Cosmos 57 was an unsuccessful Voskhod 2 test mission. Immediately after orbital insertion, airlock and spacesuit inflated normally. Then ground controllers sent commands to the spacecraft simultaneously instead of sequentially as planned. The signal accidently set off the self destruct mechanism (designed to prevent falling into enemy hands). The spacecraft blew up past Kamchatka on the first orbit. No other test or backup spacecraft was built with an EVA port. The decision was made to go ahead with Vosthod 2 anyway, due to one year leadtime to construct a replacement. Planned follow-on Voskhod missions were cancelled, including the Air Force version, long duration one man flight.