on a pylon. The first flying boat to utilize the gull wing configuration may have been the Short Knuckleduster, which first flew in 1933. The Dornier Do 26, a high-speed airliner and transport platform, of which six aircraft were built, made its first flight during 1938. The configuration was also used on the US Navy's PBM Mariner and P5M Marlin maritime patrol aircraft. The emergence of long range, land-based jets in the 1950s and the subsequent demise of the seaplane prevented widespread use of the gull wing, although it was still used in some post-war designs, like Beriev Be-12 Chaika (the name means 'the gull' in Russian). Examples: Beriev Be-6 Dornier Do 26 Martin P5M Marlin Piaggio P.136 Short Knuckleduster Landplanes During the late 1920s, the gull wing design found its way into landplanes. In 1928, the Polish aviation designer Zygmunt Pulawski developed the PZL P.1, a experimental fighter aircraft; a major innovation of the P.1 was its relatively high-mounted gull wing. Seeking to protect his new wing arrangement, Pulawski filed for an associated patent for this wing arrangement during the following year. The arrangement devised by Pulawski has been referred to as the "Pulawski Wing" or the "Polish Wing". The P.1 led to a production model, the PZL P.7, of which 149 were was produced between 1932 and 1933. The gull wing was used to improve visibility in a high wing arrangement, because such wing could be thinnest by the fuselage, and in theory should limit pilot's view no more than A-pillars of a windscreen in a car body. It was used on multiple fighter aircraft, including the PZL P.11 and Soviet Polikarpov I-15. The PZL P.11 was a further improvement of the P.6 that was in production throughout the early to mid 1930s. It possessed various cutting-edge features for the era in addition to the high-mounted gull wing, such as its all-metal structure and its metal exterior; according to aviation author Jerzy Cynk, the P.11 was commonly considered to have been the most advanced fighter aircraft of its kind in the world upon its introduction. The P.11 served as Poland's primary fighter aircraft during the mid to late 1930s, participating in the Polish campaign of 1939 to resist an invasion by neighbouring Nazi Germany. As a consequence of the rapid aeronautical advances made during the late 1930s, the P.11 was outclassed by newer fighters such as the Messerschmitt