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Training on grass

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Training on grass

Old 8th May 2021, 11:38
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Training on grass

I remember reading an article on the dangers of conducting autorotation training or run-on landings on grass. Iíve tried to search the archive along with the web browser and canít seem to find it. Anybody by chance know where it can be found.
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Old 8th May 2021, 12:26
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Autos onto grass are far more gentle on the skids. With wheels it doesn't matter as long as the grass is flat with no pot holes, same as for runways.
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Old 8th May 2021, 13:00
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It's not about being gentle with the carbides on the skids, it's about surviving training intact. Touchdown auto's are safer when done to pavement, it is far more forgiving of mistakes. On grass all it takes is a little left or right yaw on touchdown and an errant bit of turf to turn it into a rollover. But don't take my word for it, this question is easily researched on Google. Tim Tucker is as good an authority as you are likely to get, see his article here, scroll down to the Grass vs. Hard Surface discussion.
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Old 8th May 2021, 14:12
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Originally Posted by falcon920 View Post
I remember reading an article on the dangers of conducting autorotation training or run-on landings on grass. Iíve tried to search the archive along with the web browser and canít seem to find it. Anybody by chance know where it can be found.
Shawn Coyle did an article in 2005 on the very subject.
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Old 8th May 2021, 14:13
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I did all my training on grass, no problem. I don't agree that touchdown autos are necessarily always safer on pavement.
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Old 8th May 2021, 14:54
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Pavement doesn't have gopher holes
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Old 8th May 2021, 15:33
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"Training on grass" - I though this was going to be a whole different topic.......

Interesting article linked to above by the guy with lots of numbers in his name. I was actually very encouraged to see his advocacy for transmitting a 'Mayday' call ( not meant to provoke an "aviate, navigate, communicate" debate....) as this call seems to be something of an anathema to our US colleagues, in both big and small 'tin', who prefer to say they are "declaring an emergency" (typically when prompted by ATC). Pity he then went on to say the following:
Transmit ďmayday, mayday, maydayĒ over the radio (in some parts of the world itís ďpan, pan, pan")
a) "pan' and 'mayday' are different levels of severity of problem, and b) in the civil world it's "pan-pan, pan-pan, pan-pan". "pan, pan, pan" is, or certainly was, used by military crews - probably because in the FJ world there's better things to do with the time when things are going bad.
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Old 8th May 2021, 15:58
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Done both grass and pavement, both as student and instructor, everything from R22 to 412. Each has their risk, pavement is more uniform and predictable, but you have to ignore that horrible screeching noise. Lots of variables, as usual for the helicopter world, one size doesnít fit all. I like flat smooth hard grass cropped short.
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Old 8th May 2021, 16:32
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Originally Posted by 212man View Post
"Training on grass" - I though this was going to be a whole different topic.......

Interesting article linked to above by the guy with lots of numbers in his name. I was actually very encouraged to see his advocacy for transmitting a 'Mayday' call ( not meant to provoke an "aviate, navigate, communicate" debate....) as this call seems to be something of an anathema to our US colleagues, in both big and small 'tin', who prefer to say they are "declaring an emergency" (typically when prompted by ATC).
I'm not so sure that's true in the helicopter community in the US. I've heard two ATC audio recordings where the Mayday call was made. Both in the NYC area. One was back in 2013, a 206 engine out over the boat basin, popped floats and all was well. I can't seem to find that recording online at the moment. The other is the infamous shoe-selfie debacle, Youtube link posted below.

With the urgency associated with an auto from 1000ft AGL or less, I know I'm going to pop the M-word if I think of it and am talking to ATC at the time. But you are correct in that most fixed wing incidents do tend toward the "declaring an emergency" style of communicating. I also agree it is too bad, surprising even, that Tucker should confuse Mayday and Pan calls. As a mariner I've heard and made many Securite calls, heard many Pan calls, never heard an actual Mayday. As an aviator I have yet to hear my first live emergency, thank goodness!

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Old 8th May 2021, 18:01
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Originally Posted by aa777888 View Post
Touchdown auto's are safer when done to pavement, it is far more forgiving of mistakes. On grass all it takes is a little left or right yaw on touchdown and an errant bit of turf to turn it into a rollover.
What cobblers!
AFAIK no British service or civil helo training ever uses anything else but grass for touchdown auto's(sic). More advanced types with wheels are twins and don't do touchdown autos at all.

There is simply no concept in UK that grass is hazardous - it's all we use and it simply does not cause problems or else we wouldn't do it. The thought of doing an auto to a hard runway makes me cringe with horror at the thought of all that metal being ground away, even if they are sacrificial pads. Why do it???

In any case when you auto for real there ain't gonna be a nice concrete patch to land on so the ability to touch down straight and feather the aircraft onto the ground smoothly is an esential skill that you won't learn if all you learn is to plonk it on the concrete with drift on and dump the lever as you grind your way along half-sideways in a bonfire of expensive sparks...

However we are well aware that with t/r failures high speed run-ons are to be done on runways if at all possible. In a normal auto youalways have the ability (skill permitting...) to land straight if you choose to, in a t/r failure you likely do not.

It seems the objection to grass is a cultural rather than a realistic or practical concept.
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Old 8th May 2021, 18:03
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You can slide sideways-ish on tar. Doesnít work so well on grass.
Itís great if you can keep the pointy bits facing forward, if there is any lateral movement there is no substitute for smooth asphalt.
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Old 8th May 2021, 19:24
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Probably done over 5000 EOL's to grass with no problem what so ever so really no idea what you are talking about in being dangerous
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Old 8th May 2021, 21:21
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Well,
it all depends….
If you do autos to a well known gras area - you ˋll be fine most of the times.
Had to do a OEI landing and went for gras - as always trained until then - and dug in quite a bit, cause it was on a non familiar airfield…
Had to do another OEI landing and went for the taxiway close to the hangar instead of the runway, thinking about blocking the runway with the skid equipped helicopter and the tow distance
Well the taxiway was not only smal, it also had a slight slope, so the helicopter drifted towards the adjacent gras.
Remembered the role over of the police helicopter in Hannover, which drifted onto the gras and put the collective a little faster down then initially intended, creating a nice curved skid mark on the tarmac.
Two times moving from the luck bag into the experience bag - which I use much more often by now ;-)
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Old 8th May 2021, 22:07
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Hmm,...as a city and/or desert pilot I've always been meaning to ask,...

What's grass?
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Old 8th May 2021, 22:17
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agree with Hughes. Also done many hundreds of EOLs to both surfaces and never had a problem with either. I remember doing my FAA CFI to a grass surface with the FAA DPE watching from a distance, as they did in the old days.
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Old 9th May 2021, 00:54
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We were trained to do a 35 knot auto for IMC (Huey) with the hope you'd see the ground in time to pull pitch to arrest the descent and figuring running into something at that speed more than likely would be survivable. Used to practice them to touchdown on grass during the daytime, the only problem was maybe a bit of pylon rock on rough grass at low RPM.

Only ever did one auto to touchdown in a twin (76), instructor wouldn't put the throttles up in the flare if he thought things looked good, only once per pilot as a confidence builder, thought it mighty brave of him.
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Old 10th May 2021, 00:24
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From my side of things, I used to hate when it was time for the old AS350D recurrent training time with the D models below the nose mounted pitot tube and low skid gear. Seemed every week some anointed stick wiggler would either stick the tail skid in the mud or snag the nearest fire ant mound with the pitot tube during the full auto quals. Job security for sure but was happy when high gear and windshield level pitot arrived on the scene.
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Old 10th May 2021, 11:38
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We have got significant damage on a 206 during auto training on grass. When landed, the aft part of BOTH skids dipped in a sort of potholes, that were left behind by agricultural machinery-tractor, that dug two holes in a distance, exactly matching skids distance. (obviously made by tractor wheels that dug into softened soil during last rain) Potholes were perfectly hidden in grass. When collective was lowered, heli tilted backwards resulting in abrupt stick-forward reaction. A severe mast-bumping followed so mast, M/R Hub, XMSN mounts etc. had to be replaced. You never know what is hiding in the grass as long as it is not verified every time.
As a glider pilot, I was taught never to try out-of-airport landing on the grass, however temptating, if a plowed field is available too. This came with decades of experience. (and many damaged planes)
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Old 10th May 2021, 12:54
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well anyone who wants to do EOL's to a runway is welcome to show me how it is done at my home airfield here in UK EGTU. The runway built in 1943 is still there and used loads of times daily by our fixed wing brethren. By the way bring your own machine because you aint using any of mine
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Old 11th May 2021, 10:58
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I personally think the risk of EOL training to pavements (or airport grass even) is they are so forgiving, if the aircraft is not straight with forward speed at touchdown. This is obviously a good thing for initial training. But it is common to see on Youtube considerable run on speeds for EOL landings as the norm, and what is taught.

If you can't do a zero speed touchdown auto, without cutting the tail off, or have never been trained to do so, then you will almost certainly roll it over on an unprepared surface for real, with bad results for survivability. Try running it onto a beach, or the water, or the forest. Helicopters are built to survive significant vertical impacts but not being rolled over, even at slow speed.

Training is only helpful if it can be put into successful practice if the time comes, and such safe forgiving landing environments are rarely available. Think about the most common environment you fly over day in day out and make sure you are trained to survive landing in that if need be.
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