Where to Put the Static Port?

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Toobuilder

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Jan 19, 2010
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4,599
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Mojave, Ca
Just spitballing here but I'll bet you could machine a pitot with all three ports pretty easily. There's no real magic to the construction of an AOA pitot - I think a homebrewed version was covered in Kitplanes (or VAF) some time ago. But then heat becomes an issue. How about an Aeronca style static port "strapped on" to the Dynon piece? Wouldn't have to look bad.
 

Marc Zeitlin

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Dec 11, 2015
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609
Location
Tehachapi, CA
If I have too much trouble making the Dynon pitot-alpha probe and aft mounted static ports work, my fall back plan is the PIper blade pItot-static on one wing and Alpha probe on the other wing.
Your plane is not dissimilar in shape/issues from the 2-seat Lancair family of aircraft. I have no direct knowledge that their static systems work particularly well, but you may want to take a look at how they arrange their systems and do something similar. There are bunches out there, and they seem to do OK.

<RANT ON>I am at a total loss as to why NONE of the EFIS MFG's (Garmin, GRT, Dynon, at least for the ones I've checked with) allow you to modify a lookup table so that your IAS and CAS can be identical. Nor is there a modifiable lookup table for static pressure corrections, so that your altitude can be dead nuts on at all altitudes, attitudes, and IAS's. Geez - it's just freaking software, and pretty simple software, at that. The excuse that GRT gave for not allowing you to match IAS/CAS from GPS calibration runs giving TAS (you'll love this) is that they wanted to make sure that whatever the EFIS displayed matched the steam gauges that you might be using as backup. I **** you not. That logic would lead to requiring oats as an alternate fuel for you car, just in case it crapped out and you needed to feed your horse.</RANT OFF>
 

Dan Thomas

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Sep 17, 2008
Messages
5,077
<RANT ON>I am at a total loss as to why NONE of the EFIS MFG's (Garmin, GRT, Dynon, at least for the ones I've checked with) allow you to modify a lookup table so that your IAS and CAS can be identical. Nor is there a modifiable lookup table for static pressure corrections, so that your altitude can be dead nuts on at all altitudes, attitudes, and IAS's. Geez - it's just freaking software, and pretty simple software, at that. The excuse that GRT gave for not allowing you to match IAS/CAS from GPS calibration runs giving TAS (you'll love this) is that they wanted to make sure that whatever the EFIS displayed matched the steam gauges that you might be using as backup. I **** you not. That logic would lead to requiring oats as an alternate fuel for you car, just in case it crapped out and you needed to feed your horse.</RANT OFF>
Strange, isn't it? But they can give you the upper winds based on heading versus track, GPS groundspeed versus true airspeed, and temperature. It was a nice feature when I briefly flew the G1000 172SP.

But the shortcomings of EFIS software aren't alone. As a mechanic I was continually amazed at things like the wheel, tire and brake technology still being used on GA airplanes, even brand new ones. Grease seals made of felt, which was abandoned by the automobile industry about 100 years ago. Felt has to be greased to be of any use whatever, and the grease attracts dust, grinding grooves in the seal shoulder on the axle, and the felt can't keep water out if someone squirts water at the wheel hub while washing the airplane. Cleveland finally started using a nitrile seal in nosewheels, but the mains are still felt. They'd have to come out with a new wheel casting and some other stuff to convert the mains properly. Maybe they'll do that when they finally decide to put a seal between the wheel halves so that we can use tubeless tires, which some tire manufacturer would have to start making, and make it a radial while they're at it. When did tubes disappear in auto tires? 1966, maybe? And bias ply tires? They were pretty much gone by 1976. GA airplanes? Maybe never. And Cleveland brakes are still using 1940s O-ring technology, without a piston boot, so that the aluminum caliper bore corrodes and the O-ring takes a set and starts leaking. Auto calipers have always had quad rings made of good synthetic stuff and boots to keep dirt and water out.

Rant off. Before I think of some of the other nonsense I've seen in new airplanes. Back to the static port thing....
 
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