If you used the checklist EVERY TIME then people would have NO cause to question it as a factor. The fact that some saw him use it and then some said not is very telling. If you use a combo of use and not use you'll come unstuck in no time.
|
Originally Posted by holdingagain
(Post 10256720)
Maybe x 2 the aircraft was refueled for a previous booking which was cancelled leaving a fuel excess for this flight he was mid way through his trim preflight check, answered his mobile and missed returning the trims to the take off possition |
Did you read anything on the report, holdingagain? It was refuelled right before the flight. Page 2, second paragraph, first sentence. TWT, if there was a checklist either a) it didn't have trims on it (that would be surprising) or b) he didn't use the checklist properly. mostlytossas, I agree that there were a few wild theories, but there were other good discussion points that many of us got involved in, whether or not they had, at the time, any potential contribution towards the accident. Do you not think that investigators come up with theories and investigate them whilst looking through evidence, even just to discount certain possibilities? |
Of course they do Ramrod . But they keep them to themselves while they work out if the cause or not. Unlike Pprune where some on here declare that the only cause can be so and so because this is what the evidence fits.
Then when they are shown to be wrong they look rather foolish don't you think? As the old saying goes....Better to keep your mouth shut and be thought a fool than open it and remove all doubt! |
Originally Posted by Mostly
Then when they are shown to be wrong they look rather foolish don't you think?
As the old saying goes....Better to keep your mouth shut and be thought a fool than open it and remove all doubt! |
As for checklists...I remember way back when most students learnt on C150's or Pipers the checklists were always done by ROTE memory. T..Trim, M..Mixture set F..Fuel, Flaps etc. Nothing wrong with this because the aircraft are simple and not a long list.
TRIM was always the first thing checked. As you move up to twins, turbines etc then written checklists are the norm. I read somewhere in the report either he or the company didn't use them? |
I read somewhere in the report either he or the company didn't use them? The PIC was cleared as competent to fly by a CASA FOI just months before (how many of us can say that?). He had over 2400 hours on type (how many of us can say that?). Primarily the speculation about checklists arises because an unrelated CASA audit of his AOC showed that the operations manual did not have a CASA approved checklist on the AOC holders format / logo. At the time of the accident he had submitted one which was subsequently approved. Not having a CASA endorsed checklist (as opposed from a Beech one or one from his previous AOC is completely different thing than not using one. But, still I ask, why wouldn't the aeroplane fly with full LH rudder trim? The ATSB flight sim excercised indicates that it should have. |
Wonder about the rudder force fidelity of the simulator used for this particular demonstration.
Why was this not done in an aircraft, using a qualified tp? How does left rudder trim and left yaw cause sideslip to the left? Makes me wonder if the author even knows the difference between yaw and sideslip. What else doesn't he/she know? |
Holdingagain has the most likely explanation, IMO. Distraction when working through a checklist (via mobile phone, Airways clearance, pax chatter, or?) could explain the full left rudder trim. It is not uncommon for distraction to create an accident.
SB. |
I can see how the rudder trim was left full deflection, wouldn’t be impossible to not complete and return to normal during the preflight internal inspections. That said, it’s inexcusable for this not to have been picked up during the before take off checks, or even down the runway prior to V1 (or similar, I only have experience on B350). It’s a pretty important item in the before take off checks. Not using a checklist in a complex twin turbine? Sounds pretty game. |
I can see how the rudder trim was left full deflection, wouldn’t be impossible to not complete and return to normal during the preflight internal inspections. That said, it’s inexcusable for this not to have been picked up during the before take off checks, or even down the runway prior to V1 (or similar, I only have experience on B350). It’s a pretty important item in the before take off checks. Has anyone noticed that the prelim report says that 10 deg flap was selected, yet the final report says zero degrees flap was selected. The report offers no explanation to reconcile this. It says that examination of the LEFT HAND motor shows the LH flap was retracted. The report says it is unable to identify the position of the RH flap. Wouldn't the LH flap being retracted and the RH flap being 10 deg down produce the same sort of effect? Might it cause the pilot to wind in full LH rudder trim to help compensate? |
This will now be a lawyers picnic.
|
Media has published happy snaps of the pilot in question in a Kingair cockpit.There is a rotary type checklist on the glare-shield.Be a mug if he didnt use it.
|
Originally Posted by Akro
Wouldn't the LH flap being retracted and the RH flap being 10 deg down produce the same sort of effect? Might it cause the pilot to wind in full LH rudder trim to help compensate?
|
I would think this would induce a roll to the left, requiring right aileron and probably right rudder and therefore right rudder trim. But the real question is a) how can the ATSB publish 2 reports with such a large discrepancy and laugh it off and b) why not investigate it in the SIM. |
Originally Posted by Old Akro
(Post 10256801)
For all we know, he did all the checklists perfectly & diligently. And the guy had 2400 hours on type. He wasn't a weekend warrior.
I do not know the accident pilot, so my comment here is in NO relation to him- it is a generic statement only: 1200hrs, 2400hrs, 24000hrs on type means nothing if you aren't actually a competent and diligent pilot. I remember inducting a new pilot to the company some time back. He had more B200 time than I had total (more than this accident pilot). He was the definition of complacent, he truly scared me. Said bloke had similar thoughts about checklists. |
I can’t believe that the pundits think the ATSB is infallible. They , ATSB, have got this wrong big time and it is a damn shame. Even with full left rudder trim she would have climbed like a homesick angel if both engines were producing full power. How do we know that the rudder trim didn’t get displaced by the impact forces? Groggy |
Originally Posted by Grogmonster
(Post 10256837)
I can’t believe that the pundits think the ATSB is infallible. They , ATSB, have got this wrong big time and it is a damn shame. Even with full left rudder trim she would have climbed like a homesick angel if both engines were producing full power. How do we know that the rudder trim didn’t get displaced by the impact forces? Groggy |
Groggy, read the report. Full explanation there as to how the rudder trim could not have been "displaced by impact forces" (e.g. the position of the jackscrew).
And, you will also read about simulator trials where the aircraft was taken off, with full NL rudder trim, and how difficult this was for the pilot to sustain. |
Said bloke had similar thoughts about checklists. And, I'm with Groggy. The issue in flashing lights is "why didn't it still climb?" Lets just say the pilot missed the rudder trim. The ATSB's own simulations show that at climb speed he would have directional control, The aircraft should have still climbed to an altitude which would let the pilot do some diagnostics and find the error. Why didn't it climb? Why didn't the ATSB investigate why it didn't climb? |
And, you will also read about simulator trials where the aircraft was taken off, with full NL rudder trim, and how difficult this was for the pilot to sustain. " The yaw on take-off was manageable......After takeoff the aircraft was manageable but challenging up to about 140 knots..." The aircraft didn't get above about 112 kt. So, on the ATSB's own evidence, the yaw from full LH rudder trim was manageable. |
I won't say that this report is the biggest load of cr@p I've ever read from the ATSB as practically everything they have written in the last 30 years or so is cr@p and the good old rubber stamp "Pilot Error" comes out again. They have obviously not consulted professional King Air pilots. I'm appalled once again.
|
Question from a pilot not rated on the King Air.
What is the scenario that the trim would be left in this position from a previous flight? |
Old Akro,
I don't believe you are reading the report as closely as you could, re the simulator trials. The pilot doing the trials said that leg muscle forces "could only be held for a short period of time". And obviously, the strength, fitness and age of the pilot would be a factor in exactly what the period of time was, and to which airspeed things could be managed. The simulator performance in this situation would not be an exact replication of the real aircraft. Did the simulation have the same CG as the accident aircraft? It doesn't say, but that aspect would have a bearing on the controllability. |
Originally Posted by FGD135
(Post 10256855)
Groggy, read the report. Full explanation there as to how the rudder trim could not have been "displaced by impact forces" (e.g. the position of the jackscrew).
And, you will also read about simulator trials where the aircraft was taken off, with full NL rudder trim, and how difficult this was for the pilot to sustain. With respect I take your point about the trim jack but please consider that if trim wasn’t checked then maybe the power lever friction nuts weren’t checked either. I could live with that scenario where both items were missed and Murphy took over with full left rudder trim and a rollback on left engine which would have resulted in a very very difficult situation. My reason is it should have climbed!!!! Groggy |
Somebody asked why, with both engines supplying full power, the aircraft couldn't still climb.
I believe the answer to this is because the drag was too great. With the pilot's "leg having given out", re the simulator trials, the aircraft's sideslip would have increased to the point where the yaw moment due rudder was equal to the opposite yaw moment due fuselage angle. As shown in the report, that was a significant angle, presenting much more of the airframe and nacelles to the airflow than is normally the case. Also, with the sideslip angle at around 30 degrees, the prop thrust is acting at this angle, rather than directly along the flight path, so the reduction in thrust, also considering the off-optimum incidence angle into the props, could be anything up to 50% (my estimation). |
I don't believe you are reading the report as closely as you could Frankly, think there is a big question about the relevancy of 140 Kt. The best rate climb speed is 121 Kt. Surely, there is no need (in an emergency situation) to go faster. And if the simulator was not relevant and the loading not able to be represented, then what on earth was the ATSB doing it for?? |
Hey Groggy, I think the ATSB did a good job ruling out the "power lever migration" theory. The witness marks in the roof of the building, the prop damage and the audio recording all showed that both engines were at full power.
|
Somebody asked why, with both engines supplying full power, the aircraft couldn't still climb 1. The whole Essendon incident occurred in 12 seconds. a) I don't think that fits with the meaning that the SIM pilot was meaning when he said "your leg WILL give out...." and b) as noted above, I believe this refers to the 140 Kt condition. I don't believe this refers to the 100 - 112 kt (ish) speeds of this flight. I think the SIM pilots comment " The yaw on take-off was manageable" refers to this flight condition. Secondly, the ATSB side slip angle calculation and hypothesis is seriously flawed. |
Originally Posted by FGD135
(Post 10256905)
Hey Groggy, I think the ATSB did a good job ruling out the "power lever migration" theory. The witness marks in the roof of the building, the prop damage and the audio recording all showed that both engines were at full power.
Yes saw that however don’t forget that a windmilling constant speed propeller would have considerable force spinnnng at 2000 rpm. Groggy |
Old Akro,
What was flawed about their sideslip angle calculation? The relative positions of the impact marks on the roof would make for a pretty accurate calculation. I didn't look too closely at their photographic pixel method, but the impact marks were pretty definitive. |
Old Akro, as you are asking lot of questions and providing no answers: why did the PIC broadcast 7 maydays? Wouldn’t his attention not be better utilised by flying the aircraft? Who, apart from those on the aircraft , were going to help him with his predicament? |
Groggy,
Yes, but a big big difference in the blade angle and resultant damage signature to a prop that is windmilling compared to one that is delivering power. |
It’s a good report in my view (apart from the odd spelling mistake). Full left trim not detected prior to take off. Possible confusion and mistake that engine had failed. But why was full left trim set in the first place? Three complete rotations were needed. Who would have done that? Why would they have done that? It wasnt maintenance as the aircraft had flown after its last maintenance. So what was it? |
FGD: You keep talking about ‘sideslip’. Wouldn’t an uncorrected rudder trim cause a ‘skid’? |
why did the PIC broadcast 7 maydays? |
Leady, slip and skid occur during a turn, when the turn is not perfectly coordinated.
Sideslip is when the aircraft is going through the air "somewhat sideways". It can have a significant sideslip angle but still be travelling in a straight line - with zero yaw and all forces in equilibrium! |
Akro - it didn't climb because he stopped piloting. Fly the aircraft first and worry about mayday mayday mayday later.
Wombat, seriously? The report says that the pilot made 1 Mayday transmission in witch he repeated Mayday 7 times. A perfectly human response to an extreme situation I would have thought. Maybe so AKRO - but NOT a perfect response by a well trained pilot who is taught to fly the bloody aeroplane. Next time I'm a passenger I hope I don't have a pilot who gives your definition of a perfect response to an anomoly. I know you're trying hard to defend a buddy here, but to say that screaming Mayday 7 times while his machine NEEDS flying is an expected and understandable response really is a stupid thing to say. As for the Pilots leg giving out holding against the rudder trim - how long was it airborne for again?? Seconds wasnt it?? I doubt the leg gave out. |
I didn't look too closely at their photographic pixel method |
Originally Posted by Old Akro
(Post 10256945)
Wombat, seriously? The report says that the pilot made 1 Mayday transmission in witch he repeated Mayday 7 times. A perfectly human response to an extreme situation I would have thought.
aviate, navigate,communicate? |
All times are GMT. The time now is 05:59. |
Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.