Autothrottles departure to a low altitude operation.

[bluehawaii]

Ladies and Gents, I have a low altitude autothrottles SID operation question for an airport initial departure procedure. You are executing a takeoff with autothrottles to a low altitude (1500ft ) on an initial SID departure. What is the correct and proper way to manage the autothrolles and speed, so that the pilot does not climb through the published initial 1500ft altitude on the SID and also does not exceed a published speed limit, if assigned. (i.e. speed 165 kts)
[ Example - KTEB (TETERBORO, NJ, USA) "RUDY 6 RNAV DEPARTURE RWY 24 ([b]RUUDY6.RUUDY) WITH AN ASSIGNED SPEED INCLUDED" ]

[Intruder]

VNAV. Monitor closely to ensure it does what you expect it to do.

[eckhard]

Positive climb - gear up
400ft - check Lateral mode is LNAV or HDG as desired
As soon as possible, consistent with performance regulations - select Vertical mode to VS 500fpm and Auto throttle mode to SPD 165kts
1500ft - Check Vertical mode is ALT Capture and Auto throttle is speed mode 165kts as expected.

[Denti]

On the Boeing as Intruder said, VNAV should take care of it. On the Bus, autothrust engages with thrust reduction, usually 1000ft in the airlines i have flown for and the speed limit is taken from the database so will stay at 165. Therefore AT will keep that speed.

[bluehawaii]

Thanks Intruder, Eckhard and Denti for sharing your professional flight guidiance system procedure and knowledge.

[Monty Niveau]

Given the powerful thrust/pitch couple on many types, and the restriction on, eg, 737, on autopilot engagement (not below 1,000 ft), my preference is to use A/T to set thrust on the takeoff roll, and at 400 ft, LNAV, A/T disconnect, select about 70% N1 (depending on weight) and fly the aircraft to 1,500 ft like a PA28. ALT ACQ will take care of the level-off so far as the flight director guidance is concerned, and you’ll be left in MCP SPD / ALT HLD / LNAV / FD, from which autopilot engagement is comfortable for man and machine. I’m fortunate not to fly for operators who restrict manual and raw data flight and I can see that this would be a struggle for pilots whose skills have atrophied.

Another option, which I exercise when possible, is simply to ask ATC for a higher altitude. Often, this will be approved, and the threat has been mitigated.

[rudestuff]

757: fly the thing, follow the flight directors, wait for the ALT CAP. Then CLB, Ref+80, SPD, flaps on schedule.

You can stop at a lower speed/flap but setting a higher than current speed before you press SPD ensures the autothrottles don't roll back while you're still leveling off.

[Denti]

Given the powerful thrust/pitch couple on many types, and the restriction on, eg, 737, on autopilot engagement (not below 1,000 ft), my preference is to use A/T to set thrust on the takeoff roll, and at 400 ft, LNAV, A/T disconnect, select about 70% N1 (depending on weight) and fly the aircraft to 1,500 ft like a PA28. ALT ACQ will take care of the level-off so far as the flight director guidance is concerned, and you’ll be left in MCP SPD / ALT HLD / LNAV / FD, from which autopilot engagement is comfortable for man and machine. I’m fortunate not to fly for operators who restrict manual and raw data flight and I can see that this would be a struggle for pilots whose skills have atrophied.

Another option, which I exercise when possible, is simply to ask ATC for a higher altitude. Often, this will be approved, and the threat has been mitigated.

Ist that a new one? When i was flying the 737 it was 400ft for the Autopilot after departure. 100ft now for the Bus, but i am rarely that lazy.

https://cimg5.ibsrv.net/gimg/pprune.org-vbulletin/991x681/737ng_fcom_4204a703da7479e55d7197c56cb81db31679a24a.jpg
FCOM limitations excerpt

[Monty Niveau]

Denti, not all 737s are NGs. 1,000 ft is the minimum on the EG (and some operators with both standardise at it too). (I’m glad to fly the older ones, even though they misbehave, and we have the added bonus that we’ll shortly be able to generate a bit of extra revenue on the tails which are idle for the weekend, by putting one of them onto the air show circuit!).

[Denti]

Ah, ok, originally we used the 1000ft on the -300 as well, changed it later to 400 ft shortly before we phased in our first NGs. I guess it depends on equipment standard. Boeing is probably the only company with a longer option list than Porsche.

And yes, sorry to forget about the classic, it is so rare nowadays in europe, well, at least during daylight hours, that it is kinda easy to forget.