New pilots on the 737. Watch that pitch up on go around
The other thing is, people don't understand the difference between trimming a moving stab and an elevator. If you are pushing full forward to save the day, you don't trim a flying stab to stick position. You'll end up going 'over the hill' so to speak. That stab on the 737 is very powerful and easy to over control.
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Early intervention to contain a pitch up is vital; especially in IMC or dark night condition
Yes, there was a profound pitch up moment but gee it wasn't that hard
Should that not say that pressing TOGA gives go-around flight guidance however it may or may not give go-around thrust. Eg EK 777 at DXB.
I can’t really comment on that, as I have no knowledge of the 777 having never flown it. However that was an attempt to go around initiated after touch down, which isn’t what the OP on this thread was talking about.
But ok, I’ll modify what I said. With speed mode selected pressing TOGA will, if it is working as designed, with the aircraft airborne, give you TOGA thrust. Totally nothing to do with the flight director commands which will happen whatever the A/T is doing.
Of course you should still be covering the thrust levers and do something yourself if they don’t move, same as any time a power change is supposed to happen with the A/T engaged.
But ok, I’ll modify what I said. With speed mode selected pressing TOGA will, if it is working as designed, with the aircraft airborne, give you TOGA thrust. Totally nothing to do with the flight director commands which will happen whatever the A/T is doing.
Of course you should still be covering the thrust levers and do something yourself if they don’t move, same as any time a power change is supposed to happen with the A/T engaged.
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And a couple of other things, highly relevent to this discussion:
1. How does the trim work? Please see this excellent article: https://skybrary.aero/bookshelf/books/2627.pdf
A little quote from that article, to whet your appetite:
2. Be careful in the application of nose-down trim. The FlyDubai 737-800 that dived into the ground following a go-round at Rostov-On-Don in 2016 was put into that attitude by an excessive application of nose-down trim (the application lasted for 12 seconds!). Having established the aircraft in the go-round, the PF (Captain) then pressed the trim switch forward, and held it there, knowing that several seconds of application would be required. His intention, no doubt, would have been to release the switch after a few seconds, but with the high cockpit workload at the time, it appears he then became distracted - with his thumb still pressing the switch forward!
The end result was a 12 second nose-down trim application that, after sending loose objects and unrestrained passengers onto the ceiling, gave a 50 degree angle of descent!
https://en.wikipedia.org/wiki/Flydubai_Flight_981
1. How does the trim work? Please see this excellent article: https://skybrary.aero/bookshelf/books/2627.pdf
A little quote from that article, to whet your appetite:
Your speed is low, about Vapp and the thing is pitching firmly upward. You need ample forward stick/elevator to restrain it. You don’t want to carry this load for long so you retrim. Question: if you run the trim forward while maintaining forward pressure on the wheel, what happens? Hands up all those who think the load reduces to zero. I see a lot of hands. My unscientific polling to date suggests that just about everyone is convinced that this is what happens, but it doesn’t.
The end result was a 12 second nose-down trim application that, after sending loose objects and unrestrained passengers onto the ceiling, gave a 50 degree angle of descent!
https://en.wikipedia.org/wiki/Flydubai_Flight_981
Your speed is low, about Vapp and the thing is pitching firmly upward. You need ample forward stick/elevator to restrain it. You don’t want to carry this load for long so you retrim. Question: if you run the trim forward while maintaining forward pressure on the wheel, what happens?
But that isn't what pilots do (or should'nt do). You're pushing to maintain an attitude (not pushing to maintain a force), and as soon as the trim starts taking effect, the stick-load will reduce because as you're maintaining the GA attitude; you'll be reducing the pushing on the stick. Basic IF technique.
I suspect Rostov was more of a fatigue issue than a system design issue. Talk to a pilot flying similar rosters and they will tell you that it’s hard enough steering your car in a lane when that tired let alone flying a missed approach in the early hours of the morning. The pilot in question had already resigned siting fatigueing rosters as the reason.
