Similar types of planes (check the position of the wings, stabilizers, motor and camera):
Bananahobby.com
Hobbyexpress.com
site.nitroplanes.com
mikeysrc.com/MRC_FPV_Camera_Plane.pdf
sailplanes.flytodream.com
Example of real powered glider design, sysmcape.com
Avinc.com (look for Wasp III, used by US Marines)
Let’s make the first draft of the plane shape:
The fuselage is going to be as thin as possible, gaining thickness in the front part, where the pilot would be in a large scale glider but instead this place is going to hold the battery and other electronic components such as the PCB, receiver and the camera. The front part must be shaped as much aerodynamically friendly as possible. This wider part is also where the wings will be attached to the body.
Fuselage width must be sized depending on the battery+PCB+receiver+camera size.
The wings will be placed in a medium height (relative to the fuselage bottom). Each wing will have just one control surface, the aileron, placed on the exterior part to create more momentum and a winglet in case further study proves they increase the aerodynamic efficiency. Ailerons can work as the missing flaps and no airbrakes/spoilers are needed for this plane due to low flight speeds.
Gyroscopes for plane stabilization are another option to be yet determined.
No dihedral or sweep angle is considered necessary at first, improving the manufacturing process.
Further study of spiral mode and stall when climbing or turning.
In the empennage, a high horizontal stabilizer plus elevator configuration will be chosen, to avoid turbulence interference created by the wings.
As in most planes, the vertical stabilizer will be just one vertical part with the rudder at the rear.
No landing gear is needed as it will take-off with the hand-launch technique, but a landing device might be useful to decrease the impact force.
The motor position is more variable in the design. One possibility is to place it at the very front of the fuselage, making possible a direct spool connection. One first idea is to make it bendable with the air flow to reduce drag in case of unpowered flight and reduce the chance of damage when touching the ground.
Another option to avoid motor damage and don’t interfere with the camera is to place the motor on the top of the middle fuselage section. In that case, the empennage configuration must be changed to a low stabilizer and the wings should be moved upper.
The third option is to place the motor at fuselage-height but only with a twin boom configuration, as in this design:
Wikipedia.com (twin-boom aircraft)
The fourth option is to place is at the very end of the empennage, as in the MQ-9 Reaper UAV:
Wikipedia.com (MQ-9 Reaper)
The last valid option is to use 2 motors, each one mounted on the wing (better below it), so they don’t interfere with the line on sight and they increase the performance of the aircraft. But for a powered glider, one motor is good enough.
Several options are taken into account with a CAD model (using Autodesk Inventor Professional 2011 Free Student Version):
Placing motor at the front and changing wing configuration:
Changing motor to the back of the plane to avoid camera obstruction:
Changing motor to the center to increase stability and avoid the camera, which will be placed at the very front, like from the pilot’s view.
Where the motor is placed affects the wings and elevator too, because they must not interfere with each other in stabilized flight.
If the engine is at top height, elevator must be at the bottom so the turbulence from the air passing through the engine doesn’t affect it.
The wings turbulence mustn’t affect it either, so wings will be placed at top height of the fuselage, just before the engine so they don’t interfere.
(Fuselage is yet to be shaped in order to carry the payload while creating low drag)
With the shape almost fixed, the size is the next thing to be determined.
An important parameter to be taking into account is the transportation of the airplane. It must be designed to fit in an average car. It can have less wingspan and length than that of a car’s interior or it can be disassembled into several pieces (dividing the fuselage in two parts or cut out fuselage and wings).
These are the most restrictive dimensions, restricted by the manufacturing process, not by transportation means.
Dimensions in mm
To fit in a car it should be around 2.5 meters wide and around 1 meter long. This is the most compact possible way it could fit, but still doesn’t.
Either it is reduced or dismantled before travel.
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