Repeated collapses during testing led to reinforcement of the nose landing gear. Many require little more than attachment of the wing and landing gear. The aircraft was designed with tricycle landing gear. The landing caused parts of the landing gear to break. The aircraft landed as an emergency landing without the landing gear nose. The Bombardier Dash 8 is notorious for its landing gear problems. The PBM-5A was an amphibian with retractable landing gear. It was one of the first jet propelled aircraft built with fixed landing gear. Some targets equipped with landing gear were redesignated as GQM-15As. Ground carriage is a long term (after 2030) concept of flying without landing gear. The Cessna Airmaster was among the first aircraft to use spring steel landing gear. Another design feature was tricycle landing gear. The issue was resolved by a design change to the outboard main landing gear doors. There are other related systems which use nets to catch aircraft wings or landing gear. Some of the very earliest B-26s suffered collapses of the nose landing gear.