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Do i need a compass?
- Thread starter gassman
- Start date
True, but it won't satisfy the requirements for a DAR or FSDO to issue an AWC.
The problem comes when some ill-informed inspector believes that you HAVE to have a "wet compass" despite your EFIS and its own magnetic direction indicator...
Not so! It DOES satisfy the requirements for a DAR or a properly informed FSDO. First off, for daytime VFR, NO instruments are required as part 205 does not apply to experimental aircraft. And your Op Lims will clearly state that for night and/or IFR, you must meet the requirements of part 205 wich uses the term "magnetic direction indicator". It says nothing about the indicator being independent.
And….he was wrong, becaue as Mel noted above, NOTHIGN is required for DVFR ops. The first sentence of 91.205 starts with “For aircraft with a Standard Airworthiness Certificate…..” You have a “Special” Airworthiness, so it doesn’t apply unless called out by your ops Lims (as it does for night or IFR).
He was 100% incorrect.
Ask him to show you the reg that says "wet compass required".
I'm guessing he will not be able to.
And no, magnetic direction indicator does not equal wet compass.
FAR 91.205 clearly states "magnetic direction indicator". Your EFIS will have that and it will show your heading (magnetic). AHARS has a built in magnetometer but you can also have a remote magnetometer like Dynon provides. Even they call it a "remote compass".
I'm guessing he will not be able to.
And no, magnetic direction indicator does not equal wet compass.
FAR 91.205 clearly states "magnetic direction indicator". Your EFIS will have that and it will show your heading (magnetic). AHARS has a built in magnetometer but you can also have a remote magnetometer like Dynon provides. Even they call it a "remote compass".
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In my experiences with the FSDO, I’ve found that they are jacks of all trades, not necessarily experts on EAB. But they are usually reasonable (although not always), and willing to be politely educated. Show them the comments from the DARs, above. Politely remind them that they are only certifying for phase 1, day, vfr only, where 91.205 does not apply. Later, you will self-certify for phase 2. If they persist, well, your choice to give in or fight.
If I get the inspector I think im getting, ive known him for 20+ years and hes a good guy. Hes inspected a bunch of rvs around here so.....hopefully hes still a good guy
If you're going to put in a compass, make sure it's not a Tate's.
There once was a couple, Nancy and Mike Tate, whose lifelong dream was to own a compass company. They scrimped and saved, finally launching Tate's Compass Company.
Their big break came with a massive order: 750,000 compasses for the Boy Scouts. They worked day and night to meet the deadline for the big Jamboree wilderness hike.
Each Scout received a shiny new Tate's Compass.
Problem: Every single one had the colored needle point installed backwards. So when the Scouts faced North... the needle pointed South.
Chaos ensued. Thousands of Boy Scouts got hopelessly lost. It became one of the biggest disasters in scouting history.
The Tate's Compass Company went bankrupt almost immediately.
And from that fiasco came the immortal saying:"He who has a Tate's is lost."
There once was a couple, Nancy and Mike Tate, whose lifelong dream was to own a compass company. They scrimped and saved, finally launching Tate's Compass Company.
Their big break came with a massive order: 750,000 compasses for the Boy Scouts. They worked day and night to meet the deadline for the big Jamboree wilderness hike.
Each Scout received a shiny new Tate's Compass.
Problem: Every single one had the colored needle point installed backwards. So when the Scouts faced North... the needle pointed South.
Chaos ensued. Thousands of Boy Scouts got hopelessly lost. It became one of the biggest disasters in scouting history.
The Tate's Compass Company went bankrupt almost immediately.
And from that fiasco came the immortal saying:"He who has a Tate's is lost."
Yeah, I missed that for VFR only aircraft. I tend to think in terms of IFR capable. My mistake.
But, as you noted, the "magnetic direction indicator" which is an integral part of all modern EFISes is sufficient. No wet compass required. But I'd hazard a guess that a hypothetical EFIS which did NOT have a magnetic direction indicator, but the builder claims that all he needs is GPS heading (not course, but heading, which is not usually available) and the local mag deviation and could thus compute the mag heading would not pass an inspection for night/IFR.
You can argue down that rabbit hole if you choose. I have learned that proving the guy holding all the cards wrong rarely works out well. Cost $20 for a heap compass and everyone walked away happy.
My second fsdo guy said where is your compass. Showed him the language and he said i guess you are right. The efis will be fine. So, definitely not all of them are unwilling to examine the regs more deeply and suspect that second guy is more typical.
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In my case, i had requested the paragraphs for night and ifr. Was unsure if the MDI is required for awc, but in my case the fsdo guy was clear in his mind that it was. I was prepared for the mdi vs compass argument, but not for the awc vs ifr regs. I didn’t understand at the time that the compass was not required for day only and therefore shouldn’t have had to have one untill i was ready for IFR flight.
I haver found most of the FSDO people to be quite reasonable. At one point they were airplane people just like the rest of us.
I went to grad school &/or worked industry jobs with a few folks that eventually went to work of the evil empire. and they're good people. The last time I was in there renewing my CFI the idea was floated that I should consider going to work there. I said no thank you, but If I was 10 years younger I would have considered it.
The problem is that just like in every other aspect if life (honestly, even including VAF), every once in a while you get to interact with somebody who is both opinionated and has to be right at all costs. Unfortunately, in that environment, there is typically no consequence for them for swimming upstream against the policy guidance of their own employer.
I didn't put in a compass, I didn't call ahead and say "do you want me to put in a compass?" I didn't bring it up at the inspection. I had no squawks and was issued my AWC with no issues.
If he had balked at that and been one of the unreasonable few, I could have showed him the reg and if he didn't agree, told him he was on a power trip, pointed out that I've been in this industry a couple of decades longer than he has, went over his head and called a couple of buddies who are higher up the food chain....Or I could have just put in a compass and then taken it back out after he left, while mentally calling him an obstinate bastard
I went to grad school &/or worked industry jobs with a few folks that eventually went to work of the evil empire. and they're good people. The last time I was in there renewing my CFI the idea was floated that I should consider going to work there. I said no thank you, but If I was 10 years younger I would have considered it.
The problem is that just like in every other aspect if life (honestly, even including VAF), every once in a while you get to interact with somebody who is both opinionated and has to be right at all costs. Unfortunately, in that environment, there is typically no consequence for them for swimming upstream against the policy guidance of their own employer.
I didn't put in a compass, I didn't call ahead and say "do you want me to put in a compass?" I didn't bring it up at the inspection. I had no squawks and was issued my AWC with no issues.
If he had balked at that and been one of the unreasonable few, I could have showed him the reg and if he didn't agree, told him he was on a power trip, pointed out that I've been in this industry a couple of decades longer than he has, went over his head and called a couple of buddies who are higher up the food chain....Or I could have just put in a compass and then taken it back out after he left, while mentally calling him an obstinate bastard
sansoneservices
Well Known Member
Whiskey compass? no..
My certified plane still has one, never look at it, wasted real estate
My certified plane still has one, never look at it, wasted real estate
Then those FSDO Guys were wrong. This procedure has always been the rule, at least as long as I've been doing it since back in the last century.
The only change in this respect is that we used to be able to omit paragraphs that don't apply at all. NOT to include or omit what the applicant requests. That changed several years ago.
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A wet compass (whiskey compass) will always work, if you have a Total Electrical failure.
My $.02 this morning
Steve
In the event of a total electrical failure and assuming that my backup batteries are offline, I would still have at least one iPad, as well as my iPhone and Apple Watch. "Magnetic Direction Indicator" is one of my most prevalent redundancies.
This is all you need.....
turbo
Well Known Member
you don't really need a compass rose. find mag n s e and west heading on the ramp with your mag heading from your gps and adjust with that info.
Steve,
Never say, "never" and never say "always"!
I have a metal framed airplane that can't be made useful, let alone accurate. I have hade it degaused, and at least 4 different compasses in it sine 94 and still it is only close on one heading.
I am talking over 90 degrease out, and not even a consistent amount out. I finally gave up trying. Now that I find out I don't legally need it - I may remove it and find something that might work. My iphone compass also is useless in it!
Sam Buchanan
been here awhile
My DAR told me if I had a wet compass it MUST have a correction card.......
So did mine. Then he added, “I know there are no compass calibration circles here. I’m going to look at the wingtip, and maybe when I get back to the cabin the correction card will be filled in.”
I installed one of these on my arm rest as a "reference only" in the logbook and I specifically sited it as pilot removable. Nobody told me that I have to have it, but I felt like I wanted one just in case.
Funny thing is... I recently had a complete power failure. Completely my fault. I programed a new portable laptop to my Vertical Power VPX Sport and in doing so I inadvertantly turned the ALT v SENSE from "always on" to "always off". I had also just installed an EarthX battery. For those of you not experienced with the EarthX battery, it'll give you everything it has until its gone... but it also doesn't drop in volts significantly until it's almost to its failure point. Well that's the perfect storm that happened to me. I was flying a 2 hour flight. I unknowingly took off with the "ALTvSENSE" off on the VPX (which is the electric field wire), and my EarthX gave me everything it could. It was showing normal voltage until about an hour into the flight when it went from 14.1 to 11 volts in less that 30 seconds. I had zero time to troubleshoot. Ultimately my electrical system was out. No battery and no field (alternator) I lost all electrical... but nearly everything in my plane has battery back up. So the only thing I really lost was 2 radios, adsb, and transponder (and trim).
Long story short, after a complete power failure on a cross country... the cheap $5 compass was of completely no use to me.
I got the VPS figured out. I charged up the EarthX. I bought a MunkWorks generator. That should solve me future electrical issues before they happen.... knock on wood.
Funny thing is... I recently had a complete power failure. Completely my fault. I programed a new portable laptop to my Vertical Power VPX Sport and in doing so I inadvertantly turned the ALT v SENSE from "always on" to "always off". I had also just installed an EarthX battery. For those of you not experienced with the EarthX battery, it'll give you everything it has until its gone... but it also doesn't drop in volts significantly until it's almost to its failure point. Well that's the perfect storm that happened to me. I was flying a 2 hour flight. I unknowingly took off with the "ALTvSENSE" off on the VPX (which is the electric field wire), and my EarthX gave me everything it could. It was showing normal voltage until about an hour into the flight when it went from 14.1 to 11 volts in less that 30 seconds. I had zero time to troubleshoot. Ultimately my electrical system was out. No battery and no field (alternator) I lost all electrical... but nearly everything in my plane has battery back up. So the only thing I really lost was 2 radios, adsb, and transponder (and trim).
Long story short, after a complete power failure on a cross country... the cheap $5 compass was of completely no use to me.
I got the VPS figured out. I charged up the EarthX. I bought a MunkWorks generator. That should solve me future electrical issues before they happen.... knock on wood.
Actually the card does not have to be filled in for certification, it just has to be there. You may have to fly to another airport to find a compass rose.
When I fitted an EarthX battery I changed my alerting system so I was alerted immediately to abnormal (low or high) alternator output current and to loss of battery charging current.
Alerting should not depend only on battery or Main Bus voltage.
Ive flown down the section lines that are grid north and very close to true North and then subtract my declination and swing my magnetic compass to this. Gets me to within a deg or 2. Need a calm morning with no wind. I'll compare to my D180 and its close. Again within a couple of degs. Another check and verification against my gps. I still fly with paper maps.
The 99's have a program where they go around to various airports and painstakingly paint surveyed 70-80 ft compass roses, and re-paint when and if necessary. I don't know what they charge or how much, nor how they select, but the EAA chapter president at one of the little airports around here is a member of the 99's and at one time she mentioned that it was free. They've done several of the airports around here.
I was going to say - the 99’s do a great job on these, and I know of a few in our area. Unfortunately, one of them is literally half a wingspan away from a big metal hangar……
They're around...here's one in SoCal, at CMA... 
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Some time in the 60's a jet airliner that may have been a Douglas departed Montreal destination JFK Hours of darkness. middle of winter, severe clear.
Enroute failure of all electrical equipment. Cruised down to JFK and landed. Far too many of todays pilots are not capable of that. They did have a magnetic compass and a flashlight to read it.
Enroute failure of all electrical equipment. Cruised down to JFK and landed. Far too many of todays pilots are not capable of that. They did have a magnetic compass and a flashlight to read it.
rtlongdon
Well Known Member
KAWO, Arlington, Washington has a certified CR.
www.arlingtonwa.gov
About the Airport | Arlington, WA
Learn about the airport's facilities and services.
How would I know? The correction card is missing!
Seriously, in-panel compasses have a real problem due to their proximity to current carrying wires.
