Safeair static ports

Captain Avgas · #1 12-17-2005, 12:41 AM

I'm interested in using the Safeair static ports (the Vans pop rivet really is abysmal). I have looked back through the archives and some RV builders have reported not-so-good results with similar ports sold by ACS. There seems to be a feeling that if the port is flush there can be static instrument errors of up to 10%.

The safeair port actually protrudes about .015 to .020 past the skin but if it installed with too much sealant then it may not protrude at all.

I contacted Safeair and they say they have sold "hundreds" of these static ports and not one person has contacted them to complain or requested a refund.

If you are one of the "hundreds" of pilots flying specifically with a Safeair pitot I would like to know if you are getting accurate readings and if you would recommend this product.

Kevin Horton · #2 12-17-2005, 07:58 AM

I believe the vast majority of RV flyers simply have no idea whether their static ports are producing an accurate static pressure or not. The tests that most people do look at the airspeed indication system as a whole. If all you do is flight tests to see how accurate the indicated airspeed is, you have no way to differentiate between ASI instrument error and static port position error.

You might have an ASI that reads 5 kts low, and a static port that gives a 5 kt error in the other direction, and all you see is a perfectly accurate indicated airspeed. Someone else could have the exact same static port, with an ASI that reads 5 kts high, and they'll see a 10 kt error in the indicated airspeed. Pilot #1 believes his static ports are perfect. Pilot #2 thinks his static ports are pieces of junk. Or maybe he thinks his ASI has a 10 kt error. Or more likely he thinks he just built a real fast RV, as he gets higher indicated airspeeds than his friends. And the head winds are always higher than forecast, judging by the ground speeds he gets.

The only way to know how accurate the static ports are is to also measure the ASI instrument error. Any reports on static system accuracy from someone who hasn't also measured their ASI instrument error are worthless.

markscogg · #3 12-17-2005, 06:34 PM

I have the Van's pop rivet static ports. They are tied together, with a single 3/16"(?) inside diameter plastic hose running to the panel.
The altimeter and VSI "hunt" or waiver the smallest bit in flight.
I have always wondered it the static ports or plastic line were not up to the job, and caused this problem.
???
Mark
RV-6

Ironflight · #4 12-17-2005, 08:01 PM

I mentioned on a similar thread the other day that I was using the simple Van's pop rivet static port, and that I have remarkably good results in terms of airspeed accuracy. Kevin is abolutely right that unless you know the calibration of the ASI, measuring the rest of the system is pretty useless. Since I was going to do the typically anal engineer's flight test program, I had my ASI checked before installation, so I know it's accuracy and have removed that from the equation.

Given that, I think that the reason the Van's ports are satisfactory is simple statistics - 4400 (and counting) airplanes have flown from Van's kits, and I'd bet that a large majority of them use the "factory" locations and installation. The pop's are really pretty silly, but elegantly simmple, and well....they work! Of course, I completely trashed the factory pitot tube and went with the Piper blade, so I am hardly preaching blind adherence to the plans...I guess consistency really is the hobgobblin of....well, you know...

(The funny part of my installation is that I actually PULLED the pop rivets, then had a heckuva time getting the mandrel out without damaging the port. That's when someone told me I was just supposed to push the mandrel out without pulling the rivet, and glue the thing in place. Van's instructions leave much to the imagination...)

Paul

N941WR · #5 12-17-2005, 09:52 PM

I bought the SafeAir static ports and then mounted them on the outside of my fuselage. The reason being that I have hear a good bit about the flush mounts not working so well and figure I can give up 1/4 of a knot by mounting them on the outside.

Regardless of how you mount them, they seem like a very good product and everyone who has looked at my fuselage (Note, I'm not flying yet so they may not work.) has been impressed by the quality of the SafeAir ports.

Captain Avgas · #6 12-18-2005, 06:03 PM

Surely there must be some-one out there who is flying with the Safeair static ports who could provide a comment on their performance.

kens_cockpit · #7 12-26-2005, 09:33 PM

Quote:

Originally Posted by Ironflight

(The funny part of my installation is that I actually PULLED the pop rivets, then had a heckuva time getting the mandrel out without damaging the port. That's when someone told me I was just supposed to push the mandrel out without pulling the rivet, and glue the thing in place. Van's instructions leave much to the imagination...)

Paul

I'm about to install the rivets. I also would have pulled them unless I'ld read this thread! Thanks Paul! Anyone with photos of the installation (closeups) it would be helpful

Ken Stanton
Fuselage and all sorts of things