Vertical Magnetic Compass

How to keep the Cessna 170 flying and airworthy.

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cpolsley
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Joined: Wed Jan 01, 2003 4:37 pm

Vertical Magnetic Compass

Post by cpolsley »

Whats the opinion of a vertical compass as compared to the whiskey compass? Do they bounce around a lot or are they stable like a DG?
I would like to mount it on the top of the instrument panel.
N2865C
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Post by N2865C »

They are a lot more stable. No bouncing up and down. They still have some lead and lag error, but not nearly as much as a whiskey compass. I had one in my last plane. They are great for the directionally challenged (like me).
jc
John
N2865C
"The only stupid question is one that wasn't asked"
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jrenwick
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Post by jrenwick »

Here's mine:

Image

The vertical card compass seems more stable than a whisky compass, and it's certainly easier to read.

Best Regards,

John
John Renwick
Minneapolis, MN
Former owner, '55 C-170B, N4401B
'42 J-3 Cub, N62088
'50 Swift GC-1B, N2431B, Oshkosh 2009 Outstanding Swift Award, 2016 Best Continuously Maintained Swift
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Roesbery
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Post by Roesbery »

The one I tried was real stable, part of the time, I could turn 45 degrees befor it would move sometimes. Then sometimes it would do a couple 360s while I was straight and level. Took it out, went back to the old way.
AR Dave
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Post by AR Dave »

OK John, you didn't use that as an excuse to show off that gorgeous instrument panel did you? :) Man we've got some nice planes coming to Petit Jean. I might as well start taking pictures of panels & interiors now! :roll:
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blueldr
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Post by blueldr »

Re: Vertical card compasses--- they look neat, but they seem to wear out fast. I've never seen an Air Path wet compass wear out.
BL
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jrenwick
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Post by jrenwick »

AR Dave wrote:OK John, you didn't use that as an excuse to show off that gorgeous instrument panel did you?
:oops: Darn! He's on to me! :oops:

That, and I wanted to figure out how to include a photo in a message....

Thanks for the compliment! :)

John
John Renwick
Minneapolis, MN
Former owner, '55 C-170B, N4401B
'42 J-3 Cub, N62088
'50 Swift GC-1B, N2431B, Oshkosh 2009 Outstanding Swift Award, 2016 Best Continuously Maintained Swift
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170C
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Vertical Card Compass

Post by 170C »

I had one in my C-140, loved it. Put one in my 172-TD a few years back and wouldn't want to go back to the whiskey compass. Easier to read & it follows your turns as does the DG.

And ARDAVE beat me to the punch on John having an excuse to show off his panel. If my panel looked that good I'd put a photo (if I knew how) of mine on the forum!
OLE POKEY
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GAHorn
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Post by GAHorn »

An easy way to read a whiskey compass or AN gyro compass is to remember that if you want the numbers in the window to slide to the right....it's a right hand turn. (So if your present heading is 270 degrees and you want to fly 300 ...then you want that little number "30" to move to the right >>>>
[30 | 29 | 27 | 24 | 21]
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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N3243A
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Post by N3243A »

I agree with Dick. They look neat but mine wore out to the point that is was reading 90 degrees out. The little gimble mechanism that translates the real compass needle to the vertical card is pretty delicate.
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GAHorn
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Post by GAHorn »

That's a common complaint about the vertical card magnetic compasses.....they are fragile and unreliable. There's a service letter issued by the manufacturer (Precision) about installation procedures because so many of them are rendered inoperative merely by handling them during installation.
It seems to me that if the purpose of a magnetic compass is as an all-time reliable backup/primary instrument that we want to work when everything else fails.....then the vertical card version is a hazardous waste.
Last edited by GAHorn on Mon Mar 21, 2005 8:54 pm, edited 1 time in total.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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jrenwick
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Post by jrenwick »

gahorn wrote:That's a common complaint about the vertical card magnetic compasses.....they are fragile and unreliable. There's a service letter issued by the manufacturer (Precision) about installation procedures because so many of them are renedered inoperative merely by handling them during installation.
Wow! I didn't know these things had problems. I'll keep a suspicious eye on mine, and if it looks like it's acting up, I'll replace it with a whiskey bottle -- er, compass. :D

Thanks for the heads-up, everyone!

John
John Renwick
Minneapolis, MN
Former owner, '55 C-170B, N4401B
'42 J-3 Cub, N62088
'50 Swift GC-1B, N2431B, Oshkosh 2009 Outstanding Swift Award, 2016 Best Continuously Maintained Swift
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