Bristow Academy 206 down, Florida
Joined: Jul 2001
Posts: 420
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From: Florida
I've done hundreds of touchdown autos at night, both with NVG's and without. The only time I've seen sparks was when we lost a skid shoe and the the skid tube snapped. That was impressive.
With regards to full downs being unnecessary I couldn't disagree more. The main problem that I have seen doing power recoveries is that people terminate too early. People trained to do that, unfortunately in the real event, will do what they have been trained to do. There is no use being trained to terminate an auto at 20 feet agl.
We had a technique on power recoveries where we would bring the throttle in prior to the flare. Once the flare is complete and collective is being brought in to cushion, the throttle is rolled off to terminate with a hovering auto. This works great, but be warned if you or the instructor are not very proficient at it don't try it as you can end up in a spectacular over torque.
The most important thing in a Jet Ranger at the end of an auto is GET IT LEVEL!!! You can drop a Jet Ranger from a frightening height and as long as she hits the ground level you can get away with no damage. Seen it and done it. Either that or my guardian angel was working overtime!
One last point. From an instructors point of view every autorotation should be treated as though the engine will fail and a power recovery is not an option. Then if it does fail you are not caught by surprise and are already mentally prepared to take it to the ground. Be careful where you roll that throttle off.
With regards to full downs being unnecessary I couldn't disagree more. The main problem that I have seen doing power recoveries is that people terminate too early. People trained to do that, unfortunately in the real event, will do what they have been trained to do. There is no use being trained to terminate an auto at 20 feet agl.
We had a technique on power recoveries where we would bring the throttle in prior to the flare. Once the flare is complete and collective is being brought in to cushion, the throttle is rolled off to terminate with a hovering auto. This works great, but be warned if you or the instructor are not very proficient at it don't try it as you can end up in a spectacular over torque.
The most important thing in a Jet Ranger at the end of an auto is GET IT LEVEL!!! You can drop a Jet Ranger from a frightening height and as long as she hits the ground level you can get away with no damage. Seen it and done it. Either that or my guardian angel was working overtime!
One last point. From an instructors point of view every autorotation should be treated as though the engine will fail and a power recovery is not an option. Then if it does fail you are not caught by surprise and are already mentally prepared to take it to the ground. Be careful where you roll that throttle off.
Joined: Jul 2007
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From: UK, US, now more ɐıןɐɹʇsn∀
Yeah, those 206 autos are way easier than R22. Even the R44 rotor inertia is way better than little Robbie. What a luxury, having that much time and inertia being couple inches off the ground for so long to get it right.. The only issue for power recovery could be the spool up time in turbines, but I'm too rookie to know turbines personally.
Savoia, the article Shawn wrote should be in one of the Vertical magazine issues.
Agree with vaqueroaero. As my high time CFI course instructor/'old timer' reminded, regarding doing off-airports autos, that the power recovery may not happen and therefore suitable place to set it as if for real, is important.
Night full downs? Hm. I wish I was that good to be comfortable with them in future. But I'm not military, so I guess I'd not get to do that.
Savoia, the article Shawn wrote should be in one of the Vertical magazine issues.
Agree with vaqueroaero. As my high time CFI course instructor/'old timer' reminded, regarding doing off-airports autos, that the power recovery may not happen and therefore suitable place to set it as if for real, is important.
Night full downs? Hm. I wish I was that good to be comfortable with them in future. But I'm not military, so I guess I'd not get to do that.
Joined: Jan 2005
Posts: 1,529
Likes: 2
From: yorkshire uk
Just a couple of points ...
1) I am not against EOL ,s in principle but think that follow through demos from the instructors is enough .
2) When i did my training in the States we never did them to the ground because a) the owners didnt want it and b) the students didnt want to take any risk of damaging a ship and delaying their training !!
3) Power recovery at a height of between 4 and 8ft should ensure that you get out in one piece . I know of many many machines written off or badly damaged practicing but only know of one or two saved in a real failure . I can also say that when i had a total failure i landed it fine AND had only done power recoveries . This shows that if you do the recovery at the end of a flare which brings you to the correct height and speed you actually have very little else to do !!
Just pull collective and keep cyclic centred and thats it .
Lastly i would accept that my views as an owner will be different to a lot of you guys who just fly and dont pay the bills ...or the premiums ..
1) I am not against EOL ,s in principle but think that follow through demos from the instructors is enough .
2) When i did my training in the States we never did them to the ground because a) the owners didnt want it and b) the students didnt want to take any risk of damaging a ship and delaying their training !!
3) Power recovery at a height of between 4 and 8ft should ensure that you get out in one piece . I know of many many machines written off or badly damaged practicing but only know of one or two saved in a real failure . I can also say that when i had a total failure i landed it fine AND had only done power recoveries . This shows that if you do the recovery at the end of a flare which brings you to the correct height and speed you actually have very little else to do !!
Just pull collective and keep cyclic centred and thats it .
Lastly i would accept that my views as an owner will be different to a lot of you guys who just fly and dont pay the bills ...or the premiums ..
Joined: Jun 2005
Posts: 126
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From: South Florida
Nigel,
Unfortunately I dissagree - EOL's are required by the Licence Issuing Authority here for all instructor training.
Additionally I strongly belive that any CPLH student should have the confidence in the machine and the ability to be able to put the machine on the ground in the event of an emergency (especially if they are going to be using the shiny new CPL H they have earned).
We routinely teach EOL's to the ground in the R22/R44/S300 machines but ALLWAYS to a hard paved surface and unfortunately its a training risk we have to accept as an operator in order to deliver our product.
Hope you are well and its sunny in 'ULL - should be over in the next month or so for a quick visit.
Geoff
Unfortunately I dissagree - EOL's are required by the Licence Issuing Authority here for all instructor training.
Additionally I strongly belive that any CPLH student should have the confidence in the machine and the ability to be able to put the machine on the ground in the event of an emergency (especially if they are going to be using the shiny new CPL H they have earned).
We routinely teach EOL's to the ground in the R22/R44/S300 machines but ALLWAYS to a hard paved surface and unfortunately its a training risk we have to accept as an operator in order to deliver our product.
Hope you are well and its sunny in 'ULL - should be over in the next month or so for a quick visit.
Geoff
Joined: Jan 2005
Posts: 1,529
Likes: 2
From: yorkshire uk
Well if those are the requirements then I accept they need to be done .... I just wish people wouldn't mess so many up with the resulting higher premiums !!!!
Hope all well in sunny Florida ....thinking of coming over to do IR .....seems a waste flying around in 109 vfr !!!! N
Hope all well in sunny Florida ....thinking of coming over to do IR .....seems a waste flying around in 109 vfr !!!! N
Joined: Jan 2005
Posts: 90
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From: Always on the back of the drag curve.
In the Bristow of old we never carried out touchdown autorotations on high skid gear equipped B206's (AB206's). We never carried them out to a paved surface although I do remember doing them out in the desert in Dubai on hard sand.
We would swap skids to train - not negotiable. Maybe they had learned from hard experience.
With the low skid gear the rotor mast is vertical when the skids are parallel with the ground, so if you are at almost zero ground speed at the correct height - all should be well.
If you have a slightly higher forward speed at touchdown then the lower CofG helps to save the day. Maybe the Academy should look to the past - easy to say that now, of course! UG
We would swap skids to train - not negotiable. Maybe they had learned from hard experience.
With the low skid gear the rotor mast is vertical when the skids are parallel with the ground, so if you are at almost zero ground speed at the correct height - all should be well.
If you have a slightly higher forward speed at touchdown then the lower CofG helps to save the day. Maybe the Academy should look to the past - easy to say that now, of course! UG
Joined: Dec 2001
Posts: 1,835
Likes: 3
From: Philadelphia PA
High skid gear - hadn't thought of that for the upcoming book (Little Book of Autorotations), but will definitely include it.
Once again, pprune's rotorheads come through with great feedback and ideas.
Keep it up!
Once again, pprune's rotorheads come through with great feedback and ideas.
Keep it up!
Joined: Jan 2001
Posts: 3,009
Likes: 62
From: North Queensland, Australia
In the Aussie military system while I was involved (not recently, only up to about '95) our touchdown autos - and there were lots of them - were done almost exclusively to grass.
You would always check it out first so you didn't use anything too spongy, and it was very kind on the skids and pretty straightforward. Firm, dry, shortish grass is good.
I heard of a few problems where guys ended up rocking forward on the toes when the skids dug in on softer grass, but in general it worked very well.
This was Hueys and Squirrels, and I know the Kiowa guys did it too.
You would always check it out first so you didn't use anything too spongy, and it was very kind on the skids and pretty straightforward. Firm, dry, shortish grass is good.
I heard of a few problems where guys ended up rocking forward on the toes when the skids dug in on softer grass, but in general it worked very well.
This was Hueys and Squirrels, and I know the Kiowa guys did it too.
Joined: Dec 2005
Posts: 19
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From: Earth
Interesting discussion about an accident that may not even have been a result of an autorotation - anybody have the facts? ...and I hear that BA are flying more like 35,000 hours a year ...and five accidents in the last 2 year's seems excessive - maybe more like 2 or 3 with no injuries so the accident rate as set against the industry standard of accidents per 100,000 flight hours is pretty low compared to the US or worldwide training accident rate.
Joined: Sep 2003
Posts: 2,081
Likes: 189
From: Redding CA, or on a fire somewhere
autoranger...
Welcome back.....I wonder who you work for....
I do agree with you though:
All in the interest of learning and education....which is what Bristow is all about right.....? Even I was forced to think and learn about something on the interesting thread----how high skid gear and vertical CG can affect your stability in the touch down phase of an auto.
Tis all good.
Welcome back.....I wonder who you work for....
I do agree with you though:
Interesting discussion
Tis all good.
Joined: Jan 2005
Posts: 90
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From: Always on the back of the drag curve.
Looks like the autorotation to the ground "conspiracy theory" was duff. Nevertheless, it was all good stuff.
Could we have the dynamic rollover protagonists come forward please. Not my forte. UG
Could we have the dynamic rollover protagonists come forward please. Not my forte. UG
Joined: Apr 2007
Posts: 645
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From: Center of the Universe
hadn't thought of that for the upcoming book (Little Book of Autorotations),
It is my understanding (possibly wrong) that the practice lanes at BTA are paved with a "fine grained" asphalt that further reduces friction and the possibility of hooking a skid. IMHO, it is quite important to know what the nature of the surface is to which you are doing practice (touchdown) autos. Not all asphalt is created equal. Grooved runways at larger airports can ruin your day especially if you get a little yaw cranked in. Have been advised to use the (ungrooved) taxiways for this kind of thing, including run on landings and any other maneuvers where the helo may slide across the surface yawed from the direction of travel either as a result of poor technique or an emergency that doesnt readily permit a choice (possibly a hydraulics failure or tail rotor emergency).
Last edited by EN48; 10th March 2012 at 19:50.
Joined: Jul 2001
Posts: 420
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From: Florida
EN48 - you are correct. The Bell practice area is a fine grain asphalt, made smoother by the fact that there have countless thousands of autos done to them which has in effect made even smoother. When I had my mishap with the skid shoe coming off it was on the grooved concrete taxiway at Alliance, which we were using because the practice area was iced over.
Joined: Jul 2007
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From: UK, US, now more ɐıןɐɹʇsn∀
Anything with overhead throttles!
Joined: May 2008
Posts: 330
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From: St Johns, Newfoundland,Canada
MartinCH,
Fuel control is on floor next to collective on Astar, unless you have twist grip option. Fleet I fly don't, so yep training pilot controls throttle....it's all good,just make sure ya don't pull throttle back too far....whoops if you do....
no idle stop. As for main rotor rotation on EC, after a while makes no diference. Our fleet consists Astar B2's BA, Bell Longrangers and 205, we often hop between a/c, don't have to think about the difference the blades are turning.....
Fuel control is on floor next to collective on Astar, unless you have twist grip option. Fleet I fly don't, so yep training pilot controls throttle....it's all good,just make sure ya don't pull throttle back too far....whoops if you do....
no idle stop. As for main rotor rotation on EC, after a while makes no diference. Our fleet consists Astar B2's BA, Bell Longrangers and 205, we often hop between a/c, don't have to think about the difference the blades are turning.....
Joined: Jul 2007
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From: UK, US, now more ɐıןɐɹʇsn∀
Thanks.
My bad. I remembered reading about helicopters that do not have standard twist grip throttle. AS350 and S76 were mentioned. Hence mistaking it or remembering the overhead quadrant.
My bad. I remembered reading about helicopters that do not have standard twist grip throttle. AS350 and S76 were mentioned. Hence mistaking it or remembering the overhead quadrant.
