garpd From UK - Scotland, joined Aug 2005, 2887 posts, RR: 4
Reply 3, posted (4 years 8 months 3 weeks 2 days 18 hours ago) and read 34131 times:
Coming to an immediate stop from 168MPH is going to kill you instantly. Regardless of what is around you.
People die at 70MPH sudden stops in car accidents due to internal injuries. Though it takes a little while.
But at 168MPH, the g-forces would be utterly devastating. I think we can safely say it is unlikely anyone survived the impact for more than a few seconds.
Trin From United States of America, joined May 2011, 172 posts, RR: 0
Reply 4, posted (4 years 8 months 3 weeks 2 days 18 hours ago) and read 34023 times:
Quoting robertm46 (Reply 302): That is how you get to 38,000 ft even it you don't intend to.
Incorrect. I will be another to ask - did you read the BEA report?
"Around fifteen seconds later, the speed displayed on the ISIS increased sharply towards 185 kt; it was then consistent with the other recorded speed. ***The PF continued to make nose-up inputs.*** The airplane’s altitude reached its maximum of about 38,000 ft, its pitch attitude and angle of attack being 16 degrees. "
There is absolutely no question of the aircraft "getting to FL380 without intending to".......the PF was continuing to make nose-up commands on the aircraft. For whatever reason.
[Edited 2011-05-27 09:44:49]
"I'd always thought you were a guy." .... "Most guys do." ~The Matrix.
Ralphski From , joined Dec 1969, posts, RR:
Reply 5, posted (4 years 8 months 3 weeks 2 days 18 hours ago) and read 33969 times:
Could the high vertical descent rate have aggravated their hopes of recovery?
Maybe they were in a high speed stall situation for the entire descent (not a dive, but the recovery from a dive). With little forward speed relative to the high rate of vertical fall, the critical angle would remain small and they would need that much more thrust or pitch to overcome the stall. Would you need to be MORE aggresive in the stall recovery in this situation?
"For example, an aircraft may go into a steep dive. At the bottom of the dive the pilot may pull back on the stick to make the aircraft flatten out and then climb. If done too quickly, or because of poor aircraft design, the wings can be pointing up but momentum i.e. gravity, continues to make the aircraft go down. If the wings are pointing up but the direction of travel is down the critical angle is exceeded and a high speed stall occurs."
airtechy From United States of America, joined Dec 2006, 678 posts, RR: 0
Reply 6, posted (4 years 8 months 3 weeks 2 days 18 hours ago) and read 33743 times:
I don't think more pilot training is going to solve these type of accidents. And regards the Peruvian and the Birgenair accidents......although the exact details are different the accidents themselves are similar....nighttime and not knowing which gauges are reliable with multiple alarms going off. The laws of physics have not changed since these accidents.
The procedure to recover from a stall should never....at any altitude....require you to reference anything other than your brain. This accident...even at high altitude....shows you don't have time to do so. Doesn't the 330 even have the equivalent of a stick pusher? Are the stall recognition and recovery procedures all that different from those for a Cessna 150?
I suspect lots of "procedures" will be rethought after this accident. Probably the result will be yet another alarm bell or 20 more pages in the flight manual.
wingnutmn From United States of America, joined Jan 2004, 687 posts, RR: 0
Reply 7, posted (4 years 8 months 3 weeks 2 days 18 hours ago) and read 33762 times:
If the airplanr never spun, the angle of attack was almost always nose up, and a vertical decent of 10 to 11000 ft/min. could they have tail stalled the airplane? i know some planes are unrecoverable once they enter a tail stall. any ideas on that?
Any landing you can walk away from is a good landing! It's a bonus if you can fly the plane again!!
Yes, however I suspect what robertm46 was referring to was just prior to that, on the way up to FL375...
"The airplane%u2019s angle of attack increased progressively beyond 10 degrees and the plane started
to climb. The PF made nose-down control inputs and alternately left and right roll inputs. The
vertical speed, which had reached 7,000 ft/min, dropped to 700 ft/min and the roll varied
between 12 degrees right and 10 degrees left. The speed displayed on the left side increased
sharply to 215 kt (Mach 0.68). The airplane was then at an altitude of about 37,500 ft and the
recorded angle of attack was around 4 degrees."
LTC8K6 From United States of America, joined Jun 2009, 1632 posts, RR: 0
Reply 13, posted (4 years 8 months 3 weeks 2 days 18 hours ago) and read 33341 times:
Quoting casinterest (Reply 10): That's because what you quoted is not the report, that is an article on the report.
Really? I thought Yahoo was the crash investigation authority...
Why in the world would you think that I thought a news article was the actual report?
I compared the article to the BEA report English translation. The English report does not seem to say which pilot was at the controls, for example. I was wondering how the media knew. Simple, they read the French original, while I had to make do with the less detailed English translation.
PanAm1971 From United States of America, joined Aug 2007, 554 posts, RR: 0
Reply 14, posted (4 years 8 months 3 weeks 2 days 18 hours ago) and read 33270 times:
I'm a little troubled that the aircraft was unrecoverable from a stall all the way up at FL380. That should have been plenty of time to get some lift under those wings. I'd love to know why the crew were unable to achieve that. Very sad.
Mir From United States of America, joined Jan 2004, 22658 posts, RR: 55
Reply 16, posted (4 years 8 months 3 weeks 2 days 18 hours ago) and read 32877 times:
From the previous thread:
Quoting zeke (Reply 298): I would be interested to see what the mach number was indicating during the event, as that is taken from the TAT, it appears that the static information was also available. They may have had a valid mach number displayed all the time.
You'd still need some sort of valid airspeed indication in order to get a valid mach number, wouldn't you?
Quoting garpd (Reply 306): The higher you are, the faster the stall speed becomes due to the thinner air.
Depends on what sort of airspeed you're talking about. Indicated airspeed will be pretty much the same, which is what the crew sees and really cares about.
Unfortunately, there's not a lot we can really glean from the report. It would appear that the first stall warnings were erroneous, and driven by the unreliable airspeed and/or AoA indications. After that, I'm not really sure. It would appear that the airspeed returned to its correct values, but then later the crew said that they didn't have any valid indications. So it's hard to really figure out what was going on. The waiting continues....
7 billion, one nation, imagination...it's a beautiful day
casinterest From United States of America, joined Feb 2005, 5645 posts, RR: 3
Reply 17, posted (4 years 8 months 3 weeks 2 days 18 hours ago) and read 32844 times:
Quoting LTC8K6 (Reply 13): I compared the article to the BEA report English translation. The English report does not seem to say which pilot was at the controls, for example. I was wondering how the media knew. Simple, they read the French original, while I had to make do with the less detailed English translation.
From the article.
The Captain was PNF, one of the co-pilots was PF.
From various sources. but wiki speciically hear.
There were three pilots: 58-year-old flight captain Marc Dubois had joined Air France in 1988 and had approximately 11,000 flight hours, including 1,700 hours on the Airbus A330; the two first officers, 37-year-old David Robert and 32-year-old Pierre-Cedric Bonin, had over 9,000 flight hours between them
At 1 h 55, the Captain woke the second co-pilot and said "[…] he’s going to take my place".
At 2 h 06 min 04, the PF called the cabin crew, telling them that "in two minutes we should enter
an area where it’ll move about a bit more than at the moment, you should watch out" and he
added "I’ll call you back as soon as we’re out of it".
At 2 h 08 min 07 , the PNF said "you can maybe go a little to the left […]".
At 2 h 10 min 16, the PNF said "so, we’ve lost the speeds" then "alternate law […]".
The writer just inferred data that was not in either report.
Older than I just was ,and younger than I will soo be.
goblin211 From United States of America, joined Jun 2010, 1209 posts, RR: 0
Reply 21, posted (4 years 8 months 3 weeks 2 days 17 hours ago) and read 32398 times:
Quoting Trin (Reply 4): There is absolutely no question of the aircraft "getting to FL380 without intending to".......the PF was continuing to make nose-up commands on the aircraft. For whatever reason.
Exactly the opposite of what they tell you in flight school. Based on this alone, it doesn't look good for the AF pilots. I just hope they uncover more to not put all the negativity on the pilots.
YULWinterSkies From United States of America, joined Jun 2005, 2249 posts, RR: 5
Reply 22, posted (4 years 8 months 3 weeks 2 days 17 hours ago) and read 32400 times:
Quoting LTC8K6 (Reply 13): The English report does not seem to say which pilot was at the controls, for example.
fyi, both copilots were. the captain had just left his seat and went to rest when the aircraft entered that nasty turbulence zone. They recalled him when the autopilot went off, which took several calls (hardly surprising imo if he had just fallen asleep) ,but he did not sit at the controls, just was in the cockpit supervising and trying to assist the pilots, presumably.
Quoting airtechy (Reply 6): I suspect lots of "procedures" will be rethought after this accident.
Probably, I was reading the readers' comments on Le Monde website about the report.
None are A330 pilots, but many are small plane pilots, or have some experience about flying aircraft, which is a lot more than what I personally have (none). All are unanimous that the pilots should have put the A330 nose down to regain speed, lift and control... Yet, the pilots essentially followed Airbus' recommendations to go nose up.
So, when a manufacturer recommends a procedure that goes against some principles of physics, they'd better be 110% sure of what they are doing. That day, this procedure did not seem to have worked out, so it's almost certain that, as you say, "lots of procedures will be rethought".
Also, one poster mentions without any source that out of 9 pilots who tested that configuration in a simulator, only 2 were successful at taking the aircraft out of trouble. Anybody has any source on this?
sshd From Spain, joined May 2011, 74 posts, RR: 0
Reply 24, posted (4 years 8 months 3 weeks 2 days 17 hours ago) and read 32118 times:
First off, this is my first post in the site, even though I have been reading it for years. Thank to all the great contributors in here (Pihero, Zeke, Pilotaydin...).
After reading the BEA´s report, I don´t know whether they omitted some conversations from the CVR. To me, it´s interesting that when the Captain joined the cockpit, neither the PF nor the PNF mentioned anything to him, apart from "we have no valid indicators".
They clearly didn´t know they were stalling, that´s granted. According to BEA´s report, the Captain joined at 2 h 11 min 40 and the last data happened at 2 h 14 min 28, that´s almost 3 minutes. None of them (including the Captain) mentioned "stall", isn´t that strange? Do you guys think they didn´t even think about it?
: Some observations from the report. Conclusion: At least the PNF was aware that the speed information was invalid. Unclear if the PF or the captain rea
: I'm not a pilot. So take my questions and suggestions with a grain of salt (and be nice about bashing them to the ground, please!). I'm just curious.
: This is just an excerpt, not the whole transcript by any means. BEG2IAH
: I'm not an expert at all, though I have crossed the pond many times, although not via the Atlantic equator (I have done SYD-LAX and back - that was fu
: I guess PF got the stick-shaker but maybe in such a chaos+turbulenc he didn´t really pay attention to it...
: I think cruising altitudes should be the same regardless of the region. From what is known so far, it appears that turbulence should not have exceede
: There is no such single set of "values" that describes "the" coffin corner. On any given airliner and in any given situation, it depends on a number
32 David L
: As I see it, there were two major issues: unreliable airspeed and a stall. Perhaps they were focusing on the former rather than the latter at that po
: There is a small margin of error in flying aircraft at high altitude. However, I'd like to point out first that this is a normal mode of operations i