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View Full Version : CHC Helibras EC225 Heavy Landing


terminus mos
20th Dec 2014, 04:16
A very crinkled tail boom on this EC225

From Airbus Helicopters

Airbus Helicopters was informed of a hard landing of an EC225 helicopter on an offshore platform off the coast of Brazil.
The hard landing did not cause harm to the passengers but did, however, result in structural damage to the aircraft which prevents it from flying in its current state.

A team composed of customer representatives and Airbus Helicopters personnel have arrived on-site to observe the initial findings and support the formal investigation. Preliminary analysis of available HUMS data conducted jointly between Airbus Helicopters and Turbomeca:

- Showed no HUMS threshold exceedance (including MOD45 which is monitoring the MGB vertical shaft)
- Shows evidence of possible engine compressor stall (“popping”), just before the crew decided to land.

This type of engine compressor stall (« Popping ») is a known transient phenomena on turbine helicopters. It is characterized by a noise which can be followed by transient vibrations. In itself, such “popping” does not represent any direct risk to subsequent continuation of the flight.
An information Notice on compressor stall describing the phenomena and both operational and maintenance recommendations is currently being prepared and will be issued over the next days.

Further analysis of the available data will be ongoing and Airbus Helicopters will keep you informed as relevant information emerges from the investigation.

malabo
20th Dec 2014, 05:31
So who is doing the investigation, CHC, Brazilian CAA, Airbus (desperately trying to salvage the reputation of the 225), Turbomeca with their compressor stall prone engines? Even if an engine completely flamed out, wouldn't the profile provide for a cushioned landing with the remaining engine and rotor energy?

Oh, wait, Airbus says compressor stalls are of no consequence anyway. And that it is not a risk to flight and that the crew subsequently "crinkled" the tailboom after deciding to land. Must be a story there somewhere, doesn't add up.

Anybody got pitchers?

HeliComparator
20th Dec 2014, 10:42
Well my reading of it would be an implied over-reaction by the crew. I don't think the Makila 2A1 is particularly prone to compressor stall, less so than for example the 1A2, and unlike certain far-west engine manufacturers, Makila don't consider it to be a catastrophe if it does happen. So maybe (speculation) it is just about crew awareness of the nature of the beast they are flying.

twisted wrench
20th Dec 2014, 11:41
Someone should change the Header, is not a Helibras 225 but a Airbus 225.

Helibras up until now do not assemble the civil versions only the Military 725´s for the Brazil Navy.

terminus mos
20th Dec 2014, 12:41
It says CHC Helibras EC225.

CHC don't assemble EC225s either, CHC Helibras or Helibras CHC are the Operator.

212man
20th Dec 2014, 12:55
Who's the client?

Variable Load
20th Dec 2014, 13:02
Makila 2A1 is particularly prone to compressor stall

In tropical climates there are at least two occurrences every week with one operator.

No doubt AH will issue something to say "ignore the problem", just as they have for poor Power Assurance figures.

voando
20th Dec 2014, 13:04
Petrobras are the client.

NickLappos
20th Dec 2014, 13:40
It's a good idea to blame the pilots when you have virtually no facts. Saves the bother of actually understanding what happened. I am glad to see HC has learned nothing in the last decade.

JohnDixson
20th Dec 2014, 16:57
Re TM's post with the following para. courtesy of Airbus:

"This type of engine compressor stall (« Popping ») is a known transient phenomena on turbine helicopters. It is characterized by a noise which can be followed by transient vibrations. In itself, such “popping” does not represent any direct risk to subsequent continuation of the flight.
An information Notice on compressor stall describing the phenomena and both operational and maintenance recommendations is currently being prepared and will be issued over the next days."

Maybe the translation from the original French conveys the wrong impression when reading these words? The implications are more than interesting, anyway.

During the fly-off between the SA and the Boeing UTTAS aircraft, one had a consistent stall problem at one point ( Boeing ) and one did not ( SA ). GE issued a memo to Boeing containing a criteria for their stalls. Depending on the power and alt/temp conditions, each stall event earned so many points. Eleven points and the engine came out. Boeing made a mod to their inlet eventually and the problem went away. Reason we ( SA ) knew about it was that the Army made us duplicate all of the precise BA stall conditions ( got the impression that Boeing initially proposed that it was an engine problem, not an aircraft interface issue ).

The trouble with generalizing with compressor stalls is that they can be a nuisance occurrence or a major #*&$ issue. Some decades ago I had one of the latter in a B model UH-1 at an inopportune time/section of the flight envelope in a warm environment that certainly required immediate reaction, so I am inclined to wait for details to see how this story turns out.

HeliComparator
20th Dec 2014, 18:03
It's a good idea to blame the pilots when you have virtually no facts. Saves the bother of actually understanding what happened. I am glad to see HC has learned nothing in the last decade.

In your haste for a chase you misconstrue me. My point was regarding the between-the-lines content of the AH article. It was in no way my personal appraisal of the situation.

Boudreaux Bob
20th Dec 2014, 18:33
In itself, such “popping” does not represent any direct risk to subsequent continuation of the flight.


OH....Now I wonder how they arrived at that decision and in just what context they mean for it to be considered?

An information Notice on compressor stall describing the phenomena and both operational and maintenance recommendations is currently being prepared and will be issued over the next days.

Further analysis of the available data will be ongoing and Airbus Helicopters will keep you informed as relevant information emerges from the investigation.


If HC is right, that Crew Members flying the 225 do not understand the "Beast" they are flying....is that due to Air Bus not having provided sufficient Data and Suggested Procedures in the past?

If I remember correctly, HC has taken the position in the past that it was the Operators who knew best how to operate the Aircraft and that Manufacturers knew far less in that regard.

Am I wrong in my recollection of your positions in other discussions HC?

Also, do tell us about the "Between the Lines" information.....that which is not visible to anyone but you somehow?

HeliComparator
20th Dec 2014, 19:38
OH....Now I wonder how they arrived at that decision and in just what context they mean for it to be considered?

Well that was my point, the context seems obvious.

If HC is right, that Crew Members flying the 225 do not understand the "Beast" they are flying....is that due to Air Bus not having provided sufficient Data and Suggested Procedures in the past?


Probably, hence they feel the need to provide an info letter now (obviously).

If I remember correctly, HC has taken the position in the past that it was the Operators who knew best how to operate the Aircraft and that Manufacturers knew far less in that regard.


Yes, in the case of the major operators. But no, one could not maintain that every operator, regardless of their experience and culture, knows how to operate the aircraft better than the manufacturer.

Am I wrong in my recollection of your positions in other discussions HC?


Selective recollection.

Also, do tell us about the "Between the Lines" information.....that which is not visible to anyone but you somehow?


I am impressed that you speak for the rest of the earth's population. Did you get elected world president or something when I wasn't looking? If not, maybe you could enlighten us as to how you know the above statement to be true? Or did you just make it up? Sorry but if you really can't understand and see my point, you are too much of a dullard for me to waste my time on. But of course I know you can, you are just stirring.

Geoffersincornwall
20th Dec 2014, 19:41
This is just the kind of malfunction that can be rehearsed in the sim. Forewarned is forearmed is not a bad philosophy.

G.

Variable Load
20th Dec 2014, 20:07
This is just the kind of malfunction that can be rehearsed in the sim.

Agreed, but only if the sim has been 'programmed' to accurately replicate the malfunction.

Do any of the EC225 sims have a 'pop stall' malfunction?

HeliComparator
20th Dec 2014, 20:54
We did put a "pop stall" function into ours, but it was only related to bleed valve malfunction. In UK we don't get pop stalls normally, and since training time is a limited resource, it is best spent on feasible scenarios. Anyway, most folk are aware of the possibility of pop stalls when landing on the Ninian, but it was more prevelant on the AS 332L and so is ingrained in 30+ years of experience.

Ultimately I don't believe you can train robotically and unthinkingly for every possible scenario. What you can do is train for a set of tools to be used intelligently when the unexpected or never-before-encountered situation is encountered. I think the buzzphrase is training for resilience.

rotorfossil
21st Dec 2014, 08:06
Spoke yesterday with someone (not a helicopter pilot) who was on the rig at the time. He commented on the unusually flat approach that was being flown. Sounds rather non standard to me and not giving much margin for error.

cyclic
21st Dec 2014, 12:24
but it was more prevelant on the AS 332L and so is ingrained in 30+ years of experience

'tis true, unfortunately a lot of that experience has gone and things that were taken for granted are now new to a lot of crews. The L2 is particularly prone to surging if the bleed valve offset isn't engaged at low power and, during acceleration if you are a little over exuberant with the speed select. We have two reports of a 225 "popping" in many thousands of hours of operation so not a common occurrence.

Hedski
21st Dec 2014, 13:41
Sounds like over reaction. Another incident in Brazil, where foreigners cannot fly....:ugh:

voando
21st Dec 2014, 14:43
You imply there are no incidents with Ec225 where you fly then, with or without foreigners? :=

Hedski
21st Dec 2014, 20:15
Not at all, I imply by reading the previous reports of damaged oil and gas helicopters in Brazil (225, 92, 76) operated by companies owned by large multinational operators who still will not allow foreign pilots work there that accidents are not due to type but to those at the controls who will not accept criticism and think they know better. :=:=:=:=

voando
22nd Dec 2014, 07:03
There are foreigners flying in Brazil - they either knew or learnt the language as required for the operations offshore - these are not international flights therefore not a need for English speaking according to stated ICAO diferences for Brazil. You can do the same, same as we have to get a license from EASA. Then you can use your evident CRM and knowledge to teach without doubt. :rolleyes:

CopterDoctor
13th Jan 2015, 18:14
RE-Hedski's post

Having talked to a lot of people who have worked or are still working there, that is the case,

voando
14th Jan 2015, 06:43
CopterDoctor .... I hope your sources are a little more convincing than rotorfossil's man on the rig who saw the non-standard shallow approach ..... when the incident occured on take-off!!

helihub
14th Jan 2015, 21:20
The "Helibras" mention may be an abberation for CHC subsidiary "Brazilian Helicopter Services" (http://www.bhs-helicopteros.com.br/) which is normally shortened to BHS.

jp4toulon
17th Jan 2015, 07:25
I totally agrée about the 332L2 stalling quicly when offset bleed not engaged at low speed (landing)
About 225, that occurs very often in Africa.
Due to a bad turbulence coming from the different profile of Main Blades
Proof of that : The scoop on engine cowlings at bleed exit was improved by add or a small redan. (At beginning of 225, several engine stall during taxiing with light tail wind and low wheigt
Information given by two friends , one test pilot at AH, the second tech rep at Turbomeca
Sorry for my poor englih writing :confused: