XRAYretired wrote:AABusDrvr wrote:XRAYretired wrote:Well, not quite. Airspeed Unrelaible QRH 10.2 points you to the performance tables. The applicable table for climb is Flaps UP, Max climb thrust.
http://www.737ng.co.uk/737-800%20Quick% ... QRH%29.pdfWe have 4 crews who all apparently all did this when encountering similar circumstances.
One poster tried to close down this thread when this information was first posted although, probably just a coincidence.
Ray
The climb table you referenced above is for a 280KT/.76 M climb. Thats not the chart you would be using, if you were in the terminal area, intending to return and land. The "Terminal Area" table at the bottom of that page would be the correct table.
An informal poll of every first officer I've flown with recently has had 100% "unreliable airspeed" as the answer, when asked, "If you got a stick shaker right after rotation, what QRH procedure would you start with".
OK. Thanks for the info.
Can you speculate as to why 4 crews appeared to follow the former with 3 subsequently intending to return?
Ta.
Ray
Let me start by saying I don't lay blame on the crews in either of these incidents. I've flown both A and B airplanes, not a "fan boy" for either, it just happens I currently fly the 737. IMHO, Boeing (and the FAA) dropped the ball bad with the design, and implementation of the MCAS. I do however, scratch my head at some of the actions of both crews. The full CVR transcripts would help understand things tremendously.
I won't even speculate on an answer to why the crews acted as they did, other than their training and experience led them to believe the actions they took, were correct at the time.
I'd like to know why the Lion Air captain was able to maintain control of the airplane for several minutes, and many MCAS trim command cycles, but when he passed control to the first officer, he wasn't able to keep the airplane flying.
Or why the ET crew couldn't, or didn't get the airplane back in trim with the normal stab trim. The Lion air captain at least, was seemingly able to do this several times.
I will never understand why the ET crew tried to engage the autopilot three times with an active stick shaker. Or why they never got the power back from the takeoff thrust setting. Pitch+Power=Performance is as true in a 737, as it is in a Cub.
There isn't any real procedural guidance about retracting the flaps, but I don't believe in a similar situation I would. Two reasons here, first is I know with flaps 1 or 5, I have more maneuver margin than if the wing is clean. Second would be that if I had a continuous, false stick shaker right after takeoff, I'm going to go right back and land. No reason to clean up, and accelerate, as long as I can assure terrain clearance, and it would appear the ET crew did climb high enough to do that.
I don't understand why any of these crews didn't do the "RUNAWAY STABILIZER" NNC, when the stab trim kept doing something other than what they told it to do. Maybe the check list needs to be renamed "UNCOMMANDED STABILIZER MOTION" or something like that.
When everything is working properly, the MAX is a great airplane to fly. I do hope they get this mess sorted out, and the airplanes resume flying before long.