Bob and all,
>As the others have said, additional power is available due to a cooler, denser
charge of air. But there is another reason to add an intercooler. That hot,
compressed volume of air that comes out of the turbocharger is prone to cause
detonation. By cooling the air, you greatly reduce the chances for detonation
which is always a problem with turbocharged or supercharged engines. This is
the reason I chose to add the intercooler.
>
>
That is also the reason we went the intercooler way.
>I have been told that by adding an intercooler, the 5 minute limit on max power
is no longer necessary. That limit was imposed to ensure the engine never went
into detonation. With the intercooler, one can use full power continuously.
Please understand that this is hearsay information and I have not proven or
tested it. Perhaps others more experienced in the area can comment.
>
>
>
I would be wary about that one, except if it came direct from the Rotax
development team.
Remember that with cooler charge temperatures, the engine delivers more
power than usual. If you use the same MP than non-intercooled, you are
asking more from your engine, not to mention higher and longer 39'
operation than recommended.
Note that Lycoming advises to use lower MP settings when intercooled for
that reasons.
The engine is less prone to detonation, but this does not justify asking
more than intended from it.
Besides, it is indeed a draggy airframe, that necessitates more than 5
minute takeoff power !
We chose to use the normal power settings with our intercooler, but I
retard the throttle to 100% as soon as I'm airborne. Our field has a
2000 ft grass strip, and we have ample room to operate at full weight.
Regards,
Gilles Thesee
Grenoble, France
http://contrails.free.fr
|