Europa Aircraft Rotax 914, Installation Manual

Page: 36 / 47

Hold the spinner in place using adhesive tape or clamps then, with some form of reference pointer
positioned close to the spinner about 10 - 15cm (4"-6") back from the front, carefully
(with ignition
off - note that if the ignition leads have not yet been wired to switches the ignition will be live!)
rotate the propeller by hand to check for concentricity. Removal of a spark plug from each cylinder
will make turning the propeller easier.
Adjust the spinner as required to achieve concentricity then mark out and drill nine 4.8mm holes,
three equally spaced between each blade, through the spinner and the rear bulkhead flange.
Remove the spinner and install MS21047-3 anchor nuts onto the inside of the rear bulkhead’s flange
using TAPK 33 BS countersink rivets.
Measure accurately the distance from the rear bulkhead’s rear flange to the radial centre line for the
front bulkhead screws.
Mark a line around the spinner for the front screw radial centre line then mark off six equally spaced
centres around the circumference.
Drill through both the spinner and the front bulkhead flange with a 4.8mm drill at the six centres, then
install MS21047-3 anchor nuts to the bulkhead using TAPK 33 BS rivets.
The spinner is now ready for installation with screws; however, the propeller pitch must be set
beforehand.
Propeller pitch
The relationship between propeller pitch and aircraft performance is something which will vary
slightly between aircraft, so a certain amount of experimentation will be required to establish
individual aircraft performance figures.
Also, individual requirements, such as runway length available, will influence the final propeller
setting used.
It is suggested that you set the propeller to 21° pitch angle initially. The blade angle referred to is the
angle between the propeller’s rotational plane and the flat rear surface of the blade at the propeller
tip.
Make any subsequent pitch adjustments of no more than 1
o
at a time, assessing the difference in
flight performance each time.
Blade pitch adjustment
You may find your own method for adjusting the propeller blade pitch but the following method has
been found to work well.
Page 8 - 2
September 2001
Issue 4 Europa XS Rotax 914 Engine Manual