This is an important question, because hauling a helicopter
on just any old trailer is a guaranteed way to destroy the airframe
tubing structure in short order. The frame of the helicopter is designed
to absorb flight loads for a long period of time. These loads have
to do with lift and torque and have nothing to do with bouncing over
the highway. Trailering the HELICYCLE therefore requires a correctly
sized spring, tire and axle set-up. In addition, the method of securing
the skids to the trailer deck and the proper support of the tail boom
is vital to preserving the airframes integrity while towing. The
answer to whether or not to trailer any two bladed helicopter with
the blades installed is simple: NO. Here's why. It is true that the
rotors can be supported to keep them from rotating and flapping up
and down. This however does not solve the most important problem.
Centrifugal force holds the blades rigid in flight and they are strong
in tension. At rest, the blades are prey to bending up and down (flapping)
and to bending laterally (in plane). When you drive over a pothole
or bump on one side of the trailer the ship will lurch in a lateral
plane. The mast could move 2 inches or more to one side and then the
other in a few milliseconds. The tip ends of the rotors cannot keep
up with this acceleration and three things can happen.
1. The blades will be forced to twist momentarily
(an unnatural condition.)
2. High bending loads will be placed on
the pitch spindles and pitch bearings. Since no centrifugal load
is present, these loads can easily exceed the bending loads imposed
during flight. This is not a good idea!
3. The lead/lag adjustments of the blades
are subject to being forced In the opposite direction to flight
loads, this could shift the adjustment, resulting in a dynamic
imbalance on the next run-up.
The HELICYCLE blades were designed for ease of removal and replacement
without any adjustment. It's only a 10-minute project. Across town
trips with the blades on may be okay, if great care is exercised to
avoid rough spots. Blades must be properly supported, of course. Now
that we've pointed out the pitfalls, what are the correct trailer
1. The HELICYCLE is very light, the trailer must be light and
lightly sprung. We use only two leafs in the springs.
2. the trailer must be tandem wheeled. A single wheel falls more
deeply into every rut and continually bounces the airframe.
3. We need to tow the ship tail first and this means a long tongue
on the trailer. The tongue must be rigid in both the horizontal
and vertical planes.
4. We would like to use the trailer for a take off and landing
pad, so the wheel base needs to be wider than normal and the top
of the tires should not be a skid hooking hazard.
5. The tail boom of the ship has to be shock supported vertically,
but free to move laterally.
6. The skids need to be lashed to the deck at the proper position
and the clamps constructed so that they may be installed and removed
7. Lastly, a winch and ramp system is needed just in case the
ship can't be flown on the trailer at a particular location.
A good engineer/designer can probably come up with a trailer that
meets all these specifications on the first try, however it's quite
a tall order, unless you're very familiar with the problems.
TO THIS END, WE ARE PROVIDING BLUEPRINTS & CONSTRUCTION DETAILS
FOR A WELL-TESTED HELICYCLE TRAILER YOU CAN BUILD YOURSELF. IF YOU
DON'T WIRE-FEED WELD, YOU CAN PRE-CUT THE SQUARE TUBES FOR THE FRAME
AND HAVE THEM WELDED AT A LOCAL SHOP. REFER TO:
THE FACTORY, FOR ORDERING INSTRUCTIONS.
Eagle RnD 2512 Caldwell Blvd. Nampa, Idaho USA 208-461-2567 Fax 208-454-3752