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Old 14th Dec 2012, 10:21   #41 (permalink)
 
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Shawn,

Do you have this problem?



Surprising statement given that the aircraft is still on the bottom of the sea.

With due respect maybe it should be left to the accident investigators which apparently you are not.
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Old 14th Dec 2012, 11:21   #42 (permalink)
 
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The recovery is planned for tomorrow, divers are preparing the wreck for lifting right now:
The recovery vessel "Scharhörn" returned to the crashsite after picking up divers and material in the nearby harbour of Neustadt this morning

Vermisster Hubschrauber: Bergung beginnt - HL-live.de

skadi

Last edited by skadi; 14th Dec 2012 at 11:24.
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Old 14th Dec 2012, 12:40   #43 (permalink)
 
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Latest News on a local radio station "NDR 1 Welle Nord" :
Two bodys were located in the area of the downed helicopter at 20m ( 60ft ) below the surface. The helicopter is relatively undamaged, only the blades were torn off.

skadi
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Old 14th Dec 2012, 14:21   #44 (permalink)
 
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My statement about the hydraulics is based on reviewing a whole lot of AS 350 accidents where control was clearly a problem (many where the NTSB absolutely didn't consider that), as well as reviewing a massive stack of Service Difficulty Reports that relate to hydraulic actuator problems.
In one of the accidents I was involved with a hydraulic actuator clearly failed the acceptance criteria, yet the NTSB said there was no issue.
If I were an accident investigator for a national authority, I'd have the actuators checked thoroughly on every AS350 accident unless it was clearly some other issue.
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Old 14th Dec 2012, 14:23   #45 (permalink)
 
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RVDT:
No - I don't think Bell is perfect.
And that's not me in the picture.
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Old 15th Dec 2012, 08:51   #46 (permalink)
 
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Latest news say that they plan to recover the wreck today, along with the two bodies that were found around 50 m away.
The doors of the helicopter were found to be open, when military divers discovered the wreck two days ago.
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Old 15th Dec 2012, 09:22   #47 (permalink)
 
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@ Shawn; could you please elaborate on the AS 350 hydraulic system, and particularly the actuators? Thanks!
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Old 15th Dec 2012, 09:28   #48 (permalink)
 
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Alouette: As you await SC's response you might find this thread to be of interest: As350 Hydraulic System Failures: too many??
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Old 15th Dec 2012, 15:22   #49 (permalink)
 
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Alouette:
The AS-350 hydraulic system (single actuator version) is pretty unique in the helicopter world. It's driven by a belt (which for the first 20 years of it's life failed with monotonous regularity), and has a very complex training procedure for simulating hydraulics off. It also has probably the most complex pre-takeoff checking procedure to make sure things are operating properly.

As far as other failures go, I've not heard of any other helicopter having hard-overs in the hydraulic system with the frequency that the AS-350 series has. I've had pilots personally report to me that they'd just turned the hydraulics back on and had the cyclic motor to the lateral stop and stay there for 30 seconds.
I could go on - a brief survey of service difficulty reports showed a huge number of servos removed for motoring or binding, and certainly not meeting time between overhaul.
My intention is suggesting that hydraulic actuators be looked at in detail is that at first glance there may appear to be nothing wrong by looking at the outside of the actuator - it's only in teardown that problems might be found.
I'm not pre-judging the cause of the accident, merely trying to make sure that a potential cause might be missed.
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Old 15th Dec 2012, 15:55   #50 (permalink)
 
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Shawn,

Might I suggest the other thread to keep posting your critisism of the design of the hyd system of the AS350, or even a new one, as your reflctions from the past don't really fit in this thread.
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Old 15th Dec 2012, 16:45   #51 (permalink)
 
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According to some medias the most famous german counterterrorism unit GSG9 and some other special forces units practiced while the crash happened direct near the accident site. They used according to a police spokesman some different ways of electronic warfare. The spokesman confirmed only GPS and GSM jammers and refused further informations due to the high secret level. The Spokesman told the medias none of the special forces took notice the crashing AS350 in visual range to the practice.

The recovered wreck of the AS350 is now on storage in an military area.

Last edited by tecpilot; 15th Dec 2012 at 17:16.
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Old 15th Dec 2012, 18:33   #52 (permalink)
 
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First pics of the recovered wreck:Vermissten Hubschrauber aus der Ostsee geborgen - HL-live.de It does indeed look like a controlled ditching...



The area of the police practice was about 4nm away from the crashsite and was protected by a temporary reserved airspace ( NOTAM ).

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Old 15th Dec 2012, 19:03   #53 (permalink)
 
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Quote:
The area of the police practice was about 4nm away from the crashsite and was protected by a temporary reserved airspace ( NOTAM ).
Skadi, how large was this tempo restricted area? Could it have affected the crew's decision to take a "shortcut" and accept the 10-11 km leap over the water, instead of just flying west of the restricted area at Hansa Park?
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Old 15th Dec 2012, 20:03   #54 (permalink)
 
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@TechPilot:

This practice area was a state fair, a protected area surrounded by fences and rollercoasters and god knows what else.

They maybe might have seen the helicopter descend, but surely not crash.
And as @skadi wrote, it was around 4 nm away.

Secondly, according to german news reports, they were indeed using GSM-jammers, but probably not at the time of the accident. And even if, what should be the implications of a GSM-jammer to an aircraft?

@TaT: Coming from Lübeck, they could have chosen a route passing the TRA on either side.
Yes, flying this route is slightly longer and lead them over the sea, but not by much.

@all: If you look up Google Maps, go to Lübeck Airport (Lübeck Blankensee).
Due north you´ll find "Sierksdorf" right on the shore of the Lübeck Bight.
Zoom in and a mile or so NE you´ll find "Hansapark". This is were the special forces were practicing.
The aircraft crashed due ESE of "Hansapark".

From my point of view (I regularly fly in this area) a sensible decision would have been to head NNW, up to Fehmarn and cross the Baltic Sea there.
That´s the so-called "Flying Bird Line", offering the shortest hop over the water. Surely birds know what they do.

The duty SAR crew was on scene not long after the alert (stationed at Warnemünde near Rostock), but nothing was found. I do not know and do not wish to report how long it´s taken for the radar operator to miss the aircraft and initiate the appropriate action.
That will be published by the BFU, the German Air Accident Investigation Branch in due course.

Thomas

EDIT: Kieler Nachrichten (Kiel News) reporting the following:
"das während der Übung keine Störsender eingesetzt wurden, außer am 6. Dezember für 15 Minuten in der Zeit von 01.05 Uhr bis ca. 01.20 Uhr ein GSM-Jammer im Rahmen des Zugriffs. Dieses Gerät störte laut Polizei lediglich die GSM Frequenzen in einem horizontal von Norden nach Süden verlaufenden etwa 300 Meter langen und 30 Meter breiten Korridor."

During the exercise there were no jammers used, except for the 6th Dec. for 15 min. between 01:05 and 01:20. That was a GSM jammer, jamming in a corridor running N-S, about 300m long and 30m wide.

Last edited by Thone1; 15th Dec 2012 at 20:12. Reason: added info
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Old 15th Dec 2012, 21:02   #55 (permalink)
 
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Lack of Damage

Anyone notice the complete lack of rotor damage? Cabin intact...skids still attached? Without knowing all the facts - could this be a water entry from the hover with very low rotor speed?
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Old 15th Dec 2012, 22:10   #56 (permalink)
 
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Quote:
Lack of Damage
Anyone notice the complete lack of rotor damage? Cabin intact...skids still attached? Without knowing all the facts - could this be a water entry from the hover with very low rotor speed?
And, perhaps the crew were non swimmers, but a hasty decision indeed if they embarked on this course without life jackets???
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Old 16th Dec 2012, 01:09   #57 (permalink)
 
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There are some damage to the main rotor head but much less than I would have expected. They must have hit the water with very little forward speed.
I have seen the result of a ditching with the 350 and the damage to the main rotor blades was much more severe.

I do not want to speculate regarding the cause of this accident but I would like to comment on Shawns postings regarding hydraulic failure.
I have been around the 350 for quite some time and a considerably number of flying hours and have never experienced a hydraulic failure, even in the old days.
If you do a tight right turn "fighter style" with a high degree of bank you may experience servo transparancy or "jack stall" which at low altitude is deadly but on a straight and level flight with "normal" control inputs no way.
We are of course training on hydraulic failure and if you slow it down to 60-65 knots even a girl can fly it without hydraulics. But since the americans love dual hydraulics maybe that is what is causing the problem? Here in Europe single hydraulic is common.

Statement from Shawn: "I could go on - a brief survey of service difficulty reports showed a huge number of servos removed for motoring or binding, and certainly not meeting time between overhaul."
Well, the 1800 hrs TBO Dunlop servos has never caused us any problems. The 3000 hrs TBO SAMM servos has been another matter, we have had cases where they have started leaking but that does'nt mean that you get a hydraulic failure. Maybe you americans disregard the TBO and run the servos "on condition"? With your 1672 post do you know anything about the AS350 or helicopters? Or are you a "pain in the ass" interested?

This is a very tragic accident and I will follow the result of the investigation with great interest.

I have flown the same route numerous times and Lübeck has been the preferred fuel and coffe stop. But since I feel uncomfortable flying over water we have always been flying over land to Puttgarden and then to Rødby in Denmark. There are ferries going non-stop there so in case of problems you will hopefully be picked up wearing a life-jacket. It's a matter of reducing the exposure time.

Last edited by Bell214B; 16th Dec 2012 at 02:13.
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Old 16th Dec 2012, 02:31   #58 (permalink)
 
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Bell 214B:
I do know a thing or two about helicopters, and have worked on several AS350 accidents. I don't make statements lightly on this forum.
My suggestion was and is that in any AS350 accident that doesn't have obvious other causes that the hydraulic actuators should be carefully checked.
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Old 16th Dec 2012, 02:39   #59 (permalink)
 
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The helicopter has been salvaged so at least they will find out what has not happened.
But since you are an investigator you have to have an open mind. Don't jump to conclutions.

Last edited by Bell214B; 16th Dec 2012 at 02:53.
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Old 16th Dec 2012, 04:42   #60 (permalink)
 
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@ Savoia; Thanks for providing the link!

@ Shawn; thanks for the feedback. Much appreciated!

Last edited by alouette; 16th Dec 2012 at 04:44.
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