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Does anyone have a mirror of that video?

by lysp 8y ago

mhandley 8y ago
This was posted on PPrune: "Originally Posted by infrequentflyer789 Since this video may not be coming back I'll post a sort of transcript from memory since I was lucky enough to get to watch it. I'll try and just describe what I saw and keep my commentary/speculation to a minimum - in <italic>. Bear in mind this is a non-pilot observer's take on it from flaky memory: There is a fair bit of intro talk then the sim. They are in NG sim, not MAX, no surprise there. Mentour in left seat. They start at low altitude, I think it was commented on, not at takeoff, I can't remember if they showed putting flaps up or started with flaps up and said it was just after flaps up. No stick shaker, that I saw. <presume means no elevator feel shift either, and that actual AOA error is not being simulated> IAS disagree then simulated - or they just did the memory items, I didn't notice warning light (not that I would) and he didn't note it, there was an aural alarm but I think that was for AP disconnect <I don't think this is exactly what the accident flights faced, they had shaker and IAS disagree from takeoff> IAS disagree memory items, AP/AT OFF, FDs OFF, 75% N1, 4degrees Throttles are pushed forward to get 75%, he comments that at low alt with denser air this is a lot of thrust and hence speed will increase Trim runs, obviously sim doesn't have MCAS so not sure if they are simulating runaway or if he is doing it with the column switches Comment is made that he was _expecting_ trim to run, because speed is changing, he says it will take a couple of cycles of fighting it with the switches before being definite that it is wrong They discuss (he raises) that he is having flight control issue, they conclude it is trim that is the problem, they now run the stab trim runaway memory items finishing by hitting the switches. At this point he is clearly holding quite a bit of pressure on the column, but not obviously losing control of pitch Now he points out that trim has only got down to (I think) 3 degrees on the indicator (zero being full nose down, I think) and that they are now going to "try something" - video captions say "don't try this at home", like we've all got a FFS in our shed or a 737 on the drive :-) At this point the guy in the right seat uses the handle to wind the trim further _forward_. He stops when he clearly cannot wind it further - but they point out that it's still not at full nose down Mentour is obviously struggling to keep the nose up at this point. I noticed he didn't seem to have the shoulder straps on (right seat did), possibly because he was frequently turning round to talk to the camera. That probably didn't help, but on the other hand he didn't have stick shaker or feel shift to cope with either. Now, with Mentour pulling back, the right seat guy tries to wind the trim back with the handle - and he struggles to move it at all They stop the sim, I think it was after stopping that he noted that at that point they were at 310 (maybe he said 340) knots. I think there was then some further commentary, at one point I think he mentioned the rollercoaster to unload the stab and allow trimming, but commented that close to the ground the instinct is to pull back - I may be imagining that or remembering it from another video though. And that was about it. I can try to answer questions on the video if anyone has any. The eye-opener for me wasn't the force on the control column (which was held anyway), it was that the trim couldn't be moved, in either direction. From somewhere I had got the impression that those wheels had a lot of leverage, due to the gearing, which was why a lot of turns would be required, but it seems that a lot of turns would be required and a gorilla to make them..."
- CamperBob2 8y ago
  Since this video may not be coming back I'll post a sort of transcript from memory since I was lucky enough to get to watch it. I'll try and just describe what I saw and keep my commentary/speculation to a minimum - in <italic>. Bear in mind this is a non-pilot observer's take on it from flaky memory Was the video pulled? Who did that, and why?
  - mhandley 8y ago
    The speculation is that his employer, which flies a lot of 737s, didn't like him using a company simulator to illustrate a safety issue with the 737.
  - colde 8y ago
    He pulled it himself. https://twitter.com/MenTourPilot/status/1113723580284583936 https://twitter.com/MenTourPilot/status/1113723580284583936
    - jillesvangurp 8y ago
      His channel is worth following. He often posts insightful stuff related to incidents with 737s or just general information. He had a nice video about emergency procedures with a total engine failure in (probably) the same simulator just a few weeks ago.
- TheSpiceIsLife 8y ago
  Is anybody here capable of calculating the force required to move the trim tabs on a 737MAX at 310 knots at low altitude? I imagine at that speed there would be quite some force on the elevator and trim tabs.
  - mhandley 8y ago
    There's no trim tab on a 737 - the whole horizontal stabilizer is moved to trim the aircraft in pitch. Normally this is done electrically, but the stabilizer jackscrew can also be moved using manual trimwheels that move the jackscrew using physical cables. Whether this is possible at high airspeed while the stabilizer is trimmed nose down, and the elevator is being pulled up as hard as you can to avoid diving - that's the question that is being raised. Edit: this shows the jackscrew in operation: https://www.youtube.com/watch?v=rxPa9A-k2xY https://www.youtube.com/watch?v=rxPa9A-k2xY
sundvor 8y ago
Not that video, but at least it shows the automatic trim system in action - and is rather educational: https://youtu.be/l62NvkRWa5E https://youtu.be/l62NvkRWa5E . Even better: https://youtu.be/xixM_cwSLcQ https://youtu.be/xixM_cwSLcQ

Does anyone have a mirror of that video?

by lysp 8y ago

Does anyone have a mirror of that video?

This was posted on PPrune: "Originally Posted by infrequentflyer789 Since this video may not be coming back I'll post a sort of transcript from memory since I was lucky enough to get to watch it. I'll try and just describe what I saw and keep my commentary/speculation to a minimum - in <italic>. Bear in mind this is a non-pilot observer's take on it from flaky memory: There is a fair bit of intro talk then the sim. They are in NG sim, not MAX, no surprise there. Mentour in left seat. They start at low altitude, I think it was commented on, not at takeoff, I can't remember if they showed putting flaps up or started with flaps up and said it was just after flaps up. No stick shaker, that I saw. <presume means no elevator feel shift either, and that actual AOA error is not being simulated> IAS disagree then simulated - or they just did the memory items, I didn't notice warning light (not that I would) and he didn't note it, there was an aural alarm but I think that was for AP disconnect <I don't think this is exactly what the accident flights faced, they had shaker and IAS disagree from takeoff> IAS disagree memory items, AP/AT OFF, FDs OFF, 75% N1, 4degrees Throttles are pushed forward to get 75%, he comments that at low alt with denser air this is a lot of thrust and hence speed will increase Trim runs, obviously sim doesn't have MCAS so not sure if they are simulating runaway or if he is doing it with the column switches Comment is made that he was _expecting_ trim to run, because speed is changing, he says it will take a couple of cycles of fighting it with the switches before being definite that it is wrong They discuss (he raises) that he is having flight control issue, they conclude it is trim that is the problem, they now run the stab trim runaway memory items finishing by hitting the switches. At this point he is clearly holding quite a bit of pressure on the column, but not obviously losing control of pitch Now he points out that trim has only got down to (I think) 3 degrees on the indicator (zero being full nose down, I think) and that they are now going to "try something" - video captions say "don't try this at home", like we've all got a FFS in our shed or a 737 on the drive :-) At this point the guy in the right seat uses the handle to wind the trim further _forward_. He stops when he clearly cannot wind it further - but they point out that it's still not at full nose down Mentour is obviously struggling to keep the nose up at this point. I noticed he didn't seem to have the shoulder straps on (right seat did), possibly because he was frequently turning round to talk to the camera. That probably didn't help, but on the other hand he didn't have stick shaker or feel shift to cope with either. Now, with Mentour pulling back, the right seat guy tries to wind the trim back with the handle - and he struggles to move it at all They stop the sim, I think it was after stopping that he noted that at that point they were at 310 (maybe he said 340) knots. I think there was then some further commentary, at one point I think he mentioned the rollercoaster to unload the stab and allow trimming, but commented that close to the ground the instinct is to pull back - I may be imagining that or remembering it from another video though. And that was about it. I can try to answer questions on the video if anyone has any. The eye-opener for me wasn't the force on the control column (which was held anyway), it was that the trim couldn't be moved, in either direction. From somewhere I had got the impression that those wheels had a lot of leverage, due to the gearing, which was why a lot of turns would be required, but it seems that a lot of turns would be required and a gorilla to make them..."

CamperBob2 8y ago
Since this video may not be coming back I'll post a sort of transcript from memory since I was lucky enough to get to watch it. I'll try and just describe what I saw and keep my commentary/speculation to a minimum - in <italic>. Bear in mind this is a non-pilot observer's take on it from flaky memory Was the video pulled? Who did that, and why?
- mhandley 8y ago
  The speculation is that his employer, which flies a lot of 737s, didn't like him using a company simulator to illustrate a safety issue with the 737.
- colde 8y ago
  He pulled it himself. https://twitter.com/MenTourPilot/status/1113723580284583936 https://twitter.com/MenTourPilot/status/1113723580284583936
  - jillesvangurp 8y ago
    His channel is worth following. He often posts insightful stuff related to incidents with 737s or just general information. He had a nice video about emergency procedures with a total engine failure in (probably) the same simulator just a few weeks ago.
TheSpiceIsLife 8y ago
Is anybody here capable of calculating the force required to move the trim tabs on a 737MAX at 310 knots at low altitude? I imagine at that speed there would be quite some force on the elevator and trim tabs.
- mhandley 8y ago
  There's no trim tab on a 737 - the whole horizontal stabilizer is moved to trim the aircraft in pitch. Normally this is done electrically, but the stabilizer jackscrew can also be moved using manual trimwheels that move the jackscrew using physical cables. Whether this is possible at high airspeed while the stabilizer is trimmed nose down, and the elevator is being pulled up as hard as you can to avoid diving - that's the question that is being raised. Edit: this shows the jackscrew in operation: https://www.youtube.com/watch?v=rxPa9A-k2xY https://www.youtube.com/watch?v=rxPa9A-k2xY

sundvor 8y ago

Not that video, but at least it shows the automatic trim system in action - and is rather educational: https://youtu.be/l62NvkRWa5E https://youtu.be/l62NvkRWa5E . Even better: https://youtu.be/xixM_cwSLcQ https://youtu.be/xixM_cwSLcQ