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Card Compass and mount


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From a quick forum search it looks like the general mooniac opinion is that the Precision card compasses are the best.

Im looking at this one. https://m.aircraftspruce.com/catalog/inpages/vertcard_compass3.php

Im about to pull the trigger on one and just wanted to confirm everybody still feels that way.

also wondering which mount to get.  There are 3 options.

My only other thought was can I put this in the panel?  I have a free 3" hole I could use.  My thought is you cant put a compass with all that electronics and metal surrounding but wanted to confirm with you guys. 

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Edited by TheTurtle
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I've been looking at this compass too. Will be very interested to know the verdict and results. My current wet compass sometimes gives funny results which might be just due to my Mooney still accelerating. I was suspecting some magnetic interference.  The C-planes I used to fly reached their cruise speed soon after leveling off. If this compass is really better than the old fashioned wet ones I wanna get me one. 

My old one started dripping fluid too once.

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Just now, pinerunner said:

I've been looking at this compass too. Will be very interested to know the verdict and results. My current wet compass sometimes gives funny results which might be just due to my Mooney still accelerating. I was suspecting some magnetic interference.  The C-planes I used to fly reached their cruise speed soon after leveling off. If this compass is really better than the old fashioned wet ones I wanna get me one. 

My old one started dripping fluid too once.

mine was nearly out of fluid when I bought the plane.  Its really inaccurate in certain direction and only less inaccurate in others.  Any it vibrates and sloshes around.  My feeling is whiskey compasses suck in a plane.

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Just now, M20Doc said:

Why not just repair your Air Path compass and swing it? A C21-100 diaphragm is $5.00

Clarence

I dont want to remember ANDS ;) and the sloshing around and vibration, I just dont like whisky compasses.  Plus mine is beat to death looking and kind of bugs me every time I see it.  I suppose I could paint it or something and replace the compass variation card with a new one, but I was planning on putting in a card style since I bought it.

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From a quick forum search it looks like the general mooniac opinion is that the Precision card compasses are the best.
Im looking at this one. https://m.aircraftspruce.com/catalog/inpages/vertcard_compass3.php
Im about to pull the trigger on one and just wanted to confirm everybody still feels that way.
also wondering which mount to get.  There are 3 options.
My only other thought was can I put this in the panel?  I have a free 3" hole I could use.  My thought is you cant put a compass with all that electronics and metal surrounding but wanted to confirm with you guys. 
Capture.JPG



You want this one.

http://www.aircraftspruce.com/catalog/inpages/pacmovmn.php

5b347572e3cba8c2011a48773c3334ae.jpg


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Turtle, 

I just had one put in my bird. There is a chance that you might need compensating balls which would add to the cost. Mine barely passed when they did the compass swing and didn't need the balls. I like it, it's like a mini DG and I think would be a better back up in the soup if the DG failed. Here's a bad pic but if you zoom in you can see it has the same mount as Marauder posted.

IMG_0099.JPG

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No matter which magnetic compass you use... ANDS is still going to be part of the math...

The vertical compass is an ordinary magnetic compass with a gear driven vertical card...

My 65C had huge interference problems caused by the magnetic shadow of the center tube.  The balancing balls would be a probable solution for that as well...

Later planes got a SS tube in that location...

The nice part about the vertical card is the direction of the card matches the direction of the turn.  This makes the ANDS a bit easier to deal with...

PP thoughts, only.  I could be completely out to lunch on this...

Best regards,

-a-

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I have flown with my Precision PAI-700 for 20 years. It has some of the ANDS effects but no where close to what the old wet compass had. With two Aspens providing magnetic readings, the old Precision has been relegated to a checklist item to cross check the Aspens.

9f156f2d21784e660e9954e2487a9771.jpg


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Why would you need to remember ANDS in a Mooney anyway? ...unless like me you're soon to be doing a checkride. Just sync the DG and turn with that. While technically legal my compass deviation card has such large and varying values that it's not possible to use it to know when to roll out of a turn anyway.

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I bought my E with the vertical compass in it and I exchanged it for a SIRS within a year. If, like me, you have the original «flat nose» windshield, the vertical card will be in your way all the time, especially if you need to install those «magic balls» to stabilize it.

After getting a few scars from that vertical card, I got rid of it, bought a SIRS and lived happily ever after...:)

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I've got the vertical (came with the airplane) and could take it or leave it for the old style. It makes no difference to me.  

On a compass swing all headings on the card  need to be within 10 degrees of the compass rose to be signed off. 

On a 727 the wet compass folds away up in the center of the windshield. Its a prizefight item and I know of one check ride busted that when the Check Airman  had them pull it out to use it - it was GONE, stolen, missing, not there. Aircraft technically unairworthy, not legal to fly. Caused quite a stir at the airline. 

 

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On the Robinson Helicopters the Vertical Card compass is standard equipment. With all that helicopter shaking it makes sense. You can aim the helicopter to a heading as good than with a gyro. Many of the R22s have no gyros but the Vertical compass.

When I first installed my in the original compass location it was a little bit annoying for visibility. I later on relocated it down one mounting hole and is now perfect for overall view. I have a 1982 M20J with non magnetic center post. This made it easy for calibration, in fact easier and more accurate than the previous wet compass. I found better correlation with the DG than when I had the wet compass.

José

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I just mounted the new one using the old whiskey compass mount.  Didnt have to drill out the poprivets that way.  Its pretty far back towards the windows and not in the way at all.  Took all my inspection panels off for annual today so once thats done Ill go swing it and see if I need the compensation balls.

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