Pietenpol-List: Engine thrustline offset
Posted: Fri Oct 23, 1998 12:48 pm
Original Posted By: Michael Brusilow
Usually the measurment of "an inch" is taken at the prop end of the crankfrom center. I built my mount square and shimmed with washers at the mountattach point.Flies great. I also added 1/2" offset at the front edge of the verticalfin.Steve e.-----Original Message-----Greg CardinalSent: Friday, October 23, 1998 12:22 PMSubject: Pietenpol-List: Engine thrustline offsetI'm starting to think about the A-65 motor mount and would like tohear from builders who have completed and flown their planes.Did you build in any offset to the thrustline?Plans show some downward thrust but no offset to the right.I know some people build it in but I don't know how much.One experienced builder says "Down 1 inch and to the right 1 inch."That's fine until you think about the angle of offset.If shims are used at the motor mount to engine case connection toachieve 1" the angle is greater than if you used a pivot point fartheraft.So, the questions are:1. How much offset did you build in?2. How did you achieve your offset?3. How does it fly?Thanks,Greg Cardinal in Minneapolis________________________________________________________________________________
Usually the measurment of "an inch" is taken at the prop end of the crankfrom center. I built my mount square and shimmed with washers at the mountattach point.Flies great. I also added 1/2" offset at the front edge of the verticalfin.Steve e.-----Original Message-----Greg CardinalSent: Friday, October 23, 1998 12:22 PMSubject: Pietenpol-List: Engine thrustline offsetI'm starting to think about the A-65 motor mount and would like tohear from builders who have completed and flown their planes.Did you build in any offset to the thrustline?Plans show some downward thrust but no offset to the right.I know some people build it in but I don't know how much.One experienced builder says "Down 1 inch and to the right 1 inch."That's fine until you think about the angle of offset.If shims are used at the motor mount to engine case connection toachieve 1" the angle is greater than if you used a pivot point fartheraft.So, the questions are:1. How much offset did you build in?2. How did you achieve your offset?3. How does it fly?Thanks,Greg Cardinal in Minneapolis________________________________________________________________________________