Rogue Boeing 737 Max planes ‘with minds of their own’ | 60 Minutes Australia

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I'm glad to hear that boatgeek! Thanks!

We do have the best flight attendants in the world, I think.

And, this might be an odd thing to say, but I think we have the best passengers in the world also! I'm always amazed at how nice 99.5% of our passengers are, even during long delays and unforeseen issues.

The best part of my current job is that the owner wants to pursue good clients. If someone's a cheapskate or a complete jerk, he doesn't want the business because it's not worth the time, effort, and writeoffs that it takes to keep them slightly less unhappy. That's probably true in other industries as well. :)
 
We do have the best flight attendants in the world, I think.

And, this might be an odd thing to say, but I think we have the best passengers in the world also! I'm always amazed at how nice 99.5% of our passengers are, even during long delays and unforeseen issues.

As an engineer for Recaro, I have to say you also have amazing seats! :D
So glad to see the MAX taking off again.
 
As an engineer for Recaro, I have to say you also have amazing seats! :D
So glad to see the MAX taking off again.
Yes, but the flight crew has Ipeco seats. I'm the Service Engineer who answers questions related to them and works with Ipeco as needed.
I also deal with all the other seats on all the Boeing/Douglas models (except 787), such as passenger seats, attendant seats, observer seats, supernumerary seats, crew rest seats. But not the toilet seats....
 
Yes, but the flight crew has Ipeco seats. I'm the Service Engineer who answers questions related to them and works with Ipeco as needed.
I also deal with all the other seats on all the Boeing/Douglas models (except 787), such as passenger seats, attendant seats, observer seats, supernumerary seats, crew rest seats. But not the toilet seats....

I think Ipeco made the seats for the C-5 also.
 
The best part of my current job is that the owner wants to pursue good clients. If someone's a cheapskate or a complete jerk, he doesn't want the business because it's not worth the time, effort, and writeoffs that it takes to keep them slightly less unhappy. That's probably true in other industries as well. :)
This, and having crappy coworkers, is sometimes called the Total Cost of A**holes
 
The Recaro seats are amazing! Very comfortable and well made!
I don't know anything about seats except that Southwest must not be one of their customers. Sure, the tickets are cheap, but I've sat in wooden church pews and steel folding chairs that were more comfortable. :)
 
You get what you pay for, sometimes.

Southwest has great pilots and employees, The planes are well maintained but the interiors are old school and cramped.

We spend a lot of money on the interiors of our planes to make a better experience for our passengers. The Recaro seats are not cheap, but they pay for themselves in the long run with happy passengers and lower maintenance costs. We also have huge overhead bins on most of our aircraft that fit more carryons. It's what the passengers want.
 
This, and having crappy coworkers, is sometimes called the Total Cost of A**holes
The company I work for puts lots of effort in when hiring. We get people in the top 5% of just about everything. I makes for a really pleasant work environment, Almost no politics and everyone works well together. Very few abrasive personalities. I am sure this is money in the bank for the company.
 
I'm not sure it's really relevant, or anyone cares, But I finally flew the MAX on the line yesterday.

A Seattle San Fran turn. About 5 hours of flying for 2 legs.

hssNmKeh.jpg


1st impressions are all very positive. It flew very nice and the flight controls are very balanced. As a longtime
737 driver I was comfortable in the cockpit, a few secondary controls/switches have been moved but everything is logical. The biggest gripe is they moved the rudder trim knob about 1/2 an inch forward on the center panel. I never look for it, i just reach back for it and because of muscle memory I kept just missing it.
No big deal, just a minor "Doh".

The displays are beautiful, and the information is very well presented.

kYcbZ2Hh.jpg


I don't normally do the walk around, but I did to get a handle on the outside changes. It's one thing to see photo's or look at it from a distance....Oh, who am I kidding I just wanted to check it out!

It has.... huge tracts of open land! Check out the Leap! Massive for a single aisle aircraft.

hEXNEpRh.jpg


ScHLenqh.jpg


And the blades are a work of art.

A7p87Lih.jpg


The new winglets sick out farther than on the NG, I'll have to be carful on the ground.

Nm3IIHPh.jpg


Taxiing is interesting, the Leap's have so much idle thrust it scoots along, and the carbon brakes really
work good! That takes some getting used to.

The sound the engines make on take off is just cool! The kind of growl rather than buzz.

But the cruise fuel burn was incredible! At Mach .78 and 37,000ft, with a full (170 passengers) aircraft our fuel burn was 2320 pounds of fuel per hour for each engine!

Dwa3xjOh.jpg


To give a comparison, the 737-900NG would be burning about 3100# per side.

We have A-321NEO's also, they are incredible also on the fuel burn but still higher than the MAX. I'll have to ask around, but I think the Airbus runs around 2500 Pounds per hour per side.

Airliners are revenue generation machines, as such the MAX is very, very good. As a pilot it was very pleasant fly, and our passengers seem to like riding in it.
 
To give a comparison, the 737-900NG would be burning about 3100# per side.

We have A-321NEO's also, they are incredible also on the fuel burn but still higher than the MAX. I'll have to ask around, but I think the Airbus runs around 2500 Pounds per hour per side.

Airliners are revenue generation machines, as such the MAX is very, very good. As a pilot it was very pleasant fly, and our passengers seem to like riding in it.

Thanks, very interesting to get an insiders perspective.
 
I'm not sure it's really relevant, or anyone cares, But I finally flew the MAX on the line yesterday.

A Seattle San Fran turn. About 5 hours of flying for 2 legs.

hssNmKeh.jpg


1st impressions are all very positive. It flew very nice and the flight controls are very balanced. As a longtime
737 driver I was comfortable in the cockpit, a few secondary controls/switches have been moved but everything is logical. The biggest gripe is they moved the rudder trim knob about 1/2 an inch forward on the center panel. I never look for it, i just reach back for it and because of muscle memory I kept just missing it.
No big deal, just a minor "Doh".

The displays are beautiful, and the information is very well presented.

kYcbZ2Hh.jpg


I don't normally do the walk around, but I did to get a handle on the outside changes. It's one thing to see photo's or look at it from a distance....Oh, who am I kidding I just wanted to check it out!

It has.... huge tracts of open land! Check out the Leap! Massive for a single aisle aircraft.

hEXNEpRh.jpg


ScHLenqh.jpg


And the blades are a work of art.

A7p87Lih.jpg


The new winglets sick out farther than on the NG, I'll have to be carful on the ground.

Nm3IIHPh.jpg


Taxiing is interesting, the Leap's have so much idle thrust it scoots along, and the carbon brakes really
work good! That takes some getting used to.

The sound the engines make on take off is just cool! The kind of growl rather than buzz.

But the cruise fuel burn was incredible! At Mach .78 and 37,000ft, with a full (170 passengers) aircraft our fuel burn was 2320 pounds of fuel per hour for each engine!

Dwa3xjOh.jpg


To give a comparison, the 737-900NG would be burning about 3100# per side.

We have A-321NEO's also, they are incredible also on the fuel burn but still higher than the MAX. I'll have to ask around, but I think the Airbus runs around 2500 Pounds per hour per side.

Airliners are revenue generation machines, as such the MAX is very, very good. As a pilot it was very pleasant fly, and our passengers seem to like riding in it.

Good to hear that you had a positive experience. An exceptionally geeky question: Is main power on the aircraft really AC at 400 Hz as shown on the power plug door? Do you know why they did that as opposed to something more "normal" like 50 or 60 Hz?
 
Good to hear that you had a positive experience. An exceptionally geeky question: Is main power on the aircraft really AC at 400 Hz as shown on the power plug door? Do you know why they did that as opposed to something more "normal" like 50 or 60 Hz?

Total WAG, but I bet it is to make voltage conversion circuits smaller and more efficient.
 
Good to hear that you had a positive experience. An exceptionally geeky question: Is main power on the aircraft really AC at 400 Hz as shown on the power plug door? Do you know why they did that as opposed to something more "normal" like 50 or 60 Hz?

All the aircraft I've flown have been 3 phase 115V 400 Hz AC, I was told as a young Air Force pilot it was for the Avionics but I suspect mbeels is at least partially correct. We also have 28V DC on the aircraft powered by TR's and 2 batteries.
 
Eric,

Yes, 400 Hz and no, I don't know why.

Mark,

I'm glad you like the display system. That was one of the few significant changes that made it into the Max that wasn't directly a consequence of the "get better gas milage" overall objective of the thing. Of course going to those 787 displays (they are, or should be, the same part number even) caused a bunch of ripple effect in locations of some other things on the flight deck, but I can't recall why the rudder trim knob was moved, since it's nowhere near the forward displays. I vaguely recall some other machinations around stuff in the aisle stand but from this distance (retired almost five years now) I don't recall the specifics.

My former colleagues in the Flight Deck and Flight Crew Operations organizations would be glad to hear that you like how the information is presented on the new displays.

The high idle thrust coupled with carbon brakes (no steel option as on the NG—a choice that costs several hundred pounds of weight for steel) was known to be an "interesting" situation that there was no good answer to as CFM dialed back the idle thrust on the LEAP-1B engine as far as they thought they could get away with and there's no good way (or wasn't at the time) of softening the response of carbon brakes. Hopefully your maintenance guys won't need to replace brakes more frequently than they should. As I understood it, carbon brake wear is governed more by how many times the brakes are actuated rather than how hard they are actuated. Time will tell, I am sure.
 
Thanks for your perspective on the 737. Sounds nice.

It has.... huge tracts of open land! Check out the Leap! Massive for a single aisle aircraft.
I was going to say what a work of art the blades are on that engine, but then I scrolled down and you already had :).

Good to hear that you had a positive experience. An exceptionally geeky question: Is main power on the aircraft really AC at 400 Hz as shown on the power plug door? Do you know why they did that as opposed to something more "normal" like 50 or 60 Hz?
I think this is the way it has been done for years. The generators run off a gear pickup on the turbine shafts. This means they are turning quite fast. In earlier days they would use a hydraulic speed compensator (variable-volume pump and a motor) to control the speed into the alternators within a relatively small range, giving the approximately 400Hz power. From what I can recall it is not really stable in frequency, just a nominal 400Hz.

Looking at the 787 they use variable frequency starter generators. This is a more contemporary approach and the electrical systems are designed to accept the range of frequencies. They produce 360-800Hz which is proportional to the speed of the turbine. This eliminates the mass required for the hydraulic speed regulating system used on earlier craft. The other advantage of this is that they can be used to turn the engine, completely eliminating the need for a bleed-air system for starting them up and also simplifying the APU. Each engine has two 250kW VFSGs for redundancy.
https://www.boeing.com/commercial/aeromagazine/articles/2012_q3/2/https://www.boeing.com/commercial/aeromagazine/articles/qtr_4_07/article_02_3.html
I have the service training manual for the 787 and it is an awesome piece of engineering. Viva la progress!
 
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Is main power on the aircraft really AC at 400 Hz as shown on the power plug door? Do you know why they did that as opposed to something more "normal" like 50 or 60 Hz?
400 Hz power has been a standard on aircraft for decades, going back to at least the 1970's.
The higher frequency allowed designers to use smaller magnetics, which besides being smaller were lighter. Weight has always been an issue with aircraft. I recall various of our products where they literally machined screw heads down to save ounces....
Many sensors, such as resolvers, syncros, and LVDTs/RVDTs, used the 400Hz as excitation and since they are based on transformers, again allowed for size/weight reduction.
Now days most modern aircraft have the electronics generate these excitation frequencies in the 2000 ~ 4000Hz range, allowing even further reduction in size/weight for the sensors. But many systems still carry over and use the 400Hz power
 
I think this is the way it has been done for years. The generators run off a gear pickup on the turbine shafts. This means they are turning quite fast. In earlier days they would use a hydraulic speed compensator (variable-volume pump and a motor) to control the speed into the alternators within a relatively small range, giving the approximately 400Hz power. From what I can recall it is not really stable in frequency, just a nominal 400Hz.
400 Hz power has been a standard on aircraft for decades, going back to at least the 1970's.
The higher frequency allowed designers to use smaller magnetics, which besides being smaller were lighter. Weight has always been an issue with aircraft. I recall various of our products where they literally machined screw heads down to save ounces....
Many sensors, such as resolvers, syncros, and LVDTs/RVDTs, used the 400Hz as excitation and since they are based on transformers, again allowed for size/weight reduction.
Now days most modern aircraft have the electronics generate these excitation frequencies in the 2000 ~ 4000Hz range, allowing even further reduction in size/weight for the sensors. But many systems still carry over and use the 400Hz power

Thanks to both for your expertise. After posting, I thought I remembered something about there being less EMI with the higher frequency, but the weight savings make more sense.

A friend who interned at Boeing years ago had people come back and ask if they could use a smaller bolt on [something] to save a gram or two. I like working on relatively low-speed boats where weight is far less of an issue.
 
BTW - I know in the 70's/80's our company also made a variable speed constant frequency generator, so regardless of the engine RPM it produced 400Hz. It used electronics to perform this conversion....
 
BTW - I know in the 70's/80's our company also made a variable speed constant frequency generator, so regardless of the engine RPM it produced 400Hz. It used electronics to perform this conversion....
The semiconductors have improved in reliability over the years, especially the last 20 for things like power conversion. That makes the old mechanical way of doing CSG outdated, since the electronics reliability is now acceptable for the mass savings of removing the mechanical speed conversion.
 
We looked at both variable frequency power (ala 787) on the MAX and at fitting VSCFs. Neither idea bought their way onto the airplane for various reasons mostly due to the ripple effect on what other things would have to change and on fleet/spares commonality. So the basic electric power system that's been on the 737 family at least since the Classics (-300/-400/-500) and probably since the original -100/-200 is still in place on the MAX. There are many detail improvements, but the overall architecture that's based on 400 Hz 120V AC is still there.
 
I don't know anything about seats except that Southwest must not be one of their customers. Sure, the tickets are cheap, but I've sat in wooden church pews and steel folding chairs that were more comfortable. :)
Hmm. I always found SW seats perfectly fine; of course, I'm only 5'9" :rolleyes:
(For most of last decade I averaged close to 2 flights per week).
 
It's interesting to hear the engineering perspective! The every turbine aircraft I've flown prior to the NG used CSD's (Constant speed drive) to govern the speed of the generator for 400Hz output (what OverTheTop described). When we got the NG's the training department made a huge deal about the fact that it now had IDGs (Integrated drive generators). No more CSDs!
All us line meat servos cared about was did we have to do anything different, IDG vs CSD. The answer was "No, but the IDG is sooo much better!" they proceeded to tell us why, and our eyes glassed over.
Maintenance loves the IDGs, much more reliable and easier to work on.
 
I'm not sure it's really relevant, or anyone cares, But I finally flew the MAX on the line yesterday.

A Seattle San Fran turn. About 5 hours of flying for 2 legs.

hssNmKeh.jpg


1st impressions are all very positive. It flew very nice and the flight controls are very balanced. As a longtime
737 driver I was comfortable in the cockpit, a few secondary controls/switches have been moved but everything is logical. The biggest gripe is they moved the rudder trim knob about 1/2 an inch forward on the center panel. I never look for it, i just reach back for it and because of muscle memory I kept just missing it.
No big deal, just a minor "Doh".

The displays are beautiful, and the information is very well presented.

kYcbZ2Hh.jpg


I don't normally do the walk around, but I did to get a handle on the outside changes. It's one thing to see photo's or look at it from a distance....Oh, who am I kidding I just wanted to check it out!

It has.... huge tracts of open land! Check out the Leap! Massive for a single aisle aircraft.

hEXNEpRh.jpg


ScHLenqh.jpg


And the blades are a work of art.

A7p87Lih.jpg


The new winglets sick out farther than on the NG, I'll have to be carful on the ground.

Nm3IIHPh.jpg


Taxiing is interesting, the Leap's have so much idle thrust it scoots along, and the carbon brakes really
work good! That takes some getting used to.

The sound the engines make on take off is just cool! The kind of growl rather than buzz.

But the cruise fuel burn was incredible! At Mach .78 and 37,000ft, with a full (170 passengers) aircraft our fuel burn was 2320 pounds of fuel per hour for each engine!

Dwa3xjOh.jpg


To give a comparison, the 737-900NG would be burning about 3100# per side.

We have A-321NEO's also, they are incredible also on the fuel burn but still higher than the MAX. I'll have to ask around, but I think the Airbus runs around 2500 Pounds per hour per side.

Airliners are revenue generation machines, as such the MAX is very, very good. As a pilot it was very pleasant fly, and our passengers seem to like riding in it.
Does the Max have a RAT or use other means for emergency power/hydraulics?
 
Does the Max have a RAT or use other means for emergency power/hydraulics?
No member of the 737 family has a RAT. It has a manual-reversion flight control system—it can be flown without benefit of hydraulics, though I expect it's not much fun. The gear can be dropped without power as well. Preserving this capability as the airplane has grown over the years has been one of the key design constraints.
 
[snip]
Many sensors, such as resolvers, syncros, and LVDTs/RVDTs, used the 400Hz as excitation and since they are based on transformers, again allowed for size/weight reduction.
[/snip]

I had never heard of a resolver until I joined my current company (20 years ago, but still. . .). Once I learned more about them, they were really cool technology, especially given when they were developed. Our more current implementation of resolvers uses 5kHz as the excitation frequency, but the original units were absolutely 400Hz, but I never knew why. I originally didn't know why they had a 'Buord' number for the interface vs a NEMA or similar either, but I found out one day. So cool for connections to be made still so many years later. . .(also 'Connections' was a cool TV show growing up. . . ).

Sandy.
 
No member of the 737 family has a RAT. It has a manual-reversion flight control system—it can be flown without benefit of hydraulics, though I expect it's not much fun. The gear can be dropped without power as well. Preserving this capability as the airplane has grown over the years has been one of the key design constraints.

I have, manual reversion is not great, but the airplane can be flown very well on it.
 

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