30 minutes ago, Bobsk8 said:

Both Airbus and Boeing are working on pilot less aircraft. The one of the  largest expenses in aviation are pilots salaries. Currently the pilot for the most part, flies the aircraft up to about 600 feet , AP on, and from then on automation does the rest of the trip including landing. They are thinking that maybe in 10 years or even less, the aircraft will fly itself. 

Very sad, they will also then replace the rest of the flight crew with robots, remove the pax windows, and reduce us to below the cattle we already are, while increasing costs to justify their investment on automation.  I will choose not to fly, one has to just think of "Johnny Cab" from the movie total recall, or the Right Stuff.  We are moving to an Orwellian society and I am happy my body will be removed from this earth before it comes to fruition.  And we will still have an increasing mass of poverty, just like the post moon landing layoffs that happened putting highly educated people out of work and into flipping burgers and working a second job just to make ends meet.

3 hours ago, John_Cillis said:

I still believe some of this automation is unneeded, takes pilot control away by increasing the reaction time needed to overcome the automation.  Tens of thousands of previous gen 737 flights have proven it was fine without the MAX's automation, unless the MCAS was installed on those aircraft, again something probably already discussed and answered somewhere in this thread.  Add to that, tens of thousands of other flights, on other aircraft, in the years before automation really kicked in. 

The MCAS was added to the MAX series because they fly differently than the previous generation when near a stall. This is due to the larger engines used. While the engine nacelles are designed to not generate extra lift in typical take-off and cruise attitudes, they will begin to produce lift when you near a stall, thus potentially making things worse and responding differently than what pilots were used to. Also, how to deal with the changes was not communicated to the pilots, who would have fallen back to their training on the older models. It's explained in more detail in the article below.

https://leehamnews.com/2018/11/14/boeings-automatic-trim-for-the-737-max-was-not-disclosed-to-the-pilots/

2 hours ago, John_Cillis said:

I notice less side visibility in the pilot's office, wonder why they decreased that.  

 

The cockpit windows look to be the same size to me, just from different perspectives. Not to mention the size difference between the aircraft.

5 minutes ago, goates said:

The MCAS was added to the MAX series because they fly differently than the previous generation when near a stall. This is due to the larger engines used. While the engine nacelles are designed to not generate extra lift in typical take-off and cruise attitudes, they will begin to produce lift when you near a stall, thus potentially making things worse and responding differently than what pilots were used to. Also, how to deal with the changes was not communicated to the pilots, who would have fallen back to their training on the older models. It's explained in more detail in the article below.

https://leehamnews.com/2018/11/14/boeings-automatic-trim-for-the-737-max-was-not-disclosed-to-the-pilots/

Thanks for the explanation, I have not paid attention to the engine nacelles when I have seen pics of the MAX so I will have to take another look.

Found a good link with good photos too, if it has not already been shared...

http://www.flightstory.net/20151212/first-boeing-737-max-8-what-is-new

Edited March 21, 20197 yr by John_Cillis

3 minutes ago, John_Cillis said:

Thanks for the explanation, I have not paid attention to the engine nacelles when I have seen pics of the MAX so I will have to take another look.

This article has a good diagram comparing the NG and MAX engine designs. Note how much larger the MAX engines are.

 

https://www.latimes.com/local/california/la-fi-boeing-max-design-20190315-story.html

29 minutes ago, goates said:

This article has a good diagram comparing the NG and MAX engine designs. Note how much larger the MAX engines are.

 

https://www.latimes.com/local/california/la-fi-boeing-max-design-20190315-story.html

Yes indeed.  I remember when the 737-300 first came out and I took my first flight on one, on AirCal some decades ago, I stared at the engine cowling but knew immediately it's shape was due to the gear length.  I enjoy flying the 737 more than the airbus due to the slightly larger window size, and window position, but my fav aircraft in terms of window position was the 767 series, and also the CRJ 700/900.  I hated flying in the CRJ 200 because the windows were so low, and I am so tall from the waist up, that I could not see the sky unless I bent down, and that made me prone to motion sickness on that aircraft. 

I did love my last flight between PHX-London and back in 2017 on a BA 747-400 in premium economy.  I sat well forward of the wing and engine but could see both if I looked back, great for window views.  But I made the decision if I fly again to Europe, possibly as early as this fall, that I will go aisle since I had an uncooperative woman who not only pulled down my window shades in daylight but also refused to stand up to let me go to the facilities, I call such people seat trolls, and being a tall slender man now it is hard for me to walk over someone's legs in with the cramped pitch without stepping on their feet. 

Same thing happened to me on a flight from Tokyo to SFO in '92, which was my longest flight in terms of duration ever flown, and that does not include the three hour hop out of Guam to get to Tokyo for my transfer.  I had an eight hour layover at Narita, and a military traveler in civilian clothes told me to go to the help desk for NWA, that they'd give me a free hotel and meal voucher so I could lay down.  He saw that I had come down with a cold because my trip to Guam was part of a whirlwind series of flights that started from SFO to Orlando and back ten days before.  Nice man, I got to see Japan's lovely architecture outside of Tokyo, green farmland in hues I'd never seen, our coach to the hotel had a lovely hostess with a soft voice, I ate a great breakfast since my flight out of Guam left at 5AM, and got a good three hours rest at the hotel before I went back to Narita to go to its observation deck.  Like Bill Murray in the movie "Lost in Translation" I was amused because I towered over most of the Asian people who were in Narita's booking hall, whereas in the US at just shy of six feet I am average height and build.

This thread has taught me so much I did not know before about airline transport and where it is headed as aviation drives for fuel efficiency and increased safety and cabin comfort.

John

Edited March 21, 20197 yr by John_Cillis

8 hours ago, goates said:

The MCAS was added to the MAX series because they fly differently than the previous generation when near a stall. This is due to the larger engines used. While the engine nacelles are designed to not generate extra lift in typical take-off and cruise attitudes, they will begin to produce lift when you near a stall, thus potentially making things worse and responding differently than what pilots were used to. Also, how to deal with the changes was not communicated to the pilots, who would have fallen back to their training on the older models. It's explained in more detail in the article below.

https://leehamnews.com/2018/11/14/boeings-automatic-trim-for-the-737-max-was-not-disclosed-to-the-pilots/

The engines because of their relocation and increased power, produce a pitch up  moment moment when power is applied  which is opposite of what you need for stall recovery. This is what makes MCAS necessary. 

24 minutes ago, Bobsk8 said:

The engines because of their relocation and increased power, produce a pitch up  moment moment when power is applied  which is opposite of what you need for stall recovery. This is what makes MCAS necessary. 

Bob -- as I explained earlier on in this thread (and as @goates pointed out) whilst there is a pitch up moment when thrust is applied this is true of all aircraft with underslung engines.

MCAS is not a stall recovery/anti-stall system as has been described (as an oversimplification) in the popular media -- neither Boeing nor the FAA will describe it as such. If it were as simple as that then a stick pusher would have been used instead -- very simple, proven technology which has been in use on many other airline types for many years! 

On the contrary, it is there to make the aircraft handle like an NG in certain (high AoA) flight regimes and to comply with the requirements of FAR25.173. The FAR25 certification tests that resulted in MCAS are done with constant thrust so there is no additional pitching moment to consider -- it is an aerodynamic effect that is the problem.

49 minutes ago, skelsey said:

Bob -- as I explained earlier on in this thread (and as @goates pointed out) whilst there is a pitch up moment when thrust is applied this is true of all aircraft with underslung engines.

MCAS is not a stall recovery/anti-stall system as has been described (as an oversimplification) in the popular media -- neither Boeing nor the FAA will describe it as such. If it were as simple as that then a stick pusher would have been used instead -- very simple, proven technology which has been in use on many other airline types for many years! 

On the contrary, it is there to make the aircraft handle like an NG in certain (high AoA) flight regimes and to comply with the requirements of FAR25.173. The FAR25 certification tests that resulted in MCAS are done with constant thrust so there is no additional pitching moment to consider -- it is an aerodynamic effect that is the problem.

If you look at the video  I posted above on this thread.  from a real 737 pilot with over 12,000 hours, he explains the normal pitch up under full power of all 737's and the increased pitch up of the Max, due to  the larger engines and forward placement of the engines  

 

 

12 hours ago, Bobsk8 said:

Both Airbus and Boeing are working on pilot less aircraft. The one of the  largest expenses in aviation are pilots salaries. Currently the pilot for the most part, flies the aircraft up to about 600 feet , AP on, and from then on automation does the rest of the trip including landing. They are thinking that maybe in 10 years or even less, the aircraft will fly itself. 

Not just that,

you got hotac, taxis, sim training, recurrent training, line checks, and ftls would all be a thing of the past if we got rid of drivers and had robots flying planes. 

You'd also get rid of a ton of airline office  staff that manage all of the above.  Myself included. 

 

 

57 minutes ago, Bobsk8 said:

If you look at the video  I posted above on this thread.  from a real 737 pilot with over 12,000 hours, he explains the normal pitch up under full power of all 737's and the increased pitch up of the Max, due to  the larger engines and forward placement of the engines  

With respect, Bob (and with respect to the gentleman in the video) - however many hours he has, I am afraid he is incorrect.

Yes, there is a pitch up moment (not just with full thrust, ANY time the power is increased -- and, by extension, a pitch down whenever thrust is decreased) on all aircraft wtih underslung engines, including all variants of the 737 and certainly the Max is no exception.

But we know from Boeing that the reason for MCAS is to comply with the FAR 25.173 longtiudinal stability requirement around stick force gradient per knot of airspeed below trimmed speed, and that is tested with constant thrust.

So if you trim the aircraft for level flight at a set thrust, then start pulling back to reduce airspeed and do not touch the thrust levers, there cannot possibly be any additional pitch-up moment: the thrust stays the same, the thrust line stays the same and the CG of the aircraft all stay the same, therefore the nose-up pitching moment must also stay the same as it was in level flight. The additional pitch up at certain AoA is due to the larger (in size) engines and the fact that they are now more forward of the CG which means that the lift created by the nacelles now has a longer arm to work with compared to the NG and results in a nose-up moment once the aircraft passes a certain AoA (and the lift created by the nacelles starts to become significant -- obviously at low AoA the nacelles are engineered to create very little lift as the L/D ratio of an engine nacelle is pretty shocking).

The gentleman in the video you have linked then goes on to talk about the MCAS 'pushing the thrust levers full forward' -- which a) would be news to literally everyone as far as I can see and b) would be completely illogical if the claim is that MCAS is there to reduce the thrust couple. I mean, however bizarre one might think Boeing's thinking would be, it would be patently ridiculous to create a system designed to reduce the nose-up thrust couple which simultaneously fights against itself by applying full thrust would it not?

Further, if the point of MCAS was to reduce the thrust couple, why would it take an input from an AoA sensor and not thrust lever position/N1?

We don’t know that it is Boeing’s reason. And I’m pretty sure anybody that is currently working at boeing is not going to be on pprune being so vocal as to This Is Why. We know that it is fceng84’s assertion on pprune that it is for negative longitudinal stability at high alpha. He makes a good case and sounds knowledgeable. I’m not saying he is wrong, but I am pushing back on the apparent acceptance that this is at this point factual and according to Boeing. I’ve queried my brother who was formerly employed at boeing as a human factors expert working in procedures, about this. He has heard nothing about this dynamic stability issue being the reason. Granted he left boeing after the 787 and 747-8 were finished, so was not involved with max development, but did do some production test flights of the NG. Boeing has been concerned by pilot’s difficulty with keeping the nose down during go arounds and stalls which have been an issue for 737s, and most jets. There has been several near disasters because of this issue, recorded by boeing.

I personally am not on the 737 and have never flown one nor does my airline have any in the fleet. I’m on the E190 and did spend 2 hours on the last recurrent doing full stalls and stall recovery while staying at a Holiday Inn Express for 2 nights. This is apparently the new It thing for the FAA in this year’s recurrent for all the airlines. The culmination of the colgan and air france accidents and new algorithms in the sims now.  What I walked away from that with, having not done any real stalls since GA days, is that how well this turns out depends on how well you push on the stick. From breaking the stall, to recovering back to normal, level flight, it is an exercise of how you’re pushing on the stick. You need to push the stick hard enough to break the stall, then while bringing the nose back up to level flight, you are still pushing on the stick, through the entire recovery. If you even just relax the forward pressure, you are right back into the shaker. This is because, as shown by the instructors who recorded all the flight parameters through each stall and recovery, the recovery has you riding right along max aoa, as you are bringing the nose up to level and accelerating. Even on the E190, where Embraer redesigned the landing gear and wing to accomodate a bigger engine and didnt extend it out like the max, I am pushing to keep the plane from stalling. So I don’t doubt that Boeing would add a component of nose down trimming in that flight regime, since this plane was developed post colgan and af crashes, where the difficulty in keeping the nose down during go arounds, stalls and stall recovery is well known for this class of aircraft.

Edited March 21, 20197 yr by KevinAu

Just been reading that Boeing will now include one of the optional extras as standard, a disagree light but the angle of attack indicators will remain an optional extra , Boeing  makes a lot of money from optional extras it`s said as the big airlines include them.

1 hour ago, rjfry said:

Just been reading that Boeing will now include one of the optional extras as standard, a disagree light but the angle of attack indicators will remain an optional extra , Boeing  makes a lot of money from optional extras it`s said as the big airlines include them.

So they are offering  an optional extra, and if the airline doesn't go for it, the result may be a crash......nice.!!!!

19 hours ago, John_Cillis said:

Please relax and bear with some of us, there are so many replies in this thread, some speculative and some not, that it is hard to weed thru them all.

John,

please excuse if my wording sounded harsh in any way, it wasn't meant to be. I was merely astounded because the purpose of MCAS had been discussed at length. No harm done I hope.

Without wanting to go off-topic, when the day comes that aircraft fly themselves with no pilots I can't see how I'm still interested so much in (commercial) flying. Aviation is so much about people, pilots and the required teamwork in any flight deck, ATC as the pilot's best friend, etc. On the other hand, I'm a bit skeptical about 'robot planes' because of the psychological part - considering the general public lack knowledge about flying in general and the abundance of misinformation about aircraft and aviation as a whole out there I would assume not too many people would happily put themselves in aircraft with no pilots.