I am on my way from EDDG to LFPB but after takeoff i can not select VNAV mode, when I took of I saw that i did not calculate V speeds but I have a whole VNAV path in my legs page but if if press the VNAV button it stays blank. Did i forgot something? PERF page is filled normally also cruise altititude is set FMC. EDIT: I am now flying at FL330 and see a t/d in my profile and on progress page FL in FMC is FL330 but still can not select VNAV

cost index is also filled in?

Yes cost index 30

A/T armed?

did you make sure that you also pushed the EXEC button after filling all the pages?

I am on my way from EDDG to LFPB but after takeoff i can not select VNAV mode, when I took of I saw that i did not calculate V speeds but I have a whole VNAV path in my legs page but if if press the VNAV button it stays blank. Did i forgot something? PERF page is filled normally also cruise altititude is set FMC. EDIT: I am now flying at FL330 and see a t/d in my profile and on progress page FL in FMC is FL330 but still can not select VNAV

Would need to see a pic !!

EDIT: I reentered cost index and problem is now solved. But cost index was filled in at 30 already and i could not engage VNAV, when I re entered it / overwrite VNAV worked again weird?

Did you re-execute after input of perf and take off data? I had same problem but just omitted to do the same. Also LNAV and VNAV (i think) should be initiated on the ground. Note to self - must read full thread!!!!!

Did you re-execute after input of perf and take off data? I had same problem but just omitted to do the same. Also LNAV and VNAV (i think) should be initiated on the ground. Note to self - must read full thread!!!!!

I did execute otherwise I would not have a VNAV profile in my LEGS page ;) and LNAV VNAV should be able to activate in air, when on interception course.