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-   -   Airtours C404 crash report (https://www.pprune.org/tech-log/10203-airtours-c404-crash-report.html)

411A 4th Aug 2001 08:13

Kiltie---
I would also not agree that these aircraft are not suitable for charter operations. They have proven over the years to be very reliable however, at MTOW they have very limited performance with an engine inop. The 404 has a large cabin with 11 seats but it is not always a good idea to fill them all. On the other hand, this same fuselage, when pressurised and fitted with Garret engines becomes a CE441, and this type DOES have good performance. My favorite machine, bar none.
With regard to run-up while taxiing, an incident I personally saw last week in which a CE414 tried this and ended up in the dirt with the left gear collapsed shows that it is, at best, ill advised. :eek:

gaunty 4th Aug 2001 14:42

Listen to the wise words of pterodactyl, you do not get to be as old and wise as a pterodactyl without knowing a thing or two.

411A you may be surprised to learn that notwithstanding that I wholeheartedly agree with you about the C441 being an outstanding aircraft, it's actual EFATO performance at gross weights isn't all that much better if at all, than the C404, neither is it required to be. "measurably positve" is the go. It's the old FAR23 certification issue. There are no legal EFATO figures (beyond accelerate/stop/go distances 50 ft obstacle) for FAR 25 type climb gradient other than for Engine inop ROC. If you take the time it is possible to construct a defacto FAR25, 1 thru 4 climb segment obstacle clearance scenario, but it is not provided.
Like the C404 or any FAR 23 twin including the B200/MU2/Cheyenne. blah blah, especially the big MU2s and don't get me started on those, in the EFATO scenario you are just hanging out there damned if you do and damned if you don't.

Kiltie 4th Aug 2001 14:54

Little to compare between Titans / Chancellors / Golden Eagles with Conquests or Caravans - gas turbine power will always vastly improve performance when matched to the same fuselage. Having flown turbine 400s alongside their piston variants I agree I'd rather be in a Conquest or whatever but the cost of purchase / operation of a PT6 or Garret powered machine over a TSIO-540 is prohibitive for most (UK at least) small charter operators, so I still think the 404 / 402 etc. has a role; but as you say at max AUW performance rarely matches that of the handbook when the aircraft is 20 years old.

Where do you stop at banning piston powered light twin charters? Do we keep Aztecs, Senecas, Barons & 310s etc.? Or would you say these were potential disasters as well?

PS when I was discussing taxiing run-ups I really meant a 30 sec stop at the holding point rather than continuing with forward motion; but not to the extent where long noisy power checks need to be endured.

Hudson 4th Aug 2001 14:54

Kiltie.

I tend to differ with your opinion. I doubt if there can be any valid operational excuse for run-ups on the run, or a quickie feather check and quickie mag check at the hold. It is short cuts that kill people. If the ccompany cannot afford the time and money to operate the aircraft as per manufacturer's recommendations (and that includes a proper engine check as per POH) then they should not be in business.

Believe me, the short cuts which you state that there is nothing wrong with, would see you crucified in a court of inquiry and worse still in a court of law - if they resulted in an accident.

Quote from your post:
Personally I see no fault with run-ups "on the move", so long as the full engine checks were performed on the first flight of the day. I don't know if this aircraft had flown previous to that of the accident flight on the same day, but if I was carrying passengers I would be inclined to abbreviate the run ups to a simple mag check and quick feather excercising at the holding point without undue "revving". This is commonplace in the charter environment and not inherently an unsafe corner-cutting measure.
Unquote.

I hope for your sake that you never have a prang where your words could come back to haunt you. No offence met, old chap - and I really mean that. But so many accidents have been caused by short cuts rationalised in the name of legitimate cost savings.

"This is commonplace in the charter environment" is a clear indictment of the GA industry.

[ 04 August 2001: Message edited by: Hudson ]

Area Juliet 4th Aug 2001 22:07

Regarding the run up/power checks required in the 404 for those of you who aren't aware of them:

engine gauges …………………………….. normal
both throttles …………………………….. 1500 RPM
magnetos …………………………….. check (max drop 100RPM, max difference
50RPM)
*propellors …………………………….. check feather
*mixture lever operation …..………………….… check
*pneumatic de-ice system ……………………… check (if required)
hydraulic flow lights …………………………….. check
engine gauges …………………………….. check
throttles …………………………….. *close/check idle, reset 1000 RPM

Hmmmmm........not exactly an awful lot to do.

Just two points for thought.

1.If done stationary (which is always going to be the best option) then the amount of time taken to complete this procedure is hardly going to have any significant implications on the duration of the flight, so to accuse the pilot (even if he did own the company) of cutting corners for financial reasons seems a bit extreme! We're not talking about a PPL who can't remember where the levers and guages are or where he is in the checklist!

2.As stated previously 'not exactly an awful lot to do'. Therefore if done on the move at a slow taxi speed it really should not be too much to cope with.

Area Juliet 4th Aug 2001 22:16

Sorry, forgot to add this bit.

The run up/power check issue to the thread therefore seems to me to be a bit of a tenuous sideline to the analysis of what went wrong with this flight.

Kiltie 4th Aug 2001 22:24

Area Juliet thanks for that breakdown; that proves that performing the actions quickly does not necessarily mean they are corner-cutting or unsafe. Familiarity with type will always see such checks done expeditiously without "missing bits out" for want of a better phrase.

Area Juliet 4th Aug 2001 23:55

Exactly Kiltie, it's not exactly rocket science for those of us that fly the C404 regularly.

Puritan 5th Aug 2001 04:26

W.r.t. 'sudden chop of the throttle' type engine failures we've all had during training / testing.

Many (many, many) moons ago when I was doing my MultiEngine rating, and during a cruise phase of flight, my learned instructor reached down between the seats of our Seneca and (unbeknown to me) turned off one of the fuel taps.

My subsequent reactions to what happened next where almost laughable, as the fuel starved engine coughed, spluttered, and surged its way towards stopping. My inexperienced feet were doing a veritable tango on the rudder pedals (making it worse), i.e. with the aircraft yawing about all over the place, plus the engine gauges bouncing up and down like whores-draws (there was a clue there somewhere, duh), I didn't have any bloody idea as to which engine had failed - and this was made all the worse by my instructor (simulating) total panic at what was going on.

It took (what seemed) ages before I was positively able to identify which engine was having the problem.

Yep, I (very thankfully) learnt a serious lesson from that about the insideous engine failure case, and how important it is to properly identify just what is the real problem, i.e. don't rush the drill.

That said, being in the cruise, with the luxury of time (or even from an armchair, with a beer alongside :) ) it's all very obvious, but in a heavy aircraft on takeoff, and one with crap s/e performance.......... uhm ? no thanks !

411A 5th Aug 2001 05:27

gaunty---
Performance numbers for 404 & 441:

404: MTOW 8400lbs, engine out ROC: 230 ft/min.

441: MTOW 9850lbs, engine out ROC 715 ft/min.

As you can see, the 441 is just a tad better. Cessna figures, not mine.

'Course, you need at least $1.5 million to slide into a 441 in decent shape.

pterodactyl 5th Aug 2001 07:36

Puritan
Don't know about the Seneca but it is quite possible in cruise flight depending on the airspeed in the case you mentioned for
the RPM to windmill at governed RPM and if the throttle has not been moved from cruise setting the manifold pressure would be the same as before. So you have both engine parameters of RPM and Manifold pressure the same. This would occur as long as the airspeed was high enough for the prop to reach governed RPM before it reached full fine blade angle. In due course as speed decayed as a result of the windmill drag RPM would reduce when full fine blade angle is reached. A good thing to be aware of don't you think?
At take off with lower airspeed windmill force would not be enough to do this in the case of a total failure. In any case Dead foot, dead engine is the PRIMARY way to identify the problem using other indicators only as a confirmation if appropriate.
Can't say that running a fuel tank dry or the like is good practice. :D

Puritan 5th Aug 2001 13:45

W.r.t. 'Can't say that running a fuel tank dry or the like is good practice ', to some extent I disagree and would have to ask "why not ?". E.g. in the above, all that was actually done was to close the fuel tap and allow the engine to suck out the fuel downstream of the tap; and perhaps I should have mentioned that at the time we were several thousand feet over the sea and within site of the home airport - i.e. there's also a time and a place.

I accordingly then learnt a whole stack about how the engine actually behaves when it is starved of fuel, i.e. it doesn't, and contrary to many folks impression, just stop-dead. It surges, and that in turn causes the aircraft to yaw from one side to the other, making it harder to identify just which has failed. Plus, and as you say the wind-milling prop causes manifold pressure and RPM to remain pretty much static; Of course in this instance fuel flow was the clue - but with only 100 TT, and 6 on the aeroplane, plus way too confident, hot shot here learnt some very valuable lessons that day.

Similarly now, in the simulator with a V1 cut - it's very unlikely that the engine will actually stop dead in that manner (but that's the hoop that the authorities wish us to jump through, so we do). However imho we should practise a lot more failures of the insidious kind, e.g. early on in the departure during a complex SID and / or with an engine-out emergency turn procedure (e.g. a Barkway departure off R05 at London Stansted, straight ahead on 046 degrees to 2DME then left turn inbound to BKY. During takeoff roll the bloke in back provides an intermittent PMC failure (you get some very small engine surges, nothing above N1 limit, and you put the yaw down to the 30Kt crosswind that he's also given you coming off the terminal). During the climb out the PMC intermittently fails a few more times, but again you put the subtle yaw and engine indications down to the turbulence and / or maybe the auto-throttle buggering about. Just as you commence the big left turn to BKY with the flaps coming up and the autopilot going in, your mate in the back gives you a full PMC failure plus a blocked fuel filter on #1. This causes it to start surging big time - and it is also at the same moment when he chucks in a couple of distracting TCAS alerts - yep, it all becomes quite entertaining - but you haven't had an engine failure, at least not according to the QRH), or how about the classic run-down failure during a descent with thrust levers closed - i.e. you barely notice you've had an engine failure, until you need the engines.

The problem with failures, and as mentioned in many a subsequent board of enquiry, is that they are not always as cut & dried as we'd like them to be or have seen / tried in either training or examinations, i.e. it's nearly always a sequence of insidious events that lead to the scene of an accident - so the more exposure one gets to these less than clear types of failures the safer one should become - which is why we do our stuff in the sim - now is there a sim for the C404 ?

Ultimately - Aviate, Navigate, and Communicate.

pterodactyl 5th Aug 2001 14:41

As you say, Puritan the engine surges and possibly backfires and it is not a kind thing to do to a piston engine if you don't have to. You had the answer.
A similar cycling can occur on an engine fitted with auto feather such as a Dart as the prop alternately coarsens and fines off during the process. No need to be spring loaded just gently and positively apply rudder when a definite effect is evident.

Mapshift 5th Aug 2001 16:18

In the first few confusing, but critical moments of an engine failure during take-off on any aircraft..engine instruments can be most confusing and contradictory...all propellor aircraft involved in public transport should be required to be equipped with autofeather systems..particularly piston twins, whose moderate performance se-climb capabilities are often negated by only small downdrafts, or delay in accomplishing the recall items ie: feathering the prop expeditiously...a C-441 is an unfair comparison to a C-404..a GTSIO 520 is no match for the TPE-331..

411A 5th Aug 2001 20:46

Would NOT advise to run a tank dry in an aircraft fitted with GTSIO- engines.
The result from the surging may well be a crankshaft counterweight chucked thru the case, NOT a happy thought.
Overhaul cost, 'round about $35,000 including a new case. No insurance coverage either as TCM have a service bulletin about this (and related) subjects. These engines have good reliability IF operated properly.
If improved performance is desired from the 404, GTSIO-520K engines can be fitted under STC. These provide 435hp at takeoff and were originally offered on the AeroCommander 685.


Also would definately agree about Dart engines, they are very reliable but traps are there for the unwary. RR engines are one fine piece of machinery.

[ 05 August 2001: Message edited by: 411A ]

Mister Geezer 6th Aug 2001 14:22

411A I have to admit that I am slightly annoyed that you seem to question the abilities of the crew members, without knowing very much about their background and their career history.

The commander on that flight was very well respected within the aviation community north of the UK border. You and others may think, If only he had done something else then the outcome would of been different. Yes true but I think that there are not many of us here that are really in a position to question his ability or his actions! He was very experienced and was even a CAA examiner. Yes everyone can make mistakes but I feel that there are many others out there that would of done the same thing on that day when taking into account the unique circumstances that are detailed in the report.

It was a tragic accident and one which I hope is never repeated.

However on a lighter note I laughed when someone brought the name Jim Ferguson up. The pseudo aviation journalist from the north east of the UK! His remarks are taken straight out of the recommendations of the report. :)

MG

[ 06 August 2001: Message edited by: Mister Geezer ]

Raw Data 6th Aug 2001 16:26

Well, it seems to me that you are all completely missing the point. It wasn't doing run-ups on the move that killed them, or even the handling of the engine failure. What killed them was the attempted return to the field, followed by a loss of control as the airspeed decayed through Vmca.

In other words, a simple airmanship failure: FLY THE AIRCRAFT first, at all times.

There is no doubt in my mind that, had the pilot (whom one assumes knew the performance of his aircraft intimately) elected to continue ahead and put the aircraft down when it became obvious he couldn't maintain height, they could all have survived. There is enough flat, grassy land around GLA for that. It was the attempt to return that got them.

Most pilots feel an initial sense of anger or shame when they realise they have just made a big error, and this can cloud judgement. Most of us would want to be able to get the aircraft back to the runway if at all possible, but often you just have to accept that the safest option is to put it down straght ahead (+/- 30degrees). To my mind, that acceptance of an impending forced landing (never mind the ensuing investigation/paperwork/financial consequence), is one of the hardest obstacles to a successful outcome.

I never knew the pilot concerned here (although I had met him once or twice), but I am sure he was a great guy and a good operator. However, the very least that we should accept is that he made some bad decisions (however understandable), and people died as a result. There are many, many lessons to be learnt here.

pterodactyl 6th Aug 2001 17:21

Raw Data.
Yes, sad as it is this kind of mistake has been made repeatedly going back many years especially in the DC3 era. The pity is that the lesson has still not been learned. Though from my reading of the report it seems likely that stall rather than VMCA was the final result and certainly turning would not have helped.
Nevertheless, regardless of the alleged experience of the pilot the fact remains that the wrong engine was shut down and control was not maintained. In similar cases where performance has been lacking and control has been maintained the results have been far less severe.
One other factor apart from correct identification, which I previously perhaps too subtly implied is that an engine which may be malfunctioning but delivering usable power should not be hastily shut down at a critical stage of flight.

gaunty 6th Aug 2001 17:32

Raw Data
Exactly right.

411A
The figures are correct but the excess on the C441 is NOT as a result of any EFATO certification requirement, rather the marketing/design SHP required to produce the target 290KTAS at FL330.
If I recall correctly though the actual climb gradient produced is not all that different.

Although having said all that I would rather be in a C441. I have operated both and the C500 series as personal transport, the C404/421C win hands down in operating economics v speed/range. It is dificult to separate the C441 from the C500 series in overall performance with the prize going to the C441 on sheer range (I've put up 1900nm FL330 +35kts and landed with 90 minutes, but the C441 wins hands down in economics v speed/range.
Overall IMHO Cessna could no longer justify continued production of the C441 as I suspect it was too close to the C500s performance without offering the FAR25 protection.
It was a B200 killer every day.

But that is beside the point, it is the FAR23 v 25 argument that I am on about.

411A 6th Aug 2001 23:52

gaunty--
Would certainly agree with your comments re: FAR 23 (CAR3) vs FAR 25 (CAR4b).
And indeed the the performance and range of the 441 is impressive. My business partner flew one from LAX to DCA nonstop and arrived 23 minutes ahead of a Lear 24 (fuel stop required) that had departed 5 minutes earlier.
The C421 is undoubtedly the most economical pressurised piston twin available for executive travel, but some companies just "must" have a turbine.....until they get the maintenance bills. I have decided that our company will purchase a C441 iso a Lockheed JetStar as LAX-HNL is now not a requirement for us. The financial folks have been told rather bluntly that J/C on UAL is what they'll get, like it or not.


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