Sep 19, 2017, 10:25 am
Last edit by: 24left
Jan 18 2021 TC issues Airworthiness Directive for the 737 MAX
Link to post https://www.flyertalk.com/forum/32976892-post4096.html
Cabin photos
Post 976 https://www.flyertalk.com/forum/29534462-post976.html
Post 1300 https://www.flyertalk.com/forum/29780203-post1300.html
Cabin Layout
Interior Specs can be found here https://www.aircanada.com/ca/en/aco/home/fly/onboard/fleet.html
- Window seats may feel narrower to come as the armrests are placed "into" the "curvature" of the cabin.
- Seats with no windows feel even more narrower as there is no space created by the curvature of window.
- All bulkhead seats have very limited legroom.
- Seats 15A, 16A, 16F, 17A and 17F have limited windows.
- Exit rows 19 and 20 have more legroom than regular preferred seats.
Routes
The 737 MAX is designated to replace the A320-series. Based on announcements and schedule updates, the following specific routes will be operated by the 737 MAX in future:
YYZ-LAX (periodic flights)
YYZ-SNN (new route)
YUL-DUB (new route)
YYZ/YUL-KEF (replacing Rouge A319)
YYT-LHR (replacing Mainline A319)
YHZ-LHR (replacing Mainline B767)
Hawaii Routes YVR/YYC (replacing Rouge B767)
Many domestic trunk routes (YYZ, YVR, YUL, YYC) now operated by 7M8, replacing A320 family
Link to post https://www.flyertalk.com/forum/32976892-post4096.html
Cabin photos
Post 976 https://www.flyertalk.com/forum/29534462-post976.html
Post 1300 https://www.flyertalk.com/forum/29780203-post1300.html
Cabin Layout
Interior Specs can be found here https://www.aircanada.com/ca/en/aco/home/fly/onboard/fleet.html
- Window seats may feel narrower to come as the armrests are placed "into" the "curvature" of the cabin.
- Seats with no windows feel even more narrower as there is no space created by the curvature of window.
- All bulkhead seats have very limited legroom.
- Seats 15A, 16A, 16F, 17A and 17F have limited windows.
- Exit rows 19 and 20 have more legroom than regular preferred seats.
Routes
The 737 MAX is designated to replace the A320-series. Based on announcements and schedule updates, the following specific routes will be operated by the 737 MAX in future:
YYZ-LAX (periodic flights)
YYZ-SNN (new route)
YUL-DUB (new route)
YYZ/YUL-KEF (replacing Rouge A319)
YYT-LHR (replacing Mainline A319)
YHZ-LHR (replacing Mainline B767)
Hawaii Routes YVR/YYC (replacing Rouge B767)
Many domestic trunk routes (YYZ, YVR, YUL, YYC) now operated by 7M8, replacing A320 family
Air Canada Selects Boeing 737 MAX to Renew Mainline Narrowbody Fleet
Mar 19, 2019, 2:03 am
#2161
Suspended
Join Date: Mar 2014
Posts: 1,684
Depends upon what you think the FAA's role is.
Are they are there to oversee processes? To validate outcomes? If the latter by re-doing all the engineering, spot-checking, random inspection and analysis or some other variety of tests?
Unless the FAA repeats every last calculation and analysis there is always the possibility of a problem arising. There has to be a balance between trusting the manufacturer to have strong-enough internal processes and the FAA have deep, embedded oversight. Maybe there was just too much comfort both in Boeing and the FAA with the idea that it was a "737" and not digging deep enough into some of the assumptions around engineering and design choices that resulted in aerodynamic, weight distribution and thrust force complexities that combined to create unanticipated hazards to flight safety.
Are they are there to oversee processes? To validate outcomes? If the latter by re-doing all the engineering, spot-checking, random inspection and analysis or some other variety of tests?
Unless the FAA repeats every last calculation and analysis there is always the possibility of a problem arising. There has to be a balance between trusting the manufacturer to have strong-enough internal processes and the FAA have deep, embedded oversight. Maybe there was just too much comfort both in Boeing and the FAA with the idea that it was a "737" and not digging deep enough into some of the assumptions around engineering and design choices that resulted in aerodynamic, weight distribution and thrust force complexities that combined to create unanticipated hazards to flight safety.
Mar 19, 2019, 2:24 am
#2163
Join Date: Jan 2012
Programs: AC E50K, MM, BA, Delta, PriorityClub Platinum, Marriott Gold.
Posts: 468
It has more to do with budget cuts than comfort. You should feel glad that AC is dealing with it though. The MAX is a terribly uncomfortable plan and Boeing made the decision to keep going with technology from the 50's instead of making something equivalent to a Dreamliner.
Mar 19, 2019, 5:55 am
#2164
Join Date: Apr 2011
Location: YXU
Programs: AC SE100K, National E/E, HH Diamond, IHG Diamond, MB, Avis PC
Posts: 968
No, it measures the angle between the aircraft's reference line and the oncoming air flow. It is basically a small rotary wing with a position encoder. Can be combined with the Pitot and air temperature probe.
Mar 19, 2019, 6:40 am
#2165
Join Date: Apr 2011
Location: YYC
Programs: AC 50k 1MM, Marriott LT Titanium Elite
Posts: 3,400
Because while an aircraft is an enormously complex system at a point in time, a fleet of aircraft operating over years is an order of magnitude more complex.
Boeing is in a position to collect, process and disseminate operational details... If end users share data, anyway.
Boeing is in a position to collect, process and disseminate operational details... If end users share data, anyway.
Mar 19, 2019, 3:15 pm
#2166
FlyerTalk Evangelist
Join Date: Jun 2003
Location: YYC
Posts: 23,804
For better or worse, that has been the standard way to look at things for a long time, though. Just to give one example, about diesel engines, sub-micron particles, which cannot or at least could not be measured, for the longest time were assumed to be safe, even though clearly these could more easily get deeper into your lungs. How long did it take for us to figure out that they are actually the most damaging? I suspect you can make similar claims about a bunch of pesticides too. The attitude is now chan ging, but so far mostly in Europe, and more slowly on this side of the Atlantic, as the current issue shows.
Mar 19, 2019, 3:26 pm
#2167
Join Date: Dec 2006
Location: YEG
Posts: 3,925
My understanding of the situation is that the whole chain of dominoes for this started with the landing gear. Landing gears were too short to give sufficient clearance for larger engines under the wings, so engines had to be re-positioned, which caused the nose pitch issue that could have required a re-designed tail (or was it something else), but to avoid having to redesign that component Boeing came up with MCAS.
With hindsight being 20/20 I wonder if Boeing wished they'd simply redesigned the landing gears (and whatever additional certification hoops would have been jumped through for that).
With hindsight being 20/20 I wonder if Boeing wished they'd simply redesigned the landing gears (and whatever additional certification hoops would have been jumped through for that).
Mar 19, 2019, 3:27 pm
#2168
Join Date: Aug 2013
Location: YVR - MILLS Waypoint (It's the third house on the left)
Programs: AC*SE100K, wood level status in various other programs
Posts: 6,231
Well, they did make the landing gear longer.
Last edited by Bohemian1; Mar 19, 2019 at 3:28 pm Reason: And now with a hyperlink!
Mar 19, 2019, 3:37 pm
#2169
Join Date: Apr 2011
Location: YYC
Programs: AC 50k 1MM, Marriott LT Titanium Elite
Posts: 3,400
For better or worse, that has been the standard way to look at things for a long time, though. Just to give one example, about diesel engines, sub-micron particles, which cannot or at least could not be measured, for the longest time were assumed to be safe, even though clearly these could more easily get deeper into your lungs. How long did it take for us to figure out that they are actually the most damaging? I suspect you can make similar claims about a bunch of pesticides too. The attitude is now chan ging, but so far mostly in Europe, and more slowly on this side of the Atlantic, as the current issue shows.
Secondarily it it is very clear that if AC believed the plane to be totally safe they wouldn’t need to work with Boeing to ensure its safety. The press release they issued wasn’t logically sensible.
While your our points are noted I still think if directly asked the truthful answer about diesel particles would have been “we don’t know but we assume they are safe” not the affirmative “they are safe”. Certainly the latter is not scientifically accurate. And would t have been even if we didn’t know.
Mar 19, 2019, 3:37 pm
#2170
Join Date: Apr 2011
Location: YXU
Programs: AC SE100K, National E/E, HH Diamond, IHG Diamond, MB, Avis PC
Posts: 968
Well, they did make the landing gear longer.
Mar 19, 2019, 3:47 pm
#2171
Join Date: Apr 2011
Location: YXU
Programs: AC SE100K, National E/E, HH Diamond, IHG Diamond, MB, Avis PC
Posts: 968
My understanding of the situation is that the whole chain of dominoes for this started with the landing gear. Landing gears were too short to give sufficient clearance for larger engines under the wings, so engines had to be re-positioned, which caused the nose pitch issue that could have required a re-designed tail (or was it something else), but to avoid having to redesign that component Boeing came up with MCAS.
With hindsight being 20/20 I wonder if Boeing wished they'd simply redesigned the landing gears (and whatever additional certification hoops would have been jumped through for that).
With hindsight being 20/20 I wonder if Boeing wished they'd simply redesigned the landing gears (and whatever additional certification hoops would have been jumped through for that).
Mar 19, 2019, 4:11 pm
#2172
Join Date: Dec 2006
Location: YEG
Posts: 3,925
The problem is that the redesign wouldn't be so simple. The wing box would have to be redesigned. That would be expensive and would have an impact on certification. Also, it would probably necessitate slides on the wings. That's extra mass and would decrease the available fuel volume. Along with the extra mass of the longer landing gear it would most likely eliminate the slight range and economy edge the 737-800 had over the A320 (and perhaps the 737-8 has over the A320N?).
Mar 19, 2019, 4:39 pm
#2173
FlyerTalk Evangelist
Join Date: Jun 2003
Location: YYC
Posts: 23,804
My understanding of the situation is that the whole chain of dominoes for this started with the landing gear. Landing gears were too short to give sufficient clearance for larger engines under the wings, so engines had to be re-positioned, which caused the nose pitch issue that could have required a re-designed tail (or was it something else), but to avoid having to redesign that component Boeing came up with MCAS.
Actually what I posted a while ago was not quite correct. It's not the torque due to engine thrust that's the issue; in fact the engines being higher lowers the torque (which obviously a higher thrust increases it). However it turns out that the engines develop lift, and since they are further up front, the torque due to the lift is more than the horizontal stabilizer is able to counterbalance. Which points to a potentially better and cheaper solution compared with redesigning the tail: to redesign the shape of the engine cowling so as to reduce the lift to an acceptable value. Would likely be quite a bit cheaper, and since these are parts that get removed during engine maintenance, retrofit should be easy and likely doable by airline maintenance. Also, certification under the old type would presumably be kept. After all that would be a minor change on the engines. But of course, might take a year.
Mar 19, 2019, 5:03 pm
#2174
Join Date: Jan 2001
Programs: AC SEMM
Posts: 724
Actually what I posted a while ago was not quite correct. It's not the torque due to engine thrust that's the issue; in fact the engines being higher lowers the torque (which obviously a higher thrust increases it). However it turns out that the engines develop lift, and since they are further up front, the torque due to the lift is more than the horizontal stabilizer is able to counterbalance. Which points to a potentially better and cheaper solution compared with redesigning the tail: to redesign the shape of the engine cowling so as to reduce the lift to an acceptable value. Would likely be quite a bit cheaper, and since these are parts that get removed during engine maintenance, retrofit should be easy and likely doable by airline maintenance. Also, certification under the old type would presumably be kept. After all that would be a minor change on the engines. But of course, might take a year.
Mar 19, 2019, 5:11 pm
#2175
FlyerTalk Evangelist
Join Date: Jun 2003
Location: YYC
Posts: 23,804
I would be very surprised if this was not considered during the original development. I would hazard that the consequence of ruining the airflow over the cowling to limit lift in high angle of attack incidents would be reduced aerodynamics and thus fuel efficiency in normal flight.
If it would have been then surely they also would have found that the destabilizing torque was too high. I believe I read somewhere that the issue was discovered during flight tests. Unfortunately I don't remember where I read this so who knows...Of course you are correct that touching on the cowlings might have some impact on performance. But lowering lift does not necessarily mean "ruining the flow," and/or increasing drag, it's more an issue of upper shape vs. lower.