A total of 25 Black Knight launch vehicles were constructed at a cost of just over £40,000 each. A single rocket (BK02) was used for ground testing. One (BK11) was expended as part of the European Launcher Development Organisation (ELDO) initiative as an investigation of range facilities. The majority, 21, were fired as part of re-entry experiments; if they had been used as launch vehicles for satellites, the majority of these firing would have successfully attained orbit. The remaining two rockets (BK02 and BK22) were preserved and are now kept on static display in museums in Edinburgh and Liverpool.