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jb747 you have been quite critical of Airbus's approach to "dumbing down" the pilot/aircraft interaction by putting some much control into the aircraft systems. This is by comparison to your previous experience (747/767). I was wondering if in pilot circles there is any discussion of the 787 and whether Boeing have followed Airbus's approach or have continued to follow their own approach which you favour.

I was just prompted looking at the new photos of the ANA 787 to wonder whether this revolutionary new aircraft was revolutionary just in construction or revolutionary from the ground up.
 
jb747 you have been quite critical of Airbus's approach to "dumbing down" the pilot/aircraft interaction by putting some much control into the aircraft systems. This is by comparison to your previous experience (747/767). I was wondering if in pilot circles there is any discussion of the 787 and whether Boeing have followed Airbus's approach or have continued to follow their own approach which you favour.

I was just prompted looking at the new photos of the ANA 787 to wonder whether this revolutionary new aircraft was revolutionary just in construction or revolutionary from the ground up.

Remember that Boeing have done a FBW airliner before...the 777, and the only discussion of that aircraft in pilot circles is invariably positive.

Airbus have not necessarily put more control into the aircraft systems. For instance the A380 fuel system is fully automated. Nevertheless, it behaves in a very similar manner to that in the 747-400. The only reason for the full time automation there is because it is constantly pumping small amounts of fuel around, and pilots would very quickly become tired of that game. It's really much the same with most of the subsystems. The only point of real divergence is the interface with the pilots....

Note that the 777/787 still use what most people would call 'old fashioned' control columns, when they could just as easily use sidesticks. So, why did Boeing forgo the smaller, lighter, option? It isn't as if it takes most pilots long to become used to it, nor are the columns needed any more to allow the pilots to apply greater force to the controls. Perhaps the answer is that joysticks provide NO feedback to either the pilot flying, or to the non flying pilot. In a 767/747 any attempt by an FO to over rotate could be easily countered, simply by limiting how far you allowed the control column to come aft. You didn't have to 'take over'. Nor did you have to push a button (where is it) in the scant moments you had available to allow you to take the controls. If one looks at AF447, you have to ask if it would have continued its plunge (!) if either of the pilots not flying had any idea that the PF was holding full backstick. Without leaning forward and actually looking at the other pilot's control, there is no way to tell.

It's much the same with the thrust levers. When in manual mode, they work like any other aircraft. BUT, you can certainly tell that they don't want you using them that way, because the controls are very unbalanced when you do. Basically that means that the joystick is close to you, and is very light, whilst the thrust levers are a long reach, and quite heavy. But, at the same time they are quite sensitive, which means that they are difficult to manage smoothly. They can be quite non intuitive. For instance, if you were to need more power just after take off, pushing them to the TOGA detent would give you what you expect. But, in many cases of derated takeoffs, pulling them back to the CLB detent would also give an appreciable increase in power. In Boeing, the thrust response is always in the direction the levers are pulled/pushed.

Failures. The aircraft does not respond to some failures at all gracefully. For instance, if you lose two air data computers (of the three), one pilot will lose all of his data. The system allows either of the pilots to select their displays to the third, but it will not allow BOTH pilots to select the same source. A Boeing will....but it will give you an EICAS warning if you do select the same system. (QF30 ended up on a single source.) And, just to make it more fun, the next consequence of that failure is that the autopilots, auto thrust and flight directors will also cease working. The aircraft also drops to alternate law II. And because there is no aileron trim available to the pilots, the aircraft will almost certainly be grossly out of lateral trim (which has the effect of making it even harder to fly). So, we're going to take most of the data needed to fly from one of the pilots, and simultaneously make the aircraft much harder to fly for the other. I'm really at a loss to understand why Airbus have this 'thing' about taking the flight director away as soon as there is almost any form of failure. Losing it in a Boeing is pretty much unheard of.

The upshot of all of this is that the aircraft can go from being quite easy to fly, to being extremely hard, as a consequence of relatively minor failures. Obviously, many of the design decisions were made by engineers (with virtually no consultation with pilots), and with an overriding belief that 'it will not happen'. Not only will 'it' happen, but it will happen way sooner than they think.

Another issue is something that's akin to what seems to exist around Apple computers. Fan boys. I have no issue will people who like the Airbus way of doing things, but, they sadly also assume a dismissive attitude to anyone who is at all critical of AB. If they are being nice, you'll be told that you need to 'embrace the Airbus philosophy'...almost as if it is a religion. If less nice, you'll be told that you are a Boeing 'holdout'.

And on your original question...I think that any pilot of ANY previous Boeing aircraft would feel immediately at home in a 787.

Actually, something else that drives me nuts about the Airbus....ergonomics. In the lead in blurb in the manuals it says that the coughpit is designed to be clean and uncluttered. What this actually translates to is rows of IDENTICAL switches, with dramatically different functions. Boeing overhead panels tend to look like a bit of a hodge podge because many different switch designs are used, and their alignments and colours are also varied. AB, on the other hand will give you switches that are identical in all but function, within inches of each other. Good example is the passenger oxygen, and the emergency electrical configuration....a pair that it's best to get the right one if you ever need either.
 
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On aircraft which use a tiller for steering on the ground, I would be right in thinking that if the tiller is on the left side (pilots side) the pilot steers right by pushing forwards and left by pulling back? Am I also right in assuming that where a tiller is fitted for the co-pilot its operations are in reverse (push forwards for left, pull back for right)?

Also on Boeings, how sensitive is the yoke? Does every mm of movement cause a major affect on a plane, or does a pilot need to move the yoke a fair bit before there is any noticeable affect?
 
On aircraft which use a tiller for steering on the ground, I would be right in thinking that if the tiller is on the left side (pilots side) the pilot steers right by pushing forwards and left by pulling back? Am I also right in assuming that where a tiller is fitted for the co-pilot its operations are in reverse (push forwards for left, pull back for right)?
Spot on. Feels quite natural. The inputs are quite linear, with both this and the 767 system. The Airbus is not, and again the two controls are not interconnected, so you need to be very mindful of just where the nose gear is pointed any time you take over whilst taxying.

Also on Boeings, how sensitive is the yoke? Does every mm of movement cause a major affect on a plane, or does a pilot need to move the yoke a fair bit before there is any noticeable affect?
Because the 767/747 are not FBW, the amount of motion required varies with the speed and configuration. Normally not much motion in pitch, other than when rotating for takeoff, and flaring for landing. Roll inputs can vary a lot, and may be quite large when countering any wind near the ground. Unlike autopilots, which are progressively reduced in authority as an aircraft nears the ground, pilots tend to use larger, and more rapid, inputs near the ground.
 
Actually, something else that drives me nuts about the Airbus....ergonomics. In the lead in blurb in the manuals it says that the coughpit is designed to be clean and uncluttered. What this actually translates to is rows of IDENTICAL switches, with dramatically different functions. Boeing overhead panels tend to look like a bit of a hodge podge because many different switch designs are used, and their alignments and colours are also varied. AB, on the other hand will give you switches that are identical in all but function, within inches of each other. Good example is the passenger oxygen, and the emergency electrical configuration....a pair that it's best to get the right one if you ever need either.
Reading this brought a smile to my face - about ten years ago a good friend of mine who was a Qantas B747 first officer (he's a Qantas B737 captain last I heard) had a very large aquarium in his house. While he was away on a trip to London or somewhere I answered a frantic SOS from his wife to go and see if I could rescue his aquarium as things had gone out of whack and fish were dying etc. When I got there I discovered that all of the electrical cords for the pumps, lights, filters etc all passed through a hole in the wall behind the tank. So I headed around the back to find that there was this mass of nearly 20 black cords coming through the wall - and none of the damn cords were labelled! It took over an hour of stuffing around to eventually find out which cable it was that powered the filter that had stopped working.

When he got back the conversation went something like "mate I don't know much about flying planes, but I'm guessing that every switch and knob in your Boeing 747 coughpit is labelled - please do the same for all of your cords on your fish tank!":D He did see my point.

JB747 has probably flown with him as he was also from Melbourne.
 
I had an interesting one the otherday... flying BNE - DRW (on VA not QF) and the pilot left the seatbelt sign on for about an hour and a half....

JB do pilots have that on the list or something? or is it something your prompted to do, or the like?

I could understand if thier was rough weather, but there was no more than normal during take off and smooth as a babys behind for the rest of the trip (except for a hell of a landing in DRW).

I could see the FA's were getting annoyed they weren't able to get up - eventually the CSM picked up the phone and called through to the pilot (or i assume) because 2 seconds later it was off and there was a mad dash to the toilets!!

Ironically, its times like these I wish that I had an ACTUAL book and not the book i was reading on my iPad....

Cheers

Simsy
 
I had an interesting one the otherday... flying BNE - DRW (on VA not QF) and the pilot left the seatbelt sign on for about an hour and a half....

JB do pilots have that on the list or something? or is it something your prompted to do, or the like?

I could understand if thier was rough weather, but there was no more than normal during take off and smooth as a babys behind for the rest of the trip (except for a hell of a landing in DRW).
Seat belt signs are something that are on the approach end of the checklists, but not the other. There are lots of reasons for leaving it on after take off. Sometimes the radar is showing lots of weather, whilst at others, you may have reported turbulence, or even simply be climbing into a very strong jet stream.

In the cruise, the signs are normally put on, not so much because we are in turbulence, but because we're using the radar to duck and weave around storm cells. Nine times out of ten we do so without any bumps at all, but on that tenth one there can be substantial turbulence without any warning at all....if the signs weren't already on, it would be way too late.

In most of the jets there is an 'auto' setting for the seat belts. That will select them on whenever the flaps are out of up, or the gear is selected down. We leave it in auto as a backup, but manually select it on when refuelling is complete, and then off when we are happy that it will remain smooth. On approach, I normally select it on at about 20 miles to run (the auto selection would do it about 5 miles later).

I could see the FA's were getting annoyed they weren't able to get up - eventually the CSM picked up the phone and called through to the pilot (or i assume) because 2 seconds later it was off and there was a mad dash to the toilets!!
In my experience they tend to ring pretty quickly...if they either want the sign on, or off.
 
I had an interesting one the otherday... flying BNE - DRW (on VA not QF) and the pilot left the seatbelt sign on for about an hour and a half....

Simsy

happened once on CX who are normally quite frugal with such notifications. I asked the FA to check with the pilot if this was really necessary, it had been smooth for 20 minutes, and it came off straight away.

I guess sometimes there will be breakdowns between humans and buttons....but it is rare.
 
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I've just been reading about a LOT 767 that did a belly landing in Warsaw. Everyone was safe so that's great.

Assuming that they repair the aircraft, who signs off on the bottom line that its OK to fly? Someone from Boeing? And do they test fly the bird before putting passengers on it?

I guess the same applies to any major repair like QF32 stuck in SIN.
 
I've just been reading about a LOT 767 that did a belly landing in Warsaw. Everyone was safe so that's great.

A follow up to this question, what kind of damage would you expect to see to the runway? I'm wondering how extensive the repairs will need to be before it's usable again and what kind of tests need to be carried out "post repairs" to ensure the runway is fit for use again
 
Welcome to AFF jaseblenner. I believe this is the landing to which you are referring...

LOT landing

Story here.

I'd have thought there is more than a little bit of panel repair and a paint touch up. Although there wasn't a tail strike on the ground and it looks like he kept the nose up at the correct angle. Good flying.

I still don't understand why they didn't manually put the landing gear down. A pilot friend of mine said:
They would have tried the manual release and also the 'make the plane go up and down violently to get the bloody things to move' manoeuvre. I'm guessing the hydraulics lock some or all of the gear up somehow
jb747, does that sound right.
 
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And in keeping with the questions re the belly landing.

When a major incident like this occurs and the cause is determined, do you have to, are you allowed to, practise it on the simulator?
 
I've just been reading about a LOT 767 that did a belly landing in Warsaw. Everyone was safe so that's great.

Assuming that they repair the aircraft, who signs off on the bottom line that its OK to fly? Someone from Boeing? And do they test fly the bird before putting passengers on it?

I guess the same applies to any major repair like QF32 stuck in SIN.

Major structural repairs would be done by the manufacturer, with ancillary work done by the owner's engineers. Test flying at the end will most likely be done by the owners. There will certainly be a test flight program before any passengers get near it again. In the case of QF30, the initial acceptance test flight program was repeated before the aircraft left Manila. QF32 will most likely have both an Airbus designed program, plus the acceptance tests.

A follow up to this question, what kind of damage would you expect to see to the runway? I'm wondering how extensive the repairs will need to be before it's usable again and what kind of tests need to be carried out "post repairs" to ensure the runway is fit for use again

I wouldn't expect much damage to the runway at all...if any. Emirates didn't do any harm to Melbourne.

I'd have thought there is more than a little bit of panel repair and a paint touch up. Although there wasn't a tail strike on the ground and it looks like he kept the nose up at the correct angle. Good flying.
Once it settled onto the runway, I doubt that he had a great deal of control of the pitch attitude at all.

I still don't understand why they didn't manually put the landing gear down. A pilot friend of mine said:

They would have tried the manual release and also the 'make the plane go up and down violently to get the bloody things to move' manoeuvre. I'm guessing the hydraulics lock some or all of the gear up somehow
We actually don't know what the problem was. The 767 has a quite simple gear system. There is only one hydraulic system involved. Once in flight, the system pressure is removed from the gear, and it just sits on the gear doors. In an alternate extension (there is no such thing as a manual release), the gear door locks are electrically opened, and the gear simply falls to the open position. The gear doors remain open. G loadings will have little effect if the doors don't open..and in any event we have no idea what was tried/not tried.

And in keeping with the questions re the belly landing.

When a major incident like this occurs and the cause is determined, do you have to, are you allowed to, practise it on the simulator?
Things that happen around the world, that are seen to have some training value, normally appear in programs quite quickly. Some things are of limited value, and I really don't see much value in practicing a gear up landing. Working the system to avoid it in the first place is much more worthwhile.

In the video, all of the gear doors appear to be closed. That means that an alternate extension was either not tried, didn't work at all, or, perhaps it was tried, didn't rectify the problem and so the gear was reselected to up (which would close the doors). So, the question to ask, relates to the initial problem. Did all of the gear not extend, or was it a partial failure?

Ops manual quote re gear extension:
Landing Gear Extension
When the landing gear lever is moved to DN, the landing gear doors open, the gearare unlocked, and the GEAR and DOORS lights illuminate.
The gear are hydraulically powered to the down and locked position. Thedownlocks are powered to the locked position, all hydraulically actuated geardoors close, and the main gear trucks hydraulically tilt to the flight position. Whenall gear are down and locked, the gear down lights illuminate and the GEAR andDOORS lights extinguish.
The amber GEAR light remains illuminated and the EICAS caution messagesGEAR DISAGREE, L or R SIDE BRACE, L or R DRAG BRACE displays if anygear is not locked down after the normal transit time. The extinguished green geardown light indicates the affected gear. The DOORS light remains illuminated andthe EICAS advisory message GEAR DOORS displays if any hydraulicallyactuated door is not closed after the normal transit time.
Landing Gear Alternate Extension
The alternate landing gear extension system uses an electric motor to trip thelocking mechanism for each gear. Selecting DN on the ALTN GEAR EXTENDswitch releases all door and gear uplocks. The landing gear free fall to the downand locked position.
When all gear are down and locked, the gear down lights illuminate and the GEARlight extinguishes. During alternate extension, the DOORS light remainsilluminated and the EICAS advisory message GEAR DOORS displays because allthe hydraulically powered gear doors remain open.
 
jb747, thank you for your explanation.

jb747 said:
We actually don't know what the problem was. The 767 has a quite simple gear system. There is only one hydraulic system involved. Once in flight, the system pressure is removed from the gear, and it just sits on the gear doors. In an alternate extension (there is no such thing as a manual release), the gear door locks are electrically opened, and the gear simply falls to the open position. The gear doors remain open. G loadings will have little effect if the doors don't open..and in any event we have no idea what was tried/not tried.
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In the video, all of the gear doors appear to be closed. That means that an alternate extension was either not tried, didn't work at all, or, perhaps it was tried, didn't rectify the problem and so the gear was reselected to up (which would close the doors). So, the question to ask, relates to the initial problem. Did all of the gear not extend, or was it a partial failure?

The quotes from the story I referenced above:

LOT said the plane suffered "a central hydraulic system failure," indicating that the hydraulics used to extend the landing gear, or undercarriage, failed. The failure of an entire undercarriage was unprecedented for a Boeing 767 and highly unusual overall, according to aviation data and experts.

The pilots discovered there was a problem about half an hour after leaving Newark, said LOT president Marcin Pirog. They circled the plane above the airport for about one hour before descending, partly to keep trying to release the landing gear, and partly to use up fuel to lessen the risk of a blaze.
And
LOT, Poland's national flag carrier, said that Wrona was one of its most experienced pilots and had been flying Boeings for 20 years. He is also experienced in flying gliders, and some media reports suggested that may have helped him make such a successful emergency landing.
then finally
The undercarriage of the Boeing 767 is made up of three parts, one under the nose and one below each of two wings. According to data from the Aviation Safety Network, there has never been such an incident involving the failure of the entire undercarriage on a Boeing 767.

Patrick Smith, a Boston-based pilot who flies the Boeing 767 for a major US airline, said something "very mysterious" must have occurred.

"Something pretty high up in the architecture of the landing system must have happened for all three gears not to come down," Smith said. "Something that was obviously common to all three gears."
Will be interesting to hear the outcome from the forthcoming report.
 
Also, how does the size of the plane affect this? I.E. would an A380/747 be able to do a belly landing?
It's difficult to come up with a scenario that gives the need. The 747 and 380 split the hydraulics and electrics that are involved in operating various parts of the gear. Total failures of those systems should only result in the loss of their part of the overall system...in other words, much of the gear should always go down. Landing, for instance, with an individual wing or body gear retracted shouldn't be a problem at all. Much the same for a symmetrical pair (both wing for instance). And, of course, alternate gear extension systems also exist on both aircraft.

Aircraft that have very high approach attitudes (i.e. the Mirage) would be the most problematic. You really don't want to hit tail first. Many a military aircraft has landed on drop tanks, with no damage to the aircraft beyond (the already expendable) tanks.

A little reading on what is normally a totally unreliable (!) source (PPRUNE) indicates that the aircraft lost the C hydraulic system not long after take off. Various people who fly Microsoft flight simulator then go on to wonder about the logic of flying across the pond with that system out. Well, basically it does pretty well nothing in the cruise...so you're faced with a C system out landing no matter where you go. There is no reason to turn around and land in a hurry. For the alternate gear extension to then fail as well....it's unusual to say the least.
 
Alternate/emergency/reserve systems spend their lives just sitting there, waiting for the day that they'll be used. They will occasionally get some exercise, when a maintenance procedure calls for it, but, day to day, you don't really know whether they will work or not. I wonder if the alternate system on this aircraft had actually been u/s for a while..it's just that nobody knew until the C hydraulic failure called for it to be used. One obvious common point is the single switch (and presumably wiring) that operates the alternate extension.

Bit like ejections seat...you don't know that they'll fire when you need it, but you certainly can't go pulling the handle every now and then just to check.

And what is this gibberish in the media about being a glider pilot. So what? It wasn't a glide approach. The engines, and I'm sure all other systems, worked just fine.
 
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...
And what is this gibberish in the media about being a glider pilot. So what? It wasn't a glide approach. The engines, and I'm sure all other systems, worked just fine.
Probably trying it on to link with Sullenberger gliding an A320 into the Hudson river. (Although that guy is an extremely experienced aviator - Gliding or no Gliding).
 
Interesting discussion here, thanks for the input jb747 and others.

I have a question that was alluded to early in the thread (not that I've read every single page) and it relates to airline pilots flying for fun / pleasure. Obviously everyone is different but is it fairly typical for an airline pilot to have no interest in flying outside of work or after retirement? Does the job just get too mundane after a while or something? I might have it wrong but this is the impression I've got after talking to a handful.
 

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