Hi!Paul
During my quest for improved fuel usage on my Jabiru 3300 I used to
blast around at generally 2,400 RPM with manifold pressure at approx. "
squared " (the general rule of thumb) at 24" at around 120 kts cruise
using about 6 Imp. Gallons per hour. I now have generally 5 Imp Gallons
per hour with 2,600RPM and manifold pressure of 20" but 110 kts cruise.
I can often improve on that but only by flying high. The colder ambient
temperatures allow a more efficient mix combination so you save fuel and
increase power
Hence Intercooler Technology.
Regards
Bob Harrison G-PTAG Europa MKI/Jabiru 3300
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Paul
McAllister
Subject: Europa-List: Fuel consumption - Cold day
<paul.mcallister@qia.net>
Hi all,
For some reason that is hard to explain, I took my airplane out flying
today
when it was really, really cold. I guess I hadn't had a "Europa fix"
for 3
weeks.
Anyhow, the OAT was -13 centigrade and I noticed that my fuel burn for
the
same power settings was significantly lower. At 28" @ 5000 I usually
run at
5 US gallons an hour.
Today it was 4.2 I was wondering what was the major contributing
factor.
For example, given that it was so cold, would the fuel density been
significantly different and I was still burning at the same pounds / per
hour rate, or was the dense air allowing the propeller / airfoil to be
that
much more efficient ?
Second question for those that are more familiar with Bing carburetors.
When I reduce power from around 28" to 23 " the EGT's spike. If I do it
too
quickly then the will hit the maximum allowable temperatures. Why is
this,
and is there an adjustment that I can make ?
Paul
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