The E6B is a very handy tool, particularly for aircraft I've never flown or don't fly often, when wanting to adjust power settings for cruise, etc. However when doing some testing as part of a discussion I've noticed that there's actually a pretty significant flaw:
The E6B doesn't adjust for altitude.
Case in point,
Per E6B, the F4U lists the following power settings:
WEP: 2700/57.5"
MIL: 2700/54"
Normal: 2550/44"
Cruise: 2150/36.5"
Now, cruise settings at some altitudes I was already familiar with not being possible (at 25k maintaining cruise with the settings above can't be done. Your throttle is maxed and you STILL can't match the indicated MAP at 2150RPM). While this is probably old new to some, I'd never paid attention to the fact that this also applies to the other settings as well:
At ~12,000ft and 17,000ft, the F4U actually reaches 59" MAP under WEP, while at various altitudes in between MIL falls somewhat below 54" MAP.
Would it be possible to see the E6B power setting data either adjust depending on your altitude, (say, in 5000ft or whatever blocks) or see the chart expanded out to include settings at different altitudes?
It's less of an issue for people who have a particular ride they fly often enough to feel the difference, but could be useful when you strap into a new bird or one you don't fly often.