Stingray / Mantaray

Description

EDF stingray and servo manta, undulating-wing control experiments.

Development Log

2020-07-28 — EDF stingray maiden flight
2020-07-28 — EDF stingray new tail control
2020-07-31 — EDF stingray test flights 30.07.20
2020-08-03 — EDF stingray test flights 02.08.20
2021-07-27 — Servo Mantaray testflights 26.07.21
2021-08-12 — Servo Mantaray testflights 05.08.21 (bad video) — normal rudder is ineffective during flapping, only change of amplitude works. i think this is because theres no fixed tail. for more stable turning however i mixed the inverted rudder (left/right flap angle) into the aileron (left/right flap amplitude) on the transmitter , this way theres no danger of sideslipping while doing sharp turns.
2021-08-18 — Servo Mantaray TestFlight 18.08.21 — With new fuselage and paint. The Model has more overweight now
2023-07-05 — Servo manta test ondulating wing system 03.07.23 — test of new ondulating wing system. by the ondulating movement of wings it is possible to move a large surface of wing and bigger amplitude by small motor, the wing can bend more and is still able to produce efficient thrust, however it is not efficient enough yet and also has about 3g overweight. weight: 31g (without lipo) wingspan: 994mm motors: 2x BlueArrawo DS-43 MG-6.0 servo
2023-11-11 — EDF stingray maiden flight 10.11.23 — This is a slightly larger version with some changes to the previous stingray jet I made. Mainly the engine is much larger now to optimise edf speed, the shape is not completely square anymore to move the tail closer to the engine, plus the airfoil has double thickness and is symmetrical to have more stall tolerance and lift on the relatively small surface. The test was successful but sometimes I couldn’t steer to the other opposite side it seems the tail mechanism allows twisting too much which decreases its effect on yaw and the adverse yaw from ailerons may win
2023-11-16 — EDF sting ray testflight 13.11.23 — the model YAW movement is not very responsive and it may lead to a unrecoverable death spiral. this will be fixed by making the mechanism twist the tail too as in the first version of the model. The FEICHAO 40A ESC has started to burn in this test flight and needs replacement too.