When I performed a 600 miles flight from Oslo to Troms

Hi Andreas,mine is just a guess, but maybe the winds changed and you ended up with a tailwind, in which case IAS would decrease if you previously had headwinds and VNAV leveled to compensate until it got up to the FMC speed to resume climb.Regards,Bjorn

unfortunately not. The wind was still a head wind. After two minutes still the same problem. The only solution is to climb further with V/S engaged. Just reproduced the problem on another flight.

Andreas,Really silly question : the baro was reset to 29.92 or 1013 yeah ?Regards,Vangelis=========================================== E. M. Vaos Precision Manuals Development Group www.precisionmanuals.com===========================================

Thanks for your reply! Sure, it was on standard 29.92. It is even more difficult not to remember setting it on standard because the INH setting flashes yellow when passing trans alt.

Hi!I have to say that I've just experienced the same problem. Did a shot flight from LOWW to LOWL, VNAV got disconnected somewhere half-flight and I haven't been able to switch it on again...There was also a message on the FMC saying "VNAV disconnected"...Any ideas? Am I doing something wrong?Otherwise a fantastic bird!!!regards,Joerg

Sorry, J