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leghorn
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Does a 737 Max 10 really need MCAS?

Sat Jan 04, 2020 6:59 pm

Irrespective of whether it will be fitted or not does a 737 Max-10 need MCAS or does the length of the fuselage compensate enough to make it handle similar to previous 737 versions.
 
sevenair
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Re: Does a 737 Max 10 really need MCAS?

Sat Jan 04, 2020 7:18 pm

If it didn't then I'd guess Boeing would remove it and get it flying. At least then some of the 737 MAXs could fly. As it stands MCAS is required and therefore grounding is appropriate.
 
mcdu
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Re: Does a 737 Max 10 really need MCAS?

Sat Jan 04, 2020 7:32 pm

sevenair wrote:
If it didn't then I'd guess Boeing would remove it and get it flying. At least then some of the 737 MAXs could fly. As it stands MCAS is required and therefore grounding is appropriate.



Have been told by more than one person the max10 does not have MCAS. But would Boeing really say if it did or didn’t? Maybe since Mark Forkner is no longer at Boeing telling lies to the Feds, then maybe there is some truth to the rumor.
 
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ikolkyo
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Re: Does a 737 Max 10 really need MCAS?

Sat Jan 04, 2020 7:39 pm

I don’t think anybody actually knows the answer. I’d honestly just assume it does until told otherwise.
 
weekendppl
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Re: Does a 737 Max 10 really need MCAS?

Sat Jan 04, 2020 7:45 pm

They haven't flown it yet. All they have is modeling and simulation results to tell them one way or the other. The nacelles, presumably, have the same aero characteristics as they do on the Max8 and Max9, so, presumably, generate the same lift component at the same offset from CG at the same AoAs and airspeeds.
 
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Stitch
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Re: Does a 737 Max 10 really need MCAS?

Sat Jan 04, 2020 7:59 pm

BoeingGuy said all of the family models have MCAS and his source is the Boeing CSID (Crew Systems Interface Document) for the MAX family.

Avgeek21 stated that the MAX-10 would not have it and never intended to have it, but did not clarify his source beyond it being "inside Boeing".

Whether it has it or not is irrelevant to its airworthiness since MCAS is just one of the things that will need to be addressed before the MAX's Type Certificate is restored and any MAX family member can return to revenue service.
 
leghorn
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Re: Does a 737 Max 10 really need MCAS?

Sat Jan 04, 2020 8:00 pm

max-10 is over 4 metres longer. The horizontal stabilizers and rudder should be over 2 metres further back.
 
Antarius
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Re: Does a 737 Max 10 really need MCAS?

Sat Jan 04, 2020 8:38 pm

MAX10 is also taller, which may negate the need for MCAS.

Honestly, it is unknown. And Boeing has a giant cockup to fix and hundreds of grounded existing planes to fix before switching focus.
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Palop
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Re: Does a 737 Max 10 really need MCAS?

Sat Jan 04, 2020 8:57 pm

Antarius wrote:
MAX10 is also taller, which may negate the need for MCAS.


This needs to be clarified. How is the Max10 taller?
And if it is taller, how would it change the need for MCAS?
 
Antarius
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Re: Does a 737 Max 10 really need MCAS?

Sat Jan 04, 2020 9:08 pm

Palop wrote:
Antarius wrote:
MAX10 is also taller, which may negate the need for MCAS.


This needs to be clarified. How is the Max10 taller?
And if it is taller, how would it change the need for MCAS?


Here is an article explaining it better than I can
https://www.flightglobal.com/airframers ... 86.article

It has a taller gear due to the longer fuselage needing more clearance to avoid tail strikes. As a result, the engines potentially would not need to be pushed forward, thereby negating the need for MCAS - this is just a theory based on the gear and length of the aircraft though, it may still need MCAS for something else.
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ikolkyo
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Re: Does a 737 Max 10 really need MCAS?

Sat Jan 04, 2020 9:11 pm

Antarius wrote:
Palop wrote:
Antarius wrote:
MAX10 is also taller, which may negate the need for MCAS.


This needs to be clarified. How is the Max10 taller?
And if it is taller, how would it change the need for MCAS?


Here is an article explaining it better than I can
https://www.flightglobal.com/airframers ... 86.article

It has a taller gear due to the longer fuselage needing more clearance to avoid tail strikes. As a result, the engines potentially would not need to be pushed forward, thereby negating the need for MCAS - this is just a theory based on the gear and length of the aircraft though, it may still need MCAS for something else.


It’s only taller on rotation and landing, on the ground it sits the same as the rest of the family.
 
VSMUT
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Re: Does a 737 Max 10 really need MCAS?

Sat Jan 04, 2020 9:17 pm

Antarius wrote:
Palop wrote:
Antarius wrote:
MAX10 is also taller, which may negate the need for MCAS.


This needs to be clarified. How is the Max10 taller?
And if it is taller, how would it change the need for MCAS?


Here is an article explaining it better than I can
https://www.flightglobal.com/airframers ... 86.article

It has a taller gear due to the longer fuselage needing more clearance to avoid tail strikes. As a result, the engines potentially would not need to be pushed forward, thereby negating the need for MCAS - this is just a theory based on the gear and length of the aircraft though, it may still need MCAS for something else.


1. It sits at the same height on the ground. It is the rotation angle that has been changed slighty.
2. The issues that required MCAS pop up in flight, not on the ground.
 
Palop
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Re: Does a 737 Max 10 really need MCAS?

Sat Jan 04, 2020 9:22 pm

Antarius wrote:
Palop wrote:
Antarius wrote:
MAX10 is also taller, which may negate the need for MCAS.


This needs to be clarified. How is the Max10 taller?
And if it is taller, how would it change the need for MCAS?


Here is an article explaining it better than I can
https://www.flightglobal.com/airframers ... 86.article

It has a taller gear due to the longer fuselage needing more clearance to avoid tail strikes. As a result, the engines potentially would not need to be pushed forward, thereby negating the need for MCAS - this is just a theory based on the gear and length of the aircraft though, it may still need MCAS for something else.

According to that explanation, the landing gear extends 241 mm when the plane is about to do the rotation when taking off. This is to avoid tail strikes and/or excessive runway requirements.
However at standstill, taxiing and run up before takeoff the landing gear has the same length as before. Thus, you cannot push the engines down and back.
Remember one of the limits on the landing gear length is that there is a max height from the wings down as there are no slides on the overwing exits. This is why thr exotic landing gear that only telescopes and extends just prior to the takeoff rotation.
So the max10 landing gear does not help with the MCAS predicament
 
sevenair
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Re: Does a 737 Max 10 really need MCAS?

Sat Jan 04, 2020 9:26 pm

mcdu wrote:
sevenair wrote:
If it didn't then I'd guess Boeing would remove it and get it flying. At least then some of the 737 MAXs could fly. As it stands MCAS is required and therefore grounding is appropriate.



Have been told by more than one person the max10 does not have MCAS. But would Boeing really say if it did or didn’t? Maybe since Mark Forkner is no longer at Boeing telling lies to the Feds, then maybe there is some truth to the rumor.


ABSOLUTELY. For once I'd expect Boeing to be totally open and honest about MCAS.

I keep hearing it does but then I hear it doesn't have MCAS. Given that MCAS is the cause of two catastrophes and that the -10 is still grounded certainly gives credit to the theory of the version having MCAS.
 
leghorn
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Re: Does a 737 Max 10 really need MCAS?

Sat Jan 04, 2020 9:30 pm

sevenair wrote:
I keep hearing it does but then I hear it doesn't have MCAS. Given that MCAS is the cause of two catastrophes and that the -10 is still grounded certainly gives credit to the theory of the version having MCAS.

A simpler explanation might be that the plane doesn't have the problem but their limited resources need to be first assigned to the airframe that has already been released and was in service and for which there are thousands of hard orders.
It could be a case that the Max10 won't have these problems and Boeing would only give that plane to customers instead of a Max8 in desparation should no other solution be approved.
 
Antarius
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Re: Does a 737 Max 10 really need MCAS?

Sat Jan 04, 2020 9:48 pm

Palop wrote:
Antarius wrote:
Palop wrote:

This needs to be clarified. How is the Max10 taller?
And if it is taller, how would it change the need for MCAS?


Here is an article explaining it better than I can
https://www.flightglobal.com/airframers ... 86.article

It has a taller gear due to the longer fuselage needing more clearance to avoid tail strikes. As a result, the engines potentially would not need to be pushed forward, thereby negating the need for MCAS - this is just a theory based on the gear and length of the aircraft though, it may still need MCAS for something else.

According to that explanation, the landing gear extends 241 mm when the plane is about to do the rotation when taking off. This is to avoid tail strikes and/or excessive runway requirements.
However at standstill, taxiing and run up before takeoff the landing gear has the same length as before. Thus, you cannot push the engines down and back.
Remember one of the limits on the landing gear length is that there is a max height from the wings down as there are no slides on the overwing exits. This is why thr exotic landing gear that only telescopes and extends just prior to the takeoff rotation.
So the max10 landing gear does not help with the MCAS predicament


Yes. I misunderstood the at-rest position. Thanks (and to the posters above as well).
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Stitch
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Re: Does a 737 Max 10 really need MCAS?

Sat Jan 04, 2020 10:40 pm

sevenair wrote:
Given that MCAS is the cause of two catastrophes and that the -10 is still grounded certainly gives credit to the theory of the version having MCAS.


The 737-10 is still in flight test and certification so it's not like any frame would be in revenue service with a customer even if the family was not grounded, so the presence or lack of presence of MCAS would not matter at this point.

We also know that the investigation has raised other issues with the MAX and the regulatory authorities are likely going to want those addressed before they restore the Type Certificate. So once the 737-10 is ready to be delivered to customer airlines, if the TC has not yet been restored, then it's not going to fly, MCAS or no MCAS.
 
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LAX772LR
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Re: Does a 737 Max 10 really need MCAS?

Sat Jan 04, 2020 10:56 pm

sevenair wrote:
Given that MCAS is the cause of two catastrophes and that the -10 is still grounded certainly gives credit to the theory of the version having MCAS.

Not really.

Unlike the other two versions, the -10 was never certified to fly. So even if it doesn't/didn't/never had MCAS, and was never intended to, it'd still have to go through the certification process.

And right now, Boeing logically seems far more concerned with getting the two previously-certified models, for whom there are far more orders (not to mention compensatory requirements) back; than with getting something that's never been certified, in the air.
I myself, suspect a more prosaic motive... ~Thranduil
 
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zkojq
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Re: Does a 737 Max 10 really need MCAS?

Sun Jan 05, 2020 12:17 am

Antarius wrote:
It has a taller gear due to the longer fuselage needing more clearance to avoid tail strikes. As a result, the engines potentially would not need to be pushed forward, thereby negating the need for MCAS - this is just a theory based on the gear and length of the aircraft though, it may still need MCAS for something else.


If you're changing the engine placement, you'll need to design a new pylon which will be very expensive.
First to fly the 787-9
 
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Francoflier
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Re: Does a 737 Max 10 really need MCAS?

Sun Jan 05, 2020 1:26 am

I can't see why a longer fuselage would negate the need for MCAS.

The nacelle lift is still there at high AOA, therefore the pitch up moment and lightening of control forces would still be present then.
The higher effectiveness of the controls surfaces in the back might make this lightening much less pronounced however, meaning that it might only need a less agressive action from MCAS.

Unless there is a threshold under which the lightening becomes weak enough that it passes the requirement, but it's not my understanding of the regulation.
I'll do my own airline. With Blackjack. And hookers. In fact, forget the airline.
 
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Aesma
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Re: Does a 737 Max 10 really need MCAS?

Sun Jan 05, 2020 1:49 am

Yes, keep in mind MCAS is as much there to do something for safety, as it is there to make the MAX feel like an NG. So if the 10 is acting differently, it's not really a good thing for Boeing, they want it to act just like the other models.
New Technology is the name we give to stuff that doesn't work yet. Douglas Adams
 
FluidFlow
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Re: Does a 737 Max 10 really need MCAS?

Sun Jan 05, 2020 3:55 am

Why not certify the -10 as an independent type from the -8/9 and get over all the trouble at the cost of a different pilot pool.
 
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Stitch
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Re: Does a 737 Max 10 really need MCAS?

Sun Jan 05, 2020 4:30 am

FluidFlow wrote:
Why not certify the -10 as an independent type from the -8/9 and get over all the trouble at the cost of a different pilot pool.


It cannot be certified except under an amendment to the existing 737 Type Certificate as it leverages systems and such that would not be allowed on a new type under current regulations.
 
weekendppl
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Re: Does a 737 Max 10 really need MCAS?

Sun Jan 05, 2020 4:54 am

FluidFlow wrote:
Why not certify the -10 as an independent type from the -8/9 and get over all the trouble at the cost of a different pilot pool.

Because then they have to start over as if clean sheet and lots of things that get grandfathered from the original 737 type certificate no longer get grandfathered. The pilot pool could even be the same if they flew the same. But any FAR changes from 1965 or so on that didn't apply to derivatives of existing types (i.e., the 737 Classic, NG, MAX...) would apply to design and certification of such an "independent type". This problem is a major part of why the 737 MAX is the 737 MAX, not a 797... (And an A320 NEO is an A320 NEO for that matter.)
 
TheWorm123
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Re: Does a 737 Max 10 really need MCAS?

Sun Jan 05, 2020 7:12 am

Stitch wrote:
FluidFlow wrote:
Why not certify the -10 as an independent type from the -8/9 and get over all the trouble at the cost of a different pilot pool.


It cannot be certified except under an amendment to the existing 737 Type Certificate as it leverages systems and such that would not be allowed on a new type under current regulations.

Out of curiosity, what are examples of systems on the 737 that wouldn’t pass modern scrutiny on new types in 2020?
B752 B753 A332 A321 B738
 
mdavies06
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Re: Does a 737 Max 10 really need MCAS?

Sun Jan 05, 2020 7:42 am

viewtopic.php?t=1422939

viewtopic.php?t=1424433

Here are some threads on the same topic last year
 
kalvado
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Re: Does a 737 Max 10 really need MCAS?

Sun Jan 05, 2020 9:51 am

Stitch wrote:
sevenair wrote:
Given that MCAS is the cause of two catastrophes and that the -10 is still grounded certainly gives credit to the theory of the version having MCAS.


The 737-10 is still in flight test and certification so it's not like any frame would be in revenue service with a customer even if the family was not grounded, so the presence or lack of presence of MCAS would not matter at this point.

We also know that the investigation has raised other issues with the MAX and the regulatory authorities are likely going to want those addressed before they restore the Type Certificate. So once the 737-10 is ready to be delivered to customer airlines, if the TC has not yet been restored, then it's not going to fly, MCAS or no MCAS.

I think a better question to ask is of max10 can be considered as mcas-free (if it is) separate subtype, derived from ng, not as part of the -8 -9 family.
Other issues such as rudder cables would still be the same, and as we don't know what keeps max grounded - this is not a sure fire approach.
 
mcdu
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Re: Does a 737 Max 10 really need MCAS?

Sun Jan 05, 2020 12:47 pm

sevenair wrote:
mcdu wrote:
sevenair wrote:
If it didn't then I'd guess Boeing would remove it and get it flying. At least then some of the 737 MAXs could fly. As it stands MCAS is required and therefore grounding is appropriate.



Have been told by more than one person the max10 does not have MCAS. But would Boeing really say if it did or didn’t? Maybe since Mark Forkner is no longer at Boeing telling lies to the Feds, then maybe there is some truth to the rumor.


ABSOLUTELY. For once I'd expect Boeing to be totally open and honest about MCAS.

I keep hearing it does but then I hear it doesn't have MCAS. Given that MCAS is the cause of two catastrophes and that the -10 is still grounded certainly gives credit to the theory of the version having MCAS.


The -10 was just rolled out a few weeks ago. Not sure it’s first flight ready with or without MCAS
 
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JetBuddy
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Re: Does a 737 Max 10 really need MCAS?

Sun Jan 05, 2020 3:07 pm

TheWorm123 wrote:
Stitch wrote:
FluidFlow wrote:
Why not certify the -10 as an independent type from the -8/9 and get over all the trouble at the cost of a different pilot pool.


It cannot be certified except under an amendment to the existing 737 Type Certificate as it leverages systems and such that would not be allowed on a new type under current regulations.

Out of curiosity, what are examples of systems on the 737 that wouldn’t pass modern scrutiny on new types in 2020?


The whole aircraft is based on 50s/60s architecture that originated with the 707 and 727. It would be like taking a 60s Ford F-150, installing a new engine and updating the instruments, and trying to certify it as a brand new car.

Some of the things that would not pass muster:

- Doors are too small
- Aircraft sits too low
- Seats / cabin floor G-forces rating
- Archaic cables & pulleys flight control system
- No EICAS

.. and probably a bunch of other things.
 
Blockplus
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Re: Does a 737 Max 10 really need MCAS?

Sun Jan 05, 2020 3:17 pm

Originally we were told MCAS was put put on to make the plane feel like an ng would during certain cg/weight/speed parameters. If so why not just have the elevator feel computer just make the controls heavier. Or place strakes under the tail?
 
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hOMSaR
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Re: Does a 737 Max 10 really need MCAS?

Sun Jan 05, 2020 3:18 pm

Blockplus wrote:
Originally we were told MCAS was put put on to make the plane feel like an ng would during certain cg/weight/speed parameters. If so why not just have the elevator feel computer just make the controls heavier. Or place strakes under the tail?


What elevator feel computer?
I was raised by a cup of coffee.
 
kalvado
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Re: Does a 737 Max 10 really need MCAS?

Sun Jan 05, 2020 3:21 pm

hOMSaR wrote:
Blockplus wrote:
Originally we were told MCAS was put put on to make the plane feel like an ng would during certain cg/weight/speed parameters. If so why not just have the elevator feel computer just make the controls heavier. Or place strakes under the tail?


What elevator feel computer?

NG has simulated stick force, which is provided by hydraulic computer based on airspeed, elevator AoA etc. There is even a separate pitot tube on vertical stabilizer for that
 
TheWorm123
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Re: Does a 737 Max 10 really need MCAS?

Sun Jan 05, 2020 3:58 pm

JetBuddy wrote:
TheWorm123 wrote:
Stitch wrote:

It cannot be certified except under an amendment to the existing 737 Type Certificate as it leverages systems and such that would not be allowed on a new type under current regulations.

Out of curiosity, what are examples of systems on the 737 that wouldn’t pass modern scrutiny on new types in 2020?


The whole aircraft is based on 50s/60s architecture that originated with the 707 and 727. It would be like taking a 60s Ford F-150, installing a new engine and updating the instruments, and trying to certify it as a brand new car.

Some of the things that would not pass muster:

- Doors are too small
- Aircraft sits too low
- Seats / cabin floor G-forces rating
- Archaic cables & pulleys flight control system
- No EICAS

.. and probably a bunch of other things.

Thank you, I’ve yet to fly a 737 but the design overall looks fairly aged when you compare the nose to more modern jets like the A320 or even the 757.
B752 B753 A332 A321 B738
 
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767333ER
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Re: Does a 737 Max 10 really need MCAS?

Sun Jan 05, 2020 4:15 pm

JetBuddy wrote:
TheWorm123 wrote:
Stitch wrote:

It cannot be certified except under an amendment to the existing 737 Type Certificate as it leverages systems and such that would not be allowed on a new type under current regulations.

Out of curiosity, what are examples of systems on the 737 that wouldn’t pass modern scrutiny on new types in 2020?


The whole aircraft is based on 50s/60s architecture that originated with the 707 and 727. It would be like taking a 60s Ford F-150, installing a new engine and updating the instruments, and trying to certify it as a brand new car.

Some of the things that would not pass muster:

- Doors are too small
- Aircraft sits too low
- Seats / cabin floor G-forces rating
- Archaic cables & pulleys flight control system
- No EICAS

.. and probably a bunch of other things.

IIf memory serves the doors also require too much force to open. The one thing they were not allowed to grandfather was the window exit design which is why the 737NG got those built in opening exits it has (the one good design on the plane).
Been on: 732 733 734 73G 738 752 763 A319 A320 A321 CRJ CR7 CRA/CR9 E145 E175 E190 F28 MD-82 MD-83 C172R C172S P2006T PA-28-180

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CALTECH
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Re: Does a 737 Max 10 really need MCAS?

Sun Jan 05, 2020 4:34 pm

mcdu wrote:
sevenair wrote:
If it didn't then I'd guess Boeing would remove it and get it flying. At least then some of the 737 MAXs could fly. As it stands MCAS is required and therefore grounding is appropriate.



Have been told by more than one person the max10 does not have MCAS. But would Boeing really say if it did or didn’t? Maybe since Mark Forkner is no longer at Boeing telling lies to the Feds, then maybe there is some truth to the rumor.


They all have it, according to the Boeing Manuals.....

737-7/8/8200/9/10

ALL

Maneuvering Characteristic Augmentation System (MCAS)

Image
You are here.
 
UpNAWAy
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Re: Does a 737 Max 10 really need MCAS?

Sun Jan 05, 2020 5:16 pm

To fly no, to certify as a common B737 yes.
 
Venatt
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Re: Does a 737 Max 10 really need MCAS?

Sun Jan 05, 2020 5:49 pm

Antarius wrote:
Palop wrote:
Antarius wrote:
MAX10 is also taller, which may negate the need for MCAS.


This needs to be clarified. How is the Max10 taller?
And if it is taller, how would it change the need for MCAS?


Here is an article explaining it better than I can
https://www.flightglobal.com/airframers ... 86.article

It has a taller gear due to the longer fuselage needing more clearance to avoid tail strikes. As a result, the engines potentially would not need to be pushed forward, thereby negating the need for MCAS - this is just a theory based on the gear and length of the aircraft though, it may still need MCAS for something else.



My main concern is what if the landing gear fails to extend while rotating and the plane is on the run way at high speed ?
 
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Stitch
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Re: Does a 737 Max 10 really need MCAS?

Sun Jan 05, 2020 6:12 pm

kalvado wrote:
I think a better question to ask is of max10 can be considered as mcas-free (if it is) separate subtype, derived from ng, not as part of the -8 -9 family.


I don't see how this would be possible since it is a MAX model and incorporates systems unique to the MAX and not found on the NG.


Venatt wrote:
My main concern is what if the landing gear fails to extend while rotating and the plane is on the run way at high speed ?


I believe the natural position for the strut is extended - it is the weight of the airframe pushing down on it on the ground that keeps it compressed. As the wings take the airframe weight load, the struts extend naturally. And when the plane lands and the wings shed the airframe weight load, the strut naturally compresses under the airframe weight. So they would always extend upon rotation.
 
kalvado
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Re: Does a 737 Max 10 really need MCAS?

Sun Jan 05, 2020 8:38 pm

Stitch wrote:
kalvado wrote:
I think a better question to ask is of max10 can be considered as mcas-free (if it is) separate subtype, derived from ng, not as part of the -8 -9 family.


I don't see how this would be possible since it is a MAX model and incorporates systems unique to the MAX and not found on the NG.


Venatt wrote:
My main concern is what if the landing gear fails to extend while rotating and the plane is on the run way at high speed ?


I believe the natural position for the strut is extended - it is the weight of the airframe pushing down on it on the ground that keeps it compressed. As the wings take the airframe weight load, the struts extend naturally. And when the plane lands and the wings shed the airframe weight load, the strut naturally compresses under the airframe weight. So they would always extend upon rotation.

Well, max is a modified NG for certification reasons. Can there be another subtype of 737, say Super, another flavor ofupgraded NG having just one model- formerly known as max10, without mcas and without but flip computer upgrade? Paperwork mess, but then super10 can be delivered before max rts
 
sxf24
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Re: Does a 737 Max 10 really need MCAS?

Sun Jan 05, 2020 10:39 pm

JetBuddy wrote:
TheWorm123 wrote:
Stitch wrote:

It cannot be certified except under an amendment to the existing 737 Type Certificate as it leverages systems and such that would not be allowed on a new type under current regulations.

Out of curiosity, what are examples of systems on the 737 that wouldn’t pass modern scrutiny on new types in 2020?


Some of the things that would not pass muster:

- Doors are too small
- Aircraft sits too low
- Seats / cabin floor G-forces rating
- Archaic cables & pulleys flight control system
- No EICAS

.. and probably a bunch of other things.


You have no clue what you’re talking about. None of those items are certification issues for the 737.
 
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CALTECH
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Joined: Thu May 17, 2007 4:21 am

Re: Does a 737 Max 10 really need MCAS?

Sun Jan 05, 2020 11:06 pm

Stitch wrote:
kalvado wrote:
I think a better question to ask is of max10 can be considered as mcas-free (if it is) separate subtype, derived from ng, not as part of the -8 -9 family.


I don't see how this would be possible since it is a MAX model and incorporates systems unique to the MAX and not found on the NG.


Venatt wrote:
My main concern is what if the landing gear fails to extend while rotating and the plane is on the run way at high speed ?


I believe the natural position for the strut is extended - it is the weight of the airframe pushing down on it on the ground that keeps it compressed. As the wings take the airframe weight load, the struts extend naturally. And when the plane lands and the wings shed the airframe weight load, the strut naturally compresses under the airframe weight. So they would always extend upon rotation.

https://www.boeing.com/features/2018/08 ... 08-18.page
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JetBuddy
Posts: 2578
Joined: Wed Dec 25, 2013 1:04 am

Re: Does a 737 Max 10 really need MCAS?

Mon Jan 06, 2020 1:09 am

sxf24 wrote:
JetBuddy wrote:
TheWorm123 wrote:
Out of curiosity, what are examples of systems on the 737 that wouldn’t pass modern scrutiny on new types in 2020?


Some of the things that would not pass muster:

- Doors are too small
- Aircraft sits too low
- Seats / cabin floor G-forces rating
- Archaic cables & pulleys flight control system
- No EICAS

.. and probably a bunch of other things.


You have no clue what you’re talking about. None of those items are certification issues for the 737.


Actually, you're the one who doesn't know what I'm talking about.

The question was what would be issues if the 737 were to be certified as a brand new aircraft today, without any grandfathering.

Next time, try reading the original question before posting.
 
sxf24
Posts: 1007
Joined: Wed Aug 15, 2007 12:22 pm

Re: Does a 737 Max 10 really need MCAS?

Mon Jan 06, 2020 1:19 am

JetBuddy wrote:
sxf24 wrote:
JetBuddy wrote:

Some of the things that would not pass muster:

- Doors are too small
- Aircraft sits too low
- Seats / cabin floor G-forces rating
- Archaic cables & pulleys flight control system
- No EICAS

.. and probably a bunch of other things.


You have no clue what you’re talking about. None of those items are certification issues for the 737.


Actually, you're the one who doesn't know what I'm talking about.

The question was what would be issues if the 737 were to be certified as a brand new aircraft today, without any grandfathering.

Next time, try reading the original question before posting.


The only item that could potentially be an issue is is EICAS.
 
planecane
Posts: 1585
Joined: Thu Feb 09, 2017 4:58 pm

Re: Does a 737 Max 10 really need MCAS?

Mon Jan 06, 2020 3:26 am

Blockplus wrote:
Originally we were told MCAS was put put on to make the plane feel like an ng would during certain cg/weight/speed parameters. If so why not just have the elevator feel computer just make the controls heavier. Or place strakes under the tail?


The EFC has no way to know what the AoA is. Also, it is a hydraulic computer. It can't run algorithms like MCAS.

They would have to design and certify a whole new EFC with new capabilities and architecture.

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