Water Ditching
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Water Ditching
Opinions please on the best (better/safer) options in which direction to rolling over a helicopter after an emergency water auto landing please? I have been told roll her over to the right in an anti-clockwise machine so that the reaction from the blades impacting the water sends the tranny & engine backwards away from you. Others have said attempt to settle her in flat so all blades contact water at the same time? Thoughts, comments, experience on this topic gratefully appreciated. Cheers
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I dunno but methinks that once you hit the water you're along for the ride. The helicopter is likely going to roll one way or another; just roll with it. Resistance is futile... What are you doing over water without floats anyway?
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Rolling in any direction is an old wive's tale, discredited by the flight manuals and military procedures for several years now, but awfully hard to wipe from public memory.
If you have to ditch, open the doors prior to touchdown if you can, enter the water nicely, and let the aircraft settle straight down, holding it upright with cyclic as long as you can.
The greatest danger in ditching is drowning, and doing a roll at entry is a fine way to invert the aircraft, get lost trying to find the exit and drowning.
If you have to ditch, open the doors prior to touchdown if you can, enter the water nicely, and let the aircraft settle straight down, holding it upright with cyclic as long as you can.
The greatest danger in ditching is drowning, and doing a roll at entry is a fine way to invert the aircraft, get lost trying to find the exit and drowning.
Ditching..
We were always taught that if it was a controlled ditching, to try and land on the crest of any waves (if there was a significant sea state) and NOT to use the rotor brake while shutting down 
Oh yeh, and keep yer head down till the blades have stopped
Oh yeh, and keep yer head down till the blades have stopped
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I agree with Nick.
Planning ahead is the most important safety consideration (training, utility or emergency floats, personal flotation devices, and a plan).
Part of the emergency plan should be to open a door or window during the descent so that an expeditious exit can be performed.
As anyone who has experienced a dunk tank will attest, exiting the aircraft while upright is far less difficult than when it has rolled past the vertical to the inverted.
Planning ahead is the most important safety consideration (training, utility or emergency floats, personal flotation devices, and a plan).
Part of the emergency plan should be to open a door or window during the descent so that an expeditious exit can be performed.
As anyone who has experienced a dunk tank will attest, exiting the aircraft while upright is far less difficult than when it has rolled past the vertical to the inverted.
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"Rolling in any direction is an old wive's tale, discredited by the flight manuals and military procedures for several years now, but awfully hard to wipe from public memory."
The Army still teaches rolling right to stack the broken blades over the tail and thus not impede exiting from the cabin. At HUET they preached rolling and not riding it straight down, as the helicopter will roll eventually and better to get it rolling and done while still early in the crash sequence -- the dunker machine is set up to roll immediately when it contacts the water to teach such a little event.
Plus the Robby POH says roll left, no clue why left but it says roll.
Personally, I don't care what kind of top gun maneuver the pilot pulls after hitting the water, and I doubt it makes too much of a difference what he does, but it still is actively being preached! I still believe that doing a good auto to 20 feet and pulling the crud out of the collective while leaping from the cockpit is the most appealing option in my eyes... no need to escape a twisted wreck; it's just like doing a dive off the high jump with a fat kid rolling in with a cannonball on top of you.
Mike
The Army still teaches rolling right to stack the broken blades over the tail and thus not impede exiting from the cabin. At HUET they preached rolling and not riding it straight down, as the helicopter will roll eventually and better to get it rolling and done while still early in the crash sequence -- the dunker machine is set up to roll immediately when it contacts the water to teach such a little event.
Plus the Robby POH says roll left, no clue why left but it says roll.
Personally, I don't care what kind of top gun maneuver the pilot pulls after hitting the water, and I doubt it makes too much of a difference what he does, but it still is actively being preached! I still believe that doing a good auto to 20 feet and pulling the crud out of the collective while leaping from the cockpit is the most appealing option in my eyes... no need to escape a twisted wreck; it's just like doing a dive off the high jump with a fat kid rolling in with a cannonball on top of you.
Mike
If you have done an auto to the water in a single, you probably won't have enough Nr left to give you much cyclic control and since most helicopters are top-heavy, they will invert as they sink regardless of which way you try to put them in. Know your escape exit and get one hand on there as soon after impact as possible to help orientate yourself for the escape.
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Back in the olden days... we were taught if you had a controlled ditch, get everybody else out in the hover and then the expensive nut holding the cyclic would head downwind/current and put the thing in the water, pull throttles or twist the twist grip or shut off the main steam valve or whatever your particular machine required.
Jumping out from an auto at 20'? Sounds like something the Pink Panther (cartoon) would do. Just before the plane smacks the ground... jump up! I mean, it can't hurt to try, right? That sounds like an excellent way to die to me. A 20' uncontrolled fall into water WILL hurt... and a few thousand pounds of alloy and composite whirling in on top of one will hurt a bit more.
Rolling over? If one has floats... maybe it WON'T roll over (immediately, I mean). In that case, why make it worse by deliberately rolling it? Also, what if it's one of those Grenouille machines... then all that rolling right jazz doesn't work, anyway.
I can't speak for anyone else's skills, but I'm dubious of my own ability to will a helicopter to remain stable with decaying RRPM at 20' while I unstrap, swing myself around the various levers and so on to make good my escape (don't forget to unplug the helmet/headset!). Best place to be during rotor blade impact is generally under the hub, more or less... all the bits fly away from one, at least that's what the books sort of say... never tried it myself, you understand.
Take HUET seriously... don't whine when you get water in your sinuses during training...
Nothing personal... but my observations have been that what US Army Aviation as an official organization knows about flying over and around water wouldn't fill a thimble (there are plenty of individuals who are exceptions to that). Used to escort a bunch of Army folks inter-island because they wouldn't fly over open ocean on their own... like herding along little olive-colored ducklings t'was... (kept their t*sticles in a little mason jar with a flotation collar for 'em... safekeeping you understand... returned them to 'em when they got to Bradshaw)
Jumping out from an auto at 20'? Sounds like something the Pink Panther (cartoon) would do. Just before the plane smacks the ground... jump up! I mean, it can't hurt to try, right? That sounds like an excellent way to die to me. A 20' uncontrolled fall into water WILL hurt... and a few thousand pounds of alloy and composite whirling in on top of one will hurt a bit more.
Rolling over? If one has floats... maybe it WON'T roll over (immediately, I mean). In that case, why make it worse by deliberately rolling it? Also, what if it's one of those Grenouille machines... then all that rolling right jazz doesn't work, anyway.
I can't speak for anyone else's skills, but I'm dubious of my own ability to will a helicopter to remain stable with decaying RRPM at 20' while I unstrap, swing myself around the various levers and so on to make good my escape (don't forget to unplug the helmet/headset!). Best place to be during rotor blade impact is generally under the hub, more or less... all the bits fly away from one, at least that's what the books sort of say... never tried it myself, you understand.
Take HUET seriously... don't whine when you get water in your sinuses during training...
Nothing personal... but my observations have been that what US Army Aviation as an official organization knows about flying over and around water wouldn't fill a thimble (there are plenty of individuals who are exceptions to that). Used to escort a bunch of Army folks inter-island because they wouldn't fly over open ocean on their own... like herding along little olive-colored ducklings t'was... (kept their t*sticles in a little mason jar with a flotation collar for 'em... safekeeping you understand... returned them to 'em when they got to Bradshaw)
Last edited by Um... lifting...; 21st May 2008 at 10:53.
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"(kept their t*sticles in a little mason jar with a flotation collar for 'em... safekeeping you understand... returned them to 'em when they got to Bradshaw)"
Funny you say that... current policy out in Hawaii is no single ship VFR interisland flight. IFR for single aircraft only. Ridiculous. Had a chopper have an gyro break on the way to Maui, they launched two ships VFR to escort the one chopper back on a clear blue day.
The singles (58s) have a harder time... nothing allowed to the other islands unless you are going to Bradshaw for a field exercise. Risk aversion at its finest.
Funny you say that... current policy out in Hawaii is no single ship VFR interisland flight. IFR for single aircraft only. Ridiculous. Had a chopper have an gyro break on the way to Maui, they launched two ships VFR to escort the one chopper back on a clear blue day.
The singles (58s) have a harder time... nothing allowed to the other islands unless you are going to Bradshaw for a field exercise. Risk aversion at its finest.
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Funny you say that... current policy out in Hawaii is no single ship VFR interisland flight. IFR for single aircraft only. Ridiculous. Had a chopper have an gyro break on the way to Maui, they launched two ships VFR to escort the one chopper back on a clear blue day.
Like I say... put Army Aviation decision-makers over water, watch their brains dissolve... it's a phenomenon that has been observed independently by many people of my acquaintance. They are like Southern drivers in snow flurries... they just lose their minds.
So, could they have launched one IFR to get the broken one and then they could return VFR? Or was the gyro-free one not considered to be in flyable condition?
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I have been told roll her over to the right in an anti-clockwise machine so that the reaction from the blades impacting the water sends the tranny & engine backwards away from you.
I have seen a machine where a M/R strike on the retreating blade (ground strike) put a dent in the pilots head from the xmon severe enough to put him out of flying forever. (the pilot had a helmet on, but to no avail)
I am surprised at Nick's statement.
In Mechanics every action has an equal and opposite reaction.
When hitting the ground , or the water, think;
1. Do you have lots of energy on the M/R system? How can I use that to my advantage, (if it is necessary) especially to dissipate damaging velocity?
2 Answer. After disspating the downward velocity, (only if into water) then roll the advancing blade into the oncoming obstacle.
3. The items which it is connected to, I.E. the xmon must tear backward away from the cabin occupants. Have seen that many times.
Above all, THINK. Energy is stored in the rotor sytem while it is rotating.
Think about how you can use it to help yourself.
Water strikes tear airframes apart like you wouldn't believe.
Tearing of airframes is better to be used for time (and energy disspation) to get out from under water.
tet
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Hawaii: Don't want to hijack the thread, but...
I never knew that about Hawaii. I used to fly off the chart in the GOM in a medium, and about 150 miles off the beach VFR in a 206L (3 years ago).
Why would they place such an odd restriction on inter-island flights?
Why would they place such an odd restriction on inter-island flights?
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Roll it away from your side so you put the other pilot under water!!
Seriously there was a lot of vision years ago of Vietnamese pilots fleeing Saigon to US warships at sea. These "controlled" ditchings by pilots with questionable skills showed that the water entry was relatively benign and survivable. A night "autorotative" entry from "jump" height possibly downwind is altogether a different story. I have friends who have done this and most would say they put in control inputs almost by numbers on the gauges and found themselves on the surface. The RAN had lost no-one in a ditching from 1948 until around the 1980's when two backseat crew died as a result of an upside down uncontrolled ditching from around 40-50 feet at 30kias or so when a main rotor gearbox gear exploded and took out one of the Wessex's primary jacks.
Take HUET seriously, know your primary/secondary escape routes and always consider the possibility of a controlled/uncontrolled diching - have a plan.
GAGS
E86
Seriously there was a lot of vision years ago of Vietnamese pilots fleeing Saigon to US warships at sea. These "controlled" ditchings by pilots with questionable skills showed that the water entry was relatively benign and survivable. A night "autorotative" entry from "jump" height possibly downwind is altogether a different story. I have friends who have done this and most would say they put in control inputs almost by numbers on the gauges and found themselves on the surface. The RAN had lost no-one in a ditching from 1948 until around the 1980's when two backseat crew died as a result of an upside down uncontrolled ditching from around 40-50 feet at 30kias or so when a main rotor gearbox gear exploded and took out one of the Wessex's primary jacks.
Take HUET seriously, know your primary/secondary escape routes and always consider the possibility of a controlled/uncontrolled diching - have a plan.
GAGS
E86
Last edited by eagle 86; 22nd May 2008 at 06:04.
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Topend, you are correct ref the advancing blades striking the water (Or anything) will tend to push the transmission back. 2, 3. 4 5 or whatever the amount of blades will not matter.
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"Never mind that you can go FSS and tower-to-tower pretty much all through the Hawaiian chain, or at least it used to be you could."
It's still used for multi-ship VFR flights. But regardless, HCF does great VFR flight following across the whole chain. Seamless. Nobody uses IRS anymore except military chums. And the logic was that if you were alone and had a problem, being IFR would make the rescue come much quicker
I fly inter-island in the pistons outside of work and all the coworkers think I'm absolutely nuts.
Anyone who does even a bit of overwater flight should do HUET. One of the most eye-opening experiences I've ever done. Also, the HEEDS bottle is the best thing since franks and beans... even in training, having that puppy on you reduces the fear and stress of going in 10 fold. You can buy a small "spare air" tank that Scuba divers carry for a hundred dollars and never worry again about getting snagged and running out of air, or having to leave an unconcious/trapped person in the sinking wreck because you need to surface to breathe.
Mike
It's still used for multi-ship VFR flights. But regardless, HCF does great VFR flight following across the whole chain. Seamless. Nobody uses IRS anymore except military chums. And the logic was that if you were alone and had a problem, being IFR would make the rescue come much quicker
I fly inter-island in the pistons outside of work and all the coworkers think I'm absolutely nuts.
Anyone who does even a bit of overwater flight should do HUET. One of the most eye-opening experiences I've ever done. Also, the HEEDS bottle is the best thing since franks and beans... even in training, having that puppy on you reduces the fear and stress of going in 10 fold. You can buy a small "spare air" tank that Scuba divers carry for a hundred dollars and never worry again about getting snagged and running out of air, or having to leave an unconcious/trapped person in the sinking wreck because you need to surface to breathe.
Mike
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Also, the HEEDS bottle is the best thing since franks and beans... even in training, having that puppy on you reduces the fear and stress of going in 10 fold. You can buy a small "spare air" tank that Scuba divers carry for a hundred dollars and never worry again about getting snagged and running out of air, or having to leave an unconcious/trapped person in the sinking wreck because you need to surface to breathe.
The SOLE purpose of HEEDS is to assist yourself to escape from a ditched machine. Having it with you significantly increases your chance of survival should you be or become snagged during your initial attempt to escape but to state that you never worry again about running out of air is wrong. There is no question that in such an unfortunate event the shock and possibly also cold shock effects will cause you to hyper-ventilate and that little bottle of air wiill not last long.
Not to mention a number of other gotchas that will catch someone out using such equipment without training.
However more importantly it should never be viewed as a means of assisting an unconscious or trapped person in a sinking wreck. Yes of course we would all like to be considered hereos who will save the day and all the passengers with our acts of selfless bravery but going back into a sinking aircraft with a small spare air supply will undoubtedly add an extra name to the casualty list - yours
