And you STILL want to remove that vacuum (or electric) horizon??

Yes.

Vaccuum horizons also fail (or the vaccuum pumps do). I can say that my club has had several failures of vaccuum horizons but so far no failure of our G1000 EADI. (Well, we did have a AHRS realign once which could have been unpleasant in IMC.)

In the clip it is very obvious that the EADI has failed. A failed vaccum horizon is necessarily that obvious. Particularly not if the reason is lack of vaccuum.

I think we all agree you need both one electric and one vacuum; anything else is called “suboptimal” setup

Never meant to remove it. It’s better not to rely on one source of energy alone. And vacuum is easiest to obtain, if no electricity is to be involved…

Yes, vacuum fails, but the roots of failures for the vacuum system are so different and occur in another time span than compared with failures of an electrically driven system, that it’s hard to have to face a moment where all systems fail at the same time.

I think we all agree you need both one electric and one vacuum

I disagree. Two software- and power-independent electronic horizons perhaps, but backing a reliable electronic horizon or PFD up with an antiquated mechanical gyro which is short-lived and prone to insidious failure seems a bit like towing a horse behind your car in case the engine conks out.

On second thoughts, albeit not much of a threat until today, the horse and gyro should survive a nuclear electro-magnetic pulse…

Jacko wrote:

Two software- and power-independent electronic horizons perhaps,

Don’t both rely on internal GPS for “attitude aiding”?

Anyway, I was talking about the required backup for 2nd AI to keeping flying accurately under IFR (in Airways or Radar assigned heading & altitudes) until destination and shoot ILS200 with 1km visibility, just like nothing happened to the 1st AI, as far as surviving in IMC until you reach VMC, the AI is not mandatory at all, an independent turn coordinator is more than enough

For flying in uncontrolled clouds, some skilled pilots can keep their calm and wing level using simple panel mounted PDA moving map or VHF “non-gyro” guidance but I am bloody sure most of them will spiral down in busy TMA after 5th vector or altitude step…

Obviously, one can’t lose VMC, AHRS, GPS, COM, VACCUM at the same time? they should be cursed

I did with my replacement of the Stec FD with a G500TXi and a G5 that is independently backed up with a battery.

Ibra wrote:

Don’t both rely on internal GPS for “attitude aiding”?

Purely gyroscopic electric ones don’t. Such as the RCA26EK or similar. However, they are also in the $2’300 range while vaccum gyros are about half that.

I’d not be worried big time for EMP as if we get to that scenario then GA flying will have stopped a while before. However, GPS degradation may be a very valid concern pretty darn quickly, which may well cause most of our gadgets to degrade or malfunction. However, in all these scenarios I guess a stop of GA activity is very likely to happen.

Personally I kept the vaccum pump going. And I have the Aspen, Vaccum and the Dynon D1 as the third source.

Ibra wrote:

Don’t both rely on internal GPS for “attitude aiding”?

@Ibra they dont’t – actually attitude sensors should be just solid state gyros, not GPS, unless it is for a homebuilt! ;)