As almost everyone else said, it's the AN standard at 37 degrees. If you have
to flare tubing and there's not much to do, a standard 45 flare kit can be modified.
We had to do that on our plane for an STC installation... needed ONE end flared.
Rather than spending $100 on a tool to use once, or potentially more than that for an
aircraft shop to do it, we bought a $10 Home Depot special. Chucked it up in the
lathe at 37 degrees and cut a new flare taper... worked fairly well (aside from being
a bit of a POS flare tool to begin with).

YMMV
-Cory

Ernest Christley wrote:
: The most recent Sport Aviation has an article on make up hoses. The
: author states that 'you must use 37 degree fittings' and as is typical,
: gives no reason why. Is there a reason for this that involves the laws
: of nature, vs the "laws of the FAA"?

: --
: http://www.ernest.isa-geek.org/
: "Ignorance is mankinds normal state,
: alleviated by information and experience."
: Veeduber

--
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* The prime directive of Linux: *
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* (Just my 20 USm$) *
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