The French WWII Twin-Engine Fighter-Bomber That Few Knew About

A Desperate Debut in Battle

On May 20, 1940, three Potez 633 aircraft lifted off from a French airfield near Arras. Their mission was to strafe German forces advancing through France. Armed with bombs and machine guns, these twin-engine aircraft were sent into combat as the German advance pushed deep into French territory. However, within just two days, the aircraft was pulled from front-line duty. It was clear that the design could not hold up against the faster and more powerful German fighters.

This marked the brief combat appearance of the Potez 630 series, a group of aircraft developed in the 1930s for a modern French air force. The series was created to meet multiple needs—day and night fighting, escort, reconnaissance, and attack—all in one platform. Yet the aircraft entered war service in a time when France was unprepared for the scale and speed of modern conflict.

A Response to Growing Threats

In the mid-1930s, the French Air Force realized that its older planes would not stand up to new aircraft being developed by Germany. Many of France’s fighters were outdated biplanes or single-engine planes that lacked power or flexibility. On October 31, 1934, the French Ministry of Air called for a new type of aircraft. It would have twin engines, three crew members, and be able to fill many roles—from leading formations to night interception.

The Potez 630 was designed by the company Potez, founded in 1919. Engineers Louis Coroller and André Delaruelle began designing the aircraft in 1935. Their goal was a modern, low-wing monoplane that could handle several missions. The team took inspiration from designs like the British Bristol Blenheim and the German Bf 110.

Development and Early Testing

The prototype flew for the first time on April 25, 1936. It used two Hispano-Suiza radial engines, each providing 670 horsepower. Early test flights showed the plane handled well, but the engines overheated and vibrated too much. In 1937, Potez switched to Gnome-Rhône 14M radial engines, boosting reliability and pushing the top speed to about 295 mph.

The airframe was made of duralumin, with fabric on the control surfaces. A twin-tail design gave it more stability. The cockpit had a large glass canopy, allowing good visibility for all three crew members. Maintenance was made easier with features that allowed for quick repairs in the field.

Variants and Weaponry

By 1938, after trials and adjustments, the aircraft was approved for mass production. Several versions were made. The base Potez 630 was 36 feet long with a wingspan of over 52 feet. It could carry a crew of three and had a range of over 600 miles. Later versions improved on this, with the 631 variant offering more power and weapons.

The 631 had two 20 mm cannons and up to six machine guns. Some versions were made for reconnaissance, with cameras and even more guns. The 633 was a light bomber that could carry up to 400 kg of bombs.

Service Record and Combat Use

By May 1940, more than 700 aircraft were in French service. They were used in night-fighter units, reconnaissance groups, and with naval aviation. Some were sent abroad to countries like Romania and Greece. However, the plane’s shortcomings soon became clear.

When German forces invaded France, the 630 series was quickly outclassed. The German Bf 109 was significantly faster and better armed. In battles like the one near Sedan, Potez aircraft were shot down in large numbers. Without radar, night fighters also struggled to track enemy bombers. The plane that was supposed to represent a modern air force found itself outmatched in its first real test.