Problems with speed modes during take off

[Guest alex_th2]

Captains!Im having trouble and wonder if you have some recommendations. I am taking off and my strategy is to fly the initial part of the take off manual only with auto thrust engaged. Then at app. 3000 FT, I switch to FL CH mode to reach the initial altitute. Thereafter I engage VNAV and LNAV to follow the FMC route. The issue is that while climbing on FL CH mode, the speed mode is not changing from TO2 to CLB. It will stay in TO2 mode even after I have engaged VNAV. As a consequence it is almost impossible to reach cruise altitute because the commanded SPD mode stays at TO2. Only when I press the THR button on the MCP, will the spead mode change to CLB. A look at the PS1.3 manual tells me that the THR switch is inoperative during FLCH, VNAV and TO/GA - but in PMDG its still possible to use it. So in short: Why is the speed mode not changing from TO to CLB mode when not in VNAV mode during take off? Thanks a lot!Cheers,Alex

[downscc 1,327]

My guess is because with MCP Speed mode it stays at your setting, which would be my preference. I engage VNAV earlier, at 1000 agl or lower to settle down into flap retraction acceleration. Seems to work smoothly.

[crvm 0]

Have to look at this more. Not sure...Best,Randy J. Smith<<>>

[cowpatz 243]

Alex pressing the thrust switch is the action required to get out of take off thrust mode if VNAV is not armed. The switch is operative after passing thru 400ft AGL. It will change the thrust to the armed CLB thrust setting.