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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.
