The Socata ST-10 Diplomate was a French four-seat civil light aircraft.

It was a development of the GY-80 Horizon, and was initially known as the Super Horizon 200, later the Provence, before finally being named the ST-10 Diplomate.

The first prototype flew on 7 November 1967,[1] production beginning in 1970.

Production ended in 1974, with a total of 56 built.

[2] Data from Jane's All the World's Aircraft 1974-75[1]General characteristics Performance