4 Lesser-Known Polish Aircraft of World War II

During the 35-day invasion of Poland in 1939, German forces encountered fierce resistance from the Polish military, including its air force. Despite being outnumbered and outgunned, the Polish air force destroyed or severely damaged around 561 German aircraft, which was about a quarter of Germany’s available planes at the time. Poland’s air force operated approximately 350 combat aircraft during this period, many of which were domestically designed and manufactured. However, Poland faced significant industrial and financial challenges leading up to the war. Much of its history was marked by foreign occupation, leaving it with limited industrial infrastructure. In the interwar years, Poland remained largely agrarian, and the global economic downturn of the Great Depression further hindered its ability to produce military equipment. Despite these limitations, Polish engineers managed to develop several unique aircraft. Here are four lesser-known Polish planes that played a role in the country’s defense.

PZL P.7

The PZL P.7 was a product of the innovative design work of Zygmunt Puławski, who introduced a revolutionary gull-wing design. First flown in 1930 and entering production in 1932, the P.7 was constructed entirely of metal, making it advanced for its time. The gull-shaped wings provided excellent visibility for pilots, enhancing maneuverability and lift. Additionally, the aircraft’s compact design allowed it to operate from short and poorly maintained airstrips, which became essential after major Polish airfields were bombed during the German invasion.

Powered by the Bristol Jupiter 7F engine, the P.7 delivered 527 horsepower, reaching a maximum speed of 317 kilometers per hour at an altitude of 4,000 meters. Armed with two 7.9 mm wz.30 machine guns, it was considered adequate for its early 1930s role. However, by 1935, the P.7 had become outdated, and its replacement, the P.11, began taking over frontline duties. Despite its obsolescence, 30 P.7s were still in service during the invasion of Poland. These aircraft managed to shoot down seven German planes before being overwhelmed by superior enemy aircraft. Most surviving P.7s were either destroyed, captured by German or Soviet forces, or fled to Romania, where they were confiscated and integrated into the Romanian air force.

PZL P.11

The PZL P.11 was designed to replace the P.7 and entered service in 1934. Like its predecessor, the P.11 featured a gull-wing design, but it was equipped with a more powerful British Mercury engine, producing 645 horsepower. This allowed the aircraft to reach a top speed of 390 kilometers per hour and achieve a climb rate of 13 meters per second. Despite these improvements, the P.11 retained features that made it outdated by 1939, such as its fixed landing gear and open cockpit.

The P.11 was armed with two wz.36 machine guns, though later models could carry an additional two guns mounted on the wings. It also had limited ground-attack capabilities, with the ability to carry four 12.5-kilogram bombs. By the time of the German invasion, about 130 P.11s were in active service. Although German aircraft, such as the Bf 109, were superior in speed and firepower, Polish pilots used the P.11’s agility and familiarity with local terrain to their advantage. The P.11 contributed to the destruction of around 110 German aircraft during the campaign, though many were eventually destroyed or captured. A few P.11s managed to escape to Romania, and only one has survived to this day, now displayed in a Polish museum.

PZL P.23 Karas

The PZL P.23 Karas was designed as a light bomber and reconnaissance aircraft, reflecting Poland’s strategic emphasis on aerial support following the Polish-Soviet War of 1920. Development began in the early 1930s, and the final production model was introduced in 1935. Early versions of the P.23 faced significant challenges, particularly with the Pegasus II engine imported from Britain, which was prone to mechanical failures. These early models, designated as P.23A, were quickly relegated to training roles. A more reliable version, the P.23B, was powered by the Pegasus VIII engine, delivering 720 horsepower.

The P.23B had a maximum speed of 319 kilometers per hour, though pilots were advised not to exceed this speed due to structural limitations. Its armament included one forward-firing wz.36 machine gun, a dorsal gun, and a ventral gun for defensive purposes. For offensive operations, it could carry up to 700 kilograms of bombs, making it effective in light bombing roles. However, its defensive armament proved insufficient against German fighters.

Poland also developed an export variant, the P.43, which was sold to Bulgaria. Unfortunately, the focus on export production left Poland with fewer aircraft to defend itself in 1939. Although five P.43s were confiscated by Polish authorities before they could be shipped, the additional aircraft did little to impact the course of the campaign. Most P.23s were destroyed during the invasion, though their bombing missions inflicted some damage on advancing German columns.

PZL.37 Los

The PZL.37 Los was Poland’s most advanced bomber at the outbreak of World War II. Designed in the mid-1930s, it featured a modern twin-engine layout and could carry up to 2,500 kilograms of bombs—a remarkable capacity for its time. The aircraft’s sleek design and retractable landing gear made it faster and more agile than many contemporary bombers, with a top speed of 412 kilometers per hour.

The PZL.37 was equipped with defensive armament, including three wz.37 machine guns placed in dorsal, ventral, and tail positions. Despite its advanced design, the PZL.37 faced production delays and Poland entered the war with fewer than 120 units available. During the invasion, these bombers were used primarily for attacking German ground forces and supply lines. While they achieved some success, they were highly vulnerable to German fighters due to insufficient defensive armament.

Several PZL.37s managed to escape to Romania, where they were integrated into the Romanian air force. Others were captured by German and Soviet forces and used for testing and training. Despite its limited numbers, the PZL.37 remains a symbol of Poland’s efforts to develop modern military aviation under challenging circumstances.