table: [['category', 'speed (km / h)', 'speed (mph)', 'vehicle', 'pilot', 'date'], ['rocket - powered aircraft', '7258', '4510', 'north american x - 15', 'william j knight', '3 oct 1967'], ['manned air - breathing craft', '3530', '2194', 'lockheed sr - 71 blackbird', 'eldon w joersz', '28 jul 1976'], ['propeller - driven aircraft', '870', '541', 'tupolev tu - 114', 'ivan soukhomline', '00 jan 1960'], ['piston - engined propeller - driven aircraft', '850.1', '528.33', 'grumman f8f bearcat rare bear (n777l)', 'lyle shelton', '21 aug 1989'], ['helicopter', '401.0', '249.1', 'westland lynx 800 g - lynx', 'john egginton', '11 aug 1986'], ['glider (sailplane)', '306.8', '190.6', 'schempp - hirth nimbus - 4dm', 'klaus ohlmann and matias garcia mazzaro', '22 dec 2006'], ['human - powered aircraft', '32', '19.8', 'mit monarch b', 'frank scarabino', '1 may 1984']]
ref: the Human Powered Aircraft is the slowest Vehicle Of the Category
template: the [ENT] is the slowest [ENT] the [ENT]