Philip Sondericker wrote in message ...
in article fT27d.3595$mS1.2578@fed1read05, BTIZ at
wrote on 9/30/04 7:00 PM:

that would be one heck of a thermal ride... if it weren't for the rocks...
and "cough cough" the ash..

BT

I was thinking about this recently, and I was trying to determine exactly
what the effects would be on a small plane flying into an ash cloud. How
long would it take for the air filter to become completely clogged? And at
that point, assuming the plane had a carburetor, what would be the effect on
the engine? Would the plugs become fouled? Would they fire at all?

I'm a new pilot and relatively ignorant of engine operations, so I'm curious
to hear the answers.
Phillip
If you were unlucky enough, or foolish enough to fly into a volcanic
ash cloud, your engine would probably quit within minutes. That is if
the turbulence, or heat, or other potential trash like huge boulders
isn't in there to get you first!
The ash would quickly plug the air filter choking out the airflow. The
ash would most likely corrode your windscreen to an opaque as well as
take off paint from the leading edges. The engine may quit entirely or
just run weakly. there are reports of jet aircraft that sucked up ash
cloud and destroyed the engines from the abrasive pumice they
ingested. Many people to the east of St Helens had some expensive
repairs to their vehicles after all the ash had settled. It was a
couple of feet deep in many places as far away as 90-100 miles in the
Columbia Basin and Moses Lake area.
A friend of mine was crop dusting east of St Helens in the Palouse
area, a day after it exploded, when he said the ash entered the
cockpit of the spray plane and he couldn't even see the panel! Only
many thousands of hours of experience saved him from crashing.
Oddly enough I was flying around St Helens about two weeks before it
blew up. Got some pics of the snow melting around the top of the
mountain. After I saw the eruption, I had to shake my head that I
wasn't flying over it then!! I did a lot of crop dusting in the WA/OR
area and some of it was on the south slopes of St Helen.

Ol shy & Bashful