In radio controlled aircraft, hotliner is a term used to describe a fast sailplane with an electric motor. The range of what is often desribed as a hotliner varies from a sailplane with ailerons to 3000-watt competition F5B planes. General traits of a hotliner are:
- Sailplane with at least aileron and elevator control.
- Electric motor.
- Can climb at an angle of 70 degrees or more.
Hotliners have been around since the early 1990s and became popular almost a decade later.
Hans-Dieter Levin first proposed this term in his test of the Aeronaut Sinus in a German magazine. Originally, it was an electric sailplane with ailerons, capable of flying a bit faster than the usual rudder and elevator gasbags typical for that period. He tested the Sinus with a Speed 600 motor with an 8x4.5 prop and a 7 cell Ni-Cd as well, so the fast, >70° climb was not part of the original definition. The hotliner term has since evolved, fast climb also seems to be part of it these days. Not-so-fast aileron electrics have thus become known as "warmliners."