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Marc_H

744 - Climb Speed?

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Hello Captains,today I flew from EDDF, Runway 18 via MARUN1S SID to KLAX.The VREF30 was 180kt, TOW 385,528KGOK, the 744 accelerated only to a speed of 264kt, not 300kt for weights above 309,000KG (VREF30+100 = 280+20kt).Please refer to Boeing FCTM: Page 1.4, 1.5 for the Flaps Schedule and Page 4.2 for "Climb Speed Determination".Servus!Marc

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Does the FCTM say why an extra 20kts is added to Vref plus 100?Sorry, I don't understand your equation "Vref30+100 = 280+20kts".VNAV engaged? Gear up/Flaps up?Cheers.Q>

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Hey am I glad you guys had the same response I did... I just didn't feel experienced enough in the 747 to comment. His climbout speed looked exactly right for below transition altitude to me.... mmmm.

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"His climbout speed looked exactly right for below transition altitude to me.... mmmm."Not sure what you mean Dan... If his actual speed was above the default 250/10000, then he must have cancelled his transition speed limit.Either way, he's not getting the correct speed (250kts or Vref30 plus 100)... unless there is something in the SID which is restricting his speed.Screenshot and FMC details required ;)Cheers.Q>

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I use V2+100, not Vref30+100, as my climb speed to 10,000'. Maybe I have been doing it wrong all along, but I have never had the above issue.

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"I use V2+100, not Vref30+100, as my climb speed to 10,000'. Maybe I have been doing it wrong all along, but I have never had the above issue."On the 747-400, V2 and Vref30 are very similar, but normally the values are based on Vref30.Cheers.Q>

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From a Boeing OM:"When flaps are up, pitch commands an acceleration to VNAV climbspeed. VNAV climb speed is the greater of:

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