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Comparing the 757-200 and the 737 Max10


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2 minutes ago, GeeBee said:

You don't train to look at the arrow? Really? That was drilled indelibly into my brain!

Boeing did not try to make the airplane like an Airbus, they tried to use a "little bit of Airbus". If Boeing had went full fly by wire, the stability would have been. built in and no MCAS would have been needed.

As for the Airbus pitch down issue, it shows the superiority of the Airbus triple redundant system vs Boeings single or even optional dual. By using three, you can "dual poll" safely and if there is still a problem, you have an out while still keeping the protections in place. There is a reason why the 75/76 has triple autopilots but Boeing does not extend that very good philosophy system wide. 

 

Actually any new aircraft boeing made / designed after 757/767 does have the triple system and they wanted to upgrade the 737 but SWA didn’t want that. They comprised and paid the price with the max. Same with A320 it’s locked in 80’s tech. The A350 is superior in everyway. Except for still pressurizing the cabin with the engines (should have gone the 787 route on that issue) which still can expose you to toxic fumes when an oil seal leaks but hey some TCP poisoning is not a big issue so they claim. 

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17 minutes ago, GeeBee said:

You don't train to look at the arrow? Really? That was drilled indelibly into my brain!

 

 

Yea just like it was for the pilots of AF447? 
they obviously either didn’t get the training or didn’t realized the consequences of retaking over the controls and they were AirFrance! Their training surely is more thorough than ours but maybe they have more of those below average pilots. <—that’s me being facetious in the last sentence.   
yes we trained for looking at the arrow but not when the other guy takes it right back and that’s why we now train in the sim exactly that and for guys that have experienced the retake over it’s no issue but for the new guy he doesn’t understand that he pressed the button and got the arrow but the aircraft is still not following what he is commanding. all of this could be avoided by tying the stick controls together but that’s not possible with fly by wire. Maybe put little servo motors that move the other stick in coordination with the primary so you can feel when the other guy has a death grip locked back control input and can deal with him instead of thinking there is something wrong with the computer. 

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22 minutes ago, Will.iam said:

Yea just like it was for the pilots of AF447? 
they obviously either didn’t get the training or didn’t realized the consequences of retaking over the controls and they were AirFrance! Their training surely is more thorough than ours but maybe they have more of those below average pilots. <—that’s me being facetious in the last sentence.   
yes we trained for looking at the arrow but not when the other guy takes it right back and that’s why we now train in the sim exactly that and for guys that have experienced the retake over it’s no issue but for the new guy he doesn’t understand that he pressed the button and got the arrow but the aircraft is still not following what he is commanding. all of this could be avoided by tying the stick controls together but that’s not possible with fly by wire. Maybe put little servo motors that move the other stick in coordination with the primary so you can feel when the other guy has a death grip locked back control input and can deal with him instead of thinking there is something wrong with the computer. 

Yes it is possible. What you are talking about is what Gulfstream has done with the G700, except they took it a step further and have full feel feedback as well.

 

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21 hours ago, Will.iam said:

Yea they were probably sleeping. And yes i never said Boeing would descend if the MCP was still at current altitude. The mistake i see Airbus pilots forgetting to press the knob to start a descent. Boeing you Never have to press the knob to start the descent see the difference. Would not be an issue if it didn’t happen to pilots getting distracted at that time to start down. Just one more thing boeing does better in my opinion. And this happens because you don’t usually get your clearance to descent at the TOD its usually 10 to 15 mins early and a cruise descent or how about pilot discretion descent i have received over an hour away internationally so yes we do set the MCP to a lower altitude sometimes over an hour before time to start down it’s nice boeing will start down airbus will not. 
speaking of other differences where are those known pitch and power settings they teach you when learning to fly the airbus? Ah they don’t. Boeing does different philosophies for sure but makes hand flown approaches much easier with known pitch and power setting memorized. 

So why do you believe that Airbus does not have known pitch and power settings?

 

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21 hours ago, Will.iam said:

 where are those known pitch and power settings they teach you when learning to fly the airbus? Ah they don’t. Boeing does different philosophies for sure but makes hand flown approaches much easier with known pitch and power setting memorized. 

They're in the QRH under "unreliable airspeed indication"... and a good training program will go through scenarios that have you use that and practice, as well as giving some easy pitch/power/altitude #s to use as a starting point.

I am newer to the bus and did not touch it until well after AF went into the drink, so I cannot comment on how the manuals were prior to that incident... but it is there now.

Edited by Immelman
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40 minutes ago, Mooneymite said:

Doesn't the 'bus have AOA constantly displayed?

Who needs airspeed indications?

No, it does not display AOA.

One new addition, post Air France, is the ability to display a pseudo-airspeed that is derived from AOA.  It also exchanges GPS altitude for baro altitude. This is in case of emergency, of course (the pitot tubes and/or static ports ice up or become unreliable).

If you Google “Airbus Back Up Speed Scale” you will get some interesting reading.  Pretty cool engineering, actually.

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Fly a couple trips and you'll know the pitch and power settings. Not rocket science.

As I said with regards to AF447, 2.5 + 83%. You will stay level and flyable.

Every pilot should be familiar with attitudes and power to fly their airplane. On light airplanes you never know when that rubber tube is going to break to the A/S indicator.

 

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Can anyone remember Air Florida into the Potomac ?

If they had known the numbers for FF and EGT on takeoff and cross checked them instead of just setting EPR it might have been a different outcome

I can't remember how many crews I trained that had no idea of those numbers in -200 737s but it was many. Many never looked at anything but EPR for the entire takeoff roll

As a sim instructor you could slip in many failures that many would never see until the engine rolled back even if the issue started well before V1.

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16 minutes ago, cliffy said:

Can anyone remember Air Florida into the Potomac ?

If they had known the numbers for FF and EGT on takeoff and cross checked them instead of just setting EPR it might have been a different outcome

I can't remember how many crews I trained that had no idea of those numbers in -200 737s but it was many. Many never looked at anything but EPR for the entire takeoff roll

As a sim instructor you could slip in many failures that many would never see until the engine rolled back even if the issue started well before V1.

Cliffy, wasn't the reversion just to N1 RPM?

The Air Florida 737-200 had 4 of the 5 engine instruments telling the truth, all they had to do was find the one liar.

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First you have to actually look at them

AND you don't fixate on just one gage (N1 or EPR)

Then you have to know what the "normal" N1, EGT, or FF is

Like I mentioned, I've trained many who had no idea other than the called out EPR

I was always a fuel flow guy. Take the 727, going down the ILS slope flaps 30 gear down it took 3,000 per engine to maintain the GS (+ or -)  If you lost one on approach (which they did in the sim) just go 4500 per engine on the 2 remaining and just stay on speed and slope. 

When I did my first right seat training in the 727 they gave me that exact scenario and I just went to 4500 per.

After we landed they (2 Check Airman) asked me how I found the right power so quick. They had no idea because they were RPM guys. 

If you ain't burning the fuel you don't have the power!

Edited by cliffy
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Just to add-

How many here even look at their OTHER gages once you open the throttle for T/O?

I have time to peruse the entire panel at least 2 times before 60 mph

I check RPM, MP, FF, Volts, Oil pressure and Temp each time.

Catch a problem before you're airborne. You'll live longer. 

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1 hour ago, cliffy said:

Just to add-

How many here even look at their OTHER gages once you open the throttle for T/O?

I have time to peruse the entire panel at least 2 times before 60 mph

I check RPM, MP, FF, Volts, Oil pressure and Temp each time.

Catch a problem before you're airborne. You'll live longer. 

Yep...... I was taught this during my initial flight training and I continue the process to this day.   Don’t like surprises (well, fun and good ones I do....:lol:)

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20 hours ago, Mooneymite said:

Doesn't the 'bus have AOA constantly displayed?

Who needs airspeed indications?

I don't know why, but the manufacturers seem to have a real disdain for AOA. We had to arm wrestle Boeing to finally include it in the NG. I remember well every pilot in the room telling Boeing we wanted it and they were telling us, why we didn't need it. I can't tell you how many times I had found the airplane "off weight" using AOA in the NG . As you remember there was a real "clean up" on AWABS at our line in large part from the discoveries from the NG's AOA. I would say Airbus' disdain is even higher even though they port the information to more places in the avionics suite.

Based upon that experience, I would say part of the disdain stems from the fact the manufacturers are afraid the airlines might become more conservative in their W&B routines than the manufacturers would like causing range/payload disenchantment.

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42 minutes ago, GeeBee said:

Based upon that experience, I would say part of the disdain stems from the fact the manufacturers are afraid the airlines might become more conservative in their W&B routines than the manufacturers would like causing range/payload disenchantment.

Absolutely!  When the L-1011 was introduced, it had a computer that sensed the weight on each gear and computed a real time weight and CG.  Absolutely ingenious!  Adjustments to the loads were required and the airlines very quickly declared the system "too expensive to maintain" and reverted to "standard weights".

No manufacturer has ever tried to introduce a new and cheaper to maintain system since. 

There's a reason for that, I'm sure.  :lol:

I'm sure every airline pilot gets to experience a takeoff roll that goes on far beyond the predicted takeoff distance...."standard weights"!

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21 hours ago, Andy95W said:

No, it does not display AOA.

One new addition, post Air France, is the ability to display a pseudo-airspeed that is derived from AOA.  It also exchanges GPS altitude for baro altitude. This is in case of emergency, of course (the pitot tubes and/or static ports ice up or become unreliable).

If you Google “Airbus Back Up Speed Scale” you will get some interesting reading.  Pretty cool engineering, actually.

In my opinion this is the way airpeed/Mach and AOA should be displayed 100% of the time..., but not sideways.  Can anyone turn the picture 90°?

20210117_164048.jpg

Edited by Mooneymite
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I remember one airline that did manual W&B in the cockpit at departure and they were allowed 1/2 weights to standard paxs for kids. Many a Capt opened the door and looked back and  said "I see 15 half weights" and miraculously they made it under MAX T/O weight allowed.   :-)

Midway became "sporty" on a hot summer day for them. 

The old 1011 system could be easily duplicated today with much more reliable, cheaper and accurate technology IF THEY WANTED TO DO IT

BUT no "fudge factor" room

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Since this has become a Boeing vs. Airbus discussion....

I was a Boeing guy for most of my career (767,777, 787) so I am most comfortable with Boeing's design philosophy, but I did accidentally spend a year on the A330. It was a great airplane, but a very different design philosophy from Boeing. Airbus engineers spend a great deal of time trying to think of every possible way a pilot could screw up and writing software to prevent those things from ever happening. Unfortunately, pilots being pilots, they will inevitably come up with a creative new way to screw up, and when they do so on an Airbus, they will have probably have absolutely no idea how they did it or how to fix it, Hence the famous joke about the difference between an old Airbus pilot and a new one. The new Airbus pilot says "what's it doing now?" while the old one says "oh look, it's doing that again". Boeing engineers took the approach that the pilot is inevitably going to screw up at some point, so lets make this thing simple enough that when they do screw up, they will know exactly what they did and can easily fix it. I have no experience with the 737, but the WB Boeings all fly like a great big C172. (That has its own problems with GenX, but let's not go down that rabbit hole)

All that being said, I don't honestly think that either manufacturer's design philosophy is better than the other. They are just two very different ways to approach the same problem and as a pilot, you just have to get your head around that philosophy and understand it.

One other thing I found amusing about Airbus design. For all the conscious effort they went to to remove the "feel", ie.  thrust levers don't move when the autothrust makes changes, sidestick inputs can't be felt by the other pilot, etc. They did decide to put this massive big trim wheel in the middle of the console of a fly-by-wire airplane that you never need to trim. What's up with that?

 

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35 minutes ago, GeeBee said:

The big trim wheel is so you can fly it in manual reversion. Did they train you on that?

Probably, but it’s been about 15 years, and I only flew it for a year, so it has been flushed a long time ago. That makes sense.

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The other reason it is large and in plain view is to inform the pilot the auto trim is activated since the airplane trims to streamline the elevator rather than the pilot trimming to pressure. It is one of the reaons why AF447 was unrecoverable out of FL270 as the stab trim had trimmed full nose up. 

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