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Automation vs Seat-of-the-pants-flying talking as devil's advocate - so no abuse plea

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Automation vs Seat-of-the-pants-flying talking as devil's advocate - so no abuse plea

Old 14th Sep 2013, 02:05
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from full automation to stalling in direct law on an airbus impossible
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Old 14th Sep 2013, 02:29
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@PA - The FCOM manuals for Airbus FBW types clearly state that outside of Normal Law, Alpha protections are lost and the aircraft can be stalled. And they always have.
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Old 14th Sep 2013, 02:48
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hence the importance of hand flying...all it took was one iced pitot tube...unreliable airspeed is no reason to crash any airplane
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Old 14th Sep 2013, 02:55
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Originally Posted by Pugilistic Animus
...all it took was one iced pitot tube..
Not quite - it took all three.

hence the importance of hand flying
Specifically at high altitude in that case.

unreliable airspeed is no reason to crash any airplane
Agreed - but there was a lot more to that accident than overreliance on automation!
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Old 14th Sep 2013, 02:59
  #165 (permalink)  
 
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regardless of my error....hand flying is imporyant so one can quickly adapt to rapidly chsnging conditions
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Old 14th Sep 2013, 03:01
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the most important training is your primary training not your atpl...
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Old 14th Sep 2013, 03:04
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And I'm in total agreement with you. But given that, the PF in that case was a highly experienced glider/sailplane pilot and as such probably had more basic stick-and-rudder experience than most of his peers. The training and experience he lacked was specifically on manual handling at high altitude.

As I said, it's a lot more complex than just trotting out the "Children Of The Magenta" meme again...
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Old 14th Sep 2013, 03:24
  #168 (permalink)  
 
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we are talking IFR
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Old 14th Sep 2013, 03:31
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dozy

douglas strong...unlike airbus strong where the vertical tail falls off

douglas strong , you know like all the DC8's that are still flying...and DC3s, and the DC4s which are fire bombers.

how many 707s and comets are still in use (not military)? not many

I stand by what I said...and cables that work hydraulics work just fine in really big planes.

comet...metal fatigue

737 pop top?

yeah...I'll take douglas...esp single digit dougs
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Old 14th Sep 2013, 03:55
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@PA - IFR/VFR isn't the issue - the difference is how a swept-wing jet handles at cruise as opposed to at low altitude.

Originally Posted by flarepilot
douglas strong...unlike airbus strong where the vertical tail falls off
If you want to take a DC-10 up and subject the vertical stab to 1.8x ultimate design load to prove that point, then be my guest - just please understand why I won't be standing anywhere in the vicinity.

douglas strong , you know like all the DC8's that are still flying...and DC3s, and the DC4s which are fire bombers.
Not pressurised in the case of the latter two. And the venerable VC-10 has been flying in RAF service for about as long as the DC-8.

how many 707s and comets are still in use (not military)? not many
Well - to be fair most remaining 707 airframes have been requisitioned by the military for spares and the Nimrods were set to fly another 30 years before our current government decided to scrap them in favour of buying second-hand Rivet Joints.

I stand by what I said...and cables that work hydraulics work just fine in really big planes.
Fine, but I respectfully disagree.

comet...metal fatigue
Only the first model - and the VC-10 and BAC 1-11 that followed had fuselages machined from aluminium billets - there have been none tougher either before or since.

737 pop top?
Specific to the way Aloha used them - if they'd used DC-9s the same would have happened.

yeah...I'll take douglas...esp single digit dougs
Fine, but given the choice, I wouldn't.

Anyway, as fun as this willy-waving is, it's somewhat beside the point. The undeniable truth is that even with the myriad problems facing the industry, it is statistically far safer than it was when DC airliners ruled the sky. I agree with you that there needs to be more attention paid to handflying skills by the industry, but to blame technological advances for this state of affairs is putting the cart before the horse.
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Old 14th Sep 2013, 03:59
  #171 (permalink)  
 
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IMC vs VMC is a huge difference!
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Old 14th Sep 2013, 04:57
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I flew that Aloha 737 over 100 hrs I am sure before Aloha got it from us. Mostly over FL330. We had an incident where the crew got low landing at ONT and hit high voltage power lines and diverted to LAX. The power lines caught their landing gear causing faults that caused an overun. Reinforcement to the belly of that ac might have kept the aircraft intact with the upper skin torn off.
I always trusted Boeing aircraft so stayed with them for 25years with no major problems and about 16,000 hrs in Boeing aircraft. I flew the MD80 for a bit also.
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Old 14th Sep 2013, 08:57
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dozy...now I know you are wrong...the DC9 had something the 737 didn't have...take a look at the upper fuselage and the finger like metal...then look it up.

heh.
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Old 14th Sep 2013, 22:37
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Originally Posted by Pugilistic Animus
IMC vs VMC is a huge difference!
I know - but *in that case* the more problematic lack of experience was high-altitude manual handling, where the aircraft's response in the 3 axes will be far more sensitive due to the lower-density air. That crew's only manual handling experience was takeoff to a couple of thousand feet and approach/landing.

Originally Posted by flarepilot
dozy...now I know you are wrong...the DC9 had something the 737 didn't have...take a look at the upper fuselage and the finger like metal...then look it up.
Possibly, but if the corrosion had occurred either before or at the apex of the finger lap, then you might have had a scenario which was the same or worse, due to pressure buildup along the finger laps that were holding.
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Old 14th Sep 2013, 22:57
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mainly it's about reduced aerodynamic damping...mean one must be gentle with the flight controls...in IMC...at night in turbulence....there are six axes
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Old 15th Sep 2013, 00:18
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Sure. Or, (as in the case of AF447) leave the controls alone* and monitor aircraft behaviour until such time as a correction needs to be made.

* - but cover them and be prepared to use them

Last edited by DozyWannabe; 15th Sep 2013 at 00:28.
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Old 15th Sep 2013, 00:39
  #177 (permalink)  
 
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I have never flown an Airbus...but I don't think that that is the procedure for unreliable ASI.

with no AP the plane will enter a spiral dive without manual intervention
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Old 15th Sep 2013, 00:40
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dozzy...possibly the sun will explode.

possibly I will be elected POTUS

now look up the finger laps/joints and how they would SHOW a problem if there were one...

douglas used more rivets
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Old 15th Sep 2013, 00:59
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@PA - The Airbus UAS procedure is posted in the AF447 threads. And here:
http://www.bea.aero/docspa/2009/f-cp...nexe.06.en.pdf

The aircraft will not spiral dive for some time if the trimmed pitch and power are OK, which at that point they were.

Originally Posted by flarepilot
now look up the finger laps/joints and how they would SHOW a problem if there were one...

douglas used more rivets
Hi - yes, I know. I did look things up as you requested and found a very interesting academic paper on the subject here:

http://xa.yimg.com/kq/groups/1451308...wift_Comet.pdf

Admittedly the equations go over my head, but the prose explains it well. It transpires that Douglas's approach on fatigue was very much informed by the information shared from the Comet 1 investigation.

Now - the problem in the Aloha case was not with the design so much as it was the way the aircraft was maintained by the airline (though the NTSB stated that the airline were not to know that their methods may be problematic). It was the disbonding, re-bonding and re-riveting performed as part of an overhaul that caused greater opportunity for corrosion and fatigue. In fact one of the passengers did see a small crack before she boarded, but did not speak up as she assumed it was known about.

Additionally, sometimes making things tough is not the way to do things - witness the MD-11 hard landings that sheared the spar at the gear attachment location.

Last edited by DozyWannabe; 15th Sep 2013 at 01:07.
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Old 15th Sep 2013, 01:06
  #180 (permalink)  
 
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The autopilot had to be disconnected on Apollo 11 to prevent a crash. Apollo 13 would have been a loss without pilots.

No autopilot today can even handle something as routine as mountain wave. That's just one of many examples. No autopilot today can get an airplane out of an unusual attitude reliably. They can however put you in one.

Drones are not pilotless, they are remotely flown and still crash a lot.

Airliners still on the drawing board are still based on the 2 pilot concept .

You guys thinking large commercial jets will be flying pilotless in 20 years are smoking the funny stuff.

Last edited by 737er; 15th Sep 2013 at 01:09.
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