On Wed, 24 Dec 2003 23:56:38 -0600, RR Urban wrote:


I can't address what Lancair is doing, but....
my early RV-3 has UNFILTERED RAM AIR.

However, when carb heat is applied....
the alternate air path is through a filter
setup under the cowl.

All is still going well after 700+ hours.
Oil consumption is a quart in 15-20 hours.

To date, bugs have not been a problem.
There is an inlet screen and I'd guess the
occasional small bug just gets sliced, diced
and digested uneventfully. A swarm of locusts
could be a different story. g

The only thing I have discovered so far is that the
ram air path, as originally implemented, affected fuel
distribution to the cylinders somewhat negatively.
The cure is vane(s) properly positioned in the air
path or just use Van's later style intake air setup.
[I have a MM-1 buddy with a similar ram air setup
with the same damn fuel distribution issue.]


Barnyard BOb -- over 50 years of successful flight


that is most curious bob. my aircraft has a brackett foam airfilter
(replaced annually) on the air inlet and none on the carby heat. the
reasoning is that carby heat is only applied when well off the ground
and the risk of contamination is small.

the problem is not bugs imho the problem is grains of sand.

you sure the builder didnt rig it up backwards?
Stealth Pilot