B 737 Autothrottle
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ManaAdaSystem,
Sorry about the '-something' in my earlier posting - but having got to the point of writing my posting, I couldn't go back and check your username, which you have to admit is perhaps not the most instantly memorable! My best regards to you, anyhow.
I'm not certain whether the question from Pprune Towers was directed at me, but the aircraft with the better design are basically Airbus, though the very best flight deck I have ever used was on the Fokker 70/100, which had a design and operating philosophy which leaves everything I've seen before and since standing. Moreover, the flying controls were still mechanical with hydraulic power.
Incidentally, it was in a F100 that my friends lived thanks to the Alpha-floor. Scenario was a fast, high, approach with the FO flying. Configuration was Flap 42, Gear down, Speedbrake fully out, Approach Idle thrust.
Feeling uncomfortable, the Captain instructed the FO to go-around, but the FO reverted to previous type and de-selected autothrottle (switch on end of thrust lever grip) instead of TOGA (trigger under thrust lever grip). He then wondered why the FD hadn't commanded a pitch up, so pitched up to approximately 20 degrees. Fortunately, the Alpha floor activated immediately and the Speedbrake re-stowed automatically, meaning that they recovered by about 200'AGL about a mile out from the runway. I am aware that this scenario has occurred more than once. In a 737 they might not have been so lucky.
Sorry about the '-something' in my earlier posting - but having got to the point of writing my posting, I couldn't go back and check your username, which you have to admit is perhaps not the most instantly memorable! My best regards to you, anyhow.
I'm not certain whether the question from Pprune Towers was directed at me, but the aircraft with the better design are basically Airbus, though the very best flight deck I have ever used was on the Fokker 70/100, which had a design and operating philosophy which leaves everything I've seen before and since standing. Moreover, the flying controls were still mechanical with hydraulic power.
Incidentally, it was in a F100 that my friends lived thanks to the Alpha-floor. Scenario was a fast, high, approach with the FO flying. Configuration was Flap 42, Gear down, Speedbrake fully out, Approach Idle thrust.
Feeling uncomfortable, the Captain instructed the FO to go-around, but the FO reverted to previous type and de-selected autothrottle (switch on end of thrust lever grip) instead of TOGA (trigger under thrust lever grip). He then wondered why the FD hadn't commanded a pitch up, so pitched up to approximately 20 degrees. Fortunately, the Alpha floor activated immediately and the Speedbrake re-stowed automatically, meaning that they recovered by about 200'AGL about a mile out from the runway. I am aware that this scenario has occurred more than once. In a 737 they might not have been so lucky.
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Question was rhetorical rather than directed at you portly. I genuinely agree with everything you wrote.
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Regards from the Towers
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Regards from the Towers
[email protected]
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Im not sure what all the kaffufle is about.
2and70 whenever I have a question the books cant appear to answer, I generaly answer myself by trying it out the next time I fly the aircraft. Your question: Can you fly a manual descent, with manual thrust, with no FD, with the A/T armed and the other FD showing pitch to maintain the MCP speed (ie Lvl Chg) or Alt Hold? I confirmed the rationale the books say, on descent into Ha Noi last night. I tried it. And YES, you can. QED.
About Portlys comments (I find them on the money but not "devestatingly accurate"!):
Doesnt it all come back to knowing your aircraft? Despite the 737s shortcomings (and I agree with you, there are many of them! See just a few Ive listed below), the Boeing philosophy is: if you take out the autos then its your aeroplane. (which is what I infered in the last line of my 1st post). This is exactly how it should be - take out the autos and they will not interfere. Who wants something cutting in when youve taken it out? Confusion would reign if they did, and such confusion could lead to an accident. There is inherently nothing dangerous with hand flying with FDs, AT etc all taken out, so long as you realise what you are doing and whats going on esp with regards to the auto-protect function of the AT.
And mate I hand fly sometimes on descent with the AT in ARM, and dont have problems with the ARM to MCP SPEED transition at ALT ACQ. Wheres the "destability" you speak of (unless your asleep)? I just anticipate thrust with pitch and keep a safe hand on the throttles as a backup.
I very often fly an entire sector raw data with no FMC or FD or AT from push-back to taxy-in with absolutely no problem. The only brief I give the FO is to double-crosscheck all MCP selections, make every standard callout AND call them clearly (not just a grunt or mumble), and be aware of loss of AT speed-protect.
And Portly I realise I wasnt there on the Fokker event you discribe so there might have been extenuating circumstances, but isnt it a universal policy that someones hand is kept on any SB lever whenever its deployed? Im kept fast and high in the 737 almost everyday and in high workload situations (often in severe wx) and yes I agree the SB lever can be easily forgotten. But if some buggers hand is there its nipped in the bud before theres any trouble.
By all means take advantage of the protections offered in your aircraft if you want them. Thats what they are there for. There are times certainly when its good airmanship to utilise them to the full. But dont let your standard sink to the point where you solely rely on them.
PS With regards to 737 shoddy design Ports, Ill certainley hand you that bloodey rudder, as well as AP, the inbuilt Go-Around logic (2 eng), lack of SB autorestow at min protect speed, APU, autobrake RTO logic, the lack of reliability of the AT ARM mode at ALT ACQ when hand flying (unpredictable because it sometimes just stays in ARM even through to ALT HOLD), the uselessness of the speedbrakes esp at speeds at 240 knots IAS or less, the lack of really important info in the books (QRH is a bloodey disgrace, and Vol 2 was written it seems with an absolute minimum need-to-know philosophy) to name just a few.
Back to bed.
2and70 whenever I have a question the books cant appear to answer, I generaly answer myself by trying it out the next time I fly the aircraft. Your question: Can you fly a manual descent, with manual thrust, with no FD, with the A/T armed and the other FD showing pitch to maintain the MCP speed (ie Lvl Chg) or Alt Hold? I confirmed the rationale the books say, on descent into Ha Noi last night. I tried it. And YES, you can. QED.
About Portlys comments (I find them on the money but not "devestatingly accurate"!):
Doesnt it all come back to knowing your aircraft? Despite the 737s shortcomings (and I agree with you, there are many of them! See just a few Ive listed below), the Boeing philosophy is: if you take out the autos then its your aeroplane. (which is what I infered in the last line of my 1st post). This is exactly how it should be - take out the autos and they will not interfere. Who wants something cutting in when youve taken it out? Confusion would reign if they did, and such confusion could lead to an accident. There is inherently nothing dangerous with hand flying with FDs, AT etc all taken out, so long as you realise what you are doing and whats going on esp with regards to the auto-protect function of the AT.
And mate I hand fly sometimes on descent with the AT in ARM, and dont have problems with the ARM to MCP SPEED transition at ALT ACQ. Wheres the "destability" you speak of (unless your asleep)? I just anticipate thrust with pitch and keep a safe hand on the throttles as a backup.
I very often fly an entire sector raw data with no FMC or FD or AT from push-back to taxy-in with absolutely no problem. The only brief I give the FO is to double-crosscheck all MCP selections, make every standard callout AND call them clearly (not just a grunt or mumble), and be aware of loss of AT speed-protect.
And Portly I realise I wasnt there on the Fokker event you discribe so there might have been extenuating circumstances, but isnt it a universal policy that someones hand is kept on any SB lever whenever its deployed? Im kept fast and high in the 737 almost everyday and in high workload situations (often in severe wx) and yes I agree the SB lever can be easily forgotten. But if some buggers hand is there its nipped in the bud before theres any trouble.
By all means take advantage of the protections offered in your aircraft if you want them. Thats what they are there for. There are times certainly when its good airmanship to utilise them to the full. But dont let your standard sink to the point where you solely rely on them.
PS With regards to 737 shoddy design Ports, Ill certainley hand you that bloodey rudder, as well as AP, the inbuilt Go-Around logic (2 eng), lack of SB autorestow at min protect speed, APU, autobrake RTO logic, the lack of reliability of the AT ARM mode at ALT ACQ when hand flying (unpredictable because it sometimes just stays in ARM even through to ALT HOLD), the uselessness of the speedbrakes esp at speeds at 240 knots IAS or less, the lack of really important info in the books (QRH is a bloodey disgrace, and Vol 2 was written it seems with an absolute minimum need-to-know philosophy) to name just a few.
Back to bed.
