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Revelation
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How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 4:21 pm

Finally we get the goods, in high resolution video too!

https://www.youtube.com/watch?v=F4IGl4OizM4

http://www.boeing.com/features/2018/08/ ... 08-18.page

What makes this landing gear so unique? It has two key features that are critical for the longer design of the MAX 10: A lever that allows the landing gear to grow taller upon takeoff, and a shrinking mechanism that helps the gear retract to fit into the existing wheel well.

I don't understand why growing taller "upon takeoff" is sufficient.

I presume this means they don't want the telescoping gear to take the full load of the a/c so they wait till the wings are generating lift and then let the gear grow taller? I guess this gives it a bit more stability as it rotates, but avoids taking the full load?

What happens if the takeoff is aborted right after rotation?
Last edited by Revelation on Thu Aug 30, 2018 4:30 pm, edited 1 time in total.
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WIederling
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 4:29 pm

Isn't that about what the A330/A340 "heel dragging" boggie arrangement does?
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 4:32 pm

So instead of moving the pivot point backwards like the E-190 as some initially speculated, they seems like they have essentially kept the gear on the ground longer by extending it on rotation once the plane starts producing lift to give it a better rotation angle.
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 4:36 pm

osupoke07 wrote:
So instead of moving the pivot point backwards like the E-190 as some initially speculated, they seems like they have essentially kept the gear on the ground longer by extending it on rotation once the plane starts producing lift to give it a better rotation angle.

It is all about avoiding tail strikes allowing a steeper early climb to get off the runway and up high enough to maximize the number of airports.

I'll look forward to seeing the video later.

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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 4:36 pm

Revelation wrote:
I don't understand why growing taller "upon takeoff" is sufficient.

By growing taller the bottom of the fuselage is higher off the ground and can rotate more without striking the ground.
 
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 4:41 pm

osupoke07 wrote:
So instead of moving the pivot point backwards like the E-190 as some initially speculated, they seems like they have essentially kept the gear on the ground longer by extending it on rotation once the plane starts producing lift to give it a better rotation angle.

Interesting how they don't show the landing sequence.

Do they land in telescoping position and retract as more weight is on the wheels, or land in "traditional" non-telescoping position?
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 4:46 pm

Interesting -- Nothing fancy here but a new lever and linkage carrying the wheels. But its late in the 737 lifecycle...

...So why wasn't something like this done decades ago, allowing an engine with a bigger fan for efficiency under the 737 wing? Also fixing the 739 rotation and runway length issue?
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 4:52 pm

QuarkFly wrote:
Interesting -- Nothing fancy here but a new lever and linkage carrying the wheels. But its late in the 737 lifecycle...

...So why wasn't something like this done decades ago, allowing an engine with a bigger fan for efficiency under the 737 wing? Also fixing the 739 rotation and runway length issue?

The way I understand it, it doesn't increase the engine clearance and only works when the wings are producing lift. It works similar to semi levered gear on the 77W and the 787-10.
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 4:56 pm

Revelation wrote:
osupoke07 wrote:
So instead of moving the pivot point backwards like the E-190 as some initially speculated, they seems like they have essentially kept the gear on the ground longer by extending it on rotation once the plane starts producing lift to give it a better rotation angle.

Interesting how they don't show the landing sequence.

Do they land in telescoping position and retract as more weight is on the wheels, or land in "traditional" non-telescoping position?


I think how A330 lands is a decent comparison..sort of.

https://www.youtube.com/watch?v=lowrM-780tg


So I assume the actual height on the ground will remain unchanged?
 
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 5:00 pm

Revelation wrote:
What happens if the takeoff is aborted right after rotation?


Surely after rotation is well after V1, so any abort is only for an unflyable aircraft, in which case the length of the landing gear might be the least of their problems.
 
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 5:07 pm

QuarkFly wrote:
Interesting -- Nothing fancy here but a new lever and linkage carrying the wheels. But its late in the 737 lifecycle...

...So why wasn't something like this done decades ago, allowing an engine with a bigger fan for efficiency under the 737 wing? Also fixing the 739 rotation and runway length issue?

Because it wasn't needed before. It was done now because the extra 66 inches of length increased the danger of tail-strike. Boeing didn't want to do a costly MLG change that would also have involved major surgery to the wingbox and would have mandated other costly changes to the airplane, as well. The basic need to deal with that specific modest stretch demanded an innovative solution that avoids far costlier modifications that also would reduce commonality with other MAX models.
 
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 5:10 pm

So this does nothing to help with tailstrikes on landing, only work to “catapult” the airplane off the runway. Color me unimpressed.

Ok, I have now noticed how the bottom end extension also drops down on landing, but unless there is a serious downward force on that linkage, it will hardly help with a hard landing, tailstrike case. Time will tell.
Last edited by arcticcruiser on Thu Aug 30, 2018 5:19 pm, edited 1 time in total.
 
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 5:11 pm

Revelation wrote:
osupoke07 wrote:
So instead of moving the pivot point backwards like the E-190 as some initially speculated, they seems like they have essentially kept the gear on the ground longer by extending it on rotation once the plane starts producing lift to give it a better rotation angle.

Interesting how they don't show the landing sequence.

Do they land in telescoping position and retract as more weight is on the wheels, or land in "traditional" non-telescoping position?


There is a short clip of a landing. See starting at 1:09 in the video. It appears to extend to the telescoped position, then compress once there is weight on the wheel.
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 5:11 pm

How is the innovative lever that retracts the inner cylinder on retraction any different from the same mechanism on the A330? It must be different or it would not be innovative. Or have they changed it slightly to get around a patent?
 
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 5:18 pm

817Dreamliiner wrote:
QuarkFly wrote:
Interesting -- Nothing fancy here but a new lever and linkage carrying the wheels. But its late in the 737 lifecycle...

...So why wasn't something like this done decades ago, allowing an engine with a bigger fan for efficiency under the 737 wing? Also fixing the 739 rotation and runway length issue?

The way I understand it, it doesn't increase the engine clearance and only works when the wings are producing lift. It works similar to semi levered gear on the 77W and the 787-10.


The 777 has a spur cylinder that locks the boogie and the airframe is forced to rotate around the rearmost axle.
the A330/A340 have linkage that pulls the front of the boggie up when load on the oleo goes down and it telescopes out.
That pushed the rear of the boogie down even further.
That seems to be about what the 737-10 does except that it has a "trailing half boogie" only.

Haven't looked at the 787 design.
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 5:36 pm

Tristarsteve wrote:
How is the innovative lever that retracts the inner cylinder on retraction any different from the same mechanism on the A330? It must be different or it would not be innovative. Or have they changed it slightly to get around a patent?


Simply designing a new mechanism does not necessarily qualify as a patentable intellectual property. Is there anything about the A330 or 737Max gear mechanisms that is innovative and non-obvious contribution to the field of linkages? Probably not. Of course, that doesn’t preclude vanity patents and puffery talk.
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 5:42 pm

This seems like it can easily be retrofitted to the other members like the MAX9?
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 6:08 pm

This all could have been easily avoided if they'd just kept the 757 line open and updated it!
 
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 6:11 pm

It makes sense that the gear extension remains compressed while on the ground. Otherwise, the plane would have quite a nose-down attitude versus all the other 737's. That would affect all the services accessing the plane. It would probably affect the plane's ground handling characteristics too.

As to an aborted takeoff, such a thing should not ever happen post-rotation. If you're at Vr, then you're past V1, and you've committed to the takeoff even in the event of an engine failure. If things are so bad that you're not able to take off post-rotation, then a tail-strike is probably the least of your worries. Am I wrong?
 
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 6:29 pm

I’d be interested in knowing the procedure for dealing with a failure to deploy and a failure to retract.
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 6:33 pm

Revelation wrote:
osupoke07 wrote:
So instead of moving the pivot point backwards like the E-190 as some initially speculated, they seems like they have essentially kept the gear on the ground longer by extending it on rotation once the plane starts producing lift to give it a better rotation angle.

Interesting how they don't show the landing sequence.

Do they land in telescoping position and retract as more weight is on the wheels, or land in "traditional" non-telescoping position?


The tail strike risk still exist on landing, so I assume I get the full length of the gear on landing too like in the 777 and A330/40.
 
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 6:43 pm

But how this mechanism is actually powered? Is this hydraulic or it's just sort of "oleo strut" that simply extends when wings start producing lift?
 
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 7:02 pm

osupoke07 wrote:
There is a short clip of a landing. See starting at 1:09 in the video. It appears to extend to the telescoped position, then compress once there is weight on the wheel.

You're right. I was so fixated on the left half of the image that I ignored the right half that showed the landing.

Virtual737 wrote:
Revelation wrote:
What happens if the takeoff is aborted right after rotation?

Surely after rotation is well after V1, so any abort is only for an unflyable aircraft, in which case the length of the landing gear might be the least of their problems.

Agree it should not be the determining factor, but one could imagine why one would at least want to think through what would happen even as a thought experiment. I suppose it'd be the same as the landing scenario, it'd compress as weight was added, presumably at some limited rate of compression.

PS: In case it isn't obvious, I suck at visualizing mechanical devices. Somehow I passed a class on dynamics during college, but thank god I was born in the computer age so I didn't have to try to make a living as a mechanical engineer!
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 7:09 pm

phllax wrote:
This all could have been easily avoided if they'd just kept the 757 line open and updated it!

But they'd have nowhere to park unfinished 737s! :biggrin:
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 7:11 pm

AleksW wrote:
But how this mechanism is actually powered? Is this hydraulic or it's just sort of "oleo strut" that simply extends when wings start producing lift?

Just like on the video, a crew member's arm reaches down and works the lever! :biggrin:
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 7:13 pm

This could make for smoother landings with such a long wheel travel.
 
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 7:24 pm

Oykie wrote:
This seems like it can easily be retrofitted to the other members like the MAX9?


Looks like it. I wonder how much it will weigh.

The 727 has a similar single bogie landing gear and was rated to 229,000lbs. So this really isn't "un precedented" territory at all.
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 7:41 pm

Tristarsteve wrote:
How is the innovative lever that retracts the inner cylinder on retraction any different from the same mechanism on the A330? It must be different or it would not be innovative. Or have they changed it slightly to get around a patent?

Patents expire after 17 years (at least in the US). It is also pretty easy to make changes that function the same but get around the patent.
 
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 7:43 pm

Thankfully I won't have to fly this thing! They should just put a main landing gear wheel on the nose and just pound it flat into the ground. So innovative, LMAO!!!
 
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 7:49 pm

Revelation wrote:
osupoke07 wrote:
So instead of moving the pivot point backwards like the E-190 as some initially speculated, they seems like they have essentially kept the gear on the ground longer by extending it on rotation once the plane starts producing lift to give it a better rotation angle.

Interesting how they don't show the landing sequence.

Do they land in telescoping position and retract as more weight is on the wheels, or land in "traditional" non-telescoping position?


I would "assume" (we all know what that does) that they would extend by gravity on approach and do the reverse of takeoff on touch down.

It seems from the video that the telescoping mechanism is automatic and doesn't "know" if it is extended for landing or it is taking off. It seems like the gear telescopes out whenever the gear is deployed and there is less than a certain weight threshold on it.
 
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 7:50 pm

Revelation wrote:
AleksW wrote:
But how this mechanism is actually powered? Is this hydraulic or it's just sort of "oleo strut" that simply extends when wings start producing lift?

Just like on the video, a crew member's arm reaches down and works the lever! :biggrin:

Well, at least not passengers :)
 
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 7:53 pm

Varsity1 wrote:
Oykie wrote:
This seems like it can easily be retrofitted to the other members like the MAX9?


Looks like it. I wonder how much it will weigh.

The 727 has a similar single bogie landing gear and was rated to 229,000lbs. So this really isn't "un precedented" territory at all.

I'd love to see a comparison between the two gear.

It would be bad to say we innovated by copying an over 50 year old design... ;)

Learned something new. In all fairness, 727s we're barely around at the start of my career.

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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 8:26 pm

lightsaber wrote:
Varsity1 wrote:
Oykie wrote:
This seems like it can easily be retrofitted to the other members like the MAX9?


Looks like it. I wonder how much it will weigh.

The 727 has a similar single bogie landing gear and was rated to 229,000lbs. So this really isn't "un precedented" territory at all.

I'd love to see a comparison between the two gear.

It would be bad to say we innovated by copying an over 50 year old design... ;)

Learned something new. In all fairness, 727s we're barely around at the start of my career.

Lightsaber


Boeing hasn't officially released the Max-10's MTOW. I can't help to wonder if they will make it applicable to the Max-9, similar to how the 737-900ER's weights are available on the -800NG as the 737-800ERX.

"737-Max9ERX" 4500nm? :scratchchin:
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 8:37 pm

fly4ever78 wrote:
Thankfully I won't have to fly this thing! They should just put a main landing gear wheel on the nose and just pound it flat into the ground. So innovative, LMAO!!!



It is innovative and an elegant cost effective solution to the extended fuselage issue. Why be so negative?
 
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 8:38 pm

phllax wrote:
This all could have been easily avoided if they'd just kept the 757 line open and updated it!


Agreed. The whole MAX stuff I'm seeing is proof that the 737 MAX 10 is as far as the 737 design can go.
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 8:45 pm

planecane wrote:
Revelation wrote:
osupoke07 wrote:
So instead of moving the pivot point backwards like the E-190 as some initially speculated, they seems like they have essentially kept the gear on the ground longer by extending it on rotation once the plane starts producing lift to give it a better rotation angle.

Interesting how they don't show the landing sequence.

Do they land in telescoping position and retract as more weight is on the wheels, or land in "traditional" non-telescoping position?


I would "assume" (we all know what that does) that they would extend by gravity on approach and do the reverse of takeoff on touch down.

It seems from the video that the telescoping mechanism is automatic and doesn't "know" if it is extended for landing or it is taking off. It seems like the gear telescopes out whenever the gear is deployed and there is less than a certain weight threshold on it.

I assume it would be more or less like a shock absorber on a car. However, I expect that the hydraulic pressure would be adjustable, depending on the weight of the plane. The difference between takeoff and landing weights could be quite significant. I don’t know if a passive system would suffice.
 
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 8:56 pm

Varsity1 wrote:
Oykie wrote:
This seems like it can easily be retrofitted to the other members like the MAX9?


Looks like it. I wonder how much it will weigh.

The 727 has a similar single bogie landing gear and was rated to 229,000lbs. So this really isn't "un precedented" territory at all.


IIRC 727 mlg tires were a lot bigger than 737 classic mlg tires. Not sure if NG or MAX tires are bigger than the classics, but a bigger footprint helps with ACN/PCN issues.
 
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 9:11 pm

Super80Fan wrote:
phllax wrote:
This all could have been easily avoided if they'd just kept the 757 line open and updated it!

Agreed. The whole MAX stuff I'm seeing is proof that the 737 MAX 10 is as far as the 737 design can go.

Already discussed to death. Please take it elsewhere.
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 10:21 pm

Last I heard, not official, the 737-10 MTOW was 92,000kg. Last time I looked, for comparison, MTOW of the 737-9 was 88,300kg.

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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 11:12 pm

arcticcruiser wrote:
So this does nothing to help with tailstrikes on landing, only work to “catapult” the airplane off the runway. Color me unimpressed.

Ok, I have now noticed how the bottom end extension also drops down on landing, but unless there is a serious downward force on that linkage, it will hardly help with a hard landing, tailstrike case. Time will tell.

planecane wrote:
I would "assume" (we all know what that does) that they would extend by gravity on approach and do the reverse of takeoff on touch down.

It seems from the video that the telescoping mechanism is automatic and doesn't "know" if it is extended for landing or it is taking off. It seems like the gear telescopes out whenever the gear is deployed and there is less than a certain weight threshold on it.

It points out that I don't really know the dynamics of what is going on at takeoff/touchdown time. Maybe I'm not alone on that.

The videos show on the takeoff roll that the wings are gradually developing lift so taking weight off the wheels. I imagine if the gear works like a hydraulic strut/shock the reduced weight allows the hydraulic fluid to enter via an aperture that limits rate of fluid flow. This means the gear will not rapidly compress if the weight should be reapplied, which is what you want. The opposite is true on landing: it's firmly extended on touchdown and then gradually compresses. The energy to move the fluid comes from gravity of the gear on takeoff and gravity of airplane on landing. Yet if this is not good enough, one could introduce a pump to move the hydraulic fluid, and that pump could be controlled by a microprocessor with various sensory inputs. I have absolutely no idea if such a pump is needed, since I absolutely suck at mechanics.

Where's a good mechanical engineer when we really need one?
Last edited by Revelation on Thu Aug 30, 2018 11:15 pm, edited 1 time in total.
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 11:14 pm

Ruscoe wrote:
Last I heard, not official, the 737-10 MTOW was 92,000kg. Last time I looked, for comparison, MTOW of the 737-9 was 88,300kg.

Ruscoe


What is that in pounds? We use pounds/lbs here, so it would be nice for people to post weights for planes built in America to be given in pounds as well.
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 11:16 pm

FriscoHeavy wrote:
Ruscoe wrote:
Last I heard, not official, the 737-10 MTOW was 92,000kg. Last time I looked, for comparison, MTOW of the 737-9 was 88,300kg.

Ruscoe

What is that in pounds? We use pounds/lbs here, so it would be nice for people to post weights for planes built in America to be given in pounds as well.

This is going to get really ugly really quickly...

Maybe google "92,000 kilograms in pounds" and save us the drama?
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 11:26 pm

FriscoHeavy wrote:
Ruscoe wrote:
Last I heard, not official, the 737-10 MTOW was 92,000kg. Last time I looked, for comparison, MTOW of the 737-9 was 88,300kg.

Ruscoe


What is that in pounds? We use pounds/lbs here, so it would be nice for people to post weights for planes built in America to be given in pounds as well.

NASA switched to metric after crashing their Mars lander. OOP$$$! Frankly, I'd be surprised if Boeing is currently designing their planes using standard measurements, given their need to work with suppliers from all over the globe.
 
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Re: How the 737 MAX 10 landing gear works

Thu Aug 30, 2018 11:39 pm

FriscoHeavy wrote:
Ruscoe wrote:
Last I heard, not official, the 737-10 MTOW was 92,000kg. Last time I looked, for comparison, MTOW of the 737-9 was 88,300kg.

Ruscoe


What is that in pounds? We use pounds/lbs here, so it would be nice for people to post weights for planes built in America to be given in pounds as well.



202,825lbs. The Max-9 is 194,700 pounds.

In theory a Max-9 with the Max-10's MTOW should be able to carry an addition hour's worth of fuel. 4200nm~ with the same load. Reduced config of 170~ pax in the ball park of 4500nm with 4 ACT's.
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Ruscoe
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Joined: Sun Aug 22, 1999 5:41 pm

Re: How the 737 MAX 10 landing gear works

Fri Aug 31, 2018 12:02 am

It's interesting how the MTOW of each variant goes up over time, so one could expect another 10% or so for that 737-10 gear to handle. (by the way, interesting, but off topic , the weight of the 10 will be more than double that of the original 737-100 which had a MTOW of 44,000kg). 1kg ~~ 2.2 lbs;
 
Ruscoe
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Joined: Sun Aug 22, 1999 5:41 pm

Re: How the 737 MAX 10 landing gear works

Fri Aug 31, 2018 12:20 am

92,000 x 2.2 =202,400 lbs so would be very interesting to see the details of 727 (202,825) gear

Ruscoe
 
Samrnpage
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Re: How the 737 MAX 10 landing gear works

Fri Aug 31, 2018 12:23 am

Wow, its uninspiring. This proves the Max-10 is it for the 737 frame. It makes me believe the "797" will be a NSA but with family members that go past the A321 in capacity and range. It cannot not be right ?
 
trnswrld
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Re: How the 737 MAX 10 landing gear works

Fri Aug 31, 2018 12:25 am

Ruscoe wrote:
It's interesting how the MTOW of each variant goes up over time, so one could expect another 10% or so for that 737-10 gear to handle. (by the way, interesting, but off topic , the weight of the 10 will be more than double that of the original 737-100 which had a MTOW of 44,000kg). 1kg ~~ 2.2 lbs;


That's actually a really cool fact and impressive!
 
commpilot
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Re: How the 737 MAX 10 landing gear works

Fri Aug 31, 2018 12:36 am

Trailing Link with a slight modern twist during the retraction.
 
Okcflyer
Posts: 557
Joined: Sat May 23, 2015 11:10 pm

Re: How the 737 MAX 10 landing gear works

Fri Aug 31, 2018 1:19 am

Several interesting pieces here.

- Recall the Max10 only stretches 26” behind but 40” in front of wing.
- To rebalance weight distribution and prevent excessive downforce/drag from the tail, the pylons move the engines backwards a couple inches to help realigning COG.
- The 900 / 900ER traded ground stability for inflight drag reduction due to very close COG/COL. With the heavier LEAPs, this issued solved itself on the -9.
- The -10 wheel centers are behind the strut, meaning it trails compares to standard by a handful of inches. This will help on-ground stability without sacrificing in-air balance. These couple of inches also help tail clearance before upward translation. However, the upward translation also move the wheel center point forward which cancels much of effect but it’s only after some lift, which mean the rotation had already started at the further-aft point. It’s amazing that only a net height gain of 9” is all that was needed to get to Max9 level of runway performance.
- Weight and thrust will be interesting. Due to the increased moment loading due to the longer / trailing gear, I think it’s safe to assume the gear mount in the wingbox needed stiffening. Thing is, the original Max family would have left some design margin to improve probability of passing tests. Armed with the actual test data, the structural model should be more tuned and perhaps very new little was actually needed and most came from the spare capacity. Loads will have been recalibrated from the engine move and higher thrust anyway.
- It’ll be interesting if this modified wingbox become production standard for the rest of the series or remains specific to the -10 type. If becomes production standard, the Max9 could become a decent mid-haul platform.
- Recall exit slide limitations require the gear to collapse to standard height on the ground, otherwise expensive exit redesigned would have been needed. This, to me, is the very innovative piece of this challenge. Fit same wheel well. Be same height on ground. Extend only during critical rotation phase. Elegant!
Last edited by Okcflyer on Fri Aug 31, 2018 1:29 am, edited 1 time in total.

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