Jonathan, I suspect you are dealing with two distinct effects here. The
tendency to roll to the right suggests to me that you have slightly
different effective angles of attack on the two wings, either because of
how the wings were constructed or because of how they were attached to
the fuselage. This seems to be very common and a small piece of
triangular section wood, length adjusted for effect, under (in your case
) the port aileron will correct it. As previously stated the engine
offset is there to correct the tendency for the clockwise spiral
propwash around the fuselage impinging on the left side of the fin and
tending to produce a left turn. This effect is most noticeable on take
off (and probably also in monos) when at max power and lowish speed with
limited rudder authority, when a significant amount of Right rudder is
needed to keep in a straight line. It is also noticeable in a full power
lowish speed climb. I believe that the amount of offset is designed to
allow hands off balanced straight flight at typical cruise speeds/power,
whilst also helping to maintain control authority on take off. Regards,
David Joyce,GXSDJ
On 2017-01-14 22:41, jonathanmilbank wrote:
>
> I'm converting my Classic to XS firewall forward and the instructions for
> mounting
the engine call for the 4 washers on each lord mount to be arranged so that
the engine is angled 1.5 degrees to the right.
>
> The Classic build manual didn't give this stipulation and so mine was pointing
straight ahead. What effect will there likely be when I start flying in the
new configuration. Up until now there has been a tendency for the aircraft to
roll gently to the right in the cruise.
>
> Will angling the engine to the right make the right roll tendency better or
> worse?
Please give me the aerodynamic logic for this 1.5 degree offset.
>
> Thanks.
> Jonathan
> Of how they are mounted on the fuselage. This is very common and can be
> readily
corrected with a small trangular section of wood stuck under the (in your case)
port aileron
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=465078#465078 [1]
>
Links:
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[1] http://forums.matronics.com/viewtopic.php?p=465078#465078
[2] http://www.matronics.com/Navigator?Europa-List
[3] http://forums.matronics.com
[4] http://wiki.matronics.com
[5] http://www.matronics.com/contribution
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