Just noticed that if you choose an RNAV approach for landing that the MCP will allow you to dial a setting that's close to your minimum for landing. So if your MDA is 522 it will go from 600 to 530 to 500 as you dial down the MCP knob. Am I right on this? I saw it twice.

 

Eric W

This is proper function from what I understand.

When AUTO is selected on the altitude selector outer knob (with the other option being 1000), the behaviour as you explained will occur.

Just noticed that if you choose an RNAV approach for landing that the MCP will allow you to dial a setting that's close to your minimum for landing. So if your MDA is 522 it will go from 600 to 530 to 500 as you dial down the MCP knob. Am I right on this? I saw it twice.

 

Eric W

Yes this is normal/correct behavior. But it has nothing to do with the kind of approach you selected in the FMC! As soon as you have Baro minimums (EFIS panel, left knob) AND you have the Altitude selector in AUTO then as wind the altitude down through your previously set Baro Minimums, it will stay close to those Baro minimums. (rounded of to the next higher 10ft). So in case Baro minimums of 522ft are set then the altitude window in AUTO jumps from 1000 - 900 - 800 - 700 - 600 - 530ft

That's really cool