Mbabane - A Swazi military aircraft overshot a runway and crashed into a sugar cane field - causing no serious injuries except to the kingdom's tiny air force, which is now left with just three planes.

Swazi Army spokesperson Lieutenant Khanya Dlamini said the accident occurred on Saturday in eastern Swaziland, where the plane had been forced to land at a sugar plantation landing strip because of bad weather at the country's only airport.

When the pilots were given clearance to take off again for the airport, they failed to achieve proper altitude and instead ploughed the 24-seat airplane through 50m of sugar cane before coming to a stop in a field.

"Two pilots were aboard the aircraft, an Arava 201 propeller-driven craft, and they walked away from the craft," Dlamini said.

Swaziland's army has never engaged in a foreign conflict, and is used primarily domestically during political protests.