wind.
Engine quit
while I was flying near the Labrador coast with two rock-doctors and a bunch of ‘samples’ on board so we were not ‘light’. I turned for the water and did the usual drills. On crossing the shore it all started to unravel as the water was almost flat calm, essentially glassy, fortunately I was paralleling the shore so had some horizon when I pulled pitch. I hit a little harder than I expected but I was pretty good - no additional damage.When I retuned the radio - HF - and called the base, everyone when “Holy S***, it is for real.” As my voice was high pitched and a couple of decibel higher; my initial call had been disregarded as someone keying the mike while practicing and auto on his way home and without pax - allowed - with pax - not allowed.
I don’t attribute the voice in anyway to ‘super-coolness’
on my part but to absolute confidence in what was about to happen because I had done it all before.A good landing is one that lets you fly again; a great landing is one that lets the aircraft fly again. If insurance is the arguement against doing full-ons; how many that should have been great landings ended up as something less because of lack of complete training?
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My inadvertant full down last week made me realize:
A. That as Heedm says, if you practice enough, the mindset is there for when it really happens.
That in itself will start you upon the path to a successful outcome IMO.
B. And going more on Heedm again, that hey, my first priority is to myself and pax, don't care about the machine after that point, so to speak.
Someone said (somewhere) that you have a bond (trust) with your machine, when the engine dies, hey, it broke that bond, so don't be making maneuvers to save the machine, save your life FIRST. Know what I mean? All things being equal you can replace a heli ...
C. That I could do one!
Now that that experience has been afforded me, I no longer worry (as much) as to what one would be like, etc. (don't read into this statement, I'm still low time, and don't want to repeat the actions that got me there in the first place!
)
A. That as Heedm says, if you practice enough, the mindset is there for when it really happens.
That in itself will start you upon the path to a successful outcome IMO.
B. And going more on Heedm again, that hey, my first priority is to myself and pax, don't care about the machine after that point, so to speak.
Someone said (somewhere) that you have a bond (trust) with your machine, when the engine dies, hey, it broke that bond, so don't be making maneuvers to save the machine, save your life FIRST. Know what I mean? All things being equal you can replace a heli ...
C. That I could do one!
Now that that experience has been afforded me, I no longer worry (as much) as to what one would be like, etc. (don't read into this statement, I'm still low time, and don't want to repeat the actions that got me there in the first place!
)
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Max Ng
We may have a similar screen name dut we are worlds apart on this topic.
At ground ilde position on the 206 Nr is aproximatly 45%-50% so when executing a EOL and the throttle is closed to ground idle position the rotor rpm on touchdown would still be adbove this figure and therefore any assistance from the engine would be negligible to say the least.
AS for practising in a sim I sorry but the very best sim cannot replicate the last 100 ft with any realism. There is no substitute for a EOL flown by the trainee when in the company and under the full control of a experienced and competant instructor. We have started to suffer the effects of low time instructors who themselves have not the confidance or the ability to pass on this flying manoeuvre safely.
This will no doubt stir a few people but I feel very strongly that if you are flying around carrying pax and you feel that if the engine stopped the ensueing forced landing would be a bit of a lottery result then get another job.
I ask all of you who feel unsure about you capability in this manoeuvre find yourself a high time and respected trainer to sit with you for a few EOL,s and the technique will be quickly learnt.
We may have a similar screen name dut we are worlds apart on this topic.
At ground ilde position on the 206 Nr is aproximatly 45%-50% so when executing a EOL and the throttle is closed to ground idle position the rotor rpm on touchdown would still be adbove this figure and therefore any assistance from the engine would be negligible to say the least.
AS for practising in a sim I sorry but the very best sim cannot replicate the last 100 ft with any realism. There is no substitute for a EOL flown by the trainee when in the company and under the full control of a experienced and competant instructor. We have started to suffer the effects of low time instructors who themselves have not the confidance or the ability to pass on this flying manoeuvre safely.
This will no doubt stir a few people but I feel very strongly that if you are flying around carrying pax and you feel that if the engine stopped the ensueing forced landing would be a bit of a lottery result then get another job.
I ask all of you who feel unsure about you capability in this manoeuvre find yourself a high time and respected trainer to sit with you for a few EOL,s and the technique will be quickly learnt.
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MaxNg,
Unfortunately, you are not correct. In the UK prior to JAR-FCL, it was a requirement for commercial pilots that S/E base checks included an EOL at 90% MAUW. this has been deleted from the requirements under JAR-FCL (the 90% bit that is). This is one of a number of retrograde steps, resulting from a committee of civil servants writing the requirements and not helicopter pilots. Some TREs still use 90% but it is not a requirement anymore which is a shame.
Unfortunately, you are not correct. In the UK prior to JAR-FCL, it was a requirement for commercial pilots that S/E base checks included an EOL at 90% MAUW. this has been deleted from the requirements under JAR-FCL (the 90% bit that is). This is one of a number of retrograde steps, resulting from a committee of civil servants writing the requirements and not helicopter pilots. Some TREs still use 90% but it is not a requirement anymore which is a shame.
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Sorry; but I don't see that your "civil servants" are necessarily far off the mark.
Shouldn't the check ride 'situation' and the approval be at he discretion of the check pilot.
Let me see: a check ride at 90-95% MAUW at say, 250'ASL (where I live) and OAT -5 to -10 'proves' competency. Now take the same helicopter and a couple of months later, move it to 3000', put it on floats, OAT +25 drop 100 kg of payload; you now have a different animal and the MAUW 'demonstration' proves SQUAT. Density altitude is much more of a killer than a couple of hundred kilos.
My example is not untypical of Canada and I would assume that it would also apply across Europe.
Shouldn't the check ride 'situation' and the approval be at he discretion of the check pilot.
Let me see: a check ride at 90-95% MAUW at say, 250'ASL (where I live) and OAT -5 to -10 'proves' competency. Now take the same helicopter and a couple of months later, move it to 3000', put it on floats, OAT +25 drop 100 kg of payload; you now have a different animal and the MAUW 'demonstration' proves SQUAT. Density altitude is much more of a killer than a couple of hundred kilos.
My example is not untypical of Canada and I would assume that it would also apply across Europe.
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aspinwing. Your example may well work in Canada and certain lumpier, sunnier parts of Europe but it certainly doesnt in the UK. +25 at 3000' and +31 at MSL? Might get that about two days a year if we're lucky. Most of the time we wont even be able to reach 3000' due to cloud cover!
Given that our climate is reasonably stable (= usually cr@p) then loading the heli up to a high gross weight is the only real variable we have to play with.
Given that our climate is reasonably stable (= usually cr@p) then loading the heli up to a high gross weight is the only real variable we have to play with.
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MaxNg,
Isn't a free turbine where N1 is the gas generator speed? In that case the generator speed (N2) could be less than the rotor rpm% (Nr) while the power turbine (N2) could be in mesh with (same % as) Nr. Put it this way--if there is no load on the power turbine and there are gasses still being pushed through it, then the power turbine would accelerate until a load (the MR) was applied (or until the turbine blades were at zero local angle of attack with the gasses) and N2 would be the same as Nr. Even in this case where N1 is much less than Nr, the power turbine may apply a small torque to the rotor system. So even if you're at flight idle, the Nr and N2 needles could be matched in theory, right? I think this is the difference between real EOLs and practice autorotations that was being discussed.
Edited for clarity.
[ 05 December 2001: Message edited by: Kyrilian ]
Isn't a free turbine where N1 is the gas generator speed? In that case the generator speed (N2) could be less than the rotor rpm% (Nr) while the power turbine (N2) could be in mesh with (same % as) Nr. Put it this way--if there is no load on the power turbine and there are gasses still being pushed through it, then the power turbine would accelerate until a load (the MR) was applied (or until the turbine blades were at zero local angle of attack with the gasses) and N2 would be the same as Nr. Even in this case where N1 is much less than Nr, the power turbine may apply a small torque to the rotor system. So even if you're at flight idle, the Nr and N2 needles could be matched in theory, right? I think this is the difference between real EOLs and practice autorotations that was being discussed.
Edited for clarity.
[ 05 December 2001: Message edited by: Kyrilian ]
Re the original question:
Everyone should be aware of the differences in autorotational characteristics at different ends of the weight spectrum.
The vast majority of practice autos we used to do in Hueys were at low to mid weights, but regularly we would load them up to max all up to do heavyweight autos. Fairly sporty at times - quite a difference, but the main things were:
1. You often had to carry some collective to keep the Nr under control.
2. The flare had to be started earlier and developed more and faster to slow you down and arrest the ROD.
3. There wasn't as much spare lever left at the end of the cushion-on.
All fairly obvious I guess, but a good thing to remind yourself of before going out with a full load.
Everyone should be aware of the differences in autorotational characteristics at different ends of the weight spectrum.
The vast majority of practice autos we used to do in Hueys were at low to mid weights, but regularly we would load them up to max all up to do heavyweight autos. Fairly sporty at times - quite a difference, but the main things were:
1. You often had to carry some collective to keep the Nr under control.
2. The flare had to be started earlier and developed more and faster to slow you down and arrest the ROD.
3. There wasn't as much spare lever left at the end of the cushion-on.
All fairly obvious I guess, but a good thing to remind yourself of before going out with a full load.
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Having been instructing twin engine helo's for years as well as flying them, the auto's I've practiced have shown that a/c wt not surprisingly has a major effect on rotor speed in auto as well as that developed during the flare. But the environmental conditions have as great an effect. 19,000lbs on a hot and high day makes for a rapid arrival flaring 250 - 300' but add 25 kts wind and your immediately better off as you've got much less ground speed to loose. At a lighter 16,000lbs and 30 kts (Not uncommon down here) I'd be leaving the flare to 100' or so. (A 60' rotor's got a lot of stopping power)
I'd consider it criminal not to practice auto's regularly as much as handling practice as to prepare for the event (Cross fingers). It will also give experience of different conditions/loads rather than just practicing occasionally in one configuration.
I'll never forget the couple of hours mutual practice engine off's in the Gaz on instructors course. Its amazing what you can avoid by bleeding the rotor speed down in the flare (Runways/runway lights/fences....they ought to sell tickets for it!!)
I'd consider it criminal not to practice auto's regularly as much as handling practice as to prepare for the event (Cross fingers). It will also give experience of different conditions/loads rather than just practicing occasionally in one configuration.
I'll never forget the couple of hours mutual practice engine off's in the Gaz on instructors course. Its amazing what you can avoid by bleeding the rotor speed down in the flare (Runways/runway lights/fences....they ought to sell tickets for it!!)
