Static port size

[AdrianParticipant]

So what happens if your static hole port is larger than the calculated size. I made mine larger than the calculated value to allow access to the arming switch…. so I’m trying to understand what happens if its too big. I guess along the same lines how about the vent holes for the other compartments. I’ve seen several recommendations as to the values and since Im potentially flying Mach 2+ I wanted the holes a little larger to accomodate the rapid change in pressures, vs slower flights. Thoughts??

I think it mostly just means that your av-bay will equalize faster with the surrounding atmosphere (good), but maybe allow more dramatic pressure swings during transonic transitions (not a problem if you’re using a Mach-immune altimeter or a correctly-set Mach inhibit delay). Wilke’s shot to 25k last year had barely any transonic effect show up in the recorded data, and I suspect it was because he was using a relatively small vent hole a good distance from the nose. In my supersonic flights last year, with about a 1/8″ hole right near the shoulder for altimeter arming, the recorded altitude had major transonic effects, even going negative at one point for one of the flights. But the altimeter was set up to ignore the baro data for high speeds, so it wasn’t an issue.

What do you have planned to go > Mach 2? Sounds like fun. I have some high-performance flights planned, myself.

[Author]

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