Getting Aircraft IFR Certification with EFIS

[DGlaeser]

Originally Posted by Ken

Thanks, Stein
I am going to clarify with GRT. I understood that I didn't need the annunciator for the SL-30 but I would need it for the GNC-300. I have the Sport 200 and 100 with an internal GPS in the 100. Could it be that I cannot get annunciation for nav AND 2 gps in the EFIS?
Ken

The Sport does not have any annunciation, so I have an AK950L annunciator panel. The 'L' means it doesn't have the switches that allow a GPS and VOR to share the same CDI so it costs less. It's not required in this case because the Sport displays CDIs for both the GPS and VOR simultaneously.

[Garage Guy]

Originally Posted by SteinAir

I guess I'd encourage you to get a newer generation unit if you intend a nice glass panel IFR setup...

No question a GNS430W would be nicer, but I'm not feeling that rich at the moment. I guess if the EFIS is handling CDI display, I can make a little separate annunciator panel easily enough, and lose the MD40.

--Paul

[USCANAM]

I guess now we can go fly again in the rain, clouds, and mire. Well, not at least until I waterproof the plane.

Here's what we learned today.
Static system. Make it tight !! Do not use the Van's kit of flimsy tubing, slip on T fittings, and rivets for static ports. This will work fine for VFR, but it will not stand the pressures of the IFR test. Took well over an hour to track down the errors of my method of installation.
According to Terry (my avionics tech) the static cannot leak more that 100 feet per minute, but with his test equipment, he said we would never reach 20,000 feet if there were any leaks.
My static source feeds 3 instruments; 1 backup airspeed, 1 backup altimeter, and the Blue Mountain Sport EFIS.
Therefore I have 2 tees in the line, and one was not tight, causing a small leak. Thank goodness for the external inspection panels I fabricated. Would not have been a pleasant job trying to do from under the panel.
Oh, and did I mention that one of the lines had come off the "rivet" static port. That required removing the rear fairing.
Just to stop any further delays, even after all the static lines were OK'd, he attached a line directly into the EFIS.

We started to test the system at designated altitudes, and it was within 30 feet until reaching 6000', where the error became about 1000ft. Terry had an idea as to what the problem might be, and a quick call to BM confirmed that the airspeed needed some pressure to make the unit think it was flying????. So he hooked up the airspeed calibrate line.
Terry would then set the test equipment to a designated altitude, and I would record what the AD number was in the Sport, even though the EFIS altimeter was reading wrong.
Then I went into the system and changed all the AD numbers to match the recorded ones for that particular altitude.
Tested again this time doing the transponder at the same time right up to 20,000', and the error was zero feet.
What should have taken about 2 hours was about 4 1/2, so I paid accordingly.
Next time with a better static system and new ports that I'm going to machine, it could be even less than 2 hours.

In summary, if my static system is done right, in 24 months, all Terry will have to do, is remove the static line to the backup airspeed (easy with the tip-up), connect his equipment to that line, compare altitudes to the test equipment, the EFIS and the transpnder, and we will be out of there.
If the electronics have wandered a bit, it's a simple matter to re-calibrate.
Then all that's needed is the logbook entry with test results.

I've been working with Terry since 1989 on projects, and he seems to have a good handle on working with the EFIS. If you're in the New England area, and would like to talk with him, I'll be happy to put you in touch with him.
Whee, it's over!!!
I hope this enlightens you a little bit. As Stein said, it's no big deal, but everything has to be right to start with.
Jack

[Kevin Horton]

Originally Posted by USCANAM

I guess now we can go fly again in the rain, clouds, and mire. Well, not at least until I waterproof the plane.
Next time with a better static system and new ports that I'm going to machine, it could be even less than 2 hours.

Keep in mind that the contour of the outside of the static ports affects the airflow pattern at the ports, which affects the air pressure at the ports, and hence the accuracy of the static system. The bump in Van's pop rivets appears to be important to achieve acceptable accuracy. Many people have tried flush static ports, only to find that the airspeed and altimeter read too low. Glueing on simulated rivet heads over the port orfices fixes the problem.

If you plan to machine your own ports, and you want the same accuracy as with Van's pop rivets, you need to make ports that have the same external shape as the rivets. The area in the close vicinity of the static port is also critical, so you want to have a flat surface as it transitions from the skin to your port, then the bump where the port orifice is.

[USCANAM]

Originally Posted by Kevin Horton

If you plan to machine your own ports, and you want the same accuracy as with Van's pop rivets, you need to make ports that have the same external shape as the rivets. The area in the close vicinity of the static port is also critical, so you want to have a flat surface as it transitions from the skin to your port, then the bump where the port orifice is.

Thanks Kevin
Will keep that in mind. I use 7075 aluminum, and should be able to keep the heads thin and small, very close to the rivet head size. Only difference will be on the inside, where I'll have a thread on the shaft for a nut, and a long extension to slide the tube over.
Thanks again
Jack

[USCANAM]

Here's what we came up with for the new static ports.
Heads are .041" thick. Shaft for tubing is .020" oversize. Will heat tube and slide over.
Thread is 1/4" course.

By USCANAM
Jack

[sneedrv-6]

I had a full IFR Cert. done on my plane and I have the little sticker that says everything was inspected as per FAR 43. My question is, where do I put this sticker? assume the aircraft logbook, but I do not keep the aircraft logbook in the plane. So if I got ramp checked how do I show the plane is current as far as FAR 43?

Thanks a bunch,

Jason

[Mel]

The sticker goes in the aircraft log. It does not have to be "in the aircraft." It just has to be available within a reasonable period of time.

[SteinAir]

There may be a bit of confusion here...on an IFR cert there are two things that should be labeled when finished. #1 is the aircraft logbook, and #2 is the system/component that was tested. Some shops(like us) use stickers for both, but some will just signt the logbook and give you the sticker to put on the encoder/altimeter or whatever.

Either way, the Logbook needs to have something in it like Mel says. If your tech put a sticker on the altimeter than great, but not as important as the logbook.

Cheers,
Stein

[flion]

So I should have gotten stickers from my tech for the transponder, EFIS, altimeter, and airspeed? And then fished behind the panel to apply them? I noticed that Aerotronics applied stickers when they certified their install and I'm guessing you do, too, Stein, but I'd bet that the field technician rarely does. I only got two stickers to apply in my airframe logbook and the DAR was happy with that.

I'm assuming that the reason I did not receive logbook stickers from Aerotronics was because they only tested the panel components; they could not certify the complete installation. Hence the check after I completed the panel install.