LUNEX (1961)

Soon after the Soviet Union launched Sputnik 1 on October 4, 1957, the U.S. Air Force launched "Lunar Observatory" and "Strategic Lunar System" studies. The sky no longer seemed the limit for Air Force pilots. On October 1, 1958, however, the civilian National Aeronautics and Space Administration (NASA) opened for business and began work on Project Mercury, the U.S. project to launch a man into space. Piloted spaceflight was seen by many in government as a one-off stunt for garnering Cold War prestige. The job went to NASA mainly so that it would not interfere with more consequential Defense Department space projects, such as development of intercontinental ballistic missiles and surveillance satellites.

On April 12, 1961, the Soviet Union launched Yuri Gagarin, the first man to reach space, on board the Vostok 1 spacecraft. The new Kennedy Administration responded to this new U.S. defeat on the space frontier on May 25, 1961, by calling for an American on the moon by the end of the 1960s.

Four days later, the Air Force released its classified Lunar Expedition (LUNEX) report. It identified the four "major 'prestige' milestones" for its proposed moon program. The first manned Earth-orbital flight of the LUNEX Reentry Vehicle would occur in April 1965. The first manned circumlunar flight in September 1966 would be followed by the first manned lunar landing in August 1967. Just five months later, in January 1968, the U.S. would establish the first permanent moon base. The LUNEX program, which would cost upwards of $7.5 billion by 1971 and would employ about 70,000 people in American industry, would need approval by July 1961 in order to place the first crew on the moon in August 1967.

The three-stage Space Launching System booster rocket would be the workhorse of the LUNEX program. Barges would deliver rocket components to an elaborate seaside launch facility. The report proposed as candidate launch sites Cape Canaveral in Florida, Port Arguello in California, Corpus Christi in Texas, and stretches of the Georgia and South Carolina coasts. The Space Launching System would be capable of boosting 350,000 pounds of payload into 300-mile-high Earth orbit or 134,000 pounds directly to the moon's surface.

The LUNEX program would rely on two types of lunar lander. The automated Cargo Payload lander would comprise a Lunar Landing Stage and cargo with a mass of up to 45,000 pounds. The Cargo Payload lander would bear equipment and supplies for lunar exploration to the moon ahead of the Manned Lunar Payload lander.

The Manned Lunar Payload would comprise a Lunar Landing Stage, a Lunar Launch Stage, and a 20,205-pound LUNEX Reentry Vehicle (images above). The Manned Lunar Payload, which the Air Force report called "the largest single development objective of the LUNEX program," would measure nearly 53 feet from nose to tail and 25 feet in diameter at the bottom of the Lunar Landing Stage, where it would join to the top of the third stage of the Space Launching System. The LUNEX Reentry Vehicle was a triangular lifting body with twin tail fins, twin winglets, and a dome-shaped nose.

The LUNEX piloted mission would begin when three astronauts entered the Manned Lunar Payload. The Space Launching System would then boost the Manned Lunar Payload and crew directly to the moon with no stop in Earth orbit. Abort options during launch would include separating the LUNEX Reentry Vehicle from the malfunctioning booster and gliding to a nearby runway.

Flight to the moon would last 2.5 days. The Manned Lunar Payload would touch down near the pre-landed Cargo Payload. The conical Lunar Landing Stage would include four descent engines and four landing feet shaped like horizontal cylindrical tanks with hemispherical end caps. Abort options during descent would include blasting free of the Lunar Landing Stage using the Lunar Launch Stage, then using the single Lunar Launch Stage engine to carry out a dangerous rough landing. The crew would then abandon their wrecked Manned Lunar Payload and use a pre-landed backup Manned Lunar Payload to fly home to Earth.

Assuming a safe landing on the lunar surface, however, the Manned Lunar Payload's nose would point upward toward the black sky. The LUNEX Reentry Vehicle's aft section would include two decks providing living quarters for the crew during their stay on the moon. A hatch in the lower deck's floor would lead down through the lifting body's tail to a bell-shaped airlock in the Lunar Launch Stage. LUNEX explorers would then exit a hatch in the Lunar Launch Stage's side and clamber down a sloping ladder to the lunar surface. The first landing mission would remain on the moon for about five days.

The spent Lunar Landing Stage would serve as a launch pad when time came for the Lunar Launch Stage to blast the LUNEX Reentry Vehicle off the moon. No abort options would exist during this mission phase, so the Lunar Launch Stage would demand a high level of reliability. The Lunar Launch Stage/LUNEX Reentry Vehicle combination would fly directly back to Earth with no stop in lunar orbit. Moon-Earth transit would last 2.5 days.

The astronauts would cast off the Lunar Launch Stage just before the LUNEX Reentry Vehicle reached Earth's atmosphere. As reentry deceleration ended and gliding flight began, the pilot would eject heat shields covering the forward viewports and the nose landing wheel, deploy landing skids, and then guide the lifting body to an unpowered landing on a runway at Edwards Air Force Base, California.

The Air Force report recommended that an automated probe such as NASA's proposed Lunar Orbiter map the moon ahead of the LUNEX piloted mission. In May 1961, when the LUNEX report was completed, lunar maps included no features smaller than about 16 miles wide. It also suggested that NASA's automated Surveyor landers be used to land radio/flashing light beacons on the moon to aid LUNEX pilots, and called for an automated sample-return mission to collect a subsurface sample before lunar base design began.

Lunar Exploration Plan - LUNEX, WDLAR-S-458, Headquarters, Space Systems Division, Air Force Systems Command, May 29, 1961.