Besides icing, once other limitation of the venturi power source
is how to sping the gyros up before takeoff. Seems to limit the
weather you would be able to launch into. I would not launch
into low IFR with venturi powered gyros.

Just my 2 cents.

Ronnie

"john hawkins" wrote in message
. net...
What ever happened to the god old venturi. Sure they could ice up Hasn't
anyone come up with a heated venturi (other than placing it the exhaust
streram)?
I got my rating in an old cessan that ran off venturi. two big fog horn
off the left side Bjut they worked.

"Jim Macklin" wrote in message
...
Most systems use a pump attached to the engine, which will
provide suction/pressure as long as the engine is turning.
Those pumps fail, their life is short and can be shorter if
abused during engine maintenance.
There are stand-by electric pumps and even engine manifold
sources are used in some installations. Many airplanes are
all electric [the new G1000's come to mind] and they have
redundant battery busses, generators and some also include
air driven gyros.


"Terence Wilson" wrote in message
...
| Hello,
|
| I was wondering how the primary vacuum is powered in a
single engined
| aircraft. If it was powered directly by the engine, a
engine failure
| would result in the immediate loss of attitude indicator
and heading
| indicator. So I guess most aircraft use an electrical pump
that can be
| driven by the alternator or battery, is this the case?
|
| Thanks in advance,
|
| Terence