The BD-4 is one of the first true homebuilt aircraft, meaning that the buyer did not just receive a set of plans rather the entire kit with all the parts needed to build a complete plane. The first kits were sold in 1968 and the aircraft remains popular today even though the kits are no longer available. The BD-4 enjoys one of the best safety records of all homebuilt aircraft and this combined with the ease of construction and a long list of optional equipment explains the aircraft's continued popularity.