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Are the MAXs now in 'Parc Ferme'..?

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Are the MAXs now in 'Parc Ferme'..?

Old 31st Mar 2019, 18:21
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Are the MAXs now in 'Parc Ferme'..?

I just wonder if the grounded aircraft are in Parc Ferme, where they cannot be worked on by engineers.
If,.as has been suggested in other threads, there is some common AoA data transmission error. Then it would be nice is the fault could be found in some of the other Maxs. as the only two aircraft we know had the fault are not intact now.
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Old 31st Mar 2019, 18:30
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Originally Posted by scifi View Post
I just wonder if the grounded aircraft are in Parc Ferme, where they cannot be worked on by engineers.
What makes you think that?

They will be getting the same attention given to any aircraft that aren't going to fly again for a while.
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Old 1st Apr 2019, 11:49
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There are five Tui Max’s parked at Juliet 1 at Manchester, (making that intersection unavailable to traffic).

I would imagine that these aircraft can be worked on in the open to prepare them for short-term storage? Would they remove batteries, empty the fuel water drains and drain potable water? I am sure there is more to it than that. Maybe jack them onto blocks to prevent tyre flats?

They can change engines outside, (under a tent), so I would imagine they can work on Avionics and probes?
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Old 1st Apr 2019, 12:01
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TUI Max aircraft at TFS have had wheel bogies wrapped in plastic along with normal probe/engine covers
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Old 1st Apr 2019, 12:18
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I was thinking that they would be a good source of information, and that an engineer could un-knowingly alter any evidence that would help pin-point the faults.
Were there not a few other aircraft that had similar captain side anomalies. These should be inspected by suitable FAA / CAA teams.

Last edited by scifi; 1st Apr 2019 at 14:08.
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Old 1st Apr 2019, 15:05
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Originally Posted by scifi View Post
I was thinking that they would be a good source of information, and that an engineer could un-knowingly alter any evidence that would help pin-point the faults.
Were there not a few other aircraft that had similar captain side anomalies. These should be inspected by suitable FAA / CAA teams.
I had that same thought, to test them every day until an AOA error occurs, but politics/liability/insurance would all get in the way.
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Old 9th Apr 2019, 10:53
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Lets be quite honest, that airframe was never designed for those engines, and no amount of software is going to solve that problem.
If Boeing want to use the LEAF engines then they need to design a new aircraft to suit them.
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Old 9th Apr 2019, 13:30
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Originally Posted by scifi View Post
Lets be quite honest, that airframe was never designed for those engines, and no amount of software is going to solve that problem.
To be fair, it was never designed for the engines on the Classic or NG, either.
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Old 9th Apr 2019, 14:20
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Plenty of aircraft have been re-engined over the years not just the 737.
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Old 9th Apr 2019, 15:05
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Exup, its not just re-engining, it’s repositioning, wt, cg, and lift from the extended nacelles - proportional to AoA.

At least none have been sent to Tucson so far.
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Old 9th Apr 2019, 15:09
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Originally Posted by scifi View Post
Lets be quite honest, that airframe was never designed for those engines, and no amount of software is going to solve that problem.
If Boeing want to use the LEAF engines then they need to design a new aircraft to suit them.
Can we get some arguments to support this statement?
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Old 9th Apr 2019, 16:13
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Originally Posted by tttoon View Post
Can we get some arguments to support this statement?
Just look at the size of the engines on the 737-200 vs 737-Max. The fact that they need to flatten the bottom part of the engine nacelle on the NG says a lot already.
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Old 9th Apr 2019, 16:59
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Originally Posted by pineteam View Post
The fact that they need to flatten the bottom part of the engine nacelle on the NG says a lot already.
Even before the NG the nacelles were flattened, albeit not by quite so much, on the Classic.

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Old 10th Apr 2019, 00:00
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The B737 fuselage design dates back to the 1950s, the later designed B767/757 are already obsolete and except for a few specialised variants, out of production. It should have been obvious to Boeing back in the 1980s that they needed a new airframe for their bread and butter narrowbody. Possibly they didn't see the new A320 as a threat and weren't willing to invest the money in a new design. Even at 30 years old the A320 is still a fantastic aircraft which is still able to be updated without mutating it into something the original designer wouldn't recognise. New sharklet wings and next generation engines have improved it's efficiency considerably, update the flight deck and there is no reason for it not to go on for another 20 years.

Boeing would need to spend billions on a new design which would be unlikely to offer significant improvements over the current A320 series, and the selling price would need to recoup the development costs. Margins at the economy end of the market aren't as much as at the higher widebody long haul end and it would take many years to get back into the black.
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Old 10th Apr 2019, 06:49
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Originally Posted by krismiler View Post
Even at 30 years old the A320 is still a fantastic aircraft which is still able to be updated without mutating it into something the original designer wouldn't recognise. New sharklet wings and next generation engines have improved it's efficiency considerably, update the flight deck and there is no reason for it not to go on for another 20 years.

Boeing would need to spend billions on a new design which would be unlikely to offer significant improvements over the current A320 series
You can't have it both ways.

The A320 certainly has significant advantages over the 737, which is no surprise given that it came along 20 years later.

So what makes you think that an all-new aircraft 30 years further down the road than the A320 wouldn't be able to offer a corresponding leap over it in technology and capability ?
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Old 10th Apr 2019, 07:49
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I'm not a tube driver so could someone please explain to me why the 757 was ditched, especially the -100 in favour of the 737? Was it due to the 'same type' argument that seems to pervade for the 737 Max? It seems to me that this was a good aircraft with plenty of space for bigger engines.
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Old 10th Apr 2019, 07:59
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Originally Posted by Cows getting bigger View Post
I'm not a tube driver so could someone please explain to me why the 757 was ditched, especially the -100 in favour of the 737? Was it due to the 'same type' argument that seems to pervade for the 737 Max? It seems to me that this was a good aircraft with plenty of space for bigger engines.
Someone stated that the cost-per-seat-mile of the B757 was almost twice as high as the B737. Simple economics, airlines stopped buying it, end of story. Fuel efficiency is king in the low-cost market, and safety is a secondary concern, as long as the aircraft is FAA approved, and has a long flight history, and passengers are willing to step on board.
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Old 10th Apr 2019, 08:40
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You see, that's where I'm a bit confused. The only data I can find is that cost/seat mile for the latter 737s is in the region of 6-8 cents/mile; Boeing claim the Max is a 20% improvement on earlier models. The 757 appears to be about 7.5 cents/mile.

https://www.planestats.com/bhsn_2014sep

Wiki hits it from a different angle saying that a 737 Max has a Miles Per US Gallon of 102/seat with the 757-300 at 88 MPG.

For sure, the 757 appears to be more expensive but not in the order of twice as much. It would be an interesting theoretical exercise to number crunch a 757 with LEAF engines.
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Old 10th Apr 2019, 09:39
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Same TDC S269C and S269D

Nothing like a good engine change and pretty much all the air-frame - only thing similar is being able to continue to use the magnesium.
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Old 10th Apr 2019, 10:26
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Originally Posted by DaveReidUK View Post
You can't have it both ways.

The A320 certainly has significant advantages over the 737, which is no surprise given that it came along 20 years later.

So what makes you think that an all-new aircraft 30 years further down the road than the A320 wouldn't be able to offer a corresponding leap over it in technology and capability ?
It's a good question.

If Boeing can design an aircraft that offers superior safety / fly by wire characteristics / ergonomics to the A320 family of aircraft, they'd be on a winner.

Unfortunately for them, I think that technology has largely plateaued since the A320 introduction. The only major change is in engine efficiency. The 787 and A350 are certainly incremental improvements, but largely offer a refinement (albeit larger) of the A320 FBW concept.

For Boeing, shrinking the 787 into a new 737 replacement would need to do a lot more than the A320 to be a best seller. Size aside, the 787 and the A320 are largely equals in terms of technology and safety. If the tech was there, Boeing would have it on show already in the 787.
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