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ghiom

Proper T/O procedure with AP?

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HelloCan some real pilot (or pretend to be) described to me?I am looking for a procedure when flying with AP from 500ft AGL, with a SID.I usually preferred to engage the AP at 500ft AGL with the VNAV and LNAV preselected. I would expect the AP to maintain V2+15 at TO thrust climb until flaps retraction altitude (1000ft-2000ft as pre-selected in the FMS) and then automatically select 250 IAS until 10,000ft, allowing acceleration with scheduled flap retraction.As per various sites, it does not seem to be the proper way.With this method, the plane climbs like a rocket at 4000ft/min at lower than expected speeds even if TO-60 CLB-2 are selected.can someone please advise.Ghiom

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I'm a private pilot, does that count? heh. Yeah, anyway, um I would say to you that during a standard thrust reduction takeoff, try not switching on VNAV until you've reached your thrust reduction altitude. At takeoff, set V2 +10-20 in your MCP, this will force the flight director to give you the vertical guidance required to maintain that speed. Climb at V2 + 10-20 until either 1000ft agl or 1500ft agl. At that point you should engage VNAV. Also there are other options available to you, you can use your lvl change mode while climbing to 10,000 at 250 knots. Yeah, you'll climb fast, 4000ft/min isn't as fast as you think, and remember altitude is your friend on takeoff, the point is to gain as much as you can incase of engine failure of course. Weight and temperature will ultimately decide how fast your plane climbs, props or jets, also look at a real life 757, I think you'll immediately notice how large her two engines are compared to how sleek and thin she looks, that's usually a good indication of power. Back to the climb thing, just an example, I've seen our jet (an E-3) climb at 4000+ft/min when we were light, which is amazing to see considering fully loaded we climb like a rock.Jeff

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Well Ghiom, I'm a flight engineer on a DC-10 (military) and actually compute the perfomance for the pilots. Most airliners are flown the similarly so I'll tell you what DC-10 procedures are. Normally you would rotate and retract your gear. Climb to pressure height for acceleration (1500ft AGL or obstacle clearance height)at V2+ 10. You would climb out at V2 in the case of engine failure. Upon reaching pressure height for acceleration you would retract the flaps at VFR and retract your slats at VSR. Select climb thrust at this point and and bug yourself up to 250 and start the second segment of the climb. It is then that the autopilot is switched on. I wouldn't turn on the autopilot until the airplane was at least above its pressure height for acceleration, and your wings are clean. As far as climb rates are concerned.....I see climb rates in excess of 4000fpm in our KC-10 on proficiency flights all the time. It's not uncommon when your jet is light. I am a furloughed mechanic for a major airline and was taxi and runup qualified on the 757. I'll tell you this much....this airplane is a rocket!! When I took this airplane out to the runway to do a high powered run-up, I had to have at least 42000 lbs of ballast fuel on the jet to run ONE engine up to takeoff power. I was required to have 65000 lbs of ballast fuel to run both engines to takeoff power!! This airplane was designed to get out of high temp/pressure altitude environments and I assure you it surely will! I would say that your climb rates are probably normal.-Dwayne

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Thank you for your reply.The problem that it is climbing so fast (although de-rated T/O) that all these events in sequence happen very quickly and you get easily lost.Thank you again.However, I would be pleased to know how the designers of the plane (PSS) actually do.Thank you PSS.Ghiom

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HI, I am flying the Falcon 2000EX and previously I flew the Dornier 328 both jet and turbo-prop.We usually take off with HDG modes selected and we select a pitch of about 15

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Hi,Real world T7,VNAV armed on all Takeoffs, LNAV depending on the lateral profile given by ATC.Autopilot can be engaged from 200ft AGL and done on numerous occasions.I think this is exactly as you descibe.Cheerio,Sjaako

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Hiya :-)I fly the 757 around Europe:Before pushback we have V2 dialled in the MCP speed window with the FDs off. Once V2 has been dialled in both FDs are selected on which arms TO for pitch and roll. No other mode is armed.For takeoff we spool up the engines to 1.2EPR and then once stabilised press EPR/N1 - the autothrottle gives commanded EPR. Once airbourne assuming everything is working, the FD will command a pitch that results in the greater of V2+15 or liftoff speed+15. We fly this speed to the acceleraton altitude normally 1500' AAL and then select CLB thrust and VNAV. Autopilot can be engaged at this point. A roll mode such as HDG SEL or LNAV for the SID, can be selected at 400' AAL.If an engine fails the commanded pitch is V2 or airspeed at liftoff whichever is greater. We fly at this speed to the single engine acceleration altitude, normally 1000' AAL unless terrain dictates otherwise, the call for the autopilot to be engaged. This opens the VS window and the PF then dials in 0-200 fpm to accelerate and clean up. At VRef30+80 FL CHG is used to continue the climb at max. continuous thrust.Hope this helps :-)Mike

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