January 7, 200719 yr I need some guidance in understanding the ACT ECON CRZ page in the FMC.In my current flight, the planned altitude is 330In the ALT ECON CRZ page it states:CRZ ALTFL 330STEP TOFL370STEP SIZEICAOOPTFL301MAXFL344Why does it say STEP TO FL370, when MAX is 344? Is that the maximum altitude it should reach after a sufficient burn, if so, how can I program it to automatically creep up to that altitude as the plane lightens?
January 8, 200719 yr Hi there. The "STEP TO" part is telling you the next level you are planning to step up to. If your ALT is FL330, and your step-climb size is ICAO (4000ft), your next step up will be FL370. (On the occasions I have travelld on long hauls with BA/QF, they tend to use a 2000ft step climb as opposed to the ICAO/4000ft. I think it saves a bit of fuel, as you are always closer to your OPT alt).Anyway, right below the "STEP TO" line is another line saying something like "AT 0504Z/1134NM" for example. That line will count down and down until it is time to step up to FL370 (if you are at FL330, this is when your OPT ALT is FL350), in which case it will say "NOW". The STEP TO line is not telling you when to step (that's the line below), it's just telling you the next planned step. Towards the end of your flight after making your final step, you may notice the "when" line will say NONE. This means it isn't economical in the time you have remaining to make another step to the altitude "planned" above (in your case, your ALT + 4000ft).Hope this helps!
January 8, 200719 yr Yeah, thanks that helps a lot. So the system doesn't automatically increase the flight level, it just informs you when is it most economical to increase it?
January 8, 200719 yr >Yeah, thanks that helps a lot. So the system doesn't>automatically increase the flight level, it just informs you>when is it most economical to increase it?>Correct it doesnt automatically step to, just lets you know when it is economical to. Then you have to set the MCP to step up.And you can change the step size of your choice (in 1000ft increments) rather than have to wait for the standard ICAO 4000ft step.Jay Jay Vorkapic
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