Greek Apache Helicopter crashes into sea.

[heliboy999]

Cant understand the text but it shows a Greek Apache helicopter crashing into the water after what looks like a wingover. Anyone shed some more light on this?

???? ????? ?? A????? (http://www.zougla.gr/greece/article/etsi-epese-to-apatsi)

HB999

[Same again]

after what looks like a wingover.

A pity that no-one had shown them how to do one properly.

[NRDK]

About 5-7 seconds into the video it looks like a little flash out of the exhaust area?

That aside, rubbish wing over, started low ended lower:D

[Self loading bear]

Google translate
(But that doesn't matter as it written by a journalist anyway)

SLB

Shocking images recorded at the video of the zougla.gr and exclusively captures the last few seconds before and after the fall of the helicopter (AH-64D) of Army Aviation in Vrasna beach (bay Korfanou) in Thessaloniki.

Under unclear circumstances so far, while the Apache is running low flight over homes and beach bathers falls violently sea. One operator was able to extricate himself in time, but the left unharmed with the help of colleagues.

According to zougla.gr information, the commander of the helicopter bearing the rank of major and the co-pilot the rank of captain. Both are experienced pilots with many hours of flight (night, week, etc.). The Apache belongs to the 2nd Battalion attack helicopters of the 1st Army Aviation Brigade.

[MightyGem]

but it shows a Greek Apache helicopter crashing into the water
All I get is a black screen with those videos.

Engine failure apparently:
Apache Helicopter Crash in Northern Greece, Survivors Reported | GreekReporter.com (http://greece.greekreporter.com/2016/09/20/apache-helicopter-force-lands-in-northern-greece-survivors-reported/)

[Cows getting bigger]

Fly like a tw@, crash like a tw@

[NRDK]

That will be the flash out the back at low level over the lake. Nice pull up shortly after, but wtf did he try the aggressive wing over for? Unnecessary loss of an expensive aircraft. Never mind, Greece can afford it.:8

[John Eacott]

The video:

DSv-rvGrkgU

[Rotate too late]

Just where on the scale of "this will not end in tears" did he need to be, to realise that was not a good idea. I've heard he had third party only as well.....:{

[AnFI]

newspaper ( :rolleyes: ) says engine failure

er is this a single / twin discussion then? :oh:

[MightyGem]

The video:
Thanks for that, John.

[sporg]

If you look at the pictures in this article, you will see why the pilot would not want to crash on land, and forced his helicopter back over the sea: The beach is full of people.
???? ????? ?? A????? (http://www.zougla.gr/greece/article/etsi-epese-to-apatsi)

http://www.zougla.gr/image.ashx?fid=2055652

To me it looks (and sounds) like engine failure around 0:06 (https://youtu.be/DSv-rvGrkgU?t=5) in the video, followed by power loss, and high speed autorotation landing attempt.

[212man]

Nice pull up shortly after, but wtf did he try the aggressive wing over for?

I don't see the actual reversal in the video so how do you know how aggressive it was? Looks like he was trying to outdo his mate, who was successful, although maybe not his mate anymore as he thought it better to fly away rather than hover over the wreck to check if the crew were ok!!

[Same again]

Engine failure - of course it was. Very brave of them to continue with a wingover on one engine. Ouzo and medals on return to base.

[cattletruck]

Obviously not much room left for error to pull off such a manoeuvre.

The person filming summed it accurately by referring to the person in control as a "Malaka" (W@nker).

[NRDK]

212. I was just commenting on the 'need' to continue a climb and turn back? After a possible engine problem. Perhaps he didn't correctly recognise it? Plenty of people have not noticed until too late that they have a problem. Aggressive or not? Well had it been gentle he should have had good VY speed/height and no need for dunker drills. " Malaka" is right.

[MamaPut]

The crew, formerly Major Disaster and Captain Catastrophe (now Corporal Punishment and Private Parts), get a perfect 10 10 for September's Wizard Prang competition! Despite his kipper having been smoked, I'll wager he was not back for breakfast

[ShyTorque]

Looks like an ad-hoc and probably unauthorised attempt at impressing bystanders. How many more people are going to kill and maim themselves and crew members by attempting wingovers in such an incompetent manner?

Another stupid and unnecessary waste.

If this was the RAF, they'd have to promote him now....

[212man]

212. I was just commenting on the 'need' to continue a climb and turn back? After a possible engine problem.
Well clearly it was just a pair trying to impress the bystanders - one crashed and the other one didn't....Pretty sure no engine problems were involved.

[F-16GUY]

Well clearly it was just a pair trying to impress the bystanders - one crashed and the other one didn't....Pretty sure no engine problems were involved.
212man,

Care to explain the flame out the back of the engine at time 0:06 in the video? Are you still pretty sure they had no engine problems?

[chopjock]

Care to explain the flame out the back of the engine at time 0:06 in the video? Are you still pretty sure they had no engine problems?

Also over pitching / high coning angle just before ditching… suggesting loss of power.

[SilsoeSid]

Could that 'flame' simply be a strobe flash and the coming angle simply the result of pulling anything that's left to get away from the water?

[212man]

Could that 'flame' simply be a strobe flash and the coming angle simply the result of pulling anything that's left to get away from the water?

I thought it was strobe the first time I saw it. but a look at images online does not show one being there. Also the wrong side for the sun to have reflected off something.

However, if it was a flame I'm pretty sure there would have been an audible retort too, so hard to imagine why they would have continued?

[chopjock]

However, if it was a flame I'm pretty sure there would have been an audible retort too, so hard to imagine why they would have continued?

One thing is for sure, when flying that low with your feet wet your eyes will be outside and not on the instruments. So any flashing lights may have been un noticed...

[SilsoeSid]

Ok, so the online expert says it's not a strobe and tells us that its the wrong side to be a reflection from the Sun (which is clearly to the 9 0'clock of scene)....

http://i52.photobucket.com/albums/g11/silsoesid/Screen%20Shot%202016-09-21%20at%2013.57.46_zpsx88objwh.png

... no smoke, no change of flight path and the manoeuvre continued with, it must have been a bright white no cockpit indications or warnings engine flame then :rolleyes:

[212man]

so the online expert says it's not a strobe and tells us that its the wrong side to be a reflection from the Sun (which is clearly to the 9 0'clock of scene)....

Not sure how the above contradicts what I said? The aircraft as viewed is in shadow, and looking at the second aircraft (and photographs) there is no strobe in that location.

Actually, looking at the screen shot it looks more like a reflection from something on the far shore - car maybe?

[Lonewolf_50]

My old wing commander would probably have looked at this low pass near the beach and given the aircraft commander an icy look, asking him if he knew what flat hatting is and why it's not kosher. Not sure how they feel about such things in the Greek forces.

[tottigol]

Reminds me of this other f*#k-up

https://www.youtube.com/watch?v=bsnH2OzNPzo

:E

[ShyTorque]

A steep wing over and course reversal has never featured in any engine failure drill I've ever come across in the thirty seven years I've been flying rotary wing aircraft. A gentle climb to a safe altitude would have been a more normal way to begin dealing with any engine malfunction.

[nowherespecial]

Can someone share a screengrab of this smoke? I can't find it anywhere in the video at 6 secs in. Could be that it's blended in to the back ground, what with him flying 5 ft above the sea and stuff......

Certainly looks like a 'stupid pilot' and not a mechanical failure accident IMHO...

:ugh:

[ShyTorque]

Here's another similar accident:

b8O3JdO0lAg

This chap was slightly luckier. Let's hope he reported it so the aircraft could be checked over....

CqT6VfOBsIk

[SilsoeSid]

Hey 212man,
Actually, looking at the screen shot it looks more like a reflection from something on the far shore - car maybe?

... perhaps it was a flash from the Orford Ness lighthouse :rolleyes:

[Wageslave]

... perhaps it was a flash from the Orford Ness lighthouse

No chance. It closed a couple of years ago.

[SilsoeSid]

Exactly ....

[212man]

Hey 212man,


... perhaps it was a flash from the Orford Ness lighthouse :rolleyes:

Keep taking the happy pills!

[TwinHueyMan]

http://militaryedge.org/wp-content/uploads/2013/11/AH_64D_UAE.jpg

It's a strobe. D's and E's have em on both engine cowlings.

They messed up. Plain and simple. But well done convincing the boss it was an engine failure!

Mike

[Hueymeister]

Bunch of people on a beach...

My money's on, cowboy low-level wazz-ex, aggressive pull-up into an attempted wingover. Insufficient height above terra firma reached, resulting impact..luckily, in some ways into water. Their dunker drills now up-to-date.:sad::=:eek:

He opted for engine failure...he should have gone with 'I saw a suspicious vehicle at Ballywhat'sitsname and in manoeuvering crashed in what might have been a wing-over thingy, kinda' He might make 2 star too!

[HEDP]

Interesting!

I am not sure that you can draw any conclusion from this video at all!

The first low level helicopter is a Delta model whilst the second clip in the pull up is an Alpha model followed by the third aircraft crashing is a Delta model.

There are several aircraft being filmed and it may be that the last aircraft is conducting a flyaway after engine failure and is unrelated in dynamics to the other two in the video.

Thoughts?

[TwinHueyMan]

I think it was just two. Both zoomed at the shore low level, cam saw 1 pull up , panned to 2 (that did a better maneuver) then back to 1 as they tried to pull out of their messed up RTT. More aggressive than the A model did and from lower altitude, with that big honking FCR on top and all the "longbow" crap... No wonder #1 stuffed it up.

When will crapache drivers stop thinking they are fighter pilots? D's and E's are heavy as hell and don't have the cyclic authority at low airspeed/high GW that they think they do.

Mike

[Delta Torque]

Yet another chandelle/wingover/return to target gone wrong. Rolls out of the manouvre with a high rate of descent, no altitude left to recover, honks in the power and applies aft cyclic. Result is a high coning angle and an attitude change before impact. Bah.

[Two's in]

The Exercise 42 (Wazzing and Zooming) run in was all the evidence needed to predict exactly how that was going to end up. They are not the first and sadly won't be the last.

[Max Contingency]

Hello every body peeps. That's the ending of me demonstration on what happens when you roll out down winds with no speed and high rate of descents innit?

[Frying Pan]

Oh well, if the pilot struggles to find work after, they should head South. I understand a vacancy or two may exist in Kenya flying the 139. The skill set appears fairly similar. :D

[SASless]

Surely it was a dual engine failure caused by water ingestion!

[AnFI]

dTq
Interesting youtube is littered with these 'high speed stall' accidents

The point about coning angle is really interesting. There is effectively a conning angle at which a disk is in effect stalled, regardless of RRPM.

RRPM 'cancels out of the maths' when you look for stall.

[megan]

There is effectively a conning angle at which a disk is in effect stalled, regardless of RRPM.Substantiation by a technical paper please.

[AnFI]

megan

cone is proportional to the ratio of Lift (L) to Centripetal Force (Cf)
both L and Cf are proportional to RRPM^2

take a helicopter in the hover at low load and low RRPM (such that it is very close to stall AoA)
measure the cone
if load is increased the RRPM has to be increased to increase Lift
the AoA remains just short of stall and the coning angle is unchanged.
that coning angle is the coning angle just short of stall

(get well soon NL)

[212man]

I should stick to your multi-engine rants and steer away from rotor dynamics!

[AnFI]

212? u don't understand that?

[megan]

Like 212man suggests, your explanation doesn't even get close to passing the smell test. As I said, technical paper please.

[Al-bert]

who cares about coning angles? He fecked up a simple wing over - too low and ended up down wind - next!

[SASless]

I hate to inject technical questions into a thread here at Rotorheads but perhaps this is the time.

The Huey Cobra (for sure the Two Bladed Head models) had a tendency to do exactly what the Greek Apache did....smack the ground with the Collective Lever well up under the Pilot's Arm Pit while the Cyclic was nudging his Wedding Tackle.

You reckon the Apache Rotor system and flight control linkages might be susceptible to the same sort of thing?

Thinking "Pitch Cone Coupling" which is a section of the AH-1S Flight Manual contained at the Link below.

https://books.google.com/books?id=pXg-AAAAYAAJ&pg=SA8-PA14&lpg=SA8-PA14&dq=pitch+cone+coupling&source=bl&ots=ZjfBWAD6i9&sig=FJ2rVWKdVDbMVRk3xeN2jPFZdzE&hl=en&sa=X&ved=0ahUKEwjm4qX-zavPAhVDOSYKHfLiCjoQ6AEIggEwGA#v=onepage&q=pitch%20cone%20coupling&f=false

[LRP]

I hate to inject technical questions into a thread here at Rotorheads but perhaps this is the time.

The Huey Cobra (for sure the Two Bladed Head models) had a tendency to do exactly what the Greek Apache did....smack the ground with the Collective Lever well up under the Pilot's Arm Pit while the Cyclic was nudging his Wedding Tackle.

You reckon the Apache Rotor system and flight control linkages might be susceptible to the same sort of thing?

Thinking "Pitch Cone Coupling" which is a section of the AH-1S Flight Manual contained at the Link below.

https://books.google.com/books?id=pXg-AAAAYAAJ&pg=SA8-PA14&lpg=SA8-PA14&dq=pitch+cone+coupling&source=bl&ots=ZjfBWAD6i9&sig=FJ2rVWKdVDbMVRk3xeN2jPFZdzE&hl=en&sa=X&ved=0ahUKEwjm4qX-zavPAhVDOSYKHfLiCjoQ6AEIggEwGA#v=onepage&q=pitch%20cone%20coupling&f=false
The AH-1G/S used the 540 rotor system, as did the UH-1C/M. Pitch cone coupling was a feature of that system due to the flexure plate. The AH-64 uses a conventional articulating system.

[Vertical Freedom]

Same Guys where flying the 139 in Afrika just a few weeks ago, got a quick reassignment, then (another) OOOPS, who's gonna employ them now? :ugh:

[JohnDixson]

SAS, I believe that LRP has the correct picture re the UH-1C and subsequent Bell rotors that incorporated pitch/cone coupling by design.

This particular AH-64 video reminds of several others:
1. BO-105 accident with Seifried Hoffman flying, in New Jersey, I believe.
2. Last year's NH-90 crash into a lake.
3. The S-67 accident practicing the demonstration routine at Farnborough 1974.
4. A similar UH-60 "incident" flown by a US Army crew and I can't remember the time, but it was filmed and SA got the blades back. An "almost " version of the first three. The aircraft is seen doing a vertical type manuever and the pullout is at first obscured from the camera by a tree line, and then, just when you'd expect to see the smoke, the ship reappears.

The issues in 3 and 4 were looked into in detail, and I'm suggesting that the first two are similar. It is altogether both possible, and easy, when throwing a helicopter around close to the ground, to put the machine into a position where the application of maximum power/collective and appropriate cyclic input is insufficient to sufficiently change the flight path of the machine given the altitude remaining. A related consideration is that there is sufficient collective range in most ( if not all ) machines at the speeds noted in these examples ( and the Apache accident as well ) such that application of full collective will demand more than the power available, resulting in rotor droop. With rotor lift being a function of the velocity squared, this can really aggravate an already bad situation.

In the case of the S-67, the video showed extremely high flapping/cloning prior to impact. In the case of the Army UH-60, each of the rotor blades had wrinkled trailing edges, the result of aft damper stop contact. Damper lag angle in an articulated head is a pretty much linear function with power: higher power=increased lag angle.

There may be other factors involved in this Apache accident, rendering the above thoughts irrelevant. Stuff happens: I recall the story of an accident that occurred with a UH-2 Kaman machine where a very high speed crash was finally attributed to one of the pilots heels getting sandwiched into the base of the cyclic.

[SASless]

I grasp what you have to say Brother Dixson....having done some investigative flying in a Hughes 500D one morning on Unga Island, Alaska.

What I discerned is how critical the last three feet of height above the surface of a saltwater inlet can be when performing such maneuvers. I you compound what you describe by adding in the G Loading that one can apply to the Rotors and Head before reaching a structural limit....which can be a consideration....it is easy to find oneself wishing there was more clear space beneath the landing gear.

As one discovers all those limits coming into place...it seems religious dedication as a philosophic convention can also permeate to one's cognitive thoughts as well.

I suppose I am not the only pilot ever heard to utter the words...."Thank You Jesus!" in similar circumstances after grasping the Earth was getting further away and all the component parts of the aircraft less a bit of seat cushion were still doing their job.

[AnFI]

SASless re post 53
no
but it is alluded to in 8-36 in that manual example, refered to as mushing
its quite clear that folk dont understand what happens when you pull excess g
they seem to think it's about judging your trajectory to not hit the ground
whereas the disk making less total rotor thrust the more you (attempt to) pull (g) is not taught

megan
write your own paper

u can see the coning angle of the crashing apache is v high
the pilot pitch up, to pull more g, just reduces the TRT
this is a surprise to the pilot
pulling the lever up also has the opposite effect
he cannot alter his path at the rate he wants or is accustomed to being able to

there are many accidents from this phenomenon

mushing
pull more get less

it would be called high speed stall in an aeroplane and causes a similar large number of crashes

[212man]

212? u don't understand that?
I understand that you have edited your post several times and the latest iteration is rather different from the first.

it would be called high speed stall in an aeroplane and causes a similar large number of crashes

Oh yes, the accident reports are littered with them.....I think you mean 'accelerated stall' though.

Interesting to look down the original link and see some stills of a CH-47 also doing some kind of display - either it was an officially sanctioned event, or maybe a routine infarction now caught on camera?

[SASless]

"Mushing" must be a single engine term.....although Dog Sledders have been known to use that to describe their mode of transportation.

[Delta Torque]

Well, the two major factors here are the excessive rate of descent, and the lack of altitude to recover. The natural tendency to apply aft cyclic only results in a pitch up attitude change, the panic induced collective increase results in a high coning angle, and less disc area to produce lift. Another 100 ft or so, and they might have gotten away with it.

[AnFI]

reduced disk area negligable 2nd order effect

a/c pitch up at speed normally changes the flight path in part by increasing the angles of attack anf TRT
but once you arrive near the critical cone angle then an increase in pitch rate will have the opposite effect and TRT will counterintuitively reduce again
rather annoyingly for this and especially (many other) pilots at high DAs

(critical cone angle is less at increased DA)