by JOSEPH TREVITHICK
In April 1980, the Pentagon sent elite troops into Iran to rescue American hostages held by student revolutionaries. For a host of reasons, Washington aborted Operation Eagle Claw after the force got to its first waypoint—codenamed Desert One—deep in eastern Iran.
As the special operators got ready to come home, one of their RH-53D helicopters smashed into a transport plane loaded with fuel. The aircraft exploded, killing eight commandos.
It was a fiasco. But had the operation gone according to plan, the RH-53Ds would have refueled, and then picked up the freed hostages and their rescuers inside the Amjadien soccer stadium near the American embassy compound in Tehran.
The Pentagon’s solution to the disaster—although the military never went beyond testing it—was a C-130 transport plane with rocket motors mounted on its sides.
Instead of a complicated strategy involving short-range helicopters refueling in the desert, the military built a lumbering plane that could drop directly into a soccer stadium before coming to a screeching halt.
After the debacle, an investigation into Eagle Claw by the Joint Chiefs of Staff zeroed in on various equipment failures during the mission, especially the RH-53D helicopters. The Navy designed the helicopters to hunt mines at sea—not fly through the desert at night.
“The unsatisfactory performance of the U.S. Navy RH-53Ds at Desert One had convinced planners that an improved rotary-wing capability was needed if the mission was to be a success,” retired Col. Jerry Thigpen wrote in The Praetorian STARShip: The Untold Story of the Combat Talon.
The fallout from the failed operation quickly became a cause célèbre for both Pres. Jimmy Carter and the Pentagon’s senior leadership. But with 52 Americans still trapped in Tehran, American officers immediately looked into giving the rescue mission another shot.
Some officers proposed replacing the troop-carrying helicopters entirely. But to get rid of the choppers, the Pentagon needed a cargo plane that could take off and land without the need for any real runway.
So in July, the U.S. Air Force started a project—nicknamed Credible Sport—to develop a special C-130 that would fit the bill. Two months later, Lockheed finished the first prototype.
To squeeze into the Amjadien stadium, the unique aircraft had to land with 600 feet or less of space, and then take off with the same distance, according to Air Force documents we obtained through the Freedom of Information Act.
To account for the stadium’s bleachers, the planes had to clear 90-foot obstacles. But “the existing MC-130 … is restricted to landing zones of at least 3,500 [feet],” the now-declassified Air Force messages explained.
To achieve these goals, the Credible Sport Aircraft was radically different from standard Hercules transports. For one, Lockheed bolted rocket motors onto the fuselage and wings.
In theory, the rockets would help bring the Hercules’ to a stop, cushion its landing and then help launch the plane back into the sky. The motors themselves came from old Navy RUR-5 anti-submarine rockets and AGM-45 radar-seeking missiles.
The top-secret transports—variously referred to as XC-130s, XFC-130s or XSC-130s—also had modified wings to help generate more lift at low speeds, and keep everything stable during violent changes in direction.
“In all there were some 20 U.S. Navy, 50 U.S. Air Force, and over 1,000 civilians committed to the project,” Thigpen noted.
Four months after the program started, the first Credible Sport plane—loaded up with rockets—took to the skies for flight tests. The results were both impressive and encouraging.
“The nose gear lifted six feet off the ground after 10 feet of takeoff roll … and the aircraft was airborne within 150 feet of brake release,” Thigpen wrote. “Within the length of a soccer field, it had reached an altitude of 30 feet and an airspeed of 115 knots.”
But on Oct. 29, the functional prototype crashed in spectacular fashion—seen at the end of the video above. Thankfully, the crash didn’t hurt anyone, but it completely destroyed the aircraft.
Still, Credible Sport continued to have some support in the halls of the Pentagon. “My primary purpose in supporting this project … was to obtain a quick increase in the number of MC-130 [air] refuelable aircraft,” Army Maj. Gen. James Vaught wrote in a memo the following month.
Vaught had been in charge of the first rescue attempt, and was developing the next mission. With the Credible Sport prototypes, Vaught had nine special Hercules cargo planes at his disposal for any new rescue scenario. He wanted seven more.
“Attainment of the rocket-assisted capability is a much needed but secondary consideration,” the general added. “Further testing of the rocket concept could be continued once a necessary complement of 16 operational MC-130’s has been acquired.”
In the meantime, Washington had started negotiating with Iran. Ronald Reagan—helped in no small part by the crisis—crushed Carter in the 1980 presidential election.
Reagan’s administration eventually came to an agreement with the new regime in Tehran. In January 1981, Iranian authorities released the remaining captives.
With the rescue mission now moot, the Pentagon’s support for Credible Sport quickly faded. The flying branch’s Tactical Air Command suggested adding some of the aircraft’s features to another specialized MC-130 they were working on at the time, called the Combat Talon II.
“Such capability would also expand mission flexibility,” one of the previously classified memos stated. “Smaller, unimproved fields are more likely to be unoccupied and undefended.”
Maj. Gen. Carl Cathey, then the deputy chief of staff in charge of planning out the Air Force’s requirements, was unconvinced. His office warned that Combat Talon II could prove to be far too expensive—outweighing any benefits.
The changes could “add approximately 22 percent [$100 million] to the total program cost,” Col. John Loh—Cathey’s assistant—warned in a classified response. “[A] solid rationale is needed to support your position.”
Ultimately, the new MC-130Hs used some of the same equipment, but junked the rocket arrangement and other complicated modifications. Today, the Air Force plans to eventually replace the remaining Combat Talon IIs with similar MC-130J Commando II transports.
The Commando II cannot land inside a soccer stadium. But the failure of Eagle Claw inspired the development of other long-range aircraft that can—specifically the tiltrotor V-22 Osprey.
Without rockets, of course.