Short and concise, however it seems they had VS and LOC engaged but not IAS - so pilots were controlling airspeed via the collective. The autopilot would be controlling VS on the cyclic. But with insufficient collective the airspeed decayed until very slow, high ROD built up. I have seen confusion in the Sim when partial automation is being used - which control controls what. I wonder if the pilot was briefly confused about how to increase airspeed - lowering the nose of course is not the right thing to do.

I also wonder what, if any, the SOP for automation use is in CHC for a NPA, ie whether not coupling the collective is normal. I foresee a push to increase standarisation of use of automation after this.

A fine body of work that has taken a week to produce, have they got 1 person at the AAIB that shares his time between investigating, answering the telephones and doing a bit of cleaning?

Ah Pitts, I wonder if you are as perfect in your job (whatever it is) as you expect everyone and everything else to be?

The download was only commenced on evening of 1st Sept, its only lunchtime on the 5th, that gives 3 days for analysis and write-up, and today to publish. That's pretty good I'd say, considering the sensitivities and need to be absolutely sure of your ground before going into print.

If you ever get a real job in aviation, you'd better hope we don't find out who you are otherwise your life is going to be really miserable!

In my experience as a police officer less than half of reported crime has any realistic leads to follow. It's another number plucked and manipulated to make it seem like somebody isn't doing what they're paid for.

Turn up at burglary-view POE/disturbed areas-call CSI if appropriate-take statement- do house to house-give advice-arrange for boarding up/locksmith etc.-ensure support is there (SNT/family etc.) - record crime & submit. Await results from CSI/house to house/local intel etc. If none then no further investigation. What is there to investigate?

What they mean is there is no investigation past initial enquiries, because those enquiries have exhausted all reasonable lines in the first instance. We can't invent evidence or magic it up (some people's opinions notwithstanding!).

And now, back to your regularly scheduled AS332/EC225 pondering.

I guess you missed the bit about taking 48 hours to be rinsed and dried? :ugh:

I cannot imagine why you would not fly 3-axis in this situation (unless there was a collective trim failure) or would use V/S rather than ALT (or ALTA.)

HC, if you were using V/S only, recognised the low IAS and tried to correct by beeping forward, would it increase the rate of descent in the L2 by moving the V/S datum? I know the 225/155 etc wouldn't, but I don't know about the L2

Is this paper pertinent reading
 

Don't you think Pitts that it is much more likely that they know a great deal more than what appears on these two pages but not all of the pieces fit together properly yet, and unlike us, they are not running a rumour network.

But presumably, since you didn't comment on it, you are quite happy for police time to be taken up with putting sensationalist and trivial news on their facebook page, and infringing some else's privacy in so doing?

Of course 100% of reported crime can't be investigated, but less than 50% seems very low to me.

HC I don't think you need worry vis finding me doing a "real" job and not in aviation, although why you'd want to make my life a misery for expressing opinion on a forum probably says more about you than it does me.

In the meantime my comments are based upon the fact that its Sept 5th and actually aside from the publication of some basic data the remainder of the report is a typing exercise of basic information that was available from the first hours?? Or do I read it wrong??

I wouldn't want to make your life a misery, it would just happen naturally to one who is so quick to criticize others (even when there is nothing to criticize).

I'm guessing you have never had to interpret FDR data. Well I have and I can tell you its not as easy as it might seem to an outsider. First of all there are the technical issues of getting the right hardware to read the recorder, then the correct software has to be located, along with the correct data frame layout and conversion to engineering units. This may depend on the mod state of the DFDAU in that particular aircraft.

Then one has to allow for the inevitable data errors that can occur and be really, really careful to not jump to the wrong conclusion which I can tell you, is really easy to do. Yes, you can get the gist of it fairly quickly but with probably over 100 parameters to look at, and an unfamiliarity with that particular aircraft's systems and naming conventions, you have to go carefully and methodically. You would be a prize prune if you put something out in writing that turned out to be a mis-interpretation.

My posts say something about me, but you can be sure that your posts say a lot about you!

Hey come on. So you cool with the detail given the time?? I suppose the industry has the system it deserves.

Yes, after 3 days I wouldn't possibly expect any more. They have said what happened in detail, but it takes time to work out why (since at first glance I suspect it defies logic).

I don't know if the AAIB is what the industry deserves but as a professional pilot it is the system I want. They are careful, considered and dispassionate, and I have never heard any of my colleagues criticise them.

Earlier in the thread VRS was not ruled in/out until we had some figures available, does this now mean some of the more experienced might comment further on this possibility if indeed it is one?

Of course not, the upper echelons of the police service are staffed with just as many idiots as anywhere else, all greasy pole climbing back stabbing self interested book smart street stupid arses looking to their next promotion board. Some inspector or chief inspector will have decided that this will look good in their PDP and so had it written, probably with a layer or two of insulation should it go wrong and he needs someone to blame later on. All of which martially explains why I resigned last Christmas and am now back building helicopters and much happier for it!

Like I said, that 50% is a manipulated statistic. Due to poorly trained call takers who these days can generate a crime number with a mouse click, probably 20% of recorded crimes should never have been recorded in the first place, but are because of a lack of knowledge. They then get passed to a bobby to go on top of his teetering in tray, he takes one look and realises the error, but by now the crime has been generated. YOu get it reclassified as a no-crime, but even a no crime remains on the books as a no crime crime (if you get my drift!), it doesn't just go away. Very very few actual crimes will have no investigation whatsoever, most will have the bare minimum to establish that all leads have been followed and there's nothing else to do. But many people don't want to accept this basic truth.

I'm glad to be out of it!

Does this warrant discussion?
 

My posting a couple of pages back got trampled in a handbagging incident between Pitts and HC (Ladies, please!). Any thuoght on this as a theory?
http://flightsafety.org/hs/hs_may_june97.pdf

LOZZ - whenever a helicopter gets into an unrecoverable descent at low speed, theories of VRS are bandied about. However, this is often not correct, and certainly not needed to explain this sort of accident. There is a very steep increase in power required as the airspeed comes back around, and especially below translational lift speed. This is not due to anything to do with VRS but just a function of the rotors trying to scrabble to get lift in what has become a descending column of air.

VRS takes time to develop and you have to be at very low airspeed. I very much doubt that VRS developed before the heli hit the sea due to a high rate of descent resulting from insufficient power for the airspeed. And to be honest, whether it did or not is barely relevant.

I shall take a bit of a Contrarian view on this Special AAIB Report.

My view is this report should not have been released.

The AAIB should have waited until they had digested the CVR data and decided what it meant....then released a Special Report that would go much further in describing the sequence of events and the time line of the CVR.

The Report as it reads now...tells very little and only generates more conjecture than it would otherwise had they waited to put out the CVR information.

Far too little information to justify a Report at this time.

Don't forget that VS is a prerequisite for ALT.A on the L2. The AAIB doesn't mention ALT.A so we can't be sure whether or not it was engaged but anyway, I think the outcome would be unaffected either way.

Yes, on the L2 the mode on the cyclic is beeped on the cyclic, so if you had VS on the cyclic, when you beep forward you would in fact be increasing the datum rate of descent. This is something that was changed for the 225 (and from what you say, the 155) so that the vertical mode is always beeped on the collective, even if its engaged on the cyclic. Unfortunately I can't remember if the VS datum is recorded on the FDR. It is on the 225, but I suspect it isn't on the L2. Therefore the mentioned increase RoD near the end could be either as you suggest, or just the result of the autopilot being unable to contain the RoD at the very low airspeed and low collective setting.

OK, thank you HC.