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Old 12th Mar 2017, 03:33   #541 (permalink)
 
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In QF1's case, if there had been fatalities, the sod in seat 0A would have been legally required to carry the can, CAR 224 notwithstanding.
It does make you wonder where the guy in 0A does sit, given the comments from the report. Bolding mine.
Quote:
Significant latent failures

Significant latent failures associated with Qantas Flight Operations Branch activities were:

• Company-published information, procedures, and flight crew training for landing on water-affected runways were deficient.

• Flight crew training in evaluating the procedural and configuration options for approach and landing was deficient.

• Procedures and training for flight crew in evaluating whether or not to conduct an emergency evacuation were deficient.

• Procedures and training for cabin crew in identifying and communicating relevant information during an emergency were deficient.

• The processes for identifying hazards were primarily reactive and informal, rather than proactive and systematic.

• The processes to assess the risks associated with identified hazards were deficient.

• The processes to manage the development, introduction and evaluation of changes to operations were deficient.

• The design of operational procedures and training were over-reliant on the decision-making ability of company flight crew and cabin crew and did not place adequate emphasis on structured processes.

• Management culture was over-reliant on personal experience and did not place adequate emphasis on structured processes, available expertise, management training, and research and development when making strategic decisions.

Responses to the pilot survey, along with information obtained during interviews, indicated that the Qantas One flight crew were not atypical of most other company B747-400 pilots. There was, therefore, an unquestionable link between the performance of the crew and the company flight operations system in which they trained and operated

The flight crew did not use an adequate risk management strategy for the approach and landing. Given the minimal level of procedures and training provided to the crew regarding landing on water-affected runways, they were not equipped to appropriately handle the situation they faced. It is, therefore, unreasonable to expect the crew to have developed an adequate risk management strategy for the approach and landingBoeing's opinion was not sort until after the event.
Again from the report
Quote:
Boeing - we do not advocate intentionally increasing brake temperatures as a means to increase carbon brake life. We have concerns that such techniques could result in increased occurrences of fuse plug melting and dispatch delays for brake cooling. Additionally, some of the techniques we have heard discussed, such as reduced landing flap settings and the use of idle reverse thrust, have a negative impact on airplane stopping performance. Therefore, these techniques are not recommended as standard practice…

Boeing did not support the use of idle reverse thrust as a standard practice for normal landings or for increasing brake temperatures of carbon brakes. Further, they were concerned with the human factors implications of having idle reverse thrust as the standard practice

There is no evidence that Qantas had sought Boeing’s opinion regarding the safety impact of the new procedures and their potential effect on carbon brake wear. Management personnel agreed that Boeing’s opinion on such issues would be useful, and that they would normally consider the manufacturer’s opinion before changing procedures. Boeing has since stated that it does not support the use of idle reverse thrust as a normal procedure as it increases landing distance. It has also stated that modified braking techniques alone would produce almost as much reduction in brake wear as the combined effect of the flaps 25/idle reverse procedures.

• The performance differences between idle and full reverse thrust, and between flaps 25 and flaps 30, were not fully examined. Such an examination would probably have highlighted the significant differences in landing distance on wet or contaminated runways using these various configurations.

• There is no evidence that a systematic attempt was made to identify all the situations for which flaps 30 and/or full reverse thrust would be more appropriate.

• The term ‘contaminated’ was used in the flaps 25 procedure but was not defined.

There appears to have been no review of the human factors implications of the new procedures. For example, there appears to have been no consideration of the extent to which the use of flaps 25/idle reverse could become a skill-based habit (i.e. ‘ the norm’), and therefore might be used by crews when a more conservative configuration was required.

The post-implementation review of the effects of the changes was shallow, informal, and undocumented. Flight crew were asked in newsletters to provide feedback. Fleet management received limited written and verbal feedback. Although mainly critical in nature, this feedback appeared to be disregarded as the number of sources was relatively small, and many of the sources were perceived to be resistant to change. There was no method of actively obtaining information from flight crew or check-and-training personnel. It is reasonable to conclude that a more detailed and positive feedback program would have identified the strong views of many line pilots about the operational benefits of flaps 30 over flaps 25 (see section 1.7). Such a process should also have identified the lack of flight crew understanding of aspects of the procedures, such as the meaning of the term ‘contaminated runway’.
As much as some people hate the Reason model, when holes line up is it reasonable to place the entire blame (hate the word) on 0A.

The comment that it may become the "norm" seems prescient in hindsight.
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Old 12th Mar 2017, 04:08   #542 (permalink)
 
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The lack of training about the implications of rejected landings and especially the changes to the auto spoilers, auto brakes and autothrottle responses and indications is very significant. Given that we almost never saw these situations on line, an exercise during the triennial cyclic matrix would have been valuable.
A massive human factors fail was the fact that nobody knew who was flying after the attempted G/A. Had even idle reverse been selected the outcome would almost certainly have been OK, a bit scary maybe, because the auto spoiler would have extended the spoilers and enhanced the braking enough to stop her.
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Old 12th Mar 2017, 06:50   #543 (permalink)
 
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Originally Posted by megan
As much as some people hate the Reason model, when holes line up is it reasonable to place the entire blame (hate the word) on 0A.
I never said it was reasonable , I just said that's the way it would have most likely gone down. I'd liken it to Überlingen, the swiss cheese there had more holes in it than a gold-diggers diaphragm, but that didn't stop the ultimate conclusion from occurring. Grieving families need someone to blame, it would be a bit hard, not to mention extremely unsatisfying to try and scream at, vent at, punch or launch a murderous vendetta against an 'Ops Branch'..
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Old 12th Mar 2017, 08:50   #544 (permalink)
 
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So, can I ask the experts on policy, policy implementation, the Flight Manual etc:
Where does the fact where the person in 0A, directs the F/o to go-around, then takes over from him, then elects to discontinue the go-around, the aircraft makes contact with the runway, that disarms the auto spoiler and the autobrake, then touches down on a runway with standing water which is unreported, tries to stop without auto brakes and no speedbrakes up, neglects to select ANY reverse ( let alone idle), no one realises the spoilers haven't deployed so they are faired until the end of the landing roll, and one engine is in forward thrust which is undetected or unreported by any of the pilots.
Who in the hell discontinues a go around anyway? I haven't ever seen any landing data that gives a runway distance required for a discontinued go around, let alone on a contaminated runway.
The only cheese that suits what happened is not Swiss, it's a smelly blue cheese, one that is the product of something well out of the ordinary.
A few minutes earlier the 0A seated person on another aircraft on the other parellel runway carried out a go around which was not discontinued. They landed after a second approach and were in the hotel whilst the other one was checking out the golf course.
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Old 12th Mar 2017, 09:00   #545 (permalink)
 
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Wombat watcher, I think that is an oversimplification of what occurred. I will admit that it is a very long time since I read the report on QF1, but, I think it was the FO as PF who initiated the go-around (2nd one), that decision disabled the auto-spoilers and auto-brakes, not the contact with the runway, the Capt. then sights the runway and takes over and lands the aircraft, albeit well down the runway. By now it was confusion aplenty in the cockpit and no-one knows what the responsibilities are or what they should be looking for.

Yes there were shortcoming all round but it did highlight something which I think still rings true today, that the most dangerous thing in aviation is the accountant mentality.
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Old 12th Mar 2017, 09:15   #546 (permalink)
 
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"When the aircraft was approximately 10 ft above the runway, the captain instructed the first officer to go around. As the first officer advanced the engine thrust levers, the aircraft’s mainwheels touched down (1,002 m along the 3,150 m runway, 636 m beyond the ideal touchdown point). The captain immediately cancelled the go-around by retarding the thrust levers, without announcing his actions. Those events resulted in confusion amongst the other pilots, and contributed to the crew not selecting (or noticing the absence of) reverse thrust during the landing roll. Due to a variety of factors associated with the cancellation of the go-around, the aircraft’s speed did not decrease below the touchdown speed (154 kts) until the aircraft was 1,625 m or halfway down the runway."


Lovett, here it is for you to read and modify your opinion.
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Old 12th Mar 2017, 09:30   #547 (permalink)
 
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PLovett, not quite. The FO was PF, and was looking good till very short final, although a little fast. Entering IMC he then slipped high on slope. The Captain called the go around approaching the flare, at which point the FO advanced the throttles. Suddenly in reasonable vis though, the Captain then decided to cancel the go around (without informing anyone) and retarded three of the four throttles, but missed one which consequently remained set at TOGA. This is what disarmed the auto-brakes. By this stage, thanks to being high and fast on final, attempting to initiate a missed approach and then extending the flare/AoA/nose high attitude into a gentle touch, and having one engine at TOGA, they were a considerable distance from the threshold by the time they started applying manual brakes. The gentle touch assisted the dynamic aquaplaning that then occured, and reverse thrust was not employed.
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Old 12th Mar 2017, 10:33   #548 (permalink)
 
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wtf has QF1 got to do with the King Air crash?
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Old 12th Mar 2017, 10:54   #549 (permalink)
 
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About as much as your post has to do with it!
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Old 12th Mar 2017, 11:02   #550 (permalink)
 
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Was thinking the same, maybe some people just want to show off rather than discuss the KingAir autofeather issue
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Old 12th Mar 2017, 12:19   #551 (permalink)
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EVERYWHERE I've ever worked, the SOPs over ride the AFM/POH
In every OM I wrote or worked under, the OM stated clearly that where there was conflict between the OM and AFM/POH, the AFM/POH information had precedent.

This was to cover a couple situations where a third party not familiar with the AFM/POH published conflicting information in the OM or the AFM/POH was amended that put the OM in conflict with the AFM/POH.

The only SOP that I know off that was against the AFM was in one company who flew a mixed fleet of fixed gear and retractable gear aircraft where the undercarriage up and down calls were standard across the fleet.

Quote:
And that's why CASA changed the laws about 20 years ago to "Accepting" rather than "Approving" Ops manuals. They shifted the legal burden away from themselves to the AOC holder and pilots.
For over 40 years the only part of an OM requiring approval was a CAR217 Part C.

One crucial bit of the approach in QF1 that the ATSB missed and did not comment on, which would have prevented the accident, was during the approach where one of the crew stated, during the investigation, that the runway was only visible to the crew directly behind the sweep of windscreen wipers. I believe that it is a requirement for the runway to be continuously visible to the crew when continuing the approach below the DA.

If they had conducted a missed approach when the continuous visibility requirement was lost, we would not be talking about this today.

Anyway this is completely of topic.

Back to the B200. Auto-feather is there for a reason, especially with Raisbeck 4 bladed props. Use it. End of story.
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Old 12th Mar 2017, 20:50   #552 (permalink)
 
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Originally Posted by megan View Post
Ask away, what is it you want to know about auto feather?

PS: threads often side track in the course towards a destination. Think of it as off track sight seeing. We get there in the end.
with the loss of oil pressure when the engine shuts down, why doesn't the prop feather without the need of a separate system?
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Old 13th Mar 2017, 10:14   #553 (permalink)
 
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Eddie, a lot depends on what the failure was and whether or not the core is still rotating.

With an engine that is shut down and the plane flying along you still get airflow through the engine and you'll see it on the Ng.

Now, since the Ng doesn't stop completely (unless say a bearing fails) the oil pump is still driven and sending oil to the primary governor, which boosts the pressure and the prop keeps spinning.


On the ground if you shut a PT6 down and don't feather it, they'll spin for a long time, stop, and as the Ng has also stopped the blades will feather themselves.


The need for the "separate system" you mention (the auto feather) is not because you cannot feather the prop (there's a lever for that), but if you go back several posts it is due specifically for Vmca certification criteria on specific King Airs.
In short the 4-bladers require autofeather because if they windmill they are VERY draggy. The auto feather system will feather it quicker than relying on the pilot to do it. But, you can still manually feather if the auto system fails (which I've never heard about, it's fairly simple and quite robust).
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Old 20th Mar 2017, 06:09   #554 (permalink)
 
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is there a ' negative torque switch' like there was in Electra ham standard props?
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Old 20th Mar 2017, 09:03   #555 (permalink)
 
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No Sunny, no negative torque switches.

A very basic rundown for you if your interested:
There's a main autofeather system switch, arm test off. Let's say it's switched to arm.
There is a micro switch on each power lever. Their position corresponds to roughly a position that commands 90% N1. With these switches made, the system knows you are commanding high power (pull one or both back and it will disarm the AFX system).
In the AFX system, on each side, there are two torque switches; one set to open at 200 ft/lbs and the other set to open at 400 ft/lbs, as the power is increased.

Now, high power is set and the torque switches are open. You then suffer an engine failure. Tq on that engine drops below 400 and closes the first switch- this disarms the autofeather on the opposite side (you cannot have a double-auto-feather event). Then when the failed engine drops below 200 ft/lbs this will close the second switch- this then commands the dump valve to open and feather the failed prop.
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Old 20th Mar 2017, 09:57   #556 (permalink)
 
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Originally Posted by Sunfish View Post
is there a ' negative torque switch' like there was in Electra ham standard props?
Good explanation from Ramrod for the PT6A autofeather system.

The PT6A is a free-turbine engine, the compressor turbine and compressor are on a different shaft than the power turbine. The latter driving the reduction gearbox and the the propeller. These two shafts are not connected.

On the other hand, Negative Torque Sensing or NTS system is installed on a single [spline] shaft like the TPE331 engine. Where all engine components (compressor, power turbinne, gearbox & propeller, accessories, etc.) are geared to that one shaft.
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