smartcooky
Penultimate Amazing
Revised post: Another Boeing head rolls
Fixed
Fixed
And they're back in the air. (Or at least they are cleared to be. Sort of.)
From: BBC
US safety regulators have cleared Boeing's 737 Max plane to fly again...Existing aircraft will need to be modified before going back into service, with changes to their design. Safety regulator, the US Federal Aviation Administration (FAA), said the clearance would not allow the plane to "return immediately" to the skies. Alongside the software and wiring changes, pilots will also need training.
True. But I suspect some of that might be along the lines of "Its been over a year since you've been flying... you need to log at least a few hours in the cockpit before you can fly again".Which is what they were trying to avoid.And they're back in the air. (Or at least they are cleared to be. Sort of.)
From: BBC
US safety regulators have cleared Boeing's 737 Max plane to fly again......Alongside the software and wiring changes, pilots will also need training.
True. But I suspect some of that might be along the lines of "Its been over a year since you've been flying... you need to log at least a few hours in the cockpit before you can fly again".
And even if there is some additional skills they have to learn, it will still be easier to train a pilot how to handle the changes to the MCAS system rather than on how to handle all new flight characteristics of a new plane and/or how the plane handles without MCAS.
Uh, no. No pilots were grounded (ETA: At least not by 737 Max, Covid is another story).True. But I suspect some of that might be along the lines of "Its been over a year since you've been flying... you need to log at least a few hours in the cockpit before you can fly again".
Nope. Some airlines might be able to get it back in service by the end of the year, although I think most are looking at early to mid 2021 before they actually start flying.And by "sort of" you mean "not actually back in the air at all".
Nope. Some airlines might be able to get it back in service by the end of the year, although I think most are looking at early to mid 2021 before they actually start flying.
Of course, not only has boeing run into troubles over safety concerns with the 737, they are also dealing with an aviation industry that is dealing with Covid19.
Which is what they were trying to avoid.
The only thing that disturbs me about this is that there doesn't seem to be a lot of transparency about the details of the requirements for return to flight. All I can see to find is this;
- The optional cockpit AoA sensor alert is now standard on all aircraft
- An MCAS software update allows the pilot to regain control more easily
- MCAS AoA input compares data from both sensors.
This is not detailed enough for my liking. With the FAA and Boeing both responsible for the crashes and incidents, I'd like to see an entirely independent review of the process and changes. I don't trust the FAA yet, and I certainly do not trust Boeing.
True. But I suspect some of that might be along the lines of "Its been over a year since you've been flying... you need to log at least a few hours in the cockpit before you can fly again".
And even if there is some additional skills they have to learn, it will still be easier to train a pilot how to handle the changes to the MCAS system rather than on how to handle all new flight characteristics of a new plane and/or how the plane handles without MCAS.
Uh, no. No pilots were grounded (ETA: At least not by 737 Max, Covid is another story).
Read back through the conversation and think about the issue we are addressing here. One of Boeing's goals was to avoid considering this plane to be a different type. They wanted to get away with an amended type rather than an entirely new type certificate. That's what smartcooky was addressing, that Boeing has now failed to avoid the need for type training.To carry passengers in the USA, a pilot has to make 3 take offs and landings in an aircraft of the same category, class, and type in the last 90 days.
Read back through the conversation and think about the issue we are addressing here. One of Boeing's goals was to avoid considering this plane to be a different type. They wanted to get away with an amended type rather than an entirely new type certificate. That's what smartcooky was addressing, that Boeing has now failed to avoid the need for type training.
And besides, read what Segnosaur said: "Its been over a year since you've been flying..." No, it hasn't. (ETA: By Boeing's original goal for the 737 Max, pilots have been flying that type continuously for a long time now)
This training requirement is not what Segnosaur said, it's something more along the lines of what smartcooky is saying, a recognition that this plane is different enough to require specialized training of some kind. It is not that the pilots themselves are rusty.
Indeed.
To review (for other readers) the Max 8 is aerodynamically different from previous 747 models. This difference is caused by the positioning of the engines further forwards and upwards*, the result of which is that under high power settings (especially during take off and climb-out), the aircraft has a tendency to pitch up. Such a situation would mean that pilots flying the previous 737 models would have to re-certify to fly the Max 8; a very expensive exercise involving training and an simulator time.
The whole rationale for MCAS in the first place was to make the Max 8 fly like other 737s, by using software to pitch the nose down on those situations mentioned above, so that the aircraft would respond identically, i.e. would have the same look and feel, thereby avoiding pilot re-certification, and allowing Boeing to offer airlines the Max 8 as a direct replacement/supplement for their existing 737 fleet.
Essentially, Boeing tried to cheapskate their way to making sales, and got burned... and 346 people paid for it with their lives.
* The reasons for this change in engine position is another fascinating story in itself.
I will gladly defer to anyone with more experience with aviation.And???? That's one of the first questions that came to mind, why move the engines? Surely there was a good (enough) reason to do so, right? Right?
I will gladly defer to anyone with more experience with aviation.
But, from what I understand, newer, more efficient engines tend to be wider/shorter than their older counterparts. (If you look at a picture of the earlier 737-100 and 200, the engines are narrower and longer, and go all the way under the wing.) The new engines simply wouldn't have enough ground clearance if they tried to mount them under the wings in the same configuration.
See: Wikipedia
And???? That's one of the first questions that came to mind, why move the engines? Surely there was a good (enough) reason to do so, right? Right?
And if they can get these things in the air again, who's going to want to ride in one.
Fun throughout but relevant at 3:05
Carlin, NSFW, obviously.
I will gladly defer to anyone with more experience with aviation.
But, from what I understand, newer, more efficient engines tend to be wider/shorter than their older counterparts. (If you look at a picture of the earlier 737-100 and 200, the engines are narrower and longer, and go all the way under the wing.) The new engines simply wouldn't have enough ground clearance if they tried to mount them under the wings in the same configuration.
See: Wikipedia
Its called a high-bypass geared turbofan. As you say, the intakes are wider and deeper and there is simply no room to fit them under the wings of the 737. The gearing of the fan lowers the fan rotation speed, and that lower fan speed allows a higher bypass ratio, which in turn leads to reduced fuel consumption and less jet noise noise.
Here is a video about why the two Max 8's crashed, but I have queued up to a brief, 90 sec explanation of why the engines were moved up.
https://youtu.be/H2tuKiiznsY?t=103
And if they can get these things in the air again, who's going to want to ride in one.[/SIZE]
Not 100% sure about this, but I recall reading that even if it had been technically feasible, it would still have an enormous economic disadvantage in the marketplace. If the ground clearance changes, that plane would not be compatible with other 737 luggage loading equipment or require a unique protocol on existing equipment. Much like the training issue, the cost of the plane alone isn't the whole story on how good of a "deal" it is.Not geared, butGE'sCFM's competitor for P&W's GTF, the LEAP-1B. Otherwise, basically correct. Higher bypass ratios lead to greater efficiency, but also to bigger fans. This has been a problem for Boeing since the 737-300, because the airplane sits so low to the ground. Hence the flattened bottom of the nacelle on the -300 through -900.
The LEAP was enough bigger that this was no longer enough, so the engine had to be moved forward to enable it to be moved up. Changing the flight characteristics of the airplane.
Raising the airplane wasn't practical because even as short as they are, the main landing gear "legs" bring the wheels almost completely together when retracted and even then the wheels don't make it completely into the wheel well. You can see the outboard tires protruding through (with an aero hubcap) when one flies over.
What's been needed for quite a long time is an actual replacement. Which I was working on there 15 years ago and still has not been able to make the "business case" work.
Not geared, butGE'sCFM's competitor for P&W's GTF, the LEAP-1B.
<snip>
What's been needed for quite a long time is an actual replacement. Which I was working on there 15 years ago and still has not been able to make the "business case" work.
American Airlines seems to be rather eager to get the 737Max back in service.
I would say "I can only hope they get bankrupt, since there is no other way they would get punished for killing 600+ people"...
...but I realized those actually responsible would simply fall on gold parachutes into high positions in other companies. Only ones that would get screwed would be lowly grunts, as usual.
Yay capitalism.
No wonder common historical recourse is of "Rich. Tree. Rope. Some assembly required." variety.
Still a better love story than Twilight.
Are you always that butthurt when someone comments about certain economic system (with serious unaddressed problems) that is not as good as beneficiaries of said system think? : rolleyes :
I agree that they have a large investment in the 737 Max, and it makes sense they would want to use them. But, they also have to deal with public perception of the plane, and saving money on operating a fleet of 737Maxes may not help much if it scares away potential customers.If my business depended on recouping such a major capital investment, I'd want it back in service as soon as I responsibly could, too.American Airlines seems to be rather eager to get the 737Max back in service.
I don't think most passengers even know what aircraft type they are on. And if they look at the seat pocket information card, it'll say 737-8 so they'll feel safe that they aren't on a Max.
I always know what make and model of airliner I will be flying on. When I go to the USA next year (Covid permitting) I will be making sure that I won't be flying on a Max, because I have zero confidence that Boeing can get this right.
Not sure if the proper question for this assertion is "over what period of time" or "did you forget to put a negative sign on that number"?Airline profit margins are about 9%.
Not sure if the proper question for this assertion is "over what period of time" or "did you forget to put a negative sign on that number"?
So, where did you get that number?
I find less than that and only reported for pre-Covid years. This year is likely to be negative and on obviously reduced revenue.
https://www.ainonline.com/aviation-...again-cuts-airline-profitability-outlook-2019
Not sure why you're reacting poorly to this. You used present tense phrasing for your ballpark estimate. And it seems to be way optimistic for the present. Probably on the wrong side of zero. That seems significant enough to point out. And now that I know how you got that number it also now seems reasonable to make the observation that citing recent pre-2020 numbers and or projections from that time frame isn't going to work. Covid knocked those numbers and projections off the rails.
And when I asked I didn't know that you were wrong*. There are competing things going on here. Revenue is way down. But airlines are also contracting their schedules in response to that. It's possible they could still manage to maintain a positive profit margin but on reduced revenues if they respond properly. That would have been an interesting and positive thing to have heard if it was the case.
* Don't actually know that your number is wrong for this year yet, but I'd bet against it. That's likely to be a dream number for a while.