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If you have a choice at your airline - Airbus or Boeing?

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If you have a choice at your airline - Airbus or Boeing?

Old 7th May 2011, 14:43
  #21 (permalink)  
 
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Originally Posted by Slasher View Post
the 320 is a really seriously
paranoid robotic C3PO on pure steroids with a massively
humongous arrogance problem.
No bias there then...

You are aware you can turn the FMC off on an A32/3/4/80 series and it hand-flies rather well, aren't you? As I said on another thread, "C-3P0" didn't try to tell Capt. Sullenberger how to do his job, did he?

Originally Posted by SKS777FLYER View Post
Also, the accident aircraft had earlier in its' life been involved in a pretty significant in flight upset. So much so that AA pulled or downloaded the flight recdorder data and submitted it to Airbus for guidance. I do not know what guidance AA received from Airbus... but Airbus DID NOT share their calculation that the vertical stabilizer of the aircraft had been subjected to ULTIMATE load factor during the upset. That came out during the discovery phase of the accident aircraft legal battle.
Come on - this isn't relevant. In the AA587 incident itself the VS stayed on for a time despite being subject to loads in excess of Ultimate Design Load, which means that *despite* this earlier incident, the VS was still attached strongly enough to stay on if the aircraft was flown within - or even slightly beyond - it's design limits. The PF in that case was attempting to use a technique designed for DC-9/MD-80 series aircraft which have a completely different configuration (rear-engine, T-tail) - one that requires far less rudder authority than the type (wing-mounted engine, traditional empennage design) he was flying.

The very existence of the B787 renders the composite vs. aluminium part of the A v. B flamewars moot in any case.

Not a pilot myself - but if I were, I'd be happy to take an office seat in either manufacturer's machine. But before I even set foot in one, I'd make the time to fully understand every aspect of how the bird is designed to work and try to discover any "gotchas" (which all aircraft have) relevant to the type - on top of any official training I'd received. The vast and sweeping majority of modern accidents attributable to pilot error these days seem to come from a lack of that kind of knowledge.
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Old 7th May 2011, 17:12
  #22 (permalink)  
 
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I want to be careful not to drag things off-topic, so I think I'm going to limit myself to one reply here...

Originally Posted by SKS777FLYER View Post
Hello Dozy,
Yes getting all the knowledge you can is great in theory, somewhat difficult in application, particularly in the early 90's thru the early years of this century.
Possibly, but I'm talking about things that should be easy to discover by judicious use of the manuals - such as :
  • Unlike the 737-300 model, the 737-400 model takes it's aircon input from both engines (Kegworth)
  • Inputting a single letter into the FMS of a 757 will give you a list of options, and hitting "Enter" twice will give you the first (Cali)
  • Holding the A/THR disconnect switch for more than 15 seconds will completely disable A/THR, and it can only be re-engaged on the ground (Habsheim)
  • Popping a CB related to the nosewheel will also disable Takeoff Config Warnings (Spanair Madrid)

Things of that ilk. While there has been no shortage of expressed opinion that losing the F/E (and thus an extra pair of eyes) may have negatively affected safety, I think that what may be more important is the loss of the career progression which meant that a lot of pilots spent some time as F/Es at the beginning of their careers - and spent that time having to learn the inner workings and foibles of their aircraft. That learning can still be done without spending time as an F/E, but when the business case is to get newly qualified pilots into the right-hand seat (and thus getting the airline a return on investment) as quickly as possible, it may be a dangerous thing to neglect.

Also, we're in the second decade of the 21st century now. Even senior pilots in their 30s and 40s will have spent at least some of their formative years around computers. Computers occupy a place in the human world that no-one could have conceived back in the '60s and early '70s, when they occupied a space in culture where computers were room-sized devices pored over by men in white coats (or later, coffee- and pizza-stained T-shirts), or largely informed by sci-fi stories about rogue computers trying to take over the world. Pilots who qualified back then would naturally have been very suspicious of such a device sharing the cockpit with them to the extent it was when the A320 first hit the market. These days we're more aware of their usefulness, their limitations, and what they are and are not capable of.

The A320 has spawned a successful series of aircraft which carry millions of people around the world every day, and Boeing's latest models, even while they retain the "classic" flight deck controls and "pilot-centered" philosophy, are reliant on computer-driven feedback to acheive the feel they do.

I can assure that no pilot I encountered in line flying over the decades and just a very select few in the nether regions of the training and flight ops centers had the vaguest clue that at less than maneuvering speed (AA accident A300 was flying at, I believe significantly less than maneuvering speed) that it was remotely possible for a pilot to cause the vertical stabilizer of a modern jetliner to separate from the fuselage..... particularly the latest flight control computer assisted aircraft. We were trained about the protective safety provided by rudder limiters, etc. etc.
It was not until AFTER the tragedy that Boeing, and probably AB as well provided information in flight manuals about weak tail feathers on jet transports, weak as related to ANY rudder doublets, and rudders only suitable for use in relatively low speed single engine flight.
Then that was a failure of the industry as a whole - and in a way we come back to a possible desire for pilots to have some grounding in engineering. The BOAC 707 that practically disintegrated in mid-air near Mount Fuji should have been a warning that the stresses an airliner can be subjected to in mid-air can in very short order cause a catastrophic failure. The story of the DH Comet was a salutary lesson in the dangers of material fatigue - that if you apply pressure in opposite directions over a period of time, materials can fail. The knowledge was out there, but it appears few put two and two together in this case.

Also, since the story of the DC-10 and the "Gentlemen's Agreement" was made public, it's also been common knowledge that manufacturers will go to any length to downplay potential problems with their product - so while you can usually trust them when they tell you how to fly the thing, it's probably a good idea to keep in the back of your mind that they may not be telling you the whole truth.

So if it became common knowledge that in an aircraft configured in the manner of the A300 (which seems to be the standard configuration of most modern large jet transports these days), that if you push the rudder pedal one way, then the opposite way - and repeat this action enough times - that the VS will break off, there'd be a public outcry. Which manufacturer would risk being the first to admit that was the case? Their orders would dry up before you could say "commercial suicide"!

You don't get any shivers when you learned that the vertical stabilizer of the aircraft that crashed in NY had already flown beyond it's design limit a fact learned by Airbus, but not shared with its' customer??
It's certainly not an ideal situation, and if it had turned out to have any impact on the AA587 incident itself, then I'd be at the head of the group calling for investigations and prosecutions. But on the other hand, you can speculate that Airbus had sufficient data to conclude that the previous incident would not have had a detrimental effect on the lifespan of the airframe (which, given the VS stayed on past Ultimate Design Load, the evidence suggests strongly was indeed the case).

As to getting the most knowledge about the aircraft a pilot flies, I might remind you that Airbus AND Boeing BOTH were putting together composite tails in those early days with insufficient knowledge of the composite assembly process; otherwise they would not have encountered delamination of layers of composite material, which they BOTH used a bandaid technique of basically clamping the delaminated structures back together with rivets during the build.
But as yet there has not been the loss of a transport-class airframe due to composite failure alone, and it seems that they're getting to grips with the peculiarities of this new material over time, just as they did when aircraft manufacture went from wood to aluminium. Indeed, it was the loss of the Comet that woke the industry up to the fact that aluminium was not a panacea when it came to strength in aircraft construction (though it's likely some engineers probably nodded sadly to themselves when the cause of those crashes was discovered).

Ultimately, the passengers put their lives in the hands of the pilots and crew, and even the best pilot is, to some extent, putting his or her life in the hands of the engineers who designed the aircraft they are flying. Ultimately it becomes a matter of trust, and the sad truth is that commerce cannot cheat physics. With that in mind it is encumbent on pilots and engineers to do the best they can with the knowledge that's available.
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Old 7th May 2011, 18:09
  #23 (permalink)  
 
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DozyWannabe

What a great post! Thank you Sir, or Madam.

Your quote below should be emblazoned on every airline manager's coffee cup and door:

the sad truth is that commerce cannot cheat physics.
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Old 8th May 2011, 01:20
  #24 (permalink)  
 
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The A300 was not "the latest flight control computer assisted aircraft". Recent report about the A320 event in Canada shows that even newer designs still can have rudder induced control problems.

Agreed about Va. AB, as well as Boeing, produced information about rudder sensitivity after the accident.

The tail failed at 2.03(?) load factor, even after the previous incident.
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Old 8th May 2011, 03:10
  #25 (permalink)  
 
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If the choice is Airbus or Boeing, I'd go Boeing.

..... But, prefer Gulfstream.
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Old 8th May 2011, 03:46
  #26 (permalink)  
 
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I cannot endorse more heartily Boeings Philosophy.


The Pilot should be in full control of the Aircraft, without restriction at all times.



How can you argue with that. The B777 has a switch that disables all 'protective' flight control laws. Boeing protected their philosophy.


I think that many of the Airbus protections are excellent. But you should be able to turn it all off.


And how is non back driven autothrottles and non connected control sticks an advance ?
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Old 8th May 2011, 07:53
  #27 (permalink)  
 
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And you can turn all those protections off on the Airbus, but there is absolutely no reason to do so.
Are you rated on the Airbus?
It just takes a sim session or two to convince you.
Back driven throttles, what are those?

My airline over the years went from Boeing 737 to Airbus 320.
I know not one pilot who really wants to go back to the 737, the tractor.
Why?
Tray table.
Tray table.
Comfort.
Good design ergonomics.
Big flight deck.
Protections.
Did I mention tray table?

Of course the Boeing is a good machine and we all enjoyed flying it.
It certainly has its plus points, it is not inferior at all.
The VNAV and autothrust work much better (not talking about moving thrust levers, which are obsolete on the Airbus and rightly so), the FMS is more intuitive.
But on the whole I much prefer the comfort of the Airbus.
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Old 8th May 2011, 08:59
  #28 (permalink)  
 
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Cannot see why some AB pilots praise the throttle system so much. The B. system is so easy, natural, intuitive ...
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Old 8th May 2011, 09:34
  #29 (permalink)  
 
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Airbus or Boeing?

As long as plane is well maintained, pay is good and roster decent, I don't care if it's 380, 738, G550 or L-410 Turbolet.

Originally Posted by bubbers44
The vertical stab that was defective and patched out of the factory broke where the repair was done.
Never, ever let facts get into way of a good story.

Originally Posted by NTSB report on AA587, page 135
No deviations from the original design and materials specifications were found in the vertical stabilizer (including the repair to the left center lug area that was made during manufacturing) that would have contributed to the vertical stabilizer separation.
Originally Posted by NTSB report on A587, page 136
In the structural analysis of the accident condition, computational models predicted that, with increasing aerodynamic loads, the right rear lug would experience increasingly higher stresses that would eventually exceed the strength of the lug material and the right rear lug would be the first structural component to fracture
Originally Posted by NTSB report on AA587, page 135
Fracture features and damage patterns on the right forward, center, and rear lugs were consistent with overstress failure under tensile loading. The right rear lug, in particular, had fracture features that were consistent with failure in the cleavage-tension mode. Fracture features and damage patterns on the left forward, center, and rear lugs had features that were consistent with the vertical stabilizer bending to the left after separation of the lugs on the right side.
Good enough?
Originally Posted by SKS777FLYER
Also, the accident aircraft had earlier in its' life been involved in a pretty significant in flight upset. So much so that AA pulled or downloaded the flight recdorder data and submitted it to Airbus for guidance. I do not know what guidance AA received from Airbus... but Airbus DID NOT share their calculation that the vertical stabilizer of the aircraft had been subjected to ULTIMATE load factor during the upset. That came out during the discovery phase of the accident aircraft legal battle.
You can always count on lawyer to discover what accident investigator missed. Would you be so kind to provide reference to that claim of yours? I can give you something written by NTSB:
Originally Posted by NTSB report on A587, page 135
a detailed inspection of flight 587ís wreckage, including an extensive examination of the vertical stabilizer main attachment fitting fractures, revealed that each main attachment fitting had features that were consistent with overstress fracture and exhibited no evidence of fatigue features or other preexisting degradation.
Originally Posted by SKS777FLYER
I can assure that no pilot I encountered in line flying over the decades and just a very select few in the nether regions of the training and flight ops centers had the vaguest clue that at less than maneuvering speed (AA accident A300 was flying at, I believe significantly less than maneuvering speed) that it was remotely possible for a pilot to cause the vertical stabilizer of a modern jetliner to separate from the fuselage.....
That, sir, is quite appalling. Pilots of my class were certainly made aware that under no circumstances is cycling any flight control, at any speed, on any fixed-wing aircraft useful and can turn out to be lethal. It's not just tails that were in jeopardy, stories of gliders shedding wings through aircraft-pilot-coupling were used to illustrate the point. Of course, you have to be quite familiar with concepts of dynamic stability and pilot induced oscillation to appreciate the lesson. That was before they let us sit in mighty Cessna-150 and yet i find the "If you find yourself stirring the controls, give it up, you're probably fighting no one else but yourself" advice useful even when hand flying the A320. Go figure.
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Old 8th May 2011, 12:03
  #30 (permalink)  
 
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Cannot see why some AB pilots praise the throttle system so much. The B. system is so easy, natural, intuitive ...
DJ77, are you rated on the Airbus?
Anyway, I'm not praising the system, I just say it works quite well. And if you really want to manually adjust the thrust, you press a button and presto.
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Old 8th May 2011, 14:16
  #31 (permalink)  
 
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Originally Posted by stilton View Post
The Pilot should be in full control of the Aircraft,
He or she is in the A320+ series too...

without restriction at all times.
Honest question here - what do you think the protections are and when do you think they kick in?

I think that many of the Airbus protections are excellent. But you should be able to turn it all off.
If something's gone wrong with the system (IMO the only time one should turn them off), they turn themselves off.

Another question one might ask is that if you've got yourself into a position where the protections are working and you need to override them to recover, is it possible there wouldn't be enough time to turn them off and perform the necessary actions?

And how is non back driven autothrottles and non connected control sticks an advance ?
Not an advance or step backwards, just a different philosophy. We've been through this so many times now that it's painful, but backdriving the sidesticks could theoretically prevent the pilot(s) from recovering the aircraft if the controls are wired up in reverse (which has happened). It would be difficult, if not impossible to get enough leverage to override the force feedback system due to the way the sticks are positioned. Thus far no mechanic has inadvertently wired a 777 yoke up backwards, but that doesn't mean it will never happen...

Regarding moving throttles, much has been made of their tactile feedback, the lack of which is controversial in the Airbus system. But moving throttles didn't help those poor Turkish guys in Holland.
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Old 8th May 2011, 14:48
  #32 (permalink)  
 
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PENKO:
DJ77, are you rated on the Airbus
No I'm not and never was. That's why I ask. I don't intend to criticize, just to understand. I note you are not praising the system.

I am praising the system I used on the 777: Not quite happy with what the system is doing ? No need to press any button, just move the throttles a bit to get what you need and when you are happy again, let them go and mister Computer will take over gracefully. That's really user friendly.

DJ
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Old 8th May 2011, 16:11
  #33 (permalink)  
 
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DJ77, I didn't mean to sound too harsh
Assuming that the autothrust on the 737NG is similar to that of the 777 I quite agree with you that it is very user friendly. If you don't like what it's doing, you just help it a bit.

In that sense I did have to get used to the lack of thrust feedback on the Airbus and to be honest, it did feel weird the first couple of hundred hours to fly an approach in rough weather without the moving thrust levers. But after a while you get used to it to the point that you don't miss it anymore. I know exactly what the autothrust is doing by the engine sound, seat of the pants, engine instruments etc.

Also and more importantly, there is less need to 'help' the autothrust on the Airbus, because in windy conditions the target IAS on approach is never ever fixed. This is due to a nice protection called GROUNDSPEED MINI. One second the bug is at 135kts, then it moves to 140kts, then back to 133kts, it just varies with the headwind component to maintain a constant groundspeed. This is radically different from the Boeing. It's nice to see how the autothrust works together with the FMGC in this. The less you interfere, the better it works. (In more than 3000 hours on the Airbus I have only once had to correct the autothrust because it was giving me a speed slightly below Vapp)
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Old 8th May 2011, 16:49
  #34 (permalink)  
 
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PENKO, many thanks for your detailed answer. I understand that the AB system has its own skillfull merits. On a turbulent approach, the 777 also tends to maintain an average airspeed higher than Vapp but I only have suspicions about how it is done. Not as clever as using groundspeed anyway.

PS. I didn't find you harsh at all so never mind.

DJ.
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Old 8th May 2011, 20:02
  #35 (permalink)  
 
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No attempt to stir the pot, but as a passenger I would like the aircraft to take control if the pilot fails.

E.g. the aircraft computers are welcome to do a last second intervention avoiding a collision or controlled flight into terrain.

Category:Accidents and incidents involving controlled flight into terrain - Wikipedia, the free encyclopedia

Why not? Maybe a natural fear for machines increasingly ruling mankind ?

Last edited by keesje; 9th May 2011 at 12:06.
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Old 9th May 2011, 20:08
  #36 (permalink)  
 
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..."C-3P0" didn't try to tell Capt. Sullenberger how to do his job, did he?
No thank christ - it left him alone with B HYD and the gamestick to do what he had to do.
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Old 9th May 2011, 20:46
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I flew 737-3/4/5 for 9 years, and was very used to it. It stopped surprising me after about 7. I've also done sim checks on 737-200 and 737-800. I'd even stopped noticing the trim wheel rattling round and the wind noise above 280 knots (actually, thinking about it, it was because we lowered the cost index and never flew above 280 knots).

I've now flown A319/320/321 for 10 years. It took me about half an hour to get used to it. I think it's excellent. I don't think I've ever needed the protections, except in the simulator, I've never had to pull full back (that is FULL back as hard as you can) and firewall the throttles (that is FULL forward to the stop) to escape from terrain (though I like the fact that you can and the aeroplane will do everything it can), I've never had an ECAM as confusing as the ones that they've thrown at us in the sim (and I've not had one in the sim that I've not managed to puzzle out), I've never used the RAT for emergency hydraulics and electrics. I've had one abandoned take-off in that time, miscellaneous electrical glitches, most of which were resettable, I've ended up poling it around at circling minima breathing prayers of thanks that the autothrottle will look after the speed whilst I point it where I want it to go. Yeah, the Boeing you can fly like a "real" aeroplane - but in poor visibility at 600', I'll take all the help I can get. This isn't (as somebody described it on one of the other fora) willy-waving - this is about safely transporting people from A to B.

So basically, give me an Airbus. If I want to fly a real aeroplane, I'll go and rent a Stearman or something. But I forsook being a "real" pilot when I started flying down lines on computer screens. An Airbus is better at helping me keep my job, which I would be the first to acknowledge is not being a "real" pilot at all.

(Yes, I do still have those skills, last time I was checked ... and they do still need to underlie our operation of the airliner.)
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Old 9th May 2011, 21:02
  #38 (permalink)  
 
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Well having flown both A&B , both of which I really enjoyed I would plump for the Airbus! I don't subscribe to one being better than the other just different. The boeing is much more simple to study and therefore non normals are pretty straightforward while the bus is tricky to study and requires more thought! As for the AA accident in NY, I was always taught from day one on any jet to be very careful with the rudder, the aircraft type wasn't the problem!!

Bottom line though is I would fly either for the right roster!!
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Old 9th May 2011, 21:12
  #39 (permalink)  
 
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If I want to fly a real aeroplane, I'll go and rent a Stearman or something. But I forsook being a "real" pilot when I started flying down lines on computer screens. An Airbus is better at helping me keep my job, which I would be the first to acknowledge is not being a "real" pilot at all.
I have to say yeh, well said. My thoughts exactly.

BTW how much do they charge for hiring out the Stearman?
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Old 9th May 2011, 23:01
  #40 (permalink)  
 
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On a turbulent approach, the 777 also tends to maintain an average airspeed higher than Vapp but I only have suspicions about how it is done.
It is designed to quickly increase thrust for speeds lower tha Vref and more slowly reduce thrust for higher speeds.
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