Editing Zero-length launch (section)

== ZELMAL (zero-length launch mat landing)==

The ZELMAL program investigated the possibility of a zero-length landing. The program was conducted 1953 and 1954. It involved a Republic {{nowrap|F-84}} aircraft and an inflatable rubber mat. The aircraft would perform a zero-length landing by catching an arrester cable with a tailhook, similar to an aircraft carrier landing. The aircraft would then drop onto the rubber mat. A number of unmanned tests were performed before two piloted ZELMAL tests in 1954. In both cases the pilots suffered spinal injuries. The program was not continued after that.<ref>{{Cite book |last=Markman |first=Steve |url=https://www.worldcat.org/oclc/46790785 |title=Straight up : a history of vertical flight |date=2000 |publisher=Schiffer Pub |others=William G. Holder |isbn=0-7643-1204-9 |location=Atglen, PA |pages=147–149 |oclc=46790785 |quote=By the early 1950s, short ramps were used routinely to launch early cruise missiles. Engineers figured that perhaps this concept would work just as well for manned aircraft. But eliminating the runway for launch only solved half of the problem... one still would be needed for landing. But perhaps not. Thus was born the ZELMAL (ZEro-length Launch and MAt Landing) program. A rocket would be used to launch a fighter aircraft, then use an inflatable rubber mat, an arresting cable, and a tailhook for the landing. The mat they came up with measured 80 x 400 feet, was 30 inches thick, and had a slick surface coated with a lubricant to assure a smooth landing. [...] The first mat landing was performed on June 2, 1954, but was unsuccessful. The aircraft, S/N 51-1225, was piloted by a Martin Aircraft test pilot. The tailhook missed the arresting cables and tore through the mat surface, tearing open three air cells. Apparently the test pilot was not aware that the F-84 had a tail-hook/airplane flap interconnect system that automatically retracted the flaps when the tail hook contacted the arresting cable, or that he had a manual override switch. The momentary contact between the tail hook and the mat was enough to cause the flaps to retract and the aircraft to settle on the mat too quickly. Complicating the problem was the slow engine response to the pilot's full throttle command. The F-84 bounced off the mat, skidded across the lakebed, and was damaged beyond economical repair. The pilot received back injuries that grounded him for several months.}}</ref>