Burnelli Bomber SAB AB-20.

The Burnelli SAB AB-20 and AB-21 were large 4-engine French bombers built in the early 1930s. They featured a lifting body of thick airfoil section between the inner engines.

A second aircraft, the Burnelli SAB-21, had different engines and cleaner aerodynamics but no more were built. It was an attempt to make plane's central body deep enough to house most of the load carried, and to act as a lifting surface.

Burnelli SAB's the central portion of the wing had been greatly thickened to give space for crew, bomb load, fuel tanks, etc. The plane was fitted with four Lorraine "Courlis" engines of 600hp each, giving the machine a total power of 2400hp.

The Burnelli SAB AB-20 and AB-21 were of all-metal construction, and had a gross weight of some 13500kgs each. The central body had a large bomb accommodation - at least up to a total bomb load of 2500kg.

Later the SAB AB-20 was converted into ... a cannon aircraft! This was a desire of the Navy France to have a plane that could attack the armored ships of the enemy.

A 75-mm field gun was used as the main weapon of a new aircraft. The installation was placed in the fuselage. Re-equipment was completed at the end of August 1934, after which the plane made several flights. The test result said that the weapon presented a greater danger to his carrier than for the enemy.

All the crews that flew on this huge plane suffered from vibrations with which the SAB design bureau did not know what to do.

The Burnelli SAB AB-20 and AB-21 career approached the end in 1935 according to the press of that time.

Both machines had a range of about 965 kilometers. The estimated top speed was 215km/h and the cruising speed 195km/h. The theoretical ceiling was 6500m. The total length was 21.90 meters, and the height was 6.84 meters.