Tow and Glide

Model and simulate the flight of an aircraft through the atmosphere. In this example, a glider aircraft is towed up to a cruising altitude by an electric aircraft and released.

Model of the Glider and Electric Aircraft

The glider and the electric aircraft are connected to autopilots. Both the autopilots are given the same reference trajectory until the cruising altitude. At the cruising altitude, the glider is released and it follows its own trajectory. A towing rope with a parameterized length connects the glider with the aircraft.
The glider aircraft is towed up to 2,000 m (6,562 ft) by an electric aircraft from the initial altitude of 100 m (328 ft).

Check the Flight Response

The glider reaches the cruising altitude at around 13.5 min, after which the glider is released and given a command to descend. At around 15 min, the glider is given a command to fly at a constant altitude for some time. Eventually, both the altitude and velocity of the glider start to oscillate, as it cannot sustain the given altitude with the decreased velocity. The oscillation ends as the glider catches up with the descending reference altitude command.
Pipistrel and Schweizer represent the electric aircraft and glider, respectively. The top plot shows the altitude and the bottom plot shows the velocity.

Model and Simulate the Flight of an Aircraft Using the Aircraft Library