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jimimac

vnav speed in the 737/600

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hi when i have set up the fmc for my flight and have included a star for approach i have noticed that in the legs page the initial descent speed is at .81 then down to 10000 its 240 and this speed remains all the way down to about 1,500 this does not give a lot of time for the 737 to slow down,i have looked at the init ref page and with flaps 30 the speed should be about 130 depending on aircraft weight. so as the speed is too fast i either miss the altitude or am too fast to land. so at what distance from the runway should i be configured for landind with speed and flaps set. i thought if you used vnav this would take you all the way down to the runway. thanks, jim

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hi when i have set up the fmc for my flight and have included a star for approach i have noticed that in the legs page the initial descent speed is at .81 then down to 10000 its 240 and this speed remains all the way down to about 1,500 this does not give a lot of time for the 737 to slow down,i have looked at the init ref page and with flaps 30 the speed should be about 130 depending on aircraft weight. so as the speed is too fast i either miss the altitude or am too fast to land. so at what distance from the runway should i be configured for landind with speed and flaps set. i thought if you used vnav this would take you all the way down to the runway. thanks, jim
Hi jim,You have two options:1.- Open the LEGS page and in the right hand side program a defined speed for every waypoint.2.- Use the SPEED INT button in the MCP, that will open the speed window and will make possible to selec any desired speed while remaining in VNAV.180-190 kts and flaps 5 at the IAF is a good way to start the final phase of your flight.

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Boeing aircraft don't automatically slow for approach like the MD-11 or Airbus do... You have to either tell it to do it on the LEGS page or do it manually on the MCP.

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hi when i have set up the fmc for my flight and have included a star for approach i have noticed that in the legs page the initial descent speed is at .81 then down to 10000 its 240 and this speed remains all the way down to about 1,500 this does not give a lot of time for the 737 to slow down,i have looked at the init ref page and with flaps 30 the speed should be about 130 depending on aircraft weight. so as the speed is too fast i either miss the altitude or am too fast to land. so at what distance from the runway should i be configured for landind with speed and flaps set. i thought if you used vnav this would take you all the way down to the runway.thanks, jim
Hi Jim,I suppose you have not only looked at the Vref but selected one by actually selecting a flap setting in INIT REF (for example flap 30). Then you need to have enough waypoints between TOD and FAF or final marker so that the system can assign lower speeds to each successive waypoint. In the last resort, you can always switch to SPEED and manually adjust speeds for the flap extension sequence required.Hope this helps,BrunoPS (edit) oops, eveyone answered at the same time !

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thanks for the advice, i will try all of those suggestions, i like the vnav works but it was frustrating doing aflight only to bust the speed and alt. thanks, jim

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