 A test that was similar to the test of a pusher plate occurred as an accidental side effect of a nuclear containment test called "Pascal-B" conducted on 27 August 1957.The test's experimental designer Dr. Robert Brownlee performed a highly approximate calculation that suggested that the low-yield nuclear explosive would accelerate the massive (900 kg) steel capping plate to six times escape velocity.The plate was never found but Dr. Brownlee believes that the plate never left the atmosphere, for example it could have been vaporized by compression heating of the atmosphere due to its high speed.