Day Chahroudi

Version:1.0StartHTML:0000000176EndHTML:0000008728S tartFragment:0000003139EndFragment:0000008692Sourc eURL:file://localhost/Users/daychahroudi/Desktop/Model%20Jet.docVERY FAST AEROBATIC MODEL JET
[IMG]file://localhost/Users/daychahroudi/Library/Caches/TemporaryItems/msoclip1/01/clip_image002.jpg[/IMG]


Speeds of 600 mph should be possible, while maintaining verylow drag and high maneuverability at all speeds and g-loads because:

Wetted area and frontal area are absolutely minimal
Wings and tail are small, swept, and high aspect ratio, withsupercritical airfoils
Low wing/body shock and interference drag
Turbojet exhaust blends smoothly with airflow
Turbojet fed unobstructed ram air pressure
Light weight from simple, small shape

The long tail booms allow large deflections of the full spanflaperons -- for low stall speed in spite of a high wing loading for les****g. Flap deflections are largeduring takeoff and landing and small during high-g maneuvering. The wing’s high aspect ratio reducesinduced drag at high g, but stalls more easily and violently than a deltawing. Preferably, onboard sensorsof airspeed, angle of attack, and g-load will control in real time the flapdeflections for maximum L/D, and also control the elevators to prevent stall.

The fuselage is an aluminum pipe fitted to the diameter ofthe turbojet that is inside it. It’s circular leading edge is thickened and rounded to accept varyingintake flow rates without turbulence. It delivers air to the turbojet at ram pressure and high volume. The exhaust leaves the turbojet with adiameter that is smaller than the fuselage pipe. Where the exhaust has expanded to the pipe’s diameter, thepipe ends -- so that the exhaustdoes not contact the pipe and loose thrust.

Since the exhaust has expanded to the fuselage diameter whenit leaves the fuselage, it blends with the airstream with minimum drag. The constant diameter of the fuselageand the mid-fuselage wing placement minimize wing/body interference drag and,at high subsonic speeds, prevents wing/body shock wave drag.

Fuel is carried in the wings, which are wet inboard of thetail booms. Actuators for theflaperons and the tail ruddervators are in the booms, as is the landinggear. The radio control and flightcontrol electronics are in a wing compartment.

The unmatched low drag of this very simple design canincrease the agility of slower recreational model airplanes -- simply byinstalling a turbojet with one third the thrust and using low speed airfoils.


Day Chahroudi, [email protected]