From their early use as target drones and remotely piloted combat vehicles, UAVs took on a new role during the Vietnam War: stealth surveillance.

In 1960, the U.S. Air Force began its first stealth aircraft program The resulting AQM-34 Ryan Firebee was air-launched and controlled from a DC-130 director aircraft. After a mission, the Firebee UAV was directed to a safe recovery area, where it deployed its parachute and was picked up by a helicopter. From October 1964 to April 1975, >1,000 Ryan Firebee UAVs flew >34,000 operational surveillance missions over Southeast Asia. The Firebee was extremely reliable; 83 percent of the Firebees flown during the Vietnam War returned to fly another day.

With the shooting-down of Gary Powers' U-2 spy plane over Russia in 1960, the CIA began work on a new UAV, invulnerable to attack. Lockheed developed a high-speed, ultra-stealth UAV, producing a single D-21 UAV in 1965. The Mach-4 vehicle, the fastest UAV in history, was carried on the back of a piloted M-12 "mother" aircraft and had a range of 3,000 miles. It operated at a height of 80,000 feet and was covered in Lockheed's signature plastic anti-radar coating, a precursor to the stealthy outer skin of today's Lockheed F-117 Stealth Fighter and B-2 Stealth Bomber. D-21 flew three failed missions before it crashed and sank on the fourth at an undisclosed location.

The success of the Firebee continued through the end of the Vietnam War. In the 1970s, while other countries began to develop their own advanced UAV systems, the U.S. set its sights on other kinds of UAVs.

Israel secretly purchased 12 Firebees from the U.S. in 1970, modified them, and designated them Firebee 1241 UAVs. These Firebee 1241s played an important role in the 1973 Yom Kippur War between Israel, Egypt, and Syria, both as reconnaissance vehicles and as new kinds of UAVs: decoys. On the 2nd day of the war the Israelis deployed their fleet of armed Firebees to lead attacks against Egyptian air defenses along the Suez. The Egyptians fired their entire inventory of surface-to-air missiles at the Firebees—43 missiles in all. The Firebees successfully evaded 32 of the missiles and destroyed 11 with their Shrike anti-radar missiles.

In 1970, an RC-121 communications intelligence (COMMINT) monitoring aircraft was shot down over the Yellow Sea, killing the crew on board and spurring the U.S. military to develop new UAVs fitted for COMMINT acquisition and able to fly at high altitude, above the range of enemy missiles. Ryan Aeronautical set to work modifying Firebee target drones so that they could eavesdrop on enemy radio messages and take photographs from above 60,000 feet. The resulting Ryan Special Purpose Aircraft (SPA) 147, which could fly for eight hours carrying a 300-pound camera was the first long-haul UAV equipped for COMMINT at high altitude.

During the late 1970s and throughout the 1980s, the Israeli Air Force, an aggressive UAV developer, pioneered several important new UAVs, versions of which were integrated into the UAV fleets of many other countries, including the U.S.

In 1978, Israel Aircraft Industries (IAI) built Scout, a piston-engined aircraft with a 13-foot wingspan made of fiberglass. It’s low radar signature, coupled with it’s small size, made it almost impossible to shoot down. It could transmit real-time, 360-degree television camera surveillance data. In 1982, during the Bekaa Valley conflict, Israel used a fleet of Scouts to search out Syrian missile sites and entice the Syrians to activate their radars. These allowed Israeli bombers to destroy all but two Syrian missile sites (17 in all), allowing them to fly unchallenged in the skies.

Israel built the Pioneer UAV in the late 1980s and the U.S. military acquired more than 20 of them, which became the first small, inexpensive UAVs in the modern American military forces. The rocket-boosted Pioneer takes off from a makeshift runway or carrier flight decks.  The Pioneer can operate up to 5 hours with a 75-pound (34 kg) payload. It flies with a gimbaled EO/IR sensor, relaying analog video in real time via a C-band line-of-sight (LOS) data link. Since 1991, Pioneer has flown recon missions during the Persian Gulf, Somalia (UNOSOM II), Bosnia, Kosovo and Iraq conflicts. During the Gulf War, they flew a total of 533 sorties.

A drone helicopter built by Gyrodyne Company for use as a long-range anti-submarine weapon on ships that would otherwise be too small to operate a full-sized helicopter. The DSN-1 was powered by a Porsche YO-95-6 72 hp piston engine and carried one Mark 43 homing torpedo. The DSN-3/QH-50C (last model in production, in which a 255 hp (190 kW) Boeing T50-4 turboshaft engine replaced the piston engine and the payload was increased to two Mk 44 torpedoes. Three hundred and seventy eight QH-50C were produced before production ended in January 1966.  Several are still used today for various land-based roles.

The 1970’s saw several VTOL UAV developments, such as the Bombardier (Canadair) CL-227 Sentinel but received little consideration due to their cost and technical immaturity. Fixed wing UAVs were considered more mature platforms and had demonstrated their utility in combat.

The CL-227 Sentinel was developed by Bombardier's Canadair Defense Systems Division (early version called the Peanut; 1978) The CL-227 is a remotely controlled helicopter with a turbine engine driving a pair of co-axial counter-rotating rotors. A successful naval development was completed to demonstration stage in 1992. The Sentinel is roughly 6 feet tall, standing on four castered legs. Support vehicles include a flatbed pickup transporter with winch and launch platform, and a control / communication van, each with utility trailers.