[Ipodder-user] T of the craft like so many slaps in the face; and others, with t

[Fluette <for...@al...>]

Be very smooth, especially towards the tips of the blades. Some
propeller tips have a speed of over 30,000 feet a minute, and any
roughness will produce a bad drift or resistance and lower the
efficiency. 9. MOUNTING.--Great care should be taken to see that the
propeller is mounted quite straight on its shaft. Test in the same way
as for straightness. If it is not straight, it is possibly due to some
of the propeller bolts being too slack or to others having been pulled
up too tightly. FLUTTER.--Propeller "flutter," or vibration, may be due
to faulty pitch angle, balance, camber, surface area, or to bad
mounting. It causes a condition sometimes mistaken for engine trouble,
and one which may easily lead to the collapse of the propeller. CARE OF
PROPELLERS.--The care of propellers is of the greatest importance, as
they become distorted very easily. 1. Do not store them in a very damp
or a very dry place. 2. Do not store them where the sun will shine upon
them. 3. Never leave them long in a horizontal position or leaning up
against a wall. 4. They should be hung on horizontal pegs, and the
position of the propellers should be vertical. If the points I have
impressed upon you in these notes are not attended to, you may be sure
of the following results: 1. Lack of efficiency, resulting in less
aeroplane speed and climb than would otherwise be the case. 2. Propeller
"flutter" and possible collapse. 3. A bad stress upon the propeller
shaft and its bearings. TRACTOR.--A propeller mounted in front of the
main surface. PUSHER.--A propeller mounted behind the main surface.
FOUR-BLADED PROPELLERS.--Four-bladed prope