Salut Gilles,
My question regarding cooling on the ground is because all Rotax equipped
Europas
are known to overheat very quickly on the ground. I know some guys who say
they do not overheat, but I have often observed them taxiing very fast to the
holding point to be sure they are aloft before reaching the boiling point. Again
the design of the Europa cowl is not optimal but cooling in flight is very
effective. On the ground however it does not work properly. I am now convinced
that the main cause for this poor cooling on the ground is the propeller. Most
Europas are fitted with Warp Drive props or Airmaster hub Warp Drive blades
combination. Those blades are narrow at the root and not very much twisted.
Therefore
they do not provide a lot of air flow where the air inlets are located.
On the other hand, most MCR are using the MT prop whose design is just the
opposite: very wide blades at the root and a lot of twist which is a lot more
effective ventilator.
My own fix for the Europa cowling is a variable air scoop, below the existing
inlet,
ahead of the radiator. Theoretically it is very bad, but it works! It works
because this additional inlet is located farther from the propeller axis,
therefore receiving more air flow. Sure this adds a lot of drag, but who cares
about drag during taxi and run-up? The scoop is positioned back to neutral
just before take off and can be closed to blank the radiators at cruise and
descent
at cold temperatures.
Remi Guerner
Europa F-PGKL
No problem on the ground.
During first run ups we ran the engine as long as 30 minutes continuous
with several full power runs then fast idle periods.
I did not take special measurements on the ground, only monitoring CHT
during warm up, taxi, etc...The aircraft was test flown from - 14C to +
37C OAT.
I can do take the measurements you require when flying with a helpful
passenger, but since we're in autumn, you'll have to wait until summer
for hot day conditions.
Best regards,
Gilles
http://contrails.free.fr
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