Project Waterpump (alternately, Operation Waterpump, or simply Waterpump) was a secretive support operation by the U.S. Air Force to train and nurture into existence the Royal Lao Air Force (RLAF). The United States had decided to covertly support the Kingdom of Laos in the Laotian Civil War as the Lao fended off a North Vietnamese invasion. The nascent RLAF was seen as a force multiplier but needed pilots and technicians. The 40-man Detachment 6, 1st Air Commando Wing, code named Waterpump, was forwarded to Udorn Royal Thai Air Force Base for this training duty in March 1964. They would remain on duty through the truce of 21 February 1973. Their first hasty assignment was transition training to the T-28 Trojan for American civilian pilots; the resulting A Team would exist through 1967. The Air Commandos also conducted final training for Royal Thai Air Force (RTAF) mercenary pilots; the resultant B Team would serve until 1970. Besides putting a polish on graduate pilots, the Waterpump detachment trained Lao pilots from scratch. The RLAF's high pilot casualty rate made bringing the RLAF rosters up to strength a long grind.
Waterpump grew beyond its original training mission. From 19–29 July 1964, some Air Commandos were smuggled into Laos as an improvised Tactical Air Control Party for Operation Triangle. The success of the endeavor led to a forward air control system being set up for the war's duration. Some Waterpump personnel were later infiltrated into Laos to help staff regional Air Operation Centers. With Waterpump help, by war's end the RLAF had grown from 20 to 75 T-28 strike aircraft; it also operated ten AC-47 gunships and 71 support aircraft.