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Old 22nd Jul 2009, 06:19   #5461 (permalink)
 
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Caz


Quote:
In their evidence to the HOL Committee both the Reviewing Officers stated that negligence had occurred by the time the Pilots made the waypoint change. If they were IMC then the flight should have been conducted in accordance with IFR. If they were not in cloud then they had flouted the basic rules of Airmanship by flying too fast and too close towards the cloud covered high ground of the Mull which they subsequently impacted.





Is it not a reasonable assumption they intended to turn at or shortly after the WP? If a pilot intends to change direction at a waypoint which will take the aircraft away from cloud, it is not mandatory to transfer to IFR.

It is my understanding that, if at any point the Chinook had a latent control jam preventing the helicopter from turning, but the helicopter were continuing on a straight course (i.e. Aldergrove to WP A) the aircrew may not have had any indication that there was a problem. The problem would only become apparent when they tried to instigate a change of course away from dead ahead.


I’m no pilot, but does the above not completely negate the basis upon which the ROs made their decision? Especially given the plethora of evidence available about control jams, their cause (and sometimes unknown cause) and effect?


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Old 22nd Jul 2009, 07:36   #5462 (permalink)
 
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Chugalug 2

There is a known time for them leaving the Aldergove CTZ and a known time for impact. The average groundspeed between those 2 points was 158 kts and groundspeed at impact, whilst attempting an escape manouvre, was conspicuously similar at approx 150 kts(AAIB).

The Yachtsman could see that the Mull was shrouded in cloud and the Chinook passed approx 200 ft above him. It flew straight on, without deviation, until the final desperate attempted escape manouvre.

They were in control of the Aircraft at Waypoint change and they were in control for that final attempted manouvre. There was no evidence of any technical malfunction that could have caused the crash.

What you have to do is come up with evidence - not hypothesis - that proves the existence of a major systems failure so serious that it prevented the Pilots from transmitting a Distress Call, Squawking Emergency, activating a Distress Beacon or even getting their Pax to adopt Crash Positions. You would also have to explain how such a malfunction managed to disappear without trace and how it is that there has been no repetition of such a malfunction in the 15 years since this tragedy.

I would point out that no such evidence has yet been produced.
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Old 22nd Jul 2009, 07:58   #5463 (permalink)
 
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So Cazatou,

Where is your evidence to prove that they were in control at waypoint change and during the final attempted manouevre?
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Old 22nd Jul 2009, 08:30   #5464 (permalink)
 
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Caz, is it not true that the average groundspeed that you quote has been challenged? Was not the boundary time that of a radio call reporting clear of the CTZ rather than exactly crossing it? Was the time of impact from the same time base? I cannot see how as the first must have been an ATC one, the second from the aircraft data base. Whatever the average groundspeed overall, how does this reflect your "flying too fast" speed which is presumably based on IAS and reflects GASO Helicopter Low Level VFR speed restrictions. Is that so and if so what is that max IAS? Is it not also true that the "150 kts" impact speed was not deduced from impact damage by the AAIB, as I thought, but by Boeing's infamous model and your supposed escape manoeuvre inferred by the position of cyclic, yaw and thrust controls. Could these same indications have been rather signs of vain attempts to regain control, together of course with the detached collective spring balance found in the wreckage? Contrary to what you say Mr Cable stated that the possibility of a control system jam could not be dismissed. If that had happened I cannot think of anything more major, with both pilots solely and desperately concerned with regaining control of the aircraft to the very end.
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Old 22nd Jul 2009, 09:24   #5465 (permalink)
 
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1.3

Caz will trot out the following mantra, as he did when answering, on JP's behalf, an even simpler request for evidence (see Posts 5304 and 5342).

Quote:
It is not the case that JP (myself or anyone else) has to produce new evidence to "PROVE" that the finding of the BOI was correct. If, in UK, a criminal case goes to the Court Of Appeal; the Prosecution does not have to produce new evidence to maintain the Guilty verdict. It is up to the Appellant (and that persons Advocates) to produce new evidence that justifies overturning the original verdict in the eyes of the court. The same applies in Civil cases.
As far as he is concerned, despite IMHO the BoI being flawed, he does not have to prove anything to anybody. Wratten and Days verdict, in his opinion, was correct and proper and therefore until someones finds some new evidence that is positively, undeniably and "without any doubt whatsoever" contrary to Wratten and Days opinion he will not change his position.

Shame Wratten and Day didn't apply the same policy, particularly with regrads to evidence.
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Old 22nd Jul 2009, 10:02   #5466 (permalink)
 
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In any case, Caz is not a legal expert, as is evidenced by his mantra.

The defence in an appeal merely has the prove that there was a procedural error in the original prosecution to have either the 'guilty' verdict quashed, or a retrial ordered.

The fact that the ROs ignored the requirements of the AP as approved by the Air Board is sufficient.

The defence in this case can also point to the deliberate withholding of vital evidence known to the prosecution.

In a court of law this would have been overturned many years ago.
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Old 22nd Jul 2009, 11:57   #5467 (permalink)
 
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Wrathmonk, caz stated that even if a major emergency occurred after waypoint change the finding would still stand because they were "flying too fast". I am not asking him to defend the finding, I'm asking him what "flying too fast" means specifically, and how he knows that they were "flying too fast". Of course if anyone else can answer those questions it would be instructive. The more one probes into this BoI the more it seems that the pilots were hung out to dry on the evidence "modelled" by the manufacturer. Given that there is a very good chance that the aircraft crashed because of known deficiencies in ALL Chinook Mk2's, that evidence is suspect even before one studies the reliability of the data on which it was "modelled". It is at that point that I find I have very little faith in it whatsoever. It would be interesting to see what view an objective and fair Accident Investigation would make of it. That has yet to happen.
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Old 22nd Jul 2009, 12:45   #5468 (permalink)
 
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Caz

See my #5499.

Any thoughts?

Thanks
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Old 22nd Jul 2009, 15:07   #5469 (permalink)
 
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Olive, thank you for the link to past posts on VFR, from which we get the MOD's version (to the Mull Group):
Quote:
"The Board members concluded that the prevailing weather conditions were such as to demand flight in accordance with Instrument Flight Rules (IFR) in the vicinity of the Mull of Kintyre. The prescribed minima for flying visually, VFR, are horizontal visibility of 1 km beneath a cloud base of at least 250 feet, if flying below 140 knots; and a visibility of greater than 5kms, 500ft minimum cloud base, and 1500 metres horizontally from cloud, if above this speed.
which you confessed yourself content with at #4576. Thus it would seem that "flying too fast" would imply an IAS in excess of 140kts. Messrs W&D were obviously of the opinion that was indeed the case, as they seemed to suggest to the HoL that conditions could well have been VMC before waypoint change as compared to "the vicinity of the Mull of Kintyre" requiring IFR as above. Other than the "modelling" by Boeing, why should there be reason to believe that IAS was indeed above 140kts? Other than suggesting that to gainsay the RO's findings is absurd, is it not true that as ever we just don't know what their precise IAS was?
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Old 22nd Jul 2009, 15:16   #5470 (permalink)
 
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Quote:
Originally Posted by Olive oil View Post
The Rules of The Air for an aircraft flying under Visual Flight Rules (VFR) are simple and brief:

1. Pilots are responsible for maintaining separation from other aircraft.

2. Pilots are to maintain visual meteorological conditions (VMC). If a pilot is unable to maintain VMC, instrument flight rules (IFR) are mandatory. The conditions for VFR vary according to aircraft type and speed and are stated earlier on this thread. (4560 region).

The ROs were both experienced and accomplished pilots in their respective rotary wing and fast jet fields, with clear understandings of the Rules of The Air when making their judgements. It is absurd to suggest that they made their decisions lightly or that they selected information to fit their findings.
Olive,

I would be genuinely grateful if you would cast your eyes over this missive in it's entirety as I would value your thoughts.

If the RO's had told us exactly what had happened, stated exactly why it had happened and furnished everyone with proof that satisfies the requirements to enable them to reach the verdict they had, then this thread and the campaign would have never have come to fruition.

I spent the best part of 10 happy years as a Puma crewman, initially when it was 2 crew ops, then operating in NI in some of the most awful weather day and night, then in Germany with trips to Belize etc. I hark back to those days and the healthy respect for weather that rotary crews were taught from day 1 and there are, amongst many others, 3 main things here, that for me simply do not add up.

1. Nobody can state with any degree of accuracy as to at what exact point the aircraft departed VFR and entered IFR. In fact whilst it's generally accepted, based on witness statements that at some point prior to impact they ended up being IFR at max chat, no one can prove conclusively that they were ever IFR.

Before people snort in derision I ask the aircrew amongst you to consider how many times you have been aloft and seen the edge of fog/low cloud where within 100 yards or so you could go from absolute porridge to gin clear? Or the drivers amongst you to consider how many times on a motorway have you gone from fog to clear in a few car lengths? Unless I have mis read things there was no witness at the point of impact so how can anyone say with 100% certainty the crash site was in fog?

2. Nobody can state with a 100% degree of certainty that the aircraft was serviceable prior to impact. I agree fully that no one can state the aircraft was definitely U/S but there is undeniable evidence to suggest a control malfunction could have occurred but was discounted.

3. Based on the assumptions made by the RO's nobody can tell me why an experienced 4 man crew would ever act in the manner required to confirm the verdict reached. Not a shred of what is assumed fits with SH SOP's and for the life of me I cannot understand why anyone would reach this conclusion.

I spent the first 14 years of my service life as an aircraft technician and whilst I would have loved to have been a pilot I was simply never clever enough so I applied for ALM. One of the main reason for my acceptance and subsequent success, as debriefed by many, was my ability to apply common sense and logic to situations which is all I have tried to do here.

Common sense and logic tell me the aircraft was almost certainly serviceable prior to impact and the crew quite probably porked up. What common sense and logic also go on to tell me is that probably etc simply does not support the verdict reached and tells me that for the life of me I don't know now and never will know exactly why this accident happened.

Now I have always admitted to not being the sharpest tool in the box and all I have ever asked of John Reid on the flight deck of Albert, JP, Caz, Baston, Atlantic Cowboy and others is to show me the conclusive evidence, the smoking gun if you like that give a 100% confirmation of the RO's findings.

Prove to me without a single shadow of a doubt at what point the aircraft went IFR and prove to me without a single shadow of a doubt that the aircraft was fully serviceable at the point of impact and you will convert me to your way of thinking.

But if all you have in your locker is the same supposition that I have this could go on for a while.
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Old 22nd Jul 2009, 16:50   #5471 (permalink)
 
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Apologies for an intrusion from a non-aircrew long-time lurker but may I suggest a slight amendment to SFFP's previous missive.

"Common sense and logic tell me the aircraft was almost certainly serviceable prior to impact and the crew quite probably porked up. What common sense and logic also go on to tell me is that probably {etc simply} does {not} support the verdict reached by the ROs, however it does not meet the rules in force at the time that "there should be no doubt whatsoever" as to the cause. "



Some have said recently that "no doubt whatsoever" is an impossible standard to achieve and they may well be right - but as this concerned aircrew not able to represent themselves, maybe that was the hidden intent of the standard. After all the rules for ascertaining blame were changed not long after this weren't they?

No matter though because whether or not it was impossible to meet the standard surely the ROs were not entitled to ignore it. The fact that they did use assumption and 'educated' guesswork to support their ruling is the reason this thread was started and is still going.

Back to watching.......
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Old 22nd Jul 2009, 18:26   #5472 (permalink)
 
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Unfortunately "no doubt whatsoever" requires no evidence to back it up. It is a belief. No proof is required.
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Old 22nd Jul 2009, 19:27   #5473 (permalink)
 
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It would seem that the Boeing simulation, the whole basis for the 158kts impact speed and for the "final flare" which W & D claimed showed that the aircraft was under control 4 secs before crashing is at best a red herring, at worst it brings the motives of those who produced it, offered it as evidence and used it to arrive at the "finding" into question. From the HoL Report:
Quote:
Detailed examination by the AAIB of the flight control system disclosed that the DASH extensions found did not correspond to a high speed level flight condition whereas the LCTA extensions did, and it appeared possible that the settings could reflect a dynamic aircraft manoeuvre at the point of impact. Boeing were therefore asked to undertake a study to assess the consistency of the settings and to define the possible manoeuvre. The simulation was a mathematical exercise which, as Mr Cable stated, was "looking really for fairly gross manoeuvres over a pretty short period of time" (Q 957). It was not intended to produce an accurate reconstruction of events but rather to demonstrate what could have happened within certain parameters (Q 982)....
123. The Boeing simulation considered a wide range of possible starting conditions, i.e. conditions pertaining immediately prior to a final manoeuvre. Having rejected possible conditions at an airspeed of 135 knots, they concluded that an airspeed of 150 knots (groundspeed 174 knots) with a ROC of 1000 feet per minute provided "a ready match" with the criteria and was therefore the most likely (AAIB statement para 8)....
The groundspeed of 158 knots at impact derived from the Boeing simulation exceeded by 11 knots that of 147 found in the cockpit ground speed indicator (AAIB statement para 6). Moreover, the postulated ROC of 1000 feet per minute at 150 knots airspeed is unattainable. Squadron Leader Burke doubted whether it was achievable with ZD 576's load (Q 920). Witness A explained that while flying he had tried to see whether Boeing's chosen ROC was obtainable at 150 knots and had found that it was impossible in similar conditions (QQ 813-23). He had achieved no more than 400 feet per minute at 150 knots.
There is much more of the same at
House of Lords - Chinook ZD 576 - Report
but I would be getting my collar felt for adverse effects on PPRuNe Bandwidth. The HoL Report demolishes W & D's, the RAF's and the MOD's case. Trouble is of course they just don't admit it. Someone somewhere has to bring them to account. This was a scandal 15 years ago and remains so today. This aircraft was unairworthy and most probably crashed for that very reason. Time that was faced up to.
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Old 22nd Jul 2009, 19:28   #5474 (permalink)
 
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S&S, good to see you around again. You are, of course, correct.
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Old 22nd Jul 2009, 20:16   #5475 (permalink)
 
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Chugalug,

Perhaps you can tell me who made the input to flare the aircraft 4 seconds before impact if it wasn't the pilots.

AC
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Old 22nd Jul 2009, 20:22   #5476 (permalink)
 
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"no doubt whatsoever" implies to the general public and to (legal minded politicians) that there's nothing to see here, move on, no foul play, no undisclosed exercise, nothing other than bad airmanship/ pilot error, ignore the conspiracy theorists, no need for more thorough investigation, aircraft and its kit were fine, etc, etc.
Wrt SFFP's (rather excellent, I concede) post, this bit sums up the thoughts of many:
<<3. Based on the assumptions made by the RO's nobody can tell me why an experienced 4 man crew would ever act in the manner required to confirm the verdict reached. Not a shred of what is assumed fits with SH SOP's and for the life of me I cannot understand why anyone would reach this conclusion. >>
I agree totally – simplistically blaming the crew does not sit right – at all.
But if the desired impression is as the first paragraph above then, working backwards, a verdict of gross negligence is required to get it.
So:
1 why was this result so important?; and
2 why is it still necessary to maintain it?


I suggest that while dispelling doubts on the airworthiness of the (then) new HC2s could have been a reason for (1), with their subsequent successful record (2) should not apply.
If it had been a case of an exercise gone wrong, (1) may have been expedient at the time but, with the determination of this campaign, surely the MOD would have yielded, sharing the blame and reducing the judgment against the pilots? So (2) should no longer hold.
I subscribe to the theory that there could have been possible public unrest in NI if there had been any chance of foul play so at the time (1) held – had the peace process been universally accepted as a good thing and people had moved on (sort of the end justifying the means) then (2) wouldn't be explained – but the peace process is still not universally accepted as a good thing 15 years on so (2) holds – and one would hope that just clearing the pilots' names would never be enough, that accepting the crash we had to have for the peace process would be OK if only some of your own service didn't have to carry the can would never be right.
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Old 22nd Jul 2009, 21:35   #5477 (permalink)
 
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A total amateur dipping his toes in.

Could someone explain, in simple language, why two highly qualified pilots (in their SH/SF role) would voluntarily fly into a hillside?

Were they both suicidal? Were they both confused? Or were they both convinced of their actions?
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Old 22nd Jul 2009, 21:58   #5478 (permalink)
 
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Atlantic Cowboy:
Quote:
Chugalug,
Perhaps you can tell me who made the input to flare the aircraft 4 seconds before impact if it wasn't the pilots.
Well that's the whole point AC, there was no flare because the aircraft was not under control, hence the unusual combination of power and flight controls and other evidence of flying control abnormalities found in the wreckage and all tidily ascribed to impact effect. Read about it at the HoL Report Link in my previous post. Only don't let anyone catch you doing it, they might doubt your commitment to "Command Integrity" (nice Humphrey-ism that, don't you think?):
Quote:
128. The Boeing simulation postulations of a ROC of 1000 feet per minute and a speed of 150 knots were essential to the conclusion that a final flare was initiated some 4 seconds before impact. Now that those postulations have been shown to be unattainable, the circumstances and indeed existence of any such flare must be very doubtful. That there was such a flare was crucial to the Air Marshals' conclusion that the crew must have been in control of the aircraft for the last 4 seconds before impact (e.g. QQ 280, 1088). Sir John's calculations (above) give no support to such a conclusion, since they are independent of and in no sense a substitute for Boeing's postulations.
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Old 22nd Jul 2009, 23:13   #5479 (permalink)
 
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Quote:
Originally Posted by Olive oil View Post
Thank you for your post 5509. I am away for a few days with no access to PRuNe but I will reply in due course.
Enjoy your trip, I hope it's somewhere with better weather than we have here
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Old 23rd Jul 2009, 06:51   #5480 (permalink)
 
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AC


This has probably been posted before, and I’m sure you considered this, or similar events, when briefing Ministers that you knew exactly what occurred in ZD576, but to my non-pilot eyes this is bloody frightening.

The issues that stand out (to me) are highlighted toward the end. Notably, “complex”, “confusing”, “limited guidance” and, probably quite significantly, 2000’ AGL at the beginning of an incident that lasted 20 mins.

I also note the incident took place over 5 years after Mull, yet perfectly describes events reported by test pilots BEFORE Mull (but which were withheld from the BoI) and were STILL considered a safety hazard. One assumes in those 5 years the Mk2 had progressed from a development aircraft to one of acceptable design maturity (which it certainly wasn’t in June 1994) and the crew had the benefit of an acceptable number of hours experience (as opposed to a quick conversion course, followed by some months back in the Mk1, then having an immature and sub-airworthy Mk2 foisted on them a few days before the final flight).




AIR INCIDENT ODI/381/99 CREW REPORT

Chinook Mk2 ZD98l - 18 Squadron. RAF Odiham

5th October 1999, 15l0Z VMC I20kts, +6 deg C, 2000ft AGL

ZD981 was the Lead a/c of a 2 ship formation transiting from Shawbury to Odiham. Approx 10 mins after departing Shawbury, a small jolt was felt throughout the airframe and the capt'n in the RHS noticed that some of his fit instrument power flags briefly showed and the Master Caution Panel (MCP) lights flashed on and then off. A check of cockpit indications was made but all appeared normal.

Approx 2 mins later, similar symptoms were noted again without any subsequent indications of a problem. The jolts were very similar to that felt when the AFCS (Automatic Flight Control System) extendable links centre after a power interrupt and the conversation amongst the crew concentrated on this possibility.

Approx l min later, a series of jolts and power interrupts was experienced and the Captain elected to switch the AFCS off to prevent the a/c jolting.

Approx 2 sees later, the Master Cautions and all the captions on the CAP illuminated dimly. ALL power was lost to the primary flight instruments, including the main Al (Attitude Indicator) and the HSI (Horizontal Situation Indicator), and to the engine instruments. The only services remaining were those powered by the essential battery busbar. A loud hum was also heard through the intercom system which pulsed in phase with the captions of the CAP.

A check round the cockpit was made and all the CBs were checked and confirmed to be OK. The forward LCT (Longitudinal cyclic trim) was seen to be in the fully retracted position so speed was reduced to approx 80kts (Vmax with LCT retracted) as a precaution. The aft LCT indicated just below the ground position.

The Captain ordered all non essential equipment to be switched off and the formation was turned hack towards Shawbury - the nearest Military airfield. A practice Pan was in progress on guard so the formation changed frequency to Shawbury Approach and a PAN was declared.

CB's were checked once more and the crewman checked the TRU vents (Transformer Rectifier Unit) and the external bays for any evidence of a malfunction, but nothing untoward was seen.

The co-pilot attempted to find a relevant page in the FRC (Flight Reference Card) to assist with the diagnosis but none of the cards fitted the indications. The Captain had recently discussed electrical problems with the Brintel Simulator Staff and recalled a similar scenario where isolating the AC and DC cross-ties enabled one of the two electrical systems to be brought back on line. The co-pilot was ordered to trip the No 1 PDP (Power Distribution Panel) DC and AC cross-lies, but this had no effect and the CB was re-set.

The Captain then tripped the No.2 PDP DC then AC cross-ties. Tripping the AC cross-lie resulted in restoration of services from the No PDP. All the Captains flight instruments returned to normal as did the No2 ECU indications but all the services powered by the No.l PDP were still inoperative. The CAP partially cleared with the following captions remaining:

(a) L FUEL PRESS
(b) RECT 1
(c) AFCS 1&2
(d) XMSN OIL PRESS & XMSN AUX OIL PRESS

A check round the cockpit was done and the LCT indications were noted to be in the same positions as before.

With partial electrical power restored and the a/c in a safe configuration heading towards Shawbury, control was given to the co-pilot to enable the Captain to consult the FRC.

A scan of XMSN temps and pressures showed all to be normal, so the XMSN oil and AUX oil captions were dismissed as spurious. However the jump seat occupant wsa ordered to monitor the indications.

CAP indications were now similar to a single TRU failure with no cross-tie and Card 31 was used as reference. The Captain decided not to re-set his cross-tie CB having diagnosed a Bus-Tie fault of some kind.

The cross feed was selected open to start balancing fuel but with no success. The crewman operated the XFEED valves manually which cleared the L Pressure caption and Illuminated the XFEED caption.

An attempt was then made to program the forward and aft LCT in manual with no success indicated.

On short finals to land, the LCT were selected to retract for 30 secs IAW FRC35. At this point No2 a/c of the formation informed the Lead a/c that his aft wheels had swivelled through approx 45 degrees. The captain took control and made a vertical Landing followed by a gentle taxi forward to straighten the aft wheels. As weight was placed on the aft wheels a small power spike was seen on the Captains HIS power flag.

As the LCT were in an intermediate position it was decided to clear all the passengers from the a/c prior to shutdown. A visual inspection of the front and rear rotor disc attitudes appeared normal so the Captain elected to conduct a normal shutdown but with No2 PDP AC and DC cross-ties left tripped.

APU start was normal. The No.l generator was selected OFF with no change to indications. As No.2 generator was switched OFF thereby allowing the APU to come on line, all electrical services and indications returned to normal. The LCT were selected to AUTO and the fwd and aft LCTs were seen to trim to the GND position.

As a precaution against possible power spike induced FADEC faults, the ECL (engine condition lever) were selected to 55 degrees prior in ECU (electrical control unit) shutdown and the following codes were noted.

No1 DECU A7, Al, DB
No2 DECU 88

A normal shutdown was then completed with normal response from FADEC. Post shutdown it was noted that the avionics cooler fan had tripped.

This entire incident lasted 20 minutes. Indications were complex and confusing and initially the FRC were of limited guidance. In the end Cards 31, 32, 33 & 35 were consulted. It should he noted that the Brintel simulator training proved invaluable in producing a quick albeit partial solution to the loss of electrical power.

The fault was considered to be a major safety hazard, and had the crew been less experienced or in IMC or at night the outcome might have been considerably different!
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