<P> The first cost - plus - incentive - fee contract to Boeing was for $19,000,000 and called for delivery of the first LRV by 1 April 1971 . Cost overruns, however, led to a final cost of $38,000,000, which was about the same as NASA's original estimate . Four lunar rovers were built, one each for Apollo missions 15, 16, and 17; and one used for spare parts after the cancellation of further Apollo missions . Other LRV models were built: a static model to assist with human factors design; an engineering model to design and integrate the subsystems; two one - sixth gravity models for testing the deployment mechanism; a one - gravity trainer to give the astronauts instruction in the operation of the rover and allow them to practice driving it; a mass model to test the effect of the rover on the LM structure, balance, and handling; a vibration test unit to study the LRV's durability and handling of launch stresses; and a qualification test unit to study integration of all LRV subsystems . A paper by Savero Morea gives details of the LRV system and its development . </P> <P> LRVs were used for greater surface mobility during the Apollo J - class missions, Apollo 15, Apollo 16, and Apollo 17 . The rover was first used on 31 July 1971, during the Apollo 15 mission . This greatly expanded the range of the lunar explorers . Previous teams of astronauts were restricted to short walking distances around the landing site due to the bulky space suit equipment required to sustain life in the lunar environment . The range, however, was operationally restricted to remain within walking distance of the lunar module, in case the rover broke down at any point . The rovers were designed with a top speed of about 8 mph (13 km / h), although Eugene Cernan recorded a maximum speed of 11.2 mph (18.0 km / h), giving him the (unofficial) lunar land - speed record . </P> <P> The LRV was developed in only 17 months and performed all its functions on the Moon with no major anomalies . Scientist - astronaut Harrison Schmitt of Apollo 17 said, "The Lunar Rover proved to be the reliable, safe and flexible lunar exploration vehicle we expected it to be . Without it, the major scientific discoveries of Apollo 15, 16, and 17 would not have been possible; and our current understanding of lunar evolution would not have been possible ." </P> <P> The LRVs experienced some minor problems . The rear fender extension on the Apollo 16 LRV was lost during the mission's second extra-vehicular activity (EVA) at station 8 when John Young bumped into it while going to assist Charles Duke . The dust thrown up from the wheel covered the crew, the console, and the communications equipment . High battery temperatures and resulting high power consumption ensued . No repair attempt was mentioned . </P>

Who drove the first lunar vehicle on which apollo mission