Smoking Albatross—a remote-controlled, rocket-powered airplane

For simplicity’s sake, I chose a square fuselage cross-section with a side length of 70 mm. The model, ready for launch, has a length of 1160 mm and a wingspan of 1000 mm. Its weight, including propellant charges and the RC system, is 1,040 g. At the very rear of the fuselage, I installed a sheet-metal can that held three D12-3 (Estens) propellant charges. The technical specifications for this propellant charge are 3.95 kp, 20 N/sec, burn time 1.5 sec, maximum takeoff weight 410 g, and weight 42 g per charge. This aircraft is controlled via ailerons and an elevator on the leading edges. A third servo on the prototype allowed me to deploy an emergency parachute. Soon I was ready for the maiden flight.

My club mate Sigi towed the model behind his plane using the piggyback method to an altitude of about 100 m. After releasing the tow rope, I tried to control the model: the result was that it pitched nose-down and went into a nosedive. In desperation, I deployed the parachute. Unfortunately, it was immediately torn off—and the model crashed hard. That very evening (and into the early morning), I repaired and improved the aircraft. The elevator was enlarged, the center of gravity was shifted backward, and the angle of attack was increased. Then I got back to work. Much to the annoyance of the spectators, the model now flew flawlessly. It was wonderfully easy to control and

landed gently. After further test flights, I was able to safely remove the parachute. The launch was performed using a special ramp. Two parallel curtain rails serve as guides. Curtain gliders attached to the bottom of the fuselage ensure smooth and precise guidance. An amateur photographer captured the launch of the rocket glider on film using a motorized camera. Ignition occurred simultaneously.

The model launched successfully and left a trail of smoke as it climbed. After reaching its maximum altitude, I was able to control it without any problems. The flight ended, as planned, with a smooth landing. Depending on the wind, the flight lasts about 60 seconds. In subsequent flights, the rocket glider repeated its performance.

These achievements were recognized with first place at the 1979 Swiss Model Rocket Flight Day. Arthur Hunziker

Right: The author of our RC rocket report, Arthur Hunziker of the Kulm Model Flying Club (Region 4), standing in front of his remote-controlled, rocket-powered Delta model, ready for launch ...

Launch phase (0.0 sec) during ignition. Light smoke is already visible at the rear of the rocket.

... 0.2 sec

... 0.4 sec

Above: Burned-out Estes D12-5 propellant charges.

Left: Final launch preparations on the launch pad.

... 0.6 sec

and 0.8 sec