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Do i need a compass?

i think that wording applied before gps was ever invented. if you know [and you should] the magnetic deviation where you are flying...well, there you go.
 
i think that wording applied before gps was ever invented. if you know [and you should] the magnetic deviation where you are flying...well, there you go.
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...
 
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.
 
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.
my fsdo guy would simply not accept it; he demanded a compass. Showed him the wording and he said "yes, mag dir indicator means compass; no compass, no awc." I just installed a cheap one, as it wasn't worth the consequences of arguing with him.
 
my fsdo guy would simply not accept it; he demanded a compass. Showed him the wording and he said "yes, mag dir indicator means compass; no compass, no awc." I just installed a cheap one, as it wasn't worth the consequences of arguing with him.
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).
 
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".
 
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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.
 
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."
 
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.
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.
 
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".
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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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).
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 :)
 
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