Geoff Posted October 22, 2014 Report Posted October 22, 2014 My original compass has sprung a leak and I'm looking at replacing with a smaller SIRS unit. Anyone have any experience (good or bad) with these units in a Mooney?
DAVIDWH Posted October 22, 2014 Report Posted October 22, 2014 Just replaced mine with a vertical card. Enough with the leaking whiskey. Also, the card compass is no longer subject to the new FAA regs. concerning the presence of alcohol in the cockpit.
grami-air Posted October 22, 2014 Report Posted October 22, 2014 In 2000, I replaced a leaking compass with an SIRS Navigator in my F model. Sold the F early this year but during those 14 years I never had a single issue. Excellent product.
Ftlausa Posted October 23, 2014 Report Posted October 23, 2014 I would recommend you check out the vertical compass option. I just installed one, and it is better in my opinion.
Geoff Posted October 23, 2014 Author Report Posted October 23, 2014 Grami air, Did you have any issues with high compass deviations? Seems like the avionics guy is saying the compass is showing a 40 degree deviation without the avionics on.
The-sky-captain Posted October 23, 2014 Report Posted October 23, 2014 I bought a SIRS. A couple years ago and have had no issues.
BigTex Posted October 23, 2014 Report Posted October 23, 2014 I replaced my vertical card compass with a SIRS to resolve issues with a magnetized roll cage. It did the trick and couldn't be happier.
Geoff Posted October 23, 2014 Author Report Posted October 23, 2014 Anyone have pictures of the installation?
Ned Gravel Posted October 23, 2014 Report Posted October 23, 2014 +1 for the Sirs. My whiskey compass would not stop vibrating and I had the prop dynamically balanced to less than 0.02. Clarence's guys told me the verical card just would not swing properly during an annual so I asked him to put in a Sirs compass. Same installation as Big Tex. Works great.
Piloto Posted October 23, 2014 Report Posted October 23, 2014 I have a vertical card compass on my M20J and I am very happy with it. Specially when in turbulence, much easier to read than a wet compass. I think the magnetization issue is more related to pre M20J models. If you use electric arc welding on the compass structure the structure will be magnetized. However if you use torch welding you do not have the magnetization problem. The vertical card compass is probably more sensitive to structure magnetization because it uses stronger magnets than wet compass. A big magnet will pull to the closest magnetic structure (force interaction) while a tiny wrist magnet will pull to the North (field orientation). José
philiplane Posted October 23, 2014 Report Posted October 23, 2014 The PAI-700 vertical card compasses generally work well for a short time. Then they stick. Not worth installing one if you don't want a whiskey compass. The SIRS is the best compass on the market at this time. Tens of thousands of fleet hours on them with no problems.
Piloto Posted October 23, 2014 Report Posted October 23, 2014 The PAI-700 vertical card compasses generally work well for a short time. Then they stick. Not worth installing one if you don't want a whiskey compass. The SIRS is the best compass on the market at this time. Tens of thousands of fleet hours on them with no problems. Maybe the SIRS is not good enough for helicopters. Since all the Robinson helicopters are equipped with vertical card compass from the factory. And there is more shaking in a Robinson than in a Mooney. José
grami-air Posted October 23, 2014 Report Posted October 23, 2014 Geoff, I did not experience any issues with high compass deviations. Also, If I remember correctly, the fluid in the compass is a silicone fluid and "thicker" than a regular alcohol wet compass, therefore any swings in direcrion are damped much better. When I installed it, I swung the compass on the compass rose whcih fortunately was on the field to complete the deviation card. I mounted the compass in its original location. Like I said, an excellent product, but others seem to have good success with a vertical card as well.
jlunseth Posted October 24, 2014 Report Posted October 24, 2014 I had a vertical card installed in 2009. Works good, but I can't say I use it alot. I fly to the KFC200 which has never failed me.
drapo Posted October 24, 2014 Report Posted October 24, 2014 I changed from a vertical card to a SIRS mainly because the vertical compass took too much room in my cockpit, a M20E with the standard windshield. As far as accuracy, both are very good.
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