Re: Fwd: low ceiling high duration

From: Mark <f1diddler_at_yahoo.com>
Date: Mon, 01 Dec 2008 22:31:10 -0000

--- In Indoor_Construction_at_yahoogroups.com, "and4metoo" <stankos@...>
wrote:
>
>Does anyone have an opinion as to what few degrees downward thrust
> might do for you in climb phase? Will it hurt you when your cruise
> phase is over?
> At Sci Oly last year some students had their planes flying ever so
>flat and climbing ever so slow. Prop seemed to be slow so I think
> prop pitch was on the high side.>>
>
> Pete


Most of us accept downthrust as a necessary evil, but try to minimize
how much is needed. But at some point, better stability results in
more time. Sometimes downthrust is accomplished with only stick bow
from rubber tension which is highest at launch (That's where down is
the most needed.)

For low ceiling work, if you are backing off turns, you may be
launching at relatively low torques, so you could experiment with less
or no downthrust there. (But I have always gone back to using
downthrust, after such experiments.) A few indoorists say they do just
fine without any downthrust.


> flat and climbing ever so slow. Prop seemed to be slow so I think
> prop pitch was on the high side.>>

Prop pitch is another subject, not usually related to downthrust, but
sometimes higher RPM from lower pitch can accomplish stability too.
Mark F1diddler
Received on Mon Dec 01 2008 - 14:31:14 CET