Subject: B787 Info From A Ua Pilot

[Kip Powick]

I think that it would be 1.4megawatt vs gigawatt. I cannot believe that the two engines would be able to produce that much power. The 17 turbines from hover dam produce 2.08 gigawatts.

Boeing’s “more-electric” power architecture for the 787 will face special conditions to achieve airworthiness certification by the US FAA.

The extra certification requirements released today by the FAA require Boeing to prove that the 787 “is capable of recovering adequate primary electrical power generation for safe flight and landing” in the event of an in-flight power failure.

Boeing’s older airliners use pneumatic systems to power the hydraulics controlling flight control systems and landing gear, with comparatively small electric generators needed for onboard electronic systems.

But the 787 design omits the heavier pneumatic system in favor of electric power for the hydraulic actuators.

This change requires the aircraft’s two engines to drive four integrated drive generators providing 1.45MW of electricity, . The flight controls and landing gear depend on the electric generators as a primary power source.

The FAA recognizes the 787’s electric power as a potential safety concern that must be addressed by imposing special conditions beyond its normal airworthiness-proving requirements.

Boeing must show that the 787 is capable of safe flight with the engine and APUs inoperative. Alternate sources of power may include the battery, ram air turbine or a permanent magnet generating system.

The manufacturer also has to prove that the 787 has enough alternate sources of electrical power onboard to descend from the maximum operating altitude to the minimum altitude to attempt an engine and APU restart.

[JL]

CC or SS, regardless of which control input the aircraft is configured for, the ability to assimilate information when one begins to become cognitively over loaded will quickly overcome many defences built into the flight control design and avionics. That comparison is easily made with the DC8 ABX accident and the AF447 accident. It is my opinion that once you transition from overload situation and enter into a panic, all bets are off. The only hope is that both crew don't arrive there at the same time and that someone can take control and recover. Better yet, don't get there at all.

[Don Hudson]

seeker;

Re,

As Max said, Sorry about that, Chief.

Kip - regarding preferences, I honestly didn't have any. The SS was as easy to use as the CC and I liked both - they did the job. A lot more airplanes survived than were lost by both types of controls because it was the mind and "hands" behind the SS/CC that rescued the airplane, not the kind of control it was.

The one difference for the Airbus was, the autoflight system was engaged most of the time, which was the way the airplane was designed. And below 400', one was paying close attention anyway, SS or CC. I don't know what the philosophy is for the B787, but I'll bet airline managements aren't encouraging hand-flying given the price of fuel.

Mitch - you'll already know that I doubt whether a CC would have made a difference with the AF447 crew. The fact that the PF pulled up immediately without announcing the abnormality and the drill/checklist as per SOPs, and the fact that the PNF did not stop matters immediately and intervene with what should have been an obvious high-risk manoeuvre, (sustained 10deg NU at FL350, constant stall warning within 40 seconds) means to me that neither a control column nor an AoA indicator in the first 30 seconds, nor, post-apogee, the captain's ineffective questioning even upon viewing the rate-of-descent on the PFD would have altered the outcome. The pitch attitude of 15deg NU with a 20,000fpm descent rate was a strong indication that the aircraft was stalled and not in a high-speed situation, but, like both the Airborne Express DC8 and the Northwest B727, the crew was confused and continued to pull back on the controls, CC or SS. That says to me that they did not recognize the stall and did not know how to unstall and fly the wing. There are a host of similar LOC accidents in the past seven or eight years.

AF447 was recoverable even at FL100 yet the will and the training to do so was not there. Why not?

The argument isn't about CC or SS, it is about knowing one's airplane and being sufficiently trained and checked in SOPs, CRM and having sufficient presence of mind to remain in control of the airplane except where extraordinary circumstances mitigate against it. Here, there was no emergency which required immediate action yet it turned into a loss of control. Why?

I believe the crew likely did not know what they did not know and responded as best they thought, as we all would have. Thus the human factors aspect, including the examination of organizational factors of this accident have much to teach the industry and I hope the BEA spends the time to do it right.

Don

[Seeker]

Chicken. [baaak, buk, baaak....buk buk]

Well, I actually did have more to say but I was off to bed so I knew/hoped you or someone else would pick up the torch.

I pretty much agree with you and Kip - the CC is a bigger and more obvious clue than the SS so logically it should make it more likely that the GNF would notice this and react in some positive way. The problem however is that we are looking at the situation from a post-event frame of mind and not putting ourselves "in" the situation as we contemplate what happened. There is a certain amount of arrogance (myself included) that comes out in these discussions but really, at the heart of it, these guys had latched onto an "understanding" of the situation that was completely wrong and I doubt whether a CC would have made a difference to them. Now, whether it would make a difference to another crew on another day - who knows? How many airplanes have landed gear-up with a red light in the handle and the horn shrieking and after it's all over the pilot says, "I heard the horn and saw the light but didn't

understand". Surely it's impossible to miss the red light and loud horn - ahhh, no, it isn't.

[Kip Powick]

I believe the crew likely did not know what they did not know and responded as best they thought, as we all would have.

Ah, Don, I see by the "time-shot" on your last post it was 2:20am.....not sure where that is but it would be my local time here in "Dotland" and if your local time is close to that, no matter where you are, then I can understand why the above sentence may seem clear and understandable to you .....but not to me .

If the reference is to AF then I think it would be safe to say no one in the front end knew that they were stalled, had no perception of a stall, did not even know the indications of a stall, and in a near panic mode kept the aircraft stalled.

In this instance I find it hard to get my head around the part of the statement that says " as we all would have".

Perhaps in the far reaches, in a dusty corner, under a tattered blanket, there may be a moldy tidbit of basic aerodynamics that many pilots do not understood and perhaps due to ego.... failed to accept the fact that they are not well informed about said fact and failed to clarify the issue.......but a stall and the cockpit indications, day or night, are the most basic elements of knowing any aircraft._.

I have read and reread and reread your statement and I think I now understand what you posted..(my excuse - it's early here )...... ..basically........".ignorance is bliss and in a feeble attempt to instantly become 'unignorant', (if that is a word), in a critical aviation situation,...... one will resort to basic aerodynamic thoughts"...............in the AF case.. aircraft going down..... don't want that....point nose up......ergo SS pulled back.

No back to SS and CC.......As stated, the discussion is not about theorizing a different outcome to any accident based on SS or CC in the aircraft but rather why any pilot would prefer one installation over the other.

My preference is pretty clear ...as I have stated, but you have dodged the question..(due to your political forays?? ), Now com'on ......here is the scenario.........you just won xxx millions of dollars and you are having a personal aircraft built to your specs. Every builder in the world can install SS or CC but only one system in your dream plane......what's it gonna be????? (no waffling)

[J.O.]

You didn't ask me but my answer is an easy one - no waffling required - it would be the sidestick controller, provided that it functioned as part of the Airbus FBW system. I know it has its detractors but in my opinion it is a brilliant system, very effective and very safe. But then when I first was trained on it, I learned that flying near thunderstorms (or in any icing situation) meant that an unreliable speed scenario was possible, that I had to know the memory items (including maintaining current pitch and thrust at altitude) and be prepared to apply them.

[boestar]

IAm with Kip on the CC / Yoke. Reason it gives both Tactile feedback as well as visual position feedback from the aircraft where the SS just sits there in the middle no matter what the airplane is doing. Also the CC is visible to both pilots no matter what side where the SS is blocked possibly by the pilots body.

[mo32a]

Would it have been technically possible or feasible to put the SS on the other side so that it would be more visible to the PNF?

[Don Hudson]

Hi Kip -

My preference is pretty clear . . . what's it gonna be????? (no waffling)

Sidestick.

The CC and moving thrust levers are concessions to history. The SS is, as JO observes that the SS is a brilliant system and I completely agree - it is as natural as any control I've ever used in an aircraft. Clearly, it works for thousands of pilots over millions of hours and it works extremely well. I'm mildly surprised that Boeing didn't make the leap. Likely they just didn't want to be seen as copying Europe?

Don

[Don Hudson]

Hi mo32a;

Would it have been technically possible or feasible to put the SS on the other side so that it would be more visible to the PNF?

Technically? Absolutely. With digital controls almost any control and indication arrangement is possible. The thrust levers could have been dining-room dimmer sliders on the armrest. Now that would be something that would have merited some controversy.

[Thebean]

1.4 Gigawatts!!!

1.4 Gigawatts!!!

Where are we gonna find 1.4 Gigawatts??

Dilithium crystals?

[J.O.]

Who among our control column proponents has actually flown the Airbus sidestick operationally for at least a couple of years or more?

[conehead]

Technically? Absolutely. With digital controls almost any control and indication arrangement is possible. The thrust levers could have been dining-room dimmer sliders on the armrest. Now that would be something that would have merited some controversy.

Or even wireless.

[Kip Powick]

Who among our control column proponents has actually flown the Airbus sidestick operationally for at least a couple of years or more?

Well you got me there Jeff.. ..While in Toulouse France, I flew the Concorde SIM (Ram's horn CC), the A310 SIM- WD pilot course- (normal CC) and the A320 SIM (SS) and because of my background, preferred the A310. The Concorde Ram's Horn felt like I was on the end of a plow......back on the farm. The A310 was normal/good and of course the A320 was SS and I don't think an hour in the SIM is enough time to be adament that I "totally dislike" the SS......

My opinion about CC vs SS is purely based on my previous transport, (CV580/C130),experience and the fact that the GNF is instantly aware that there has been a control surface input by the GF...Perhaps it was more important to me to have that visual cue as I was a QFI/ICP on those birds and with students......well, I'm just say'n.

I seem to recall in the distant past that an A320 went in near Stuttgart and some 'aviation expert' did a case study and felt that perhaps the accident would not have happened had the GNF been aware of what the GF was doing with respect to control inputs..and I know......just another 'aviation expert's opinion' but most opinions are based on what one sees, reads and hears

And as you, and most others, know it's all water under the bridge out here in Dotland :Grin-Nod: ......

[Pivot]

Well I think we've beat this "stick" thing to death.

How about the new Lav in the 787? Do the pilots have their own or do they still need to mingle with everyone else?

[inchman]

Who among our control column proponents has actually flown the Airbus sidestick operationally for at least a couple of years or more?

I'm a CC proponent and flew the 320 for 9 years.

Yeah... it interferes with dinner and prevents providing pilots with a full keyboard, but multi-sensory inputs have proven, over the years, to be advantageous to situational awareness. Manufacturers have combined visual, auditory and tactile sensory inputs into helping pilots identify the current condition for decades. The position of the control column provides a visual and tactile reference for the position of the controls when a pilot may not think to look at the EICAS for control position as they try to figure out what's happening using the PFD.

The control column position answers the question "What's HE doing now?" (as opposed to the standard Airbus phrase "What's IT doing now?".)

[boestar]

The only thing I have against the SS is the complete lack of tactile and visual feedback to the pilot. If I am the PF and pull the stick back there is no indication to the PNF that I have done so other than the plane making the maneuvre requested. this leads to the questions? What is it doing or what are you doing? In the conventional Aircraft the PNF can see and feel the yoke moving and see the command inputs being made withoug looking at the PF.

I a situation like the AF accident it could well be that no one would think to look at the input on the SS because they are looking at the instruments trying to figure out what the "airplane" is doing. Honestly in a situation where you are trying to unravel a mystery it is not necessarily the easiest thing that is looked at first. Why are we falling from the Sky? Would the first question you ask be hey are you pulling back on the stick????? Probably not because you are busy looking at everything else and besides why would someone pull back on the stick in a stall? right?

As don says the SS is used in millions of flights by thousands of pilots and most like it and I understand why. What I would like to see is a study done to see the reactions as described above in both types with crews that had no idea what to expect and see if the CC provides information that is missing from the SS Cockpit. Would the reactions be different between the crews? would the resolution be found faster in one or the other?

Don: has this ever been done that you know of?

Passive communication is a powerful tool that we use everyday without knowing it. This is just one form.

[JL]

I think that most of the folks participating in this conversation of SS vs CC are misapplying the AF447 event as an example that SS is less intuitive/helpful in emergency situations. The fact that the flight crew were unable to recover is a clear indication that their cognitive abilities were vastly compromised; maybe even to the point of not being able to function at all. The CVR would be most telling if this were the case. Below is an excerpt from a lengthy review of studies that looked at cognition vs stress. The entire paper can be found here. Stress and Cognition: A Cognitive Psychological Perspective. The bottom line appears to be that when you reach a certain level of arousal/stress, any configuration of flight controls/instrumentation results in successful outcomes. Throw in high levels of stress which lead to a choking or panic situation and the arguments for which control system is better become meaningless. The unfortunate part of all of this, is that there is virtually no way to simulate panic for the purposes of flight deck design or training. The paper brings up skydiving as an example (maybe not the best) of poor performance under high levels of stress. A simple control, the pull chord on the reserve parachute, is not found in the hand of the deceased, rather, their hand is still on the chord of the primary parachute which failed to open.

Panic is a different stress state, and typically results in a more severe form of

performance degradation than choking. When panic occurs, behavior becomes

primitive; if the person thinks at all, it is maladaptive automatic thinking (Katz &

Epstein, 1991). Panic is not just a matter of reverting to behaviors that had been

learned earlier or to memory representations in an explicit form. Panic is

characterized by an even more rudimentary, instinctive kind of behavior aimed at

survival. Rather than “overthinking” the situation, a panicked person stops

thinking altogether and is inclined to react in the most basic way to get out of the

situation or to escape the stressor. Stress appears to cause explicit memories to

become unavailable or irretrievable. In a panic state, short-term memory seems to

cease functioning. The person just freezes, that is, fails to respond, responds in an

automatic but unskilled way, or reverts to primal instincts . Moreover, high

arousal, as under stress, results in perceptual narrowing (Easterbrook, 1959). The

range of cues or sources of informational input that an organism might use to

escape the situation is reduced. The panicked individual focuses, indeed often

obsesses on one aspect of the environment, usually to the neglect of information

that could eliminate the stressful condition. The consequence is that, even though

the goal is survival, performance is functionally maladaptive (Katz, & Epstein,

1991). To use another bit of sports jargon, coaches have been known to refer to a

state of panic as “brain lock.” The cognitive performance system is locked down.

[J.O.]

That is exactly my point, JL. No one on either side of this little debate has faced a scenario like the one the AF447 crew faced. Yes much of it was of their own doing but whether we accept it or not, what they did made sense to them at the time. Once they got into the coffin corner of not understanding what was really happening, they ended up in a state of cognitive tunnel vision and were powerless to do anything about it. Short of being in an airplane that would either tell them exactly what to do or take over and do the recovery itself, I doubt that anything would have changed it.

[Kip Powick]

Just to clarify, I am not advocating that a CC would have saved AF447...in my opinion, the entire front end had no idea what had happened to the aircraft, (stall). Heck, there is even the possibility that if the aircraft had had a CC they would have held it full back in an attempt to recover.....the demise of AF447 was most likely due to the fact that none of the pilots recognized that they had "stalled" the aircraft.

[blues deville]

Who among our control column proponents has actually flown the Airbus sidestick operationally for at least a couple of years or more?

I had the pleasure of flying A320's for nearly two years. I initially did the transition kicking and screaming but once I accepted the differences Airbus offered, it was enjoyable to fly. The biggest adjustment for me I was the lack of 'feel'. The 'eye/hand' coordination required to rotate a large aircraft no longer included the weight feeling in the controls. However, once the sim training was complete I was just as comfortable with the FBW and SS as with any previous conventional type.

I now fly a full FBW/CC aircraft with lots of gadgets to make anyone (including me) look good.

[boestar]

I am with kip, I used the LIKE word as to the situation.

My point being that in a similar incident had a pilot walked into the cockpit without knowing anything else, a CC would indicate what the aircraft was being told to do where a SS just sits in the middle with no visual/tactile feedback. Walking into a cockpit and seeing the CC full aft with a non existent airspeed would kick me in the face as to what was going on, i would then look for confirmation anywhere possible. Walk into an airbus and your only indication is fluctuating instruments and a decaying altitude with no indication of what the aircraft is being asked to do.

[Don Hudson]

J.O.

Once they got into the coffin corner of not understanding what was really happening, they ended up in a state of cognitive tunnel vision and were powerless to do anything about it. Short of being in an airplane that would either tell them exactly what to do or take over and do the recovery itself, I doubt that anything would have changed it.

There is some aeronautical engineering data from an extremely good source that indicates that, although requiring attitudes which line crews would not be comfortable with at low altitudes, the aircraft could have been recovered as late as 6000'.

Some explanation of the graph is in order:

The graph plots CAS against Flight Path Altitude. There is no time element in the graph. The bottom (x) axis is CAS, the side, (y) axis is Altitude in ft.

The yellow line is the flight path CAS derived from an exhaustive re-analysis of the DFDR data in the BEA Third Interim Report.

The purple line is CAS. The CAS starts out at roughly 275kts, slightly increases then rapidly drops to about 120kts (purple line moving to the left, still at FL350). We can also see the rapid, initial climb against the loss of airspeed. Times are indicated in blue and begin at 02:10:00, the time of the UAS event.

The purple line then shows increases/decreases in the actual CAS as the aircraft descends.

The black solid line is the Vs1g stall CAS.

The black dashed line is the Vs2.5g.

The black dotted lines show Mach Number.

The group of lines extending to the right, off the actual CAS (purple) line, represent increases in the CAS in 3 recovery scenarios which involve pitching the aircraft down to reduce the AoA and unstall the wing.

The first set of three lines extends to the right at FL350, the next group at FL200 and the last line at about 6000ft.

Each of the three lines indicates potential recovery (unstalling the wing) at various rates-of-change of the AoA and pitch attitude.

The first set at FL350 indicates the nature of the recovery (in terms of altitude lost as speed is gained and AoA is reduced), when the aircraft is pitched down to 10deg and the AoA reduction (from a nominal 35+ deg), of 3, 2, and 1 degree per second.

The second set at FL200 indicates the nature of the recovery at 20deg ND pitch, 10deg ND pitch and 5deg ND pitch, with a reduction in AoA of 2deg/sec.

The third, I am assured, is doable, but the author of this data does not expect that a line crew would pitch the aircraft to 10deg ND at 6000' with a descent rate of 10,000+ fpm down. But, he says, it can be done.

The extended lines have three components - red, yellow and blue.

The red portion of each line indicates that the wing is still stalled even as CAS increases.

The yellow portion is the recovery portion as AoA reduces from a stalled to an unstalled wing.

The blue portion indicates the "run-out"...the continued descent and increased speed as the aircraft is leveled off while avoiding the secondary stall.

Off-topic?

This is off-topic in one way, but very much on-topic in another way. It indicates that perhaps not enough is known and understood or even taught in ground school and recurrent training, regarding high altitude, high Mach No., swept-wing aerodynamics and in particular, the dynamics of the stall of these kinds of aircraft.

The argument for teaching/learning more about these areas is in the trended data where over the past eight years or so, almost a dozen transport category aircraft accidents, many fatal, have occurred when crews have stalled and lost control of their aircraft.

My understanding of jet transport flight came almost exclusively from D.P. Davies and my own self-directed study after I joined the airline. I thought jet transports stalled at AoAs of 12 to 15deg. They do, but Davies only discussed the approach case, when all the high-lift devices were out, (1972).

I did not know, until AF447 and detailed discussions with two aeronautical engineers regarding a deeper understanding of Mach effect that our transport aircraft are always about 1 to 3 degrees above the stall AoA in cruise. The important corollary to this fact is, of course, that changing AoAs at very high Mach numbers is very difficult. The rapid loss of energy/airspeed as a result of the instant pull-up in the AF447 accident brought the Mach down to the point where the Mach number stall AoA and the actual AoA met, and the aircraft stalled...within about 30 seconds of the initial event.

I think these are important understandings about one's aircraft. Has anyone here ever been exposed to these notions in ground school or recurrent sim training? Heck, I never once had a UAS abnormal in 35 years of recurrent training or even a discussion about it.

[Don Hudson]

Boestar - I'm not aware of any studies, nor would I expect any to be at the "front lines" of academic or engineering discussion given the success of the SS concept and design. Where one might expect it is in the BEA Final Report, which is "event specific". I wouldn't, for example, expect the design to be among any recommendations for change.

I believe this because all previous and present documents and SOPs concerning the recognition of and response to the stall do not include either SS or CC position even though the arguments may have some anectdotal validity.

Among the listed, standard primary indications of the stall are a very high descent rate which cannot be arrested regardless of pitch or control input. From the apogee, and when the captain entered the cockpit until impact, this indication* was absolutely clear on both PFDs and the ISIS, all of which had IVSI and altitude information. To give an idea of the rate, on a round-dial steam altimeter the needle would be going around the dial about every three seconds. The pitch was mostly 15deg NU, the IVSI about 20,000fpm at its highest.

The sim takes full, forward SS to achieve 10deg ND. The THS slowly winds back from 13deg NU, the FPV slowly creeps up the PFD from the bottom, at 35deg, to about 10deg which about matches the pitch attitude, and the wing unstalls. It takes about 40 seconds and between 12 and 15 thousand feet starting at FL350. Because the air is thicker, this altitude loss is much less at lower altitudes.

Don

*the IVSI is both IRS and barometrically-driven, so is reliable with U/S ADRs.

[hollywud]

Richard, look what you've started! A little comment about having a table in the cockpit and the Airbus vs. Boeing crowd pounce. It happens every time. Opinions aside (because after all it's only opinions being expressed here), if yokes were really superior, I wonder why the Space Shuttle designers opted for the side-stick? Just curious............