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Can one have an IFR aircraft without a vac pump but with only one alternator?

Here I have the following text I got from a specialist in the USA, around 2009

It seems that a second battery, of a certain minimum size, is the only possible solution. What is the current FAA and EASA position on this?

Administrator
Shoreham EGKA, United Kingdom

EASA position on this?

I see no problem here. Our aircraft have no vacuum system at all. The standby gyros have their own battery which is independent from the rest of the electric system (apart from a one-way connection that keeps it charged), and this is all what’s needed.

EDDS - Stuttgart

I see no problem here. Our aircraft have no vacuum system at all. The standby gyros have their own battery which is independent from the rest of the electric system (apart from a one-way connection that keeps it charged), and this is all what’s needed.

Same in the Meridian. No vacuum for instruments (actually is vacuum for boots) and standby has battery and is cap checked each annual.

EGTK Oxford

The same is true for Aspen nowadays. They have certified the battery solution mentioned in your 2009 text.

There a several new electronic attitude indicators which are approved to be used as “backup” instrument for other glass products.

JP-Avionics
EHMZ

Would I be correct that the only replacements for the KI256 vac AI (for the KFC225 autopilot) are still

  • G500+GAD43
  • EFD1000+EA100

I spoke to some avionics firms whose products output “uncertified” pitch and roll over ARINC429 about doing a converter to the KI256’s “LVDT” pickoff coil emulation (which is prob99 what the GAD43/EA100 boxes do) but the reply was that there is no market for it. OTOH there are many thousands of King autopilots which must have the KI256 (or the version of it that doesn’t have the flight director).

Castleberry do an electric “copy” of the KI256 but while it is TSOd it has no STCs, and one line of argument is that it cannot be installed to drive the AP unless there is an STC for that exact application; no field approval route exists.

Administrator
Shoreham EGKA, United Kingdom

The KI300 is coming soon…

LFPE

too expensive

RC Allen with backup battery would be much cheaper?

I got rid of all Vacuum stuff in the Commander. However .. as my 114TC is equipped with TKS I have a dual alternator. My aspens (PFD and MFD) as well as the RC Allen all have a separate battery backup.

The DA-40 G1000 has only one alternator and no vacuum, and the PA-32/ Piper 32’s w/ Avidyne is the same. They both have backup AI with their own battery. In case of the DA-40, it is a simple pack of standard dry non-rechargeable 1,5V elements (as I recall) and in the PA-32 the backup AI battery is kept charged from the alternator (I think). Both types are, of course, IFR certified.

huv
EKRK, Denmark

How much would it be for the simplest installed IFR aspen?

LFPE

No Vac system and a Midcontinent SAM is the EASA certified back up for the G500 STC on the DR400.

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