Backup vacuum systems

I have Precise Flight. I think a recent install bypasses most/all ADs.

Clearly a backup pump or electric AI provides more at a comparable cost.

Whatever you do, have an idiot light that tells you something failed.
Precise Flight provides that and it may be as useful as the actual
backup if you otherwise don't have a light.

ktbr wrote:
wrote:

Anyone have any experience with or comments about the manifold pressure
based standby vacuum system vs a separate electrical driven vacuum
pump? Other than the price difference. I want to install a backup and
am interested in getting some info.

Maule Driver wrote:

I have Precise Flight. I think a recent install bypasses most/all ADs.

Clearly a backup pump or electric AI provides more at a comparable cost.

Whatever you do, have an idiot light that tells you something failed.
Precise Flight provides that and it may be as useful as the actual
backup if you otherwise don't have a light.


I also have a Precise Flight, installed in 1996. Mine was an SVS-III
which is the subject of the AD. Turns out if you have the later style
valve (sold since around 1992), it is just a paper work change...new AFM
supplement and a copy of the AMOC letter...to change it to an SVS-V in
order to terminate the AD. All the paperwork is available from the
website, so if you do the paperwork updates and show it to your A&P, it
should cost you nothing more than a box of donuts or six pack of beer.