July 8, 200817 yr I am wondering why when taking off if I engage VNAV or LNAV prior to the yellow line that follows altitude tape on the ND the aircraft wont go above 250 knots which when heavy wont allow me to raise the flaps all the way. If I wait and engage after the line disappears the aircraft will fly at a higher speed. (272kts on my current flight) By the way I do understand that speed above 250 knots is prohibited below 10,000 feet.Thanks Andrew
July 8, 200817 yr Commercial Member Speed above 250 knots is not prohibited below 10000ft you fly your min clean speed or VREF + 10.Rob Rob Prest
July 9, 200817 yr Andrew:The FMC defaults to the US FAR mandated 250kts to 10000' restriction. In Europe and other places, there is a different mindest- allowing for earlier acceleration. As Rob said, feel free to ask for a speed waiver if needed (at higher TOWs). Deleting the FMC restriction can be done from the VNAV CLB page.BA SOPs call for noise abatement climbs of Flaps 10 + 10 to 4000' so that is what I typically fly, through SPD INTV. Once past that I habitually increase based on flap retraction schedules while asking for a speed vaiver. Sometimes I get it, sometimes (particularly in the Colonies ;) ) I don't.You will note the FMC automatically commands a higher speed once through the FL100 barrier (should you not have manually DEL the restriction).Remember Bill (Bulfer's) caution that SPD INTV is there for a reason- use it as and when necessary- it sure makes on schedule flap retractions a breeze!Best-Carl F. Avari-Cooper BAW0225http://online.vatsimindicators.net/980091/523.png| XP Pro SP3 | 2 x APC UPS | Coolermaster Stacker 830 SE | Gigabyte P35 DS3R | e8500 @ 4gHz | Tuniq Tower 120 | EVGA 8800GT 512MB | Creative X-Fi Fatal1ty | 2 x 1 GB Corsair XMS2 | 2 x 320GB WD Caviar RAID 0 | Corsair HX620W PS | CH Products Yoke-Pedals-Throttle Quadrant | Aerosoft 747MCP-EFIS-EICAS | Best- Carl Avari-Cooper
July 9, 200817 yr Author Thanks Carl. Very good information. I appreciate you taking the time to help me. Andrew
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