Compass Deviation Card AWOL

That actually is not a legal correction card as it doesn't state whether radios were on or off.
FYI: the radios on/off and engines running requirement was from Part 23. The compensation requirements from the CAR 3/4 days was different and didn't require that info on the correction card hence the simple card above.
 
This is an absolutely critical piece of aircraft information that is necessary for safe flight. Even a degree error would cause you to be miles away from where you think you are when flying a light plane across the Pacific Ocean with only your compass to guide you. It's little wonder the FAA is so strict in its requirement for an accurate compass swing on every aircraft, well worth the $100 or more for it to be done correctly and precisely. Anyone willing to fly an aircraft with a missing or inaccurate compass correction card is an accident waiting to happen.
 
This is an absolutely critical piece of aircraft information that is necessary for safe flight. Even a degree error would cause you to be miles away from where you think you are when flying a light plane across the Pacific Ocean with only your compass to guide you. It's little wonder the FAA is so strict in its requirement for an accurate compass swing on every aircraft, well worth the $100 or more for it to be done correctly and precisely. Anyone willing to fly an aircraft with a missing or inaccurate compass correction card is an accident waiting to happen.

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I am pretty sure not... My friend who is missing the card is laughing and wondering why this little card is required for something that he doesn't look at ever... and wonders why even in the event of a complete electrical failure if he would use it since he has an EFD/AHRS with a battery backup that lasts much longer than he would be able to safely land in the event of said electrical failure.
 
I am pretty sure not... My friend who is missing the card is laughing and wondering why this little card is required for something that he doesn't look at ever... and wonders why even in the event of a complete electrical failure if he would use it since he has an EFD/AHRS with a battery backup that lasts much longer than he would be able to safely land in the event of said electrical failure.

Because the ability for the FAA to react to anything is slow, even on a geologic time scale.
 
I am pretty sure not... My friend who is missing the card is laughing and wondering why this little card is required for something that he doesn't look at ever... and wonders why even in the event of a complete electrical failure if he would use it since he has an EFD/AHRS with a battery backup that lasts much longer than he would be able to safely land in the event of said electrical failure.
It’s entirely possible that your friend could have the compass removed, since he has another “magnetic direction indicator” as required by 91.205. He’d have to research the certification basis for the airplane to determine whether his fancy gizzies meet those requirements, and it’s also entirely possible that his fancy gizzies require the other compass to remain.

if it is legally removable, I’d bet that it costs more than $150 to find out. ;)
 
It’s entirely possible that your friend could have the compass removed,
That would be the $64K question. Since Garmin and others can't seem to get the mag compass removed under their STCs, it would be interesting to know why not.
 
That would be the $64K question. Since Garmin and others can't seem to get the mag compass removed under their STCs, it would be interesting to know why not.
The $.50 follow up question would be, “have they even tried?”
 
I am pretty sure not... My friend who is missing the card is laughing and wondering why this little card is required for something that he doesn't look at ever... and wonders why even in the event of a complete electrical failure if he would use it since he has an EFD/AHRS with a battery backup that lasts much longer than he would be able to safely land in the event of said electrical failure.

Yeah, I was hoping it was tongue-in-cheek. I wouldn't be trying to follow a whiskey compass heading for any large distance and hope that I'd end up close on the other end, especially in turbulence. I understand its use in IFR if worse comes to worse, but if I'm VFR it's only used to reset the vertical card gyro periodically and I'm not referencing the deviation card anyway, lol.
 
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Yeah, I was hoping it was tongue-in-cheek. I wouldn't be trying to follow a whiskey compass heading for any large distance and hope that I'd end up close on the other end, especially in turbulence. I understand it's use in IFR if worse comes to worse, but if I'm VFR it's only used to reset the vertical card gyro periodically and I'm not referencing the deviation card anyway, lol.
Anyone who can read either the magnetic compass or the DG to an accuracy of 2 degrees is a better man than I. It blows my mind that guys like Lindbergh and Corrigan managed to cross the ocean 30 hours with just a magnetic compass.
 
Yeah, I was hoping it was tongue-in-cheek. I wouldn't be trying to follow a whiskey compass heading for any large distance and hope that I'd end up close on the other end, especially in turbulence. I understand it's use in IFR if worse comes to worse, but if I'm VFR it's only used to reset the vertical card gyro periodically and I'm not referencing the deviation card anyway, lol.
That’s why the airlines are required to be able to reliably fix their position at least once an hour.
 
The $.50 follow up question would be, “have they even tried?”
I read somewhere that Garmin had tried. And for some reason I think it has to do with the mag compass being the only installed, completely independent indicator in an aircraft. A fail safe device. What's ironic, back in the early CAA/CAR days if an aircraft operated VFR within 100 miles of a fixed base there was no mag compass requirement. But on aircraft that operated VFR on an unlimited basis mile-wise a compass was required. However, I think if someone were to call an ACO and get the right person, they might be able to ask why or why not to remove the mag compass.
 
I read somewhere that Garmin had tried. And for some reason I think it has to do with the mag compass being the only installed, completely independent indicator in an aircraft. A fail safe device. What's ironic, back in the early CAA/CAR days if an aircraft operated VFR within 100 miles of a fixed base there was no mag compass requirement. But on aircraft that operated VFR on an unlimited basis mile-wise a compass was required. However, I think if someone were to call an ACO and get the right person, they might be able to ask why or why not to remove the mag compass.
Part 25 requires an “uncompensated” magnetic compass but one of the airplanes I teach was certified with a separate AHRS system instead, so obviously it can be done.

I’d bet that with Garmin it was more a case of too much money for too little return than an absolute “can’t be done”. Of course, it may have been too much money to get their equipment to the level of reliability required.

And yes, you’d have to get the right person at the ACO.
 
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Anyone who can read either the magnetic compass or the DG to an accuracy of 2 degrees is a better man than I. It blows my mind that guys like Lindbergh and Corrigan managed to cross the ocean 30 hours with just a magnetic compass.
My experience (limited to less than 4 hours at a time) is that the pilot-induced errors seem to cancel themselves out.

but when you consider that Lindbergh probably didn’t expect to be exactly on course when he made landfall, he’d probably agree that 30 hours of DR isn’t going to be accurate (or even precise) navigation.

Corrigan, on the other hand, ..... ;)
 
I wouldn’t want to be the guy that signed off on removing something as cheap and simple as a mag compass. What’s the harm in having one?
 
I wouldn’t want to be the guy that signed off on removing something as cheap and simple as a mag compass. What’s the harm in having one?
If it’s not required, I’d have no problem signing off the removal if I were qualified to do so.

It’s the level of risk the pilot thinks acceptable that I’d question...especially after training with a guy who lost all three compass systems (along with every other electron in the ship's electrical system) on a transPacific flight. The fact that it was night time made it substantially easier for him, think.
 
I wouldn’t want to be the guy that signed off on removing something as cheap and simple as a mag compass. What’s the harm in having one?
Probably the same harm in keeping an ADF in your panel. A mostly useless (in terms of normal usage) device unless you're in a situation where it's your only option. Extra cost to have a compass swing performed, extra weight (hey, every bit counts) and possibility of fluid leaking. On a glass panel or non-vacuum panel, I would imagine it never gets looked at other than initial check.
 
I'm talking about if I'm the guy in the Faa. What's the win for me to agree to removing such a cheap and simple backup instrument that's been required for so long?
 
I'm talking about if I'm the guy in the Faa. What's the win for me to agree to removing such a cheap and simple backup instrument that's been required for so long?
The eternal gratitude of the entire free world. ;)

The guy in the FAA never wins, but seldom loses. He simply ensures compliance with the regs.
 
Anyone who can read either the magnetic compass or the DG to an accuracy of 2 degrees is a better man than I. It blows my mind that guys like Lindbergh and Corrigan managed to cross the ocean 30 hours with just a magnetic compass.

Missing Europe would be pretty hard :D
 
That’s why the airlines are required to be able to reliably fix their position at least once an hour.

Here is a panel shot of a Constellation formerly in transoceanic service with TWA. That isn't much of a panel. Of course the navigator's station was not in the cockpit, it was back dangerously near the bar....

-Skip
 

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Well played, sir. Well played.
 
I have an Excel file that will generate and print the card in the correct size if you'd like it.

I know "everyone is joking ha ha" but seriously, nobody uses those numbers. Print nonsense, stick it under the compass, fly on. The squawk fairy works in mysterious ways.
 
Is it about a 2 1/2" X 1 1/2" card? Maybe laminated? With the date of the last recorded compass swing from the aircraft logs? Still asking for a friend... who may or may not have created one just like that...
 
I had to take wife in for Dr. Visit today. Swing by the hanger and took a photo of my card. Looks like 2 more under the tape.
Look like last swing was 2007 .
 

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How could you fly the plane and read that card and the compass while you’re turning? If you don’t have the numbers on the card memorized, you’re just a danger to everyone. I’m shocked. Shocked I say.
 
My first jet seat time was starting the engines and recording the headings during compass swings. It felt pretty cool at the time.
 
This is an absolutely critical piece of aircraft information that is necessary for safe flight. Even a degree error would cause you to be miles away from where you think you are when flying a light plane across the Pacific Ocean with only your compass to guide you. It's little wonder the FAA is so strict in its requirement for an accurate compass swing on every aircraft, well worth the $100 or more for it to be done correctly and precisely. Anyone willing to fly an aircraft with a missing or inaccurate compass correction card is an accident waiting to happen.
Wait, are you joking or not? Can’t tell.

Next time I am flying my VFR panel 1966 Cessna 150 hundreds of miles over the Pacific Ocean with only my compass, I’ll let you know. Till then, I don’t think the compass is the most important device in my plane. 99.99% of the time my IPad (or sectional and roads) is a better nav device and the rest of the time (0.01%) I’ll just admit I am lost and call ATC for help.
 
Wait, are you joking or not? Can’t tell.

Next time I am flying my VFR panel 1966 Cessna 150 hundreds of miles over the Pacific Ocean with only my compass, I’ll let you know. Till then, I don’t think the compass is the most important device in my plane. 99.99% of the time my IPad (or sectional and roads) is a better nav device and the rest of the time (0.01%) I’ll just admit I am lost and call ATC for help.

Whether or not I was being facetious in my post can be determined by a highly scientific poll of every pilot on this board being asked if they have ever, I say ever, in their entire flying experience, used the information recorded on their deviation card in flight. Write the number of pilots who would have but couldn't read the faded numbers written on the tiny card and record it on a separate piece of paper and fold it up. Take the number of pilots who respond in the affirmative and divide it into the number of pilots who respond in the negative. Take the quotient and find it's square root and multiply that by 3. If the answer you get is a negative number, then you need to get a better calculator. Now take the folded up piece of paper and if the number written on it was greater than one, I was joking. Now ask me if learning the Morse Code should be a requirement for every pilot.
 
Years ago I alighted my electric fighter jet for the final time, and said, "That'll do, pig." Traded my Nomex pajamas for dungarees and headed out to yonder grass strip.

TOLD the folks there I would be taking their tired old Cessna for the insane amount of shekels they asked, and if a young whipper-snapper needed to accompany me, so be it, better be the quiet type.

Upon entering the COCKPIT of said Cessna (flight deck my Aunt Sadie) I noticed something wet and foreign bobbling on the glare shield. Frightened as I was to see such an ancient sorceress from the sea, I ripped it from it's grip on my surly steed and threw it across the tarmac, shouting "If God had wanted an aviator to fly with reference to magnetic fields, He would surely have given Adam a digital Magnetometer instead of an apple bob!"

Young whipper-snapper, staring at me, quite agog, was ready to leave the COCKPIT at that point. "Don't worry, young friend, for I have brought forth with me the Stratux, complete with AHRS and GPS. All is well."

Magnetic demons having been sufficiently vanquished, we set forth upon our flight, slipping the surly bonds until such time we had to return, whence we reaped many carnal benefits as victorious warriors of the sky.

I later saw a hapless young warrior on the tarmac, arse over tea kettle, searching below the seats of his COCKPIT for some sort of paper, I know not why. Seeing such a noble warrior in such a state made me want to weep. But of course, I did not. I instead sought (and found) further carnal glory.

Huzzah! :cheers:
 
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Plus, it goes good with cheeseburgers.....
 
Now ask me if learning the Morse Code should be a requirement for every pilot.
Somehow every Boy Scout did in the late 40s early 50's. I do remember following morse code to airport back in 1970 . My early student pilot days.
Now after looking at my compass card , reading regulations , Wondering if my aircraft is VFR legal.
But I do have IPad / ForeFlight and the sticky thing with GPS stuck to the side windscreen. :D
 
This is an absolutely critical piece of aircraft information that is necessary for safe flight. Even a degree error would cause you to be miles away from where you think you are when flying a light plane across the Pacific Ocean with only your compass to guide you. ...
So now we know how Amelia got lost.
 
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Did he check the Mx logs? Some people are anal enough to put a copy or document it in the logs.
 
Because the ability for the FAA to react to anything is slow, even on a geologic time scale.

True.
Well, unless you joke around about taking cash for flight training when you're not a CFI.

Then they are the Fast Acting Association.
 
@catmandu I cried a little when I read that. Just a little creeper of a tear out of my left eye, but I still had to turn my head and hide my emotions lest my 10 year old see the glistening moisture and shame me. Best piece of writing I have read all year. Even better than the FAR/AIM, IR ACS and Instrument Procedures Handbook.

@ anybody else who cares - I found it. I found the little raffle-ticket-looking thing. Not only was it under the seat, it was under the carpet under the seat. But I found it. I mean my friend found it... No... it was me all along. I found it. It looks like something older than the Dead Sea Scrolls. Printed on papyrus or whatever parchment was used pre-papyrus.

Here is a picture of it:

IMG_8582.JPG

That is about as good as the resolution gets. I haven't tried to use my wife's DSLR/fancy/expensive camera yet to blow it up more, but there she is. Proof that this aircraft has a compass deviation card. I will use my all the knowledge I learned watching CSI to enlarge this and put the numbers into a nice, new, laminated card. And I'll even laminate this one just in case the FSDO wants to see an original if I get ramp checked.

Honestly, I felt a little sad when I found it this morning. Like the end of a quest. What else is there in life now that I have this ancient artifact in my possession?
 
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