Cessna 172 compass drift 30 deg in 10 mins
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roul its the wet compass, they call it a whisky compass because its filled with alcohol. Days gone passed when they leaked they only had whisky available to top them up with it. And when it leaked again you could smell it in the cockpit.
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Ah Well, Roulis....that depends on the country of origin....Scotland,= Whisky
Irish = Whiskey....AFAIK, no other country is allowed to use either name to describe a locally-produced Spirit.
I was once gifted a bottle of "Manx Spirit"....this crystal-clear fluid smelt just like Whisky and was the most flavoursome and beautifully smooth I have ever sipped (though I do lead a sheltered life
)
Originally, it was, indeed, called "Manx Whisky, distilled on the Isle of Man"
Scots had them take it off the label.
Irish = Whiskey....AFAIK, no other country is allowed to use either name to describe a locally-produced Spirit.
I was once gifted a bottle of "Manx Spirit"....this crystal-clear fluid smelt just like Whisky and was the most flavoursome and beautifully smooth I have ever sipped (though I do lead a sheltered life
)Originally, it was, indeed, called "Manx Whisky, distilled on the Isle of Man"
Scots had them take it off the label.
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172's can be fitted with an electrical HSI or a vaccum-driven DG in addition to the normal magnetic compass on the glareshield (obviously we're not talking about the G1000 variant).
If both the DG and the AI were acting funny as described I'd be looking for a vacuum leak beyond the manifold where the sender for the annunciators are since I presume if one of the VAC L or VAC R lights was lit we wouldn't be having this thread (at least in the SP there are 2 pumps and the manifold is just a 4 port assembly with a marble for lack of a better description that rolls back and forth between the two sides depending on which pump is operating higher at the time. This marble seals off one side in case of a vacuum pump failure and floats to kinda balance the system in normal 2 pump ops.)
But that's just me.
If both the DG and the AI were acting funny as described I'd be looking for a vacuum leak beyond the manifold where the sender for the annunciators are since I presume if one of the VAC L or VAC R lights was lit we wouldn't be having this thread (at least in the SP there are 2 pumps and the manifold is just a 4 port assembly with a marble for lack of a better description that rolls back and forth between the two sides depending on which pump is operating higher at the time. This marble seals off one side in case of a vacuum pump failure and floats to kinda balance the system in normal 2 pump ops.)
But that's just me.
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172's can be fitted with an electrical HSI or a vaccum-driven DG in addition to the normal magnetic compass on the glareshield (obviously we're not talking about the G1000 variant).
If both the DG and the AI were acting funny as described I'd be looking for a vacuum leak beyond the manifold where the sender for the annunciators are since I presume if one of the VAC L or VAC R lights was lit we wouldn't be having this thread (at least in the SP there are 2 pumps and the manifold is just a 4 port assembly with a marble for lack of a better description that rolls back and forth between the two sides depending on which pump is operating higher at the time. This marble seals off one side in case of a vacuum pump failure and floats to kinda balance the system in normal 2 pump ops.)
But that's just me.
If both the DG and the AI were acting funny as described I'd be looking for a vacuum leak beyond the manifold where the sender for the annunciators are since I presume if one of the VAC L or VAC R lights was lit we wouldn't be having this thread (at least in the SP there are 2 pumps and the manifold is just a 4 port assembly with a marble for lack of a better description that rolls back and forth between the two sides depending on which pump is operating higher at the time. This marble seals off one side in case of a vacuum pump failure and floats to kinda balance the system in normal 2 pump ops.)
But that's just me.
But that's just me.
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Been a while since I was in an N model, but don't they have some sort of light for the vac pump in addition to the dial gauge with the green pie slice? Memory's fuzzy but I thought it was just a single idiot light but honestly can't remember Most of my 172 time is in SP+ vintage.
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Been a while since I was in an N model, but don't they have some sort of light for the vac pump in addition to the dial gauge with the green pie slice? Memory's fuzzy but I thought it was just a single idiot light but honestly can't remember Most of my 172 time is in SP+ vintage.
