The International Cessna^® 170 Association

What are guys using to mount the compass when removing the strap on the windshield? Thanks Mike

My IA fabricated a mount out of .032 aluminum which was a U-shape bracket attached to the top middle of the instrument panel that attached to the front and back of the compass with a standard 2-1/4" instrument hole on the front and cut-out on the back side of the compass to accept the lower two rear screws.

Mine went in the panel, over the right glove box.

I replaced my panel mount compass with a S.I.R.S. Navigator compass. The windshield mount comes with a sticky pad that sticks right to the glass. Works great.
http://www.sirs.co.uk/aircraft

Mine is on the glareshield, just like the picture above. In lieu of fabricating a bracket, PAI makes a very nice on that has a standard 2.25" cutout and grommet dampened holes. They are about $20 or $25 from Spruce and the others online. Yeah, it's only $2 worth of aluminum and an afternoon of time, but if you don't have the proper instrument punch and templates it might be worth it as getting the holes perfect and a professional appearance is a PIA.

You may want to duct tape the thing up there and go out and rough swing it first though. I was having fits getting mine to swing (due to what turned out to be a magnetized engine mount). With no way to degauss the entire engine mount, I ended up having to use a compensator balls. They worked great, but are ugly.

DEM

What do you use a compass for?

Regulations require a "magnetic direction indicator".

I haven't used one in many years. But it's there just in case.

edbooth wrote:What do you use a compass for?

To pass ramp checks. I just make sure that I point the airplane North before they walk over so it reads right

It's a real PITA to swing one. Sometimes it takes all day. Worst part is getting tail up for every heading check.

With the pervasiveness and reliability of GPS, I wish they'd just do away with the compass requirement already.
At any time, I have 4 different sources of GPS data with me. After 2020, nearly every aircraft will have a GPS source (ADS-B)

I can not think of a situation that would require me to attempt a magnetic heading with a compass. Every argument for keeping a compass in the airplane seem to center around Armageddon, WWIII, Zombies or the Government deciding to turn the satellites off.

Regardless of how many receivers you have, there is only one source of GPS navigation, and that is the satellite constellation. The Navy recently had a planned outage in the southwest to test a GPS jamming system, but the alphabet groups got them to postpone. There is at least one model of airplane that wouldn't be able to fly at all in a GPS outage due to its GPS-augmented stability system. Too many eggs in one basket to suit my taste.

When I'm flying cross country, in addition to however many GPS receivers I have operating, I have my VOR and DME receivers tuned to the closest station, and when I had an ADF and Loran, they were tuned in too. In case that all goes to hell in a hand basket, I keep the DG synched up the compass.

cessna170bdriver wrote:Regardless of how many receivers you have, there is only one source of GPS navigation, and that is the satellite constellation. The Navy recently had a planned outage in the southwest to test a GPS jamming system, but the alphabet groups got them to postpone. There is at least one model of airplane that wouldn't be able to fly at all in a GPS outage due to its GPS-augmented stability system. Too many eggs in one basket to suit my taste.

When I'm flying cross country, in addition to however many GPS receivers I have operating, I have my VOR and DME receivers tuned to the closest station, and when I had an ADF and Loran, they were tuned in too. In case that all goes to hell in a hand basket, I keep the DG synched up the compass.

OMG, why would you ever remove ADF from your plane? What happens if all the GPS satellites AND all the VORs go down at the same time? What will you have to navigate with? You need redundancies.

If one of your multiple GPS systems has ADAHRS, the "magnetic direction indicator" requirement is filled and the compass can be removed.

I have a vertical card compass in my plane. It has restored my belief in a compass as it works well for my VFR flying. So much so that I've delayed replacing my AN DG. It's simple reliable technology. It's the whiskey compass that I think is seriously outdated.

Does anyone remember pilotage with a , what do you call it..... Paper Sectional??????