Hello, Andrew,
Welcome! (another fellow builder in Ohio, cool).
Re IFR and the 914: If you go for vacuum gyros, the only pad for
either a CS prop governor or a B&C secondary alternator is taken up.
Rotax has a belt-driven alternator option, but the XS cowling
interferes. If you opt for electric gyros, you lose redundancy in the
event of electric failure. But secondary alternator and batt solves
that. For a controllable-pitch prop, there are electrics (e.g.,
Airmaster) and a newly announced mechanically controlled one
(Proplink).
For pitot heat, you'll need both the much extra alternator juice and a
way of mounting it so it doesn't cook the fiberglass. The airframe
cannot stand a lightning strike, and how the laminar flow wings and
all-flying tail will react to even small am'ts of rime is unknown. So
between these problems and opting out of pitot heat means you're
committing to no "Ohio-style" IFR in cloud above the freezing level
and any possibility at all of TRWs whether embedded or in bad haze.
For strobes (and night cert), it's wise to verify they meet the
minimum intensity requirements of FAR 23.1402 (400 candles).
All of the above can pose a problem for night and IFR certification,
since it cannot be known in advance what FAA will insist upon.
Redundant power sources for gyros, and pitot heat, are not req'd by
FAR 23, but I hear stories that some FAA offices will so insist for
IFR. Part 91 mandates an "approved" strobe system, and Part 23 does
require lightning protection for IFR. Although Part 23 does not apply
to homebuilts, "airworthiness" is what the inspector deems it to be,
and if Part 23 or what Cessna etc. do sounds good for a guideline,
then.... By the time you're done, the FAA may have realized its dream
of getting out of the homebuilt business, going to private-sector
Designated Airworthiness Rep's. These folks might be more finicky,
fearing they won't have the liability immunity the FAA enjoys. Except
for the lightning protection that you can't do anything about, these
are still safety implications anyway that you decide upon yourself,
FAA notwithstanding.
[BTW I will attempt IFR cert, but I wanted the gyros and dual
electrical anyway].
Regards,
Fred Fillinger, A063, N3EU
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