Scenario - What would YOU do?
Ok, serious question, as this happened to me and I'm trying to learn from the experience:
R22, instructor + student. Climbing out, on right x-wind, 6-700', over water All drive to rotor system lost Autorotation only option Left turn gives you into-wind auto but into deep water Right turn takes you very close to shore, shallow water (10') but downwind auto Wind speed approx. 10kts Which option do you take and why? Thoughtful answers would be appreciated. Thanks |
Never flown R22 so not sure how much a downwind eol would be affected. BUT, close to shore works for me every time.....
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I'd take the shoreline myself. Deep water is not my thing...
RH |
to the right, towards the shallow water.
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Looks like someone chose 'the into wind and wet' option on this one and got away with it. Personally I prefer to be on terra firma with a wreck than a perfect auto into the ocean.
http://www.youtube.com/watch?v=gXMLCZJI-Xc At the end of the day, it's the Captains decision F. ___________________ Free Beer - Tomorrow! |
I would reckon a better question would be...."Why get over water to the extent you cannot make it to the sandy beach if the Donk dies?".
Please recall that if you jump into a well...the Good Lord ain't bound to fetch you out!:= |
Knowing the R22 well, I'd carry on into wind, if the water is 10 feet or 100 feet deep it doesn’t matter - you are still swimming. Do you want to hit the water at speed (10 knots plus 30-40 at the bottom of the auto) or not (30 -40 minus 10 knots)?
I think that realistically by the time you reestablish RRPM (climbing out remember) and get things settled down, you are probably better off concentrating on getting to the water in one piece. At least if you can enter the water without smashing things up you will be able to swim away. I would assume lifejackets are worn over the water and that you are at an airfield? A mayday call would be quickly responded to. However without a lifejacket I would be keen to reduce the swimming distance, but not at the risk of hitting the water at high speed. :hmm: |
And if you can judge a flare height over open water with no immediately available reference(the shore), good on ya. But with 10kts on the tail, the shoreline is where I'd go. However, SASless makes a good point, turn before going out over the water....
RH |
SASless - I agree, but in this case there is no option. The airfield is on the waters edge and the circuit takes you over water.
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You have 700 feet which would assume you probably have reasonable airspeed. Can you do a 270 degree auto and have your cake and eat it to? If not, given the height and airspeed, head for the beach and manage the kinetic energy knowing you have a downwind flare.
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Originally Posted by Wildwilly
SASless - I agree, but in this case there is no option. The airfield is on the waters edge and the circuit takes you over water.
Failing that, dietlhelm's 270 auto would be my preference. From 700 feet you should have enough height to do that. We used to do 360 autos from 1000 feet in the Bell 47. |
I am not convinced that a 270 auto would work. Firstly the RRPM have to be recovered, then the height loss in the turn and any inbalance would add to the rate of descent.
I would stay on the x wind heading and accept the fact that I would have to flare across wind, but would be closer to the shore. It does depend on the wind speed though. If the wind is strong then a slight turn towards the wind would give a better landing and the distance out would not have increased very much. In light winds it would be best to make it towards the shore. Here is a thought...If you were autorotating downwind, you flare, and just as you were levelling for touchdown applied full pedal so that the landing on the water was in a backwards movement. Would this not, give you the best chance of survival? |
Many factors
Many factors needs to be considered:
Water temperature Swimming skills and physical condition of the occupants Survival equipment and training SAR assets in the area etc These factors can be used to determine the risk of not reaching the shore following a successful ditching. This risk must be evaluated against the increased risk of performing a ditching with slighty higher airspeed nearer land. I'm not familiar with the helicopter type, but normally is is possible to perform a (slight) turn into wind during the flare. A somewhat higher ROD is no crisis as water is substantially softer than the ground (at the impact speeds we are discussing). |
Alternative thoughts.....
Originally Posted by Head Turner
I am not convinced that a 270 auto would work. Firstly the RRPM have to be recovered, then the height loss in the turn and any inbalance would add to the rate of descent.
An alternative idea, again depending on the wind strength. Would it not be possible to perform a constant attitude auto or, better still, a zero speed auto - ie zero ground speed. In a reasonably strong wind you could even achieve a rearwards ground speed for the first part of the exercise!! This should minimise the distance travelled out to "sea". |
Flying single-engine over water out of auto range of the shore without flot gear is criminal - full stop!
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Originally Posted by oldbeefer
Flying single-engine over water out of auto range of the shore without flot gear is criminal - full stop!
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Perhaps the question should not be "what would you do?" rather "what should you be teaching your student to do?", as this seems to be a training environment we're discussing here.
As posted before - 10 feet of water will still drown you and wreck the aircraft. How many low time students can be relied upon to succesfuly identify an engine failure then enter autorotation, initiate a 180 deg turn, maintain airspeed whilst turning downwind then flare and cushion with a ten kt tailwind? If it's an over water circuit then they should be wearing Life-jackets and the student should be briefed thoroughly on water escape, door jettison etc. That done i would have thought that yelling for help (use the radio if it helps!), holding your course into wind and carrying out a normal into wind flare is going to be the most survivable thing to teach a low time student. If it's a licenced airfield that close to water then chances are it has a rescue boat. If you get out ok (more likley after an into wind ditching i think) and if you are still floating (Lifejackets!!!) then you should be picked up pretty promptly whether you are ten yards off the beach or half a mile out. If there is no rescue facility then you have to be asking should i be training students here? Safe flying (and dry landings!) |
So what did you do Wildwilly?
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I would bend forward, put my head between my legs and kiss my arse goodbye.
SB |
So thanks to everyone who has posted replies so far.
As Farm Pilot has asked the obvious question I'll try to explain what I did and my thought process. I'm willing to accept that I may have made the incorrect decision if popular opinion disagrees with my actions. As I said in my original post, I'm trying to learn from this and hope that maybe this discussion will help someone else one day... As Teefor Gage said, not putting yourself in the situation is not an option. Both ends of the airport head out into the ocean and there are houses all around. A bit of a buggar but that's what we have to deal with. My option was to head for land, even though I knew I wouldn't quite make it and accept the downwind auto, given that the wind speed was no greater than 10kts. As we were already 90 degrees to the runway (x-wind remember) it only required a further 90 degree turn. Just so you understand, this was a double vee-belt failure for reasons currently unknown and no warning light to indicate impending failure. I would never normally suggest that anyone should ever do an auto any way except into wind. However, in saying that what follows was the sequence of events plus my thoughts and actions as things happened: Loud thud from engine bay area - ****, what was that? :confused: Immediate left yaw, rotor rpm decay and engine overspeed - Holy crap :uhoh: Enter autorotation :mad: Immediate assessment of where we were Any boats nearby? No - buggar :sad: Into-wind auto into deep water or keep going right, towards shore? - Won't quite make it but shallow water and only a light tail wind. Emergency radio call stating intentions Manipulated throttle to see if any drive left at all - Nope, none, buggar again Keep RRPM low'ish (90-95%) and extend glide as far as possible before flare Instruction to student to open door before impact Flare, flare, flare, holding until airspeed gone and groundspeed minimal Deliberately let tail touch water first then levelled and raised collective simultaneously with gentle water contact Helicopter immediately filled with water, rolled uncontrollably to the right, rotors hit and stopped, student exited and I climbed up over the now jammed collective as the helicopter sank. Time from impact to completely submerged - approx 5-10 seconds. Now, as far as I was concerned, having undergone Helicopter Underwater Evacuation Training and understanding how quickly a helicopter sinks and how easy it is to panic and get disoriented, as soon as the emergency was in progress my student stopped being a student and became a passenger who's life might depend upon my actions as PIC I decided on the shallow water option because most people who die in a ditching do so as a result of drowning - not from the impact. Ok, you can be equally successful at drowning in 10' of water as you can be in 60' but I didn't want to be trying to dive down 60' to the wreckage to try and extricate my 'passenger' if for whatever reason they hadn't managed to get out. So, any other comments anyone would like to make? Suggestions? By all means be critical but please be constructive at the same time. Thanks! |
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