AF 447 report out
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For everyone who thinks PF blundered in 'neglecting to turn off his FD', remember the drill, and try to focus on when the crew became sufficiently sure of UAS to mention it. For to turn off the FD without knowing if UAS drill obtains, remember that in an emergent situation, it is very difficult to consider 'options' rather than pressure one's self to act decisively. The PF did not turn off his AP, either. It remained for the Captain to switch it off mere seconds before the impact. Please know that in the first several seconds, the solution rapidly lost focus for anyone, even you. It is clear that the plot became lost for both quite rapidly, even PNF lost his confidence quickly.
To follow a drill, one must first establish the need for it. It is not wrong to say that once these pilots got behind, catching up became extremely difficult. The FD seems seductive enough to have tempted PF, and the counter intuitive SW was no help. The planning for this "common" event (UAS), at the program level, seems to me to be arbitrary, even haphazard. The complexity of the challenge was in so many ways artificially induced; at the time when one needed simple, one was deluged, and having no training in the necessary skillset seems to me to be wildly negligent on the part of both Airline and Airframer.
Comes Captain, and he too is immediately drenched in a deluge of data, to the extent that he did not notice some truly simple things.
Is there a ready explanation for the very smooth line of THS increase to max, vice a more herky response to actual (commanded) pilot inputs? It looks graphically as though the THS was deploying to a "target" position, independent of pilot command?
To follow a drill, one must first establish the need for it. It is not wrong to say that once these pilots got behind, catching up became extremely difficult. The FD seems seductive enough to have tempted PF, and the counter intuitive SW was no help. The planning for this "common" event (UAS), at the program level, seems to me to be arbitrary, even haphazard. The complexity of the challenge was in so many ways artificially induced; at the time when one needed simple, one was deluged, and having no training in the necessary skillset seems to me to be wildly negligent on the part of both Airline and Airframer.
Comes Captain, and he too is immediately drenched in a deluge of data, to the extent that he did not notice some truly simple things.
Is there a ready explanation for the very smooth line of THS increase to max, vice a more herky response to actual (commanded) pilot inputs? It looks graphically as though the THS was deploying to a "target" position, independent of pilot command?
Last edited by Lyman; 10th Jul 2012 at 21:48.
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fotoguzzi
In AF447, if someone had said, "classic stall," (and perhaps this was stated at one point) would there have been a better chance that the pilot in command would have thought to lower the nose?
In AF447, if someone had said, "classic stall," (and perhaps this was stated at one point) would there have been a better chance that the pilot in command would have thought to lower the nose?
Training in the airline transport industry was focussed on avoiding the stall rather than recovering from it. This contrasts with light aircraft training where stall recovery is experienced and practiced.
Originally Posted by soylentgreen
If you don't have doctoral-level statistics knowledge and don't understand this, I'd be happy to explain in more detail?
Originally Posted by soylentgreen
Care to explain your "Bad Science" comment?
Because it is based on monumental misunderstanding of aviation and human factors in it. Logically correct conclusion from false premises is still false!
Originally Posted by soylentgreen
Or maybe in either case, we need to consider the human-machine interface as the thing that must change?
Originally Posted by soylentgreen
Get 100 x 3-man crews, and put them in a multi-day full-experience simulator.
Originally Posted by soylentgreen
Fullt-time AOA sensors.
Originally Posted by soylentgreen
From this study, we calculate the ultimate data point: what % of crews survive. And perhaps more interestingly: what % of crews survive for the right reasons.
Originally Posted by Petrolhead
No Clandestino, the radar had not been set up correctly:
Fact that CM1 changed the mode of WX absolutely does not imply it was set incorrectly! It is perfectly normal to change range, elevation and gain to get the complete picture of weather systems ahead!
Originally Posted by Petrolhead
On the Airbus it is possible to have the radar on but not displaying anything - that was my point.
Interim report number two was published on 30. Nov 2009. By that point, it had been clear from AF447 ACARS messages its pitots were blocked. Analysis of 13 similar incidents in cruise was made and all of them happened near the storms but never inside the convective cloud.
Interim report number 3 was issued at 29.07.2011. FDR and CVR were found and analyzed. They absolutely confirmed conclusions of interim2: UAS events happen near the storm tops, not in them. AF447 was avoiding the weather well, G trace shows only light turbulence as speed dropped to unrealistic values, quickly reducing to no turbulence at all. That's definitive proof that no storm penetration occurred!
Originally Posted by Nemrytter
They did - and a bad one at that. Depending on the statistics you use the storm cloud formation that they encountered was in the 'top' 1-3% of all storm clouds in that region during the last 6 years. Cloud-tops up to FL600, temperatures below -90C and very strong convection. Not a great place to fly.
Originally Posted by Cool Guys
If the pilot recognized that the mode change disabled the AOA protection and the consequences having no AOA protection I do not think he would have pulled the stick fully back prior to the plane becoming stalled.
Originally Posted by Cool Guys
The plane was in a non optimum state, the computer recognized this state and implemented some counter measures to supposedly keep the plane flying.
Originally Posted by Cool Guys
A modern computer has a lot of processing power and lots of available memory allowing for a complex program.
Originally Posted by Cool Guys
In complex automated applications we now implement touch screens with pictorial representations of the equipment.
Originally Posted by Good Guys
In this case a message indicating the mode has changed was announced and it is up to the pilot to know the resulting complex changes to the flight controls.
Originally Posted by Good Guys
A display with a pictorial view of the plane with the elevators color changing from green to orange would be a good start.
Originally Posted by sevenstrokeroll
does the airbus have a PITCH HOLD mode(selectable by human pilot) for the autopilot?
Originally Posted by DOVES
I had seen on my radar a chain of cumulus nimbus clouds
Originally Posted by ironbutt57
In normal law the aircraft maintains attitude selected by last stick I put, within certain boundaries
Originally Posted by Nemrytter
As I said on the last page: They flew right into the middle of one of the most intense storms seen in that region in the past 6 years.
Originally Posted by nemrytter
you know bad weather doesn't necessarily mean turbulence
Last edited by Clandestino; 10th Jul 2012 at 22:57.
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From the report:
The crew not taking into account the stall warning, which could have been due to:
- A failure to identify the aural warning, due to low exposure time in training to stall phenomena, stall warnings and buffet,
- The appearance at the beginning of the event of transient warnings that could be considered as spurious,
- The absence of any visual information to confirm the approach-to-stall after the loss of the limit speeds,
- The possible confusion with an overspeed situation in which buffet is also considered as a symptom,
- Flight Director indications that may led the crew to believe that their actions were appropriate, even though they were not,
- The difficulty in recognizing and understanding the implications of a reconfiguration in alternate law with no angle of attack protection.
- A failure to identify the aural warning, due to low exposure time in training to stall phenomena, stall warnings and buffet,
- The appearance at the beginning of the event of transient warnings that could be considered as spurious,
- The absence of any visual information to confirm the approach-to-stall after the loss of the limit speeds,
- The possible confusion with an overspeed situation in which buffet is also considered as a symptom,
- Flight Director indications that may led the crew to believe that their actions were appropriate, even though they were not,
- The difficulty in recognizing and understanding the implications of a reconfiguration in alternate law with no angle of attack protection.
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A simple question
What are the effects (in general) generated by descent from 37,000 feet to 0 feet in a time of 4 minutes on the ear drum (pressurizing system operating normally)
Personally (frequent traveler) I feel symptoms during descents or climbs (normal) of the aircraft
If there are symptoms .. is that this does not be also be an input (sensory) for pilots?
This could be as a source of concern in the cabin ? (Ref CVR multiple calls from a cabin attendant to cockpit)
What are the effects (in general) generated by descent from 37,000 feet to 0 feet in a time of 4 minutes on the ear drum (pressurizing system operating normally)
Personally (frequent traveler) I feel symptoms during descents or climbs (normal) of the aircraft
If there are symptoms .. is that this does not be also be an input (sensory) for pilots?
This could be as a source of concern in the cabin ? (Ref CVR multiple calls from a cabin attendant to cockpit)
Last edited by jcjeant; 10th Jul 2012 at 22:58.
Originally Posted by vovachan
Why was the AOA protection shut off? The computer continued to receive valid AOA info (which is not available to the pilot btw).
EDIT: I have to stand corrected on this; system is a bit simpler as FCCs don't crosscheck AoA vs speed, they just check whether both signals are valid, not consistent with each other. Inconsistency won't trigger law degradation, jut CHECK GW mesage on MCDU.
Life in a cockpit can get tough sometimes.
Last edited by Clandestino; 11th Jul 2012 at 05:13.
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- don't forget that those images were not what you would have seen on your shufti-scope - the colours are synthetically produced based on temperature I believe and we just do not know what would have been seen on their radars.
The rainbow of colors on the new radar, representing variations in rainfall rate, create a display which is easier to interpret than the older monochrome sets.
BLACK VERY LIGHT OR NO RETURNS Less than 0,7 mm/hr
GREEN LIGHT RETURNS 0,7 - 4 mm/hr
YELLOW MEDIUM RETURNS 4 - 12 mm/hr
RED STRONG RETURNS > 12 mm/hr
MAGENTA VERY STRONG RETURNS > 25 mm/hr
BLACK VERY LIGHT OR NO RETURNS Less than 0,7 mm/hr
GREEN LIGHT RETURNS 0,7 - 4 mm/hr
YELLOW MEDIUM RETURNS 4 - 12 mm/hr
RED STRONG RETURNS > 12 mm/hr
MAGENTA VERY STRONG RETURNS > 25 mm/hr
I once knew a guy who talked like a professional pilot in the cafeteria with endless stories of his adventures in Africa, but there always where holes in his stories. He was able to fool everyone for a long time and was adored by lots of guys and girls. No one really cared to blow his cover because he was in fact good company. Always called "The Captain". He had a PPL and worked as an ambulance driver. Reminds me of BOAC.
Last edited by svhar; 11th Jul 2012 at 01:48.
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Originally Posted by clandestino
Originally Posted by soylentgreen
If you don't have doctoral-level statistics knowledge and don't understand this, I'd be happy to explain in more detail?
Well, on the one hand, that's not appeal-to-authority precisely, since I was prepared to tell you why I disagreed (rather than just saying "Trust me, I'm a doctor"), but upon re-reading my words, they did come across snarky and like a cheap shot, so I apologize.
Originally Posted by clandestino
Originally Posted by soylentgreen
Care to explain your "Bad Science" comment?
Because it is based on monumental misunderstanding of aviation and human factors in it. Logically correct conclusion from false premises is still false!
Obviously, simulator-based research has a number of flaws, the biggest one (which you mention) is called Ecological Validity though I think that it could be argued that simulator research might present a lower bound on the %crash% estimate. The logic being that the pilots may suspect this is not a routine test, and they know they aren't going to actually die, may be less likely to panic, etc.
Again, I'm not familiar with this research, so I'm just speculating.
Originally Posted by clandestino
Originally Posted by soylentgreen
Or maybe in either case, we need to consider the human-machine interface as the thing that must change?
we should think of the big picture here, and improve the things that we do control.
Originally Posted by clandestino
Originally Posted by soylentgreen
Get 100 x 3-man crews, and put them in a multi-day full-experience simulator.
If you crash in the simulator, you can restart. Nonavailability of this feature in real life is very important factor when proverbial hits the fan and largely increases chance of inadequate response and panic.
If you crash in the simulator, you can restart. Nonavailability of this feature in real life is very important factor when proverbial hits the fan and largely increases chance of inadequate response and panic.
Originally Posted by clandestino
Originally Posted by soylentgreen
Fullt-time AOA sensors.
How many miles do we need google's robot cars to have accident-free before we trust them?
Seems like this technology (using LIDAR, GPS, and a bunch of other data) could be useful as a "third eye" autopilot that normally sits in the back and is quiet, but occasionally speaks up "Hey guys, uh, I know you are the bosses here, but we seem to be falling towards the sea in a strange attitude. I can show you on this 3D display just what I'm seeing..."
Originally Posted by clandestino
Originally Posted by soylentgreen
From this study, we calculate the ultimate data point: what % of crews survive. And perhaps more interestingly: what % of crews survive for the right reasons.
The "naturalistic" study shows that 1 of 37 crews in similar situations crashed. As I mentioned, that's such a small sample size that we can't say whether the actual percentage is closer to 0% or closer to 10%.
I hope that if the actual number is 10%, you'd agree with me that something is wrong, either with pilot training, or with the human-computer interface, yes?
My proposed simulator study would vastly increase the N to, say 100.
The statistics show that if 1/100 crashed, our confidence range narrows to roughly (0% to 3%).
If we had 1000 crews run through the simulator, and 1 crashed, then the interval shrinks further (about 0.5% to 1.5%).
Then, a naive analysis could be made (*with a ton of assumptions which we shall ignore*)
Let p1 be the % of flights on which the pitot tubes freeze and the autopilot drops out.
Let p2 be the % of times where the crew crashes when the autopilot drops out.
Then the overall risk of this = p1 * p2.
To me (again, not a pilot, but interested in cognitive psychology and statistics) both of these numbers are relevant here.
From what I know, the airline industry likes the risks to be in the one per million range or lower, and if there's a suggestion that it's anywhere near to 1% or 3% or even 10%, yikes!
... though the page ironbutt57 linked to is somewhat useful as it very often used for those still peddling the idea AF447 entered the storm.
Northwest 705 was high altitude upset that resulted in low altitude break-up
Who would have thought it is possible to make large longitudinal control displacement with yoke?
NLM 431 hit tornado, not something you meet at high levels. I can't find exact reference what was its altitude at the time but I don't expect that flight shorter than 100 km would climb very high.
Pulkovo 612 is example of trying to climb above ceiling in aeroplane that is prone to deep stalls. I couldn't find any reference to in-flight disintegration or any damage prior to ground contact in flat spin.
I cannot doubt Tim Vasquez's expertize on meteorology but filing these accidents under "high altitude weather-induced breakups" is quite a bit of stretch.
While AF447 operated in the area of storm activity, all the data collected so far point that the crew was aware of the severe weather and circumnavigated it successfully. "Don't fly into storm" is valid lesson yet it was heeded by the AF447 crew so you can't make them poster-children for it.
Originally Posted by Tim Vasquez
Some examples of weather-induced inflight breakups at higher altitudes are Northwest Flight 705 which was downed at FL250 in the Everglades in 1963; NLM Flight 431 which crashed in the Netherlands inside a thunderstorm; and Pulkovo Aviation Flight 612.
PROBABLE CAUSE: "The unfavourable interaction of severe vertical air drafts and large longitudinal control displacements resulting in a longitudinal "upset" from which a successful recovery was not made."
NLM 431 hit tornado, not something you meet at high levels. I can't find exact reference what was its altitude at the time but I don't expect that flight shorter than 100 km would climb very high.
Pulkovo 612 is example of trying to climb above ceiling in aeroplane that is prone to deep stalls. I couldn't find any reference to in-flight disintegration or any damage prior to ground contact in flat spin.
I cannot doubt Tim Vasquez's expertize on meteorology but filing these accidents under "high altitude weather-induced breakups" is quite a bit of stretch.
While AF447 operated in the area of storm activity, all the data collected so far point that the crew was aware of the severe weather and circumnavigated it successfully. "Don't fly into storm" is valid lesson yet it was heeded by the AF447 crew so you can't make them poster-children for it.
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That contradicts the BEA report. What is the source for this statement?
Also, it doesn't contradict the BEA: They state that with the - very limited - data they had available they couldn't conclude if the conditions were exceptional.
These images are totally useless. They only display what can be seen from above.
Even for instruments that can only see the cloud tops it is possible to use computer models to determine the internal structure of the cloud with a reasonable degree of success (better than a forecast could manage, for instance).
However this is irrelevant to the AF447 discussion, so if there's anything else to talk about then maybe it'd be appropriate to continue in a thread in jetblast.
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Clarification
Several questions..
At what point was the "deep stall" unrecoverable? What exactly is a deep stall? Was the trim issue the main obstacle to recovery? Thanks in advance.
At what point was the "deep stall" unrecoverable? What exactly is a deep stall? Was the trim issue the main obstacle to recovery? Thanks in advance.
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The Dominant Rule
Whatever you are flying, whenever and whatever the situation:
Proper Pilot selection, training and qualification will warrant safe, economical and predictable results. The rest are unimportant details.
Proper Pilot selection, training and qualification will warrant safe, economical and predictable results. The rest are unimportant details.
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Was the trim issue the main obstacle to recovery?
Since the stick was never pushed forward in an effort to unload the wing (reduce angle-of-attack thereby breaking the stall), it's hard to say...but having done an "amateur" reproduction of this event in a 320 simulator, I found it impossible to reduce the pitch below 12deg down, and the aircraft remained stalled, as the FPA was around 40deg....it required manual inputs to the stab trim in the nose down direction (as it had obediently driven to the full "nose up" position) to achieve the negative pitch down to reduce the angle-of-attack...keep in mind my experiment was from reading the report, not in the least bit a scientific-based simulator back-drive...
Since the stick was never pushed forward in an effort to unload the wing (reduce angle-of-attack thereby breaking the stall), it's hard to say...but having done an "amateur" reproduction of this event in a 320 simulator, I found it impossible to reduce the pitch below 12deg down, and the aircraft remained stalled, as the FPA was around 40deg....it required manual inputs to the stab trim in the nose down direction (as it had obediently driven to the full "nose up" position) to achieve the negative pitch down to reduce the angle-of-attack...keep in mind my experiment was from reading the report, not in the least bit a scientific-based simulator back-drive...
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ironbutt57,
For comparison to your experience, here is what PJ2 reported based on his SIM experience. It is in Post #165, Tech Log.
For comparison to your experience, here is what PJ2 reported based on his SIM experience. It is in Post #165, Tech Log.
Quote by PJ2: In the sim exercises, for recovery the SS was held full nose-down from the beginning of the stall warning at about FL360 until the wing was unstalled at about FL250, about 40 seconds total time, with a maximum achievable ND pitch of about -12 deg with an average of -10deg. The thrust levers were in the CLB detent and the THS was initially at 13.6deg and was returning to the normal cruise setting.
With the FPV symbol available, the FPA could be observed just above initially at -40deg, (pitch -10deg).
It began to move, initially very slowly up, about 15 seconds after full ND SS;
- at 29 seconds after full ND SS, the FPA had moved from -40deg, (pitch at -11) to -25deg, (same pitch);
- in the next 5 seconds it moved from -25 to -15, (FL257);
- at 38 seconds after full ND SS the FPA was -9deg, (pitch -5deg) with the wing unstalled and the CAS at 255kts.
With the FPV symbol available, the FPA could be observed just above initially at -40deg, (pitch -10deg).
It began to move, initially very slowly up, about 15 seconds after full ND SS;
- at 29 seconds after full ND SS, the FPA had moved from -40deg, (pitch at -11) to -25deg, (same pitch);
- in the next 5 seconds it moved from -25 to -15, (FL257);
- at 38 seconds after full ND SS the FPA was -9deg, (pitch -5deg) with the wing unstalled and the CAS at 255kts.
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Nose down side stick would have "corrected" the THS whether they recognized the setting or not. Recognizing that nose down was required was the issue.
The integrator never unwound over the rest of the flight (fall) to impact.
This was the reason for AP disconnect on AF 447 which subsequently led to the demise of the aircraft and all on board!
6: If I remember well some fuel had been transferred to the tail (which I suppose happens automatically during cruise, like on MD11, to reduce fuel consumption) making it even more hopeless, if they wanted and had tried, to exit the condition of deep stall they were in.
Is there a ready explanation for the very smooth line of THS increase to max, vice a more herky response to actual (commanded) pilot inputs? It looks graphically as though the THS was deploying to a "target" position, independent of pilot command?
The aircraft data say it more precisely than any statistics and sattelite imagery: The icing indicator never indicated anything, turbulences were only "light" by ICAO standards. So, "storm" wasn't a factor, as pointed out several times now. Except for creating an atmosphere where icing could happen to the pitot tubes without being indicated... but that is not limited to thunderstorms or the ITCZ. The flight path was choosen carefully right, at least one error they didn't make.
As to usage of pitot tubes: Mass flow sensors need an additional (second) temperature sensor. Which can fail. Heating can fail. The metering wire can rip while flying through hail. These failures are interrelated with AND, multiplying failure probabilities.
Pitot tubes indicate indicated airspeed (IAS), which takes air density automatically into account, by physics, not by processor. Quite convenient. GPS (ground) speed is no feasible backup - ever heard of upper winds, let alone jet streams that can make 100 knots difference? It's airspeed that makes an airplane fly, not ground speed. The difference is the wind, which hast to be measured. There you are again with air speed.
And there is sort of a backup sensor for the pitot tubes, which is the AOA sensor. You could hand fly the airplane without speed, just with AOA. But if even the stall warning gets ignored altogether...
angelorange, thanks to bring back the Airbus publication FAST #24. It is especially interesting to read CPT Wainwrights comment on the "fighter style" recovery actions that are proposed every now and then, as well as his warning to teach deep stall in the simulator, which could lead to completely wrong conclusions (the simulators do not simulate deep stall).
EDIT: For those that have not yet read, I like to quote the Airbus Chief Test Pilot in said article:
We manufacturers were very concerned over the types of manoeuvres being flown in simulators and the conclusions that were being drawn from them. Simulators, like any computer system, are only as good as the data that goes into them. [...] It should be obvious that firm conclusions about aircraft behaviour can only be drawn from the parts of the flight envelope that are based on hard data.
In fact, this is a perfectly adequate coverage to conduct all normal training needs. But it is insufficient to evaluate recovery techniques from loss of control incidents. Whereas, the training managers were all in the habit of demonstrating the handling characteristics beyond the stall; often telling their trainees that the rudder is far more effective than aileron and induces less drag and has no vices! In short, they were developing handling techniques from simulators that were outside their guaranteed domain. [...] It is worth saying that there was never any difference of opinion between the three test pilots on the group. [Airbus, Boeing, Bombardier]
In fact, this is a perfectly adequate coverage to conduct all normal training needs. But it is insufficient to evaluate recovery techniques from loss of control incidents. Whereas, the training managers were all in the habit of demonstrating the handling characteristics beyond the stall; often telling their trainees that the rudder is far more effective than aileron and induces less drag and has no vices! In short, they were developing handling techniques from simulators that were outside their guaranteed domain. [...] It is worth saying that there was never any difference of opinion between the three test pilots on the group. [Airbus, Boeing, Bombardier]
However, airplane upsets often will involve g load excursions and these cannot be duplicated within the simulator environment. They have not been designed for the purpose of replicating upsets, and as such, whenever maneuvering involves vertical or lateral loading, the realism degrades.
This is a very important point for both the trainee and the instructor. Instructional content must acknowledge this limitation and fortify instructional content based upon the trainee’s prior flight experience with g load excursions. Without this instructional input, a positive learning goal can be transformed into a negative learning experience. [...] However, flight data are not typically available for conditions where flight testing would be very hazardous.
This is a very important point for both the trainee and the instructor. Instructional content must acknowledge this limitation and fortify instructional content based upon the trainee’s prior flight experience with g load excursions. Without this instructional input, a positive learning goal can be transformed into a negative learning experience. [...] However, flight data are not typically available for conditions where flight testing would be very hazardous.
The AF447 crew's lack of CRM reminds me on an opposite case with Lufthansa on 20th March 2001, where the crew faced a major stick malfunction just after take off. Since they changed control immediately, everybody survived. In the mentioned incident (BFU report in German), the captain (PF) recognised that his actions were in vain and handed over... that saved the day. AF447 had several minutes to see that pulling the stick was in vain, not just seconds!
These are my main questions as to the crew's psychology: Why did nobody of FO or CP take control earlier, e. g. the captain request to sit in his chair and see for himself, and second why was the SO trying on his own for so long without requesting the others to take over? I'm sure I would ask for help / take over.
The only potentially explaining metal picture I have of the PF is that he was feeling very uncomfortable, in particular at this altitude which he considered to be too low (asked the CP to climb, but this was refused). He even wasn't familiar with St. Elmo's fire. Not the best precondition to master the next events. So the very first action after AP disconnect was to pull the stick.
The aircraft climbed accordingly. And the altitude increased unnoticed EDIT correction: without consequences. Why? What was the PNF doing? This is puzzling me just as much as why the PF was pulling all the time.
Last edited by TripleBravo; 11th Jul 2012 at 16:03.
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Hi,
Triplebravo
Not exactly ...
CVR extract:
PNF
2 h 10 min 31,2 Go back down
2 h 10 min 32,2
According to that
we’re going up
PNF
2 h 10 min 33,7
According to all
three you’re going
up so go back down
PF
2 h 10 min 35,2 okay
PNF
2 h 10 min 35,8 You’re at…
2 h 10 min 36,4 Go back down
PF
2 h 10 min 36,7
It’s going we’re
going (back) down
At this very moment the best action of PNF was to slap the PF in the face and take commands
Nothing of this happen
Triplebravo
The aircraft climbed accordingly. And the altitude increased unnoticed. Why? What was the PNF doing? This is puzzling me just as much as why the PF was pulling all the time.
CVR extract:
PNF
2 h 10 min 31,2 Go back down
2 h 10 min 32,2
According to that
we’re going up
PNF
2 h 10 min 33,7
According to all
three you’re going
up so go back down
PF
2 h 10 min 35,2 okay
PNF
2 h 10 min 35,8 You’re at…
2 h 10 min 36,4 Go back down
PF
2 h 10 min 36,7
It’s going we’re
going (back) down
At this very moment the best action of PNF was to slap the PF in the face and take commands
Nothing of this happen
Last edited by jcjeant; 11th Jul 2012 at 15:16.