Russian Water Landing & Sinking [Archive]

Ascend Charlie

17th Jan 2009, 08:58

This thread was around a couple of years ago. First scene, helo has single engine failure, blades cone up, sinks onto water.
To stabilise the aircraft, he lowers the gear to keep the cg low.

Some time later, he attempts a single-engine takeoff, but has forgotten to raise the gear, so the drag tips him over. Should have stopped when his window went under the first time, but the scene continues and over he goes.:sad:

Lt.Fubar

17th Jan 2009, 10:42

Here on Mi-14s the crew chief (flight engineer) is the one to prevent pilots from doing stupid things. I know of one occasion when a pilot submerged whole nose on take of and tried do get out of the situation by applying more collective (not a good thing) - crew chef stepped into action reducing power on both engines allowing the machine to float up, and avoiding main rotor blades from striking the water.

The whole idea of amphibious helicopter is not very good - it was prised by USCG in the days of Pelican, but on Mi-14 it just make it dissolve faster, as the water landings are part of routine training, even though I don't remember if in the last 25 years they had to do this operationally. Kind think of it, the same goes for the life rafts inside - there are 5-6 oil-drum-sized rafts stored, and they were last time used during Hevelius sinking in 14th January 1993 (didn't do anything good, but that's a different story).

206Fan

17th Jan 2009, 13:16

Ascend Charlie

First scene, helo has single engine failure, blades cone up

Some time later, he attempts a single-engine takeoff

Doesn't make much sense that, how can he take off if the engine has already failed :p

What happened the machine at the start, did he get into VRS??

Dave

SASless

17th Jan 2009, 13:46

Combination of rough sea...gear down....low power margin (if any)...and a major brain infarction all at the same time!

The gear does not provide that much drag in reality....the Chinook does a grand running landing and running takeoff to water....smooth water...with both engines running. Not sure I would want to try a single engine takeoff however...unless you can hover.

If one takes on water inside the aircraft...then lowers the nose.....I can see where it might get awfully nose heavy in a hurry! I know of at least one UH-1H that was lost that way in Vietnam. Monsoon rain flooded the landing site....filled the low lying spot until there was about six inches of water inside the cabin and cockpit. Upon attempting a takeoff....the pilot lowered the nose and enough water flowed forward to cause the aircraft to nose into the water again but this time with substantial forward speed. Result was very similar to the video of this Russian aircraft.

We wound up slinging out a pile of wreckage instead of a wet soaked aircraft.

skadi

17th Jan 2009, 14:28

Quote:
Some time later, he attempts a single-engine takeoff
Doesn't make much sense that, how can he take off if the engine has already failed http://static.pprune.org/images/smilies/tongue.gif

ONE engine out of two failed! So an SEWTO ( Single Engine Water Take Off ) would eventually be possible. The danish and canadians practised that for training even with a real helicopter ( Seaking/ S61 ) and it works fine. It was a standard procedure during our simulatortraining on the Seaking.
After reducing the weight to the calculated SEWTO weight Speedselector full forward, gain max. waterspeed ( approx. 15 kts ) and pull collective to min. NR.

skadi

Lt.Fubar

17th Jan 2009, 15:06

I didn't seen crash report on that Russian Mi-14 so will not go to why it happened.

But:
Sea King is a lightweight helicopter, compared to Haze. Haze is more than twice as heavy while empty, with only around 18% more power. It can not take off on one engine. Not from water, not from airstrip.

Actually you can't maintain altitude above 1400 feet, and speed is reduced to 60 kts. 2225 HP* will only give you that much in 12 metric ton airftrame.

* The TW3-117M-III series engines have 5 distinct operation regimes:
1 and 2 - Cruise - producing 1200, and 1500 HP
3 - Nominal - producing 1700 HP - 60 minutes limit
4 - TakeOff-limited - 1950 HP - in this mode engine work if the other is inop, but with 6 minutes limit it will probably only get you to the ground/water, longer - it's a gamble.
5 - TakeOff - 2225 HP for limited period of time - as long as exhaust temp. is below 990*C (usually measured in seconds)

Dan Reno

17th Jan 2009, 15:55

Somehwere it was written that floats located forward of the sponsons on the fuselage would have prevented nose plowing during water taxiing.

MightyGem

17th Jan 2009, 23:58

did he get into VRS??

No, no where near it.

mickjoebill

17th Jan 2009, 23:59

When this video first came into the public spotlight the two different camera angles were neatly and seamlessly edited so that it appeared the elapsed time between initial impact and attempted takeoff was just a few seconds.

If there is a cut or change of angle we should not assume the action is continuous.

Mickjoebill

jimjim1

18th Jan 2009, 00:13

I noticed that when it turns over and the nose bobs partially out of the water that a jet of water comes out a what appears to be a circular hole, perhaps a few inches in diameter, on the bottom of the 'radome'.

I wondered if the cause of the take-off failure was that the radome contained a significant amount of water that had leaked past a displaced inspection cover or somesuch.

The water spout can be seen clearly on the video at second 13 (counts down) just above (on the image) the front port (on the machine) gear leg. Later at second 7, as the radome bobs out again the water has stopped and the hole can be seen as a black spot.

Perhaps the water can be seen earlier too (say second 16) but with the general splashing and the less tight camera zoom it is less certain.

Maybe its sonar and is designed to flood?

Lt.Fubar

18th Jan 2009, 00:50

That was Mi-14 PS - search and rescue version - no sonar, MAD or sonobuoy launch tubes on those, the bomb-bay is also reduced, although the radar is on its place. If that hole was the only one in the fiberglass radome it couldn't fill with water - it is watertight, and without a way for air to vent elsewhere - its pressure would minimize the leakage.

Will try to look for crash report on Russian sites, maybe it will shed some light.

Senior Pilot

18th Jan 2009, 02:45

Will try to look for crash report on Russian sites, maybe it will shed some light.

This was originally posted in 2006, in post #7 here (http://www.pprune.org/2852492-post7.html): a link that has some Russian TV commentary on the accident. Maybe Lt. Fubar can translate for us?

Lt.Fubar

18th Jan 2009, 10:50

I don't speak Russian and the Cyrillic alphabet looks to me like hieroglyphics, therefore I use online translators while searching eastern web sites. I will send it to someone who can... but don't get your hopes high, as this material is fresh after the crash, and what I understand (from similarieties between Polish and Rusian language) at that time their prosecutor was about to start investigation to find out if the cause of crash was a mechanic malfunction, and if the safety regulation were crossed.

I searched for crash report although as that aircraft belong to military - none was given to the public, for civilian crash investigation you can find info on Mak.ru (http://66.196.80.202/babelfish/translate_url_content?.intl=us&lp=ru_en&trurl=http%3a%2f%2fwww.mak.ru%2frussian%2frussian.html)site. For military.... well you need to be in it ;)

@Dan Reno - I don't think any additional floats would do anything more than add drag, this construction floats by itself, inflatable bladders on sponson sides are for more stability in such conditions (a side note: although they can be inflated with a bottle, the main system is compressed air from compressor - they will slowly deflate if the engines stop running). The limitations for performing water running takeoffs are:
- waves up to 2°
- wind speed up to 20kts
- forward speed no more than 8 kts
- weight no more than 12000kg (no load except for equipment and some fuel)

I've looked the manual for any note that lowering landing gear will increase stability on water and found none... and I don't think it will work that way.

Shawn Coyle

18th Jan 2009, 13:24

One of the things not mentioned here so far is the sea state. All the SEWTO practice done by the Canadians was with very small waves. I think the pilot got out of phase with the waves, and didn't realize that with the nose going down so far, he was out of options very quickly.
Increasing collective would only drive the nose down further - dynamic pitchover if we can coin a phrase.
This has also happened to two OH-58s on floats at the US Naval Test Pilot School, trying to do running takeoffs on the water (don't ask why - it was noted in at least one country's flight manuals as a prohibited maneuver) and the front of the skids got underwater, and over they went.

ecureilx

18th Jan 2009, 15:40

The mils, especially the Mi 8 and Mi 17, have a very very nose down attitude when taking off, and for the uninitiated it looks like the main rotors are about to touch ground when moving forward ...:}

The Mi8/17 has steps for the forward door, while the rear doors can be almost walk-in height ..

I was always amazed when these choppers transitioned, fearing they are gonna loose it ....

Lt.Fubar

18th Jan 2009, 15:55

That's why manual advises to keep 1/4th of rearward cyclic during takeoff, and perform running takeoffs with level attitude, especially avoiding rising main gear, but still rolling on the front, as in Mi-14 it is not very strong and may be damaged this way.

A lot of don'ts in those machines.

VfrpilotPB/2

19th Jan 2009, 16:30

When that sort of Heli has the sort of power being quoted, why was the pilot not able to just get up to max power similar to that required for a towering take off, and gently lift off?

Peter R-B
Vfr

Lt.Fubar

19th Jan 2009, 18:20

Only obvious reasons come to mind. Either they couldn't pull off so much power - any mechanical failure, or engines already running hot. Or it wouldn't do anything - overweight.

Pilot DAR

20th Jan 2009, 02:30

The gear does not provide that much drag in reality

I do not agree. I cannot speak for the Chinook. But, wheels down in the water with any forward speed is real trouble in a flying boat with wings, and flying boats with wings (and a tail) have much more authoritative pitch (nose up) control than a conventional helicopter.

I cannot see how the helicopter could manage any better that the flying boat. If you tried a wheels down takeoff in a flying boat or float plane it would go over, though probably with some warning to the pilot. He would have pitch control to use to resist the nose over, while he reduced the power.

With all the drag on the bottom, all the thrust at the top, and no ability to control forces in the whole aircraft pitch axis, it seems pitching over is inevitible for the helicopter, if you tried a running takeoff on water with the wheels down (those long looking dual nose wheels can't help either). Perhaps the Chinook can manage better because it is tandem rotor, and I presume has much greater pitch control.

I recall a spectacular photo of a Vertol 107 towing a load on the surface, it had an incredible nose low pitch attitude, and I presume was in stable flight. That photo makes me think that with a high "drag" force on the lower portion of the helicopter, it would like to assume a very nose low attitude to fine stable flight. This helicopter just found the water with the blades before it got to the stabilized nose low attitude. The forward sponsons of the Sea King having the bouyant effect forward of the C of G, is an interesting observation in light of the other considerations.

Pilot DAR

SASless

20th Jan 2009, 03:50

Couple of points...

The BV-107 photo taken on the North Slope provided a visual illiusion as the actual pitch angle was was less than it appeared.

The drag the landing gear would have at the 10-15 knots of water speed would be far less than at an airplane's takeoff speed of 70-90 knots.

On a Chinook....the allowable center of gravity travel is on the order of 144 inches depending upon the model of the aircraft....thus it has a full 12 feet of CG range. Add in the quad gear....spaced a long way apart and it does not want to tip forward like a tricycle geared aircraft.

In a boat hulled helicopter like the S-61.....I would imagine drag would be the issue and not control limitations. Perhaps Crab or some other 61 or Sea King pilot could enlighten us on that.

Perhaps control touch is more important than anything.....

YouTube - cubdriver749er.com - demo video 1 (http://www.youtube.com/watch?v=23P7TZVUhPc&feature=related)

YouTube - Landing on water without floats! (http://www.youtube.com/watch?v=01E_6oxvlQA&feature=related)

oleary

20th Jan 2009, 05:15

Yup, the 61 does a single engined water take-off just fine if you get the weight down a bit and you have the 140-1 or 2 engines. I don't know about the 110's.

At least the OKie 61's did.

And probably pulling the gear up for take-off would be good plan, too!

This is because the puppy can be notoriously nose heavy when taxiing (depending, of course, on cabin loading) for example, through snow or muck - which is kind of like taxiing on water. It is really easy to scuff the forward belly light under these conditions.

Anyway, trying a water take-off with the gear down requires a technique I don't have.

skadi

20th Jan 2009, 08:02

As far as i remember, the procedure for SEWTO ( Sea King ) was allways "gear up" to reduce drag / nose down moment! It was recommended to put the gear down if you have to float in the water to increase the stability ( lower C of G ), but for landing/ takeoff in the water allways gear up!

skadi

Darkhorse30

20th Jan 2009, 14:44

I have about 130 hours in a ASW Mi-14 and one of the systems on the aircraft is a door, window, radome, and bomb bay pneumatic seal that is supposed to be activated anytime over water. If the system is not activated, the radome will fill with water when you land in the drink and at 8.5 lbs. per gallon the weight it takes on will preclude any kind of take off. There is simply no way that enough aft cyclic control is available to stop the nose down pitching moment. Also, notice that the sponsone floats were inflated at some point which will allow for some lateral water stabilty, but not help a bit with pitch control. It appears that the seal, if installed and working was not operating since in one frame the left door is partially open. The pneumatic system seals all of the aircraft doors/openings at once.
I suspect that once she went into the water, it didn't matter what the crew did. The nose was going down.

Lt.Fubar

20th Jan 2009, 16:06

Can you please show me that pneumatic seal on this main door frame ?
http://img89.imageshack.us/img89/2069/dsc024010803195rj0.th.jpg (http://img89.imageshack.us/my.php?image=dsc024010803195rj0.jpg)

To my knowledge the whole radome is one piece - fiberglass composite, mounted to the fuselage with around 10 screws - between radome and fuselage there is rubber-like substance neatly sealling it off. The radar/avionics compartment is also sealed, just like the hydraulics that operate the bomb-bay door, that are located behind it. I may be wrong, but I think I would notice it.

Jackboot

20th Jan 2009, 16:20

Looks like he had insufficient power to hover, hence the heavy landing in the drink.

Was he possibly trying to achieve tranlational lift to get off again? The sea state didnt help him either.

Easy to be wise after the event but an abandoned take-off, followed by a significant offloading of weight - ships nearby etc. - might have saved the day.

He might well have been taking on water though, and took the decision to go as opposed to losing the aircraft.

It would be interesting to read a tranlation of the pilots report. Anybody know the telephone code for Siberia?

JB

Darkhorse30

20th Jan 2009, 17:50

LT FUBAR
I don't see it in this picture and it may be that this is a different version, I don't know. Ours had seals in the one and only passenger door. The door seal was mounted in the frame and surrounded the door. It, as well as the others, was activated by the pilot (left seat) using a round knob. The seals were swelled by compressed air from a tank that was fed by the compressor mounted on the main transmission. (Compressed air also powered the wheel brakes) These seals were located around each window in the cockpit, the radome, the bomb bay, as well as the door. Our aircraft was the ASW version and I assumed, perhaps wrongly that the accident aircraft also had the seals. I know that there was a SAR version of the MI-14 and I would think that they would want the seals also. Ours had no inspection port.
As for the radome, you are right about the numerous screws or bolts holding the fiberglass dome. But ours had the inflatble seal.
When we flew overwater, the drill was to shut all the openings, seal them, and insert air conditioner hoses into our flight suits since we didn't have the appropriate air conditioned suits.
In my opinion, if there was nothing more than just rubber gunk around the dome to seal out water, just a little deterioration and some hefty water pressure would cause a major leak.

Lt.Fubar

20th Jan 2009, 18:23

The picture I posted is from Polish Navy Mi-14PS (#1016) - SAR version similar to the one that crashed (manufactured in 1983). There are no inflatable seals around doors. It is probable there is positive pressure inside the avionics (radar) compartment, but no inflatable seals there as well. Although our ASW Mi-14PLs do have a seal around the door, but I have no klowledge if it is in fact inflatable (didn't looked that way).

Darkhorse30

20th Jan 2009, 18:38

Lt. Fubar
I honestly don't remember the designation of ours. It has been several years since I flew it. The ones I have seen on the internet don't show enough detail to solve the confusion. Maybe some one you know around these aircraft will remember the seal inflation. On youtube there are several videos showing Mi-14's in various stages of water landings and they show a lot of water coming up to the windshield when moving forward in the water. That big radome doesn't help much.

heli1

21st Jan 2009, 07:59

I suspect Dark Horse was flying an ex-East German Mi-14 ,several of which were sold for potential firefighting and other uses ,although all/most ended up abandoned.However I am not aware that the East german aircraft were any different from the Polish examples

Lt Fulbar...How about bringing one to the HeliDays event in the UK this year....I know the organisers always welcome a Polish contingent .

ecureilx

21st Jan 2009, 08:16

DarkHorse, Is this the video you were referring to ??

YouTube - Mil Mi-14 Haze (http://www.youtube.com/watch?v=3lONe0FyTzo&feature=related)

Lt.Fubar

21st Jan 2009, 08:32

Heli1, It would be interesting to show those machines there, unfortunately it is a bit late. It's becoming a problem to keep them running, they're a bit short on life span, spares and crews.

For ASW ones, from 11 available - 3 were modernized so far, 2 others are worked on, so maybe one of those could fly there, if a spare crew would be find. The SAR ones are off the limits, although showing one beside S-92, or Irish S-61 would be interesting. Unfortunately last year one (#5137) reached its life limit (28 years) and had to be scraped, two other (#1013 and #1016), are not far behind it, they should be decommissioned next year. One newer ASW was sent to be rebuild to perform SAR missions, but it was siting there waiting for parts from the scraped one - I asume it will get its doors, winch, and comunication equipment, but the whole thing is not set in stone yet.

There is going to be a purchase of new helicopters soon, meant for ASW/ASuW, SAR, CSAR and troop transport roles, but it's geting late :ugh: . There were some talks about making the lifespan of SAR machines 4 years longer - to equal to the ASW variant which can fly for 32 years, but with all the politics crap right now - it's not likely. Currently the whole Polish coast is secured by two Mi-14PS, and 7 W-3RM "Anaconda", unfortunatly those W-3 were not design to work in that corosive environment, and are a bit small, and not very ergonomic (next one who say AW139 is not suited for maritime SAR - think off those ;) ).

JohnDixson

21st Jan 2009, 12:55

In 1964, I picked up a new Chinook in Philadelphia that had been modified for water operations. It had a small dam that could be temporarily installed in the rear, thus allowing the ramp to be lowered while on the water and disembark a raft etc.

Part of the exercise was to conduct some simulated single engine landings and takeoffs. The landings were uneventful, with the large undersurface acting as a terrific brake. Lots of water spray up near the engine intakes, but no stalls. The takeoff was a problem, though, because just as you got to about 15 kts, the lower right cockpit window failed, and with that aft-slanting metal surface just forward and below the pedals, the water was efficiently sluiced right into the pilots chest. End of simulated single engine takeoff evaluation.

Thanks,
John Dixson

Darkhorse30

21st Jan 2009, 13:39

ecureilx,
That video is the one. There are a few others. Our aircraft was definitely ASW. It had all sorts of ASW stuff in the back and no rescue hoist. Also, It appears from the video that the crew/passenger door on the left side is bigger on the SAR than on our ASW aircraft.
As you can tell from the video, the nose gets a good washing at just about any forward speed in the water. If the crew in the crash video didn't have the front sealed she is going to take on water. Just stating the obvious.

ARRAKIS

21st Jan 2009, 19:17

There is going to be a purchase of new helicopters soon, meant for ASW/ASuW, SAR, CSAR and troop transport roles, but it's geting late

Lt Fubar,
I would say, you are overoptimistic, but only time will tell.

Regarding the Mi-14 crash, after the Haze overturned, fortunately it stayed afloat. 12 out of 13 pax/crew onboard survived the crash.

Arrakis

unstable load

22nd Jan 2009, 01:24

Considering that he looked like he was taxying at the time could it not be something like nose-tuck that caused the prang? I remember talking to an old 61 pilot who had done water landings and he mentioned nose-tuck as a potential problem in water ops.
If the pilot is not experienced or trained for it, then he could fall for that one.