Relocating the compass as a safety measure

[Kent Wien]

I’ve managed to hit my head on the compass mounted above and in the center of the airplane a few times already. This doesn’t seem ideally located in the case of an accident and it takes away a slight bit of the visibility of the otherwise excellent view in the Husky.

Has anyone had any success with a panel mounted compass? I know interference is a big reason compasses are mounted where they are, but perhaps it’s possible to find a better spot in the Husky.

 

[Snowbirdxx]

Kent, you can easy move it under the panel. No need to see it. If you move it, not seeing it is better than seeing it with wrong indications. I tried to demagnetise the airframe a couple of times, no luck.
Wear a helmet or put a foam cover over the compass.

 

[Bjames777]

Kent, you can easy move it under the panel. No need to see it. If you move it, not seeing it is better than seeing it with wrong indications. I tried to demagnetise the airframe a couple of times, no luck.
Wear a helmet or put a foam cover over the compass.

I am a bit confused on the “No need to see it”. FAR 91.205 tells us otherwise here in the USA.

 

[tbienz]

I didn't look at it real carefully, but does 91.205 actually say the compass must be in plain view without contorting one's head? It seems to just suggest the plane should have a compass.

 

[Kent Wien]

The MD-80 has it on the back wall behind the copilot. Of course, they give you a finger-sized rear-view mirror to look at the compass if you need it.

But I digress.

 

[Larson]

Kent, your hanging in too tight- don’t lean forward, sit back and enjoy the ride!
Ok, on a serious note- I did see a compass mounted in the panel. Personally, I have started wearing a helmet more now- not that there is much to protect- but thought it wiser with all the steel tubes (and compass) around ones head.

 

[jliltd]

If you put in a G5 with a GMU 11 remote magnetometer you can ditch the whiskey compass. The FARs simply state you must have a magnetic heading reference which the GMU 11 with G5 provides. There is no stipulation that the heading reference must be a traditional mechanical bubble type compass.

 

[Kent Wien]

If you put in a G5 with a GMU 11 remote magnetometer you can ditch the whiskey compass. The FARs simply state you must have a magnetic heading reference which the GMU 11 with G5 provides. There is no stipulation that the heading reference must be a traditional mechanical bubble type compass.

That’s it! Thank you!!

 

[DogLip]

If you put in a G5 with a GMU 11 remote magnetometer you can ditch the whiskey compass. The FARs simply state you must have a magnetic heading reference which the GMU 11 with G5 provides. There is no stipulation that the heading reference must be a traditional mechanical bubble type compass.

Have you installed the GMU 11? If so, how did you get the wires from the tip to the wing root. Did you use a conduit of some sort?

-DogLip

 

[Snowbirdxx]

Used plastic tubing normally used to run electric cables in the basement. 20 mm diameter. They are 8 ft long, used two stuck together with safety tape. Put a round plug in the frontend, pushed the tube though the D box, removed plug inserted cable. If your d pax is plugged by the landing light, do the same from the wingtip just behind the spar. No big deal.

 

[MTV]

If you put in a G5 with a GMU 11 remote magnetometer you can ditch the whiskey compass. The FARs simply state you must have a magnetic heading reference which the GMU 11 with G5 provides. There is no stipulation that the heading reference must be a traditional mechanical bubble type compass.

And, how does that all work when the electrons stop flowing? Electro magnetic compass doesn't replace a whiskey compass. Here's the definition of "magnetic compass" from the FAA: "Definition: Magnetic Compass, Contains ferrous-magnets which interact with the earth's magnetic field and aligns itself to the direction of the local magnetic field. Stand-Alone, Means that the compass is in no way connected to any other directional devices and/or electrical power source, in the aircraft."

Good luck getting an electro magnetic compass approved as a stand alone.

MTV

 

[JACK]

The last airplane I flew for a 135 outfit (Citation XLS) had no whiskey compass. Certified that way.

 

[jkalus]

And, how does that all work when the electrons stop flowing? Electro magnetic compass doesn't replace a whiskey compass. Here's the definition of "magnetic compass" from the FAA: "Definition: Magnetic Compass, Contains ferrous-magnets which interact with the earth's magnetic field and aligns itself to the direction of the local magnetic field. Stand-Alone, Means that the compass is in no way connected to any other directional devices and/or electrical power source, in the aircraft."

Good luck getting an electro magnetic compass approved as a stand alone.

MTV

I can’t really argue with that but the Cessna Citation XL had a wet compass, the XLS did not. There must be a level of redundancy that permits its removal. Possibly the battery backup on the standby.

 

[Kent Wien]

Thanks Mike.

That’s pretty clear. Hard to argue with that description.

Kent

 

[jliltd]

And, how does that all work when the electrons stop flowing? Electro magnetic compass doesn't replace a whiskey compass. Here's the definition of "magnetic compass" from the FAA: "Definition: Magnetic Compass, Contains ferrous-magnets which interact with the earth's magnetic field and aligns itself to the direction of the local magnetic field. Stand-Alone, Means that the compass is in no way connected to any other directional devices and/or electrical power source, in the aircraft."

Good luck getting an electro magnetic compass approved as a stand alone.

MTV

You must be talking to the wrong FSDO guys.

Your compass quote is a term definition. Not a requirement statement but a good definition nonetheless. There are many defined terms.

The crux is the FAR does not specify a "compass". Only a "magnetic direction indicator". I also cannot find "Stand-Alone" but I do find "Independent". I will assume both are defined.

See CFR Title 14 part 91.205 (3).

Also see a 2011 Advisory Circular (not regulatory, only advisory) AC 23.1311-1C. Paragraphs 8.7 and 8.8.1 clarify this.

So either a compass, as defined, or any other approved magnetic direction indicator, whether running on whiskey or electric juice, meets the requirements of CFR Tiltle 14 Part 91.205 (3).

The philosophical and duly practical point as to whether the electrons keep tronning or not is well taken and is a personal choice. I for one like having a whiskey compass in addition to a remote magnetometer. However, many times the FAA takes the stance that if a new item is a primary replacement the original item needs to be removed or disabled via inop. Which never made any sense to me. Back on track. With regard to airworthiness, any type of approved magnetic direction indicator by itself complies with Part 91.205(3).

Kent, if you feel more comfortable keeping a traditional compass yet want to relocate it's position I would go for an SIRS Navigator pedestal mount compass and place it on the glareshield. But if you do add a G5 definitely install the GMU 11 and GAD 13 options. It is super nice having slaved heading system and air data calculations like TAS and a wind vector showing your winds on the display along with density altitude and OAT.

Jim

 

[belloypilot]

You must be talking to the wrong FSDO guys.

Your compass quote is a term definition. Not a requirement statement but a good definition nonetheless. There are many defined terms.

The crux is the FAR does not specify a "compass". Only a "magnetic direction indicator". I also cannot find "Stand-Alone" but I do find "Independent". I will assume both are defined.

See CFR Title 14 part 91.205 (3).

Also see a 2011 Advisory Circular (not regulatory, only advisory) AC 23.1311-1C. Paragraphs 8.7 and 8.8.1 clarify this.

So either a compass, as defined, or any other approved magnetic direction indicator, whether running on whiskey or electric juice, meets the requirements of CFR Tiltle 14 Part 91.205 (3).

The philosophical and duly practical point as to whether the electrons keep tronning or not is well taken and is a personal choice. I for one like having a whiskey compass in addition to a remote magnetometer. However, many times the FAA takes the stance that if a new item is a primary replacement the original item needs to be removed or disabled via inop. Which never made any sense to me. Back on track. With regard to airworthiness, any type of approved magnetic direction indicator by itself complies with Part 91.205(3).

Kent, if you feel more comfortable keeping a traditional compass yet want to relocate it's position I would go for an SIRS Navigator pedestal mount compass and place it on the glareshield. But if you do add a G5 definitely install the GMU 11 and GAD 13 options. It is super nice having slaved heading system and air data calculations like TAS and a wind vector showing your winds on the display along with density altitude and OAT.

Jim

I finally got around to looking up the Canadian regs regarding compass requirements.

https://laws-lois.justice.gc.ca/eng/regulations/sor-96-433/page-116.html#h-996604

605.14 (d). Short story, it has to be a magnetic direction indicator that operates independent of the aircraft electrical generating system. Does something with a 4 hour battery backup meet that requirement? Probably not but I haven’t ask the question to any of our Transport Canada folks so I don’t really know.

 

[Kent Wien]

Thanks to the great advice above, I’m going with the Sirs Navigator mounted on the glareshield. Will post the results here.

 

[brianP]

I have had compass issues also so I bought the Sirs navigator its a nice compass but now I own 2 compasses that don't work. Willl try degousing next but I have low confidence based on what I've read hear

 

[Kent Wien]

Oh no. Thanks. Fingers crossed.

 

[jkalus]

Doesn’t the compass mount have pointed square corners? Why not just radius the mount so that it doesn’t dimple your skull?