Can anyone provide his input about complety wrong erection (upside down or near) on start up ?
Does it evoke you specific failure from a technical / mechanical point of view ?
Peter !
This is exactly what I observed when rolling out from a steep turn (45°). It took tens of seconds to show that the wings were leveled.
Fortunately, when IMC, you don’t turn like that ;-)
On the bench, the AI was said to work properly (twice).
If they test it first on the bench, they can tell you if the instrument if faulty or not.
For some unexplained reason they can get intermittent issues. Also there is more than one item which can wear, apparently, so if the shop fixes one thing, something else can fail soon after. However I agree it is not rocket science; I think there are “human factors” issues in the repair shops…
I would still recommend getting it repaired/serviced by a competent shop, air driven gyros are not nuclear rocket science.
If they test it first on the bench, they can tell you if the instrument if faulty or not.
liftvectorup wrote:
get it repaired.
I will.
PS: but it would be of great help if seo familiar with those instruments, could tell if the problem likely comes from the AI itself, or the vacuum system (pump, regulator or tubing).
Having independent systems of alternator driven electronic systems and vacuum driven mechanical is good practice for failure scenario risk management. get it repaired.
So I am hopeless this way.
Not going to install a second alternator for that purpose :-)
I will struggle to have the vacuum one work (no reason we don’t reach that) and maybe find a neat AHRS based solution as a convenient add on.
Will keep you tuned !
Yes that’s correct. We have quite a lot of threads here, especially with posts by NCYankee describing the options.
However some battery backed instruments don’t have a big enough battery for this purpose.
Jacko wrote:
As I understand it, 1. requires that you must have a vacuum AI, as a backup to a (much more reliable) G1000. So it’s pretty unlikely that you will ever need the backup, and even less likely that it’ll choose that unfortunate moment to go tits-up.
My understanding is that you must have a backup with a separate power source. It doesn’t necessarily have to be a vacuum AI.
Jacko
You’re right.
Hence my interest in ADL200, which incorporate uncertified AHRS.
But, I must struggle to get the descent AI work at least properly. I can’t understand why I don’t manage to get such a basic instrument to work.
As for cash I would save, you had suggested some time ago, i keep it for Mrs PCV 
