View Single Post
  #70  
Old November 15th 08, 02:44 PM posted to rec.aviation.homebuilt
stol
external usenet poster
 
Posts: 161
Default effect of changed thrust line.

On Nov 14, 2:59*pm, wrote:
On Fri, 14 Nov 2008 13:24:47 -0600, cavelamb himself



Lowering the thrust line to below the center of aerodynamic drag would

cause nose up - OK I get that. Now where is the center of drag on a
peg? and it will DEFINETLY change with flying attitude - ie with the
flaps on, or the slats extended.

I guess what it boils down to is it will not be a HUGE effect.
On a 28" long engine, 3 degrees is roughly 1.5" offset, so 1/4" is
roughly 1/2 degree. One 1/8" washer at the firewall and one at the
engine rubber on both sides will make 1/2 degree change if I need to
do a bit od "fine" tuning.


Spec for the O200 mount is 1.5 degrees down IIRC,amounting to .75"
offset - guess I'll put in about .875 and see what happens


This is all good till you consider that cowling you spent days
trimming to get it to fit perfectly will now be junk.