B757 takeoff and approach profiles
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B757 takeoff and approach profiles
Ladies and Gentlemen,
B757 pilots, please put me out of my misery… I fly the B737, and i’m looking at the operating procedures on other aircraft out of interest, and I have some questions about the B757. Don’t ask, I just want to know!
For an EFATO, at acceleration height, why do you use VS 0-200fpm? Why can’t you just increase the speed on the MCP to the flaps up maneovering speed? If its an issue with the TO mode, couldn’t you use FLCH?
On an normal low drag ILS which we often fly in the UK, what flap/speed profile do you use, e.g. before and after glideslope capture? Do you ever use Flap 15 and flap 20 on the glideslope with the gear up?
For a single engine ILS, what flap/speed profile do you use?
Thank you, I really appreciate your feedback!
B757 pilots, please put me out of my misery… I fly the B737, and i’m looking at the operating procedures on other aircraft out of interest, and I have some questions about the B757. Don’t ask, I just want to know!
For an EFATO, at acceleration height, why do you use VS 0-200fpm? Why can’t you just increase the speed on the MCP to the flaps up maneovering speed? If its an issue with the TO mode, couldn’t you use FLCH?
On an normal low drag ILS which we often fly in the UK, what flap/speed profile do you use, e.g. before and after glideslope capture? Do you ever use Flap 15 and flap 20 on the glideslope with the gear up?
For a single engine ILS, what flap/speed profile do you use?
Thank you, I really appreciate your feedback!
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For an EFATO, at acceleration height, why do you use VS 0-200fpm?
Apologies; it's been a loooong time ago I was B757-ing. Is this a Boeing SOP or a company SOP? It does sound odd, but then again I came across a couple of B767 operators who didn't like/understand VNAV and other (in those days) 'dark-arts' modes and used V/S instead; at some the strangest moments.
Apologies; it's been a loooong time ago I was B757-ing. Is this a Boeing SOP or a company SOP? It does sound odd, but then again I came across a couple of B767 operators who didn't like/understand VNAV and other (in those days) 'dark-arts' modes and used V/S instead; at some the strangest moments.
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VS 0-200fpm is a Boeing procedure, most company use it, my company uses VS 200, some do VS 0. The 3. segment allows a level off. Airbus SOP do the same, push to level off (VS 0) to accelerate.
I think using VS is the easiest way to do this. What would be the advantage using a SPD mode? Doesn't it still climb that way?
And yes we do use Flap 15 on G/S with gear up, sometimes even Flap 20.
I think using VS is the easiest way to do this. What would be the advantage using a SPD mode? Doesn't it still climb that way?
And yes we do use Flap 15 on G/S with gear up, sometimes even Flap 20.
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EAM, what speed down the ILS at typical landing weights does flap 15 give?
On the 737 NG, at the accel height we just increase the speed on the MCP to the Up/min-clean speed, so it accelerates in TOGA. I'm just wondering why it isn't done like that on the 757/767, for example if the TOGA or FLCH logic is a bit different? TOGA does accelerate and gives 0-200fpm anyway...
Thanks!
On the 737 NG, at the accel height we just increase the speed on the MCP to the Up/min-clean speed, so it accelerates in TOGA. I'm just wondering why it isn't done like that on the 757/767, for example if the TOGA or FLCH logic is a bit different? TOGA does accelerate and gives 0-200fpm anyway...
Thanks!
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On the 737 NG, at the accel height we just increase the speed on the MCP to the Up/min-clean speed
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0-200 fpm was single engine procedure..?
Been 2 years since I flew the 757 but seem to think we did FLC on a normal take off, or was it VNAV, or both.
No sure of anything anymore: I will do whatever the guy or girl signing the paycheck wants me to do.
19 jobs and 50 types, truly confused.
No more flying, quietly running my charter boat in Florida taking little old ladies on sight seeing cruises and writing my own procedures:
Been 2 years since I flew the 757 but seem to think we did FLC on a normal take off, or was it VNAV, or both.
No sure of anything anymore: I will do whatever the guy or girl signing the paycheck wants me to do.
19 jobs and 50 types, truly confused.
No more flying, quietly running my charter boat in Florida taking little old ladies on sight seeing cruises and writing my own procedures:
Because it's a Boeing procedure, in my Part B and in the FCTM.
Less flippantly, Boeing are targeting a level acceleration, so a mode that aims at level or near level flight works well. Modes that work are ALT HOLD or VS. I think at JMC it was ALT HOLD, ALT HOLD to fly a level accel. Now it's VS 0-200 which works well. Once at Ref80 FLCH will give a speed mode which will climb at Ref80.
FLCH for the accel will drive towards the selected speed but with no direct control over the gradient.
EAM has answered the approach flap thing.
Hope this helps.
Less flippantly, Boeing are targeting a level acceleration, so a mode that aims at level or near level flight works well. Modes that work are ALT HOLD or VS. I think at JMC it was ALT HOLD, ALT HOLD to fly a level accel. Now it's VS 0-200 which works well. Once at Ref80 FLCH will give a speed mode which will climb at Ref80.
FLCH for the accel will drive towards the selected speed but with no direct control over the gradient.
EAM has answered the approach flap thing.
Hope this helps.
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Caveat - no 757 background so my comments are generic.
The basic philosophy is a level third segment to accommodate reconfiguration to the final climb.
However, some aircraft accelerate sufficiently OEI to provide a problem with the flap retraction sequence. A modest climb can be used to slow the mismatch down just a little so that the target clean speed and configuration are more easily achieved as required. Provided the profile is as per the AFM, then the takeoff sums are all kosher.
As I recall, the 733/734 had a similar third segment arrangement ?
The basic philosophy is a level third segment to accommodate reconfiguration to the final climb.
However, some aircraft accelerate sufficiently OEI to provide a problem with the flap retraction sequence. A modest climb can be used to slow the mismatch down just a little so that the target clean speed and configuration are more easily achieved as required. Provided the profile is as per the AFM, then the takeoff sums are all kosher.
As I recall, the 733/734 had a similar third segment arrangement ?
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Gatbusdriver: Thanks, thats interesting (to me at least). I used to fly into LGW in the NG, if they ask for 160kts, we have to configure Gear Down Flap 15, unless we are very light, not very low drag. I recall, STN have 165kts until 4DME which works better for the NG, it means that we can stay gear up and Flap 5.
Denti: We don't arm VNAV on the ground or use it in SE operations on departure.
Towerdog: Yes I had a colleague a few years ago that got fed up with flying, and now does something similar to you down in Croatia! Enjoy!
Deltahotel: Thank you. I sit in the back of the sim and watch crews pretty much do the same profile every day, and seeing the same thing repeatedly, you start to ask yourself why we actually do something...
John_tullamarine: So you are saying that some aircraft accelerate so well that a rate of climb helps reduce the acceleration rate? The 737NG certainly doesn't (unless light), but it ain't bad..
Denti: We don't arm VNAV on the ground or use it in SE operations on departure.
Towerdog: Yes I had a colleague a few years ago that got fed up with flying, and now does something similar to you down in Croatia! Enjoy!
Deltahotel: Thank you. I sit in the back of the sim and watch crews pretty much do the same profile every day, and seeing the same thing repeatedly, you start to ask yourself why we actually do something...
John_tullamarine: So you are saying that some aircraft accelerate so well that a rate of climb helps reduce the acceleration rate? The 737NG certainly doesn't (unless light), but it ain't bad..
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some aircraft accelerate so well that a rate of climb helps reduce the acceleration rate
More a case of how long the flap retraction sequencing takes and the speed delta for the clean up. On some aircraft, it takes forever and a day .. on others, it all happens fairly smartly.
AFM guidance will match it all up for the crew.
More a case of how long the flap retraction sequencing takes and the speed delta for the clean up. On some aircraft, it takes forever and a day .. on others, it all happens fairly smartly.
AFM guidance will match it all up for the crew.
Empty with E4 engines and no derate, 25° pitch up and still accelerating. Now image it trying to level off before flap retraction alt and it's easy to see why low alt cap is one of the biggest threats.
