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Disabling step climb guidance in the fmc?

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I'm flying a North Atlantic track and need to keep a certain altitude. How do I disable the step climb guidance bugging me in the fmc and on the nd? I read there is a crash if you change rvsm step climb, so what do you do? Thanks

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Just enter '0' in the Step Climb entry on PERF or VNAV CRZ. 

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Just enter '0' in the Step Climb entry on PERF or VNAV CRZ. 

 

Thank you! But doing this on the ground causes a ctd? At least I think I read that in the patch update section.

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Ignore it? That way you can step climb when you leave the NAT.

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^ yeah, the airplane saying you should step doesn't mean you have to. You're the pilot, not the FMC.

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I wasn't aware of that bug. I've changed from RVSM>0 on the ground and airborne without any problems many times! But yeah as they say - can just ignore it too.

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As Ryan said:

You're the pilot, not the FMC.

 

That said, you should tell the FMC what you, as the pilot, plan to do:

Entering 0 will help your fuel predictions by telling the system that you're remaining at a suboptimal flight level after where the step climb would be.

 

As far as I know, changing the STEP value only causes a CTD on the ground, currently.  It won't hurt anything if you wait until you're in the air to change the value, though your fuel predictions may be off until that time.

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I'm flying a North Atlantic track and need to keep a certain altitude. How do I disable the step climb guidance bugging me in the fmc and on the nd? I read there is a crash if you change rvsm step climb, so what do you do? Thanks

What you would normally do is:

- at the NAT entry point enter for example .84/360

- at the NAT exit point you enter for example E/380 (E=Econ speed and 380 should be a correct FL for the direction of flight and as close as possible to Optimum/recommended altitude).

I always first look at what the FMC would want without manually entering Step climbs....and then I put Step climbs in that are as close as possible to that what the FMC wanted and is in accordance with my NAT clearance as well. Sometimes it is better to stay in FL360 all the way to KJFK (normally you use Step Size =0 for this but you can achieve the same by entering /FL360 untill short before top of descend) and other times a climb to FL400 is better. Depends on weight/wind/turbulence forcasts etc)

 

Even with a step size of 1000ft (RVSM) or 2000ft on the Vnav Crz page (so not 0) the FMC will assume FL360 until the exit point.

FMC step climbs will not be auto calculated across the NAT track if you do it like this.

 

 

I dont think this causes any CTDs.

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Ah, sorry, yes.

 

As allways you do have to enter that S as well.

So .84/360S and E/380S for my examples above.

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^ yeah, the airplane saying you should step doesn't mean you have to. You're the pilot, not the FMC.

 

I know that, I just have little things that bug me, like looking at the nd or fmc for a few hours while it bugs me about step climbing. I just wanted a way to disable it. Thanks everyone for the useful info.

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