Category: Aircraft

On August 5, 1950, a Boeing B-29 Superfortress, operated by the US Air Force and carrying a Mark 4 nuclear bomb, crashed northeast of San Francisco, California. Of the 20 individuals onboard, 12 lost their lives, including Brig. Gen. Robert F. Travis, commander of the 9th Bombardment Wing. The incident also led to the deaths of seven people on the ground.

This is the story of the ill-fated flight.

Boeing B-29 Superfortress

Boeing B-29 Superfortress Enola Gay, 1945. (Photo Credit: US Air Force / Wikimedia Commons / Public Domain)

The B-29 Superfortress played a critical role in shaping the outcome of the Second World War. The first one took to the skies in September 1942, after which the aircraft was sent to Europe. Following Germany’s defeat, it saw action in the Pacific Theater.

The B-29 is perhaps most famous for its role in the atomic bombings of Japan. The Enola Gay dropped Little Boy on Hiroshima on August 6, 1945, while Bockscar deployed Fat Man over Nagasaki three days later. These events not only prompted Japan’s surrender, but cemented the B-29 into aviation history.

In July 1950, following the outbreak of the Korean War, 10 Silverplate (nuclear-capable) B-29s were sent to Guam as a deterrent to China, as it was believed the country might take the opportunity to move against Taiwan. The bombers were also there, in case they were needed in Korea. Each carried a Mark 4 nuclear bomb.

A Boeing B-29 Superfortress crashed in California

Two Boeing B-29 Superfortresses flying over Korea, 1950. (Photo Credit: US Air Force / National Museum of the US Air Force / Wikimedia Commons / Public Domain)

On August 5, 1950, 20 passengers and crewmen boarded a B-29 Superfortress at Fairfield-Suisun Air Force Base, California, one of them being Brig. Gen. Robert F. Travis. Also aboard was a Mark 4 nuclear bomb, which had had its radioactive core removed.

The bomber started down the runway, reaching 125 MPH about three-quarters down the 8,000-foot tarmac. Suddenly, with all of the propellers maintaining 2,800 RPM, the one being operated by the No. 2 engine shot up to 3,500 RPM. The pilot attempted to correct this by feathering, and, reaching 155 MPH, the B-29 took off. However, the No. 3 engine’s propellor also shot up to 3,500 RPM.

To maintain airspeed, the pilot attempted to retract the landing gear, but was unsuccessful. The aircraft’s speed was reduced to 145 MPH. As the bomber wasn’t high enough to clear the terrain ahead of it, the pilot turned around for an emergency landing. While the crew tried to maintain altitude, the B-29 made contact with the ground, striking it at 120 MPH.

The B-29 broke apart and burst into flames. While the escape hatches were all jammed, the crew and passengers were able to exit through holes caused during the crash, as well as windows. Of those onboard, 12 died, with all but one suffering injuries.

Military police, firefighters, men from the air base bakeshop and spectators all ran to help. They were soon ordered to clear the area over fears that the 5,000 pounds of explosives in the Mark 4 would explode. None of them listened and continued trying to help.

Twenty minutes after the crash, the explosives detonated, creating a crater that was 20 yards wide and six feet deep. It also spread the wreckage and fuel over a two-square-mile area. Seven people on the ground were killed.

Aftermath of the devastating crash

Travis Air Force Base, California, 1972. (Photo Credit: US Air Force / Wikimedia Commons / Public Domain)

An official investigation occurred after the fact and found that there had been problems with the B-29 Superfortresses’ engines. An issue had been reported previously and was supposed to be fixed; however, with the engines destroyed and the groundcrew who’d worked on the aircraft dead in the blast, the investigators couldn’t say whether or not it had been fixed.

The crash resulted in changes made to the B-29 operating procedures, with regulations being put in place to ensure all aircraft with the same type of propeller were test-flown after undergoing maintenance.

The greatest legacy of the crash was the renaming of Fairfield-Suisun Air Force Base to Travis Air Force Base, after the brigadier general who perished in the incident. This change was made on October 20, 1950, with a formal renaming ceremony taking place on April 20, 1951.

It wasn’t until 1994 that it was revealed that a nuclear bomb had been onboard the B-29. A public health assessment took place and found that there were no detectable levels of uranium, and the crash site was deemed safe.

The Northrop XP-79 Flying Ram was a rocket- and jet-powered flying-wing fighter designed during the Second World War for the US Army Air Forces. The aircraft had some unique elements, among them its welded magnesium monocoque structure and the fact the pilot needed to man it from a prone position. What’s more, it was developed to ram enemy bombers in mid-air.

Coming up with the idea for the Northrop XP-79

Northrop MX-334, precursor to the XP-79. (Photo Credit: Unknown /  United States Army Air Forces Photographer / San Diego Air & Space Museum / Wikimedia Commons / Public Domain)

The Northrop XP-79 was conceived by aircraft engineer Jack Northrop in 1942. After pitching his “high-speed rocket-powered flying-wing fighter” to the US Army Air Forces, a contract for two prototypes was given in January 1943, with the aim being to develop an aircraft capable of “ramming” enemy bombers from the sky.

Initially, the aircraft was to feature two Aerojet XCALR-2000A-1 liquid-fueled rocket engines, each producing 2,000 pounds of thrust. These ultimately proved unsatisfactory and the decision was made to, instead, install two Westinghouse 19B turbojets.

Testing the unique design

Northrop MX-334 in the wind tunnel at the National Advisory Committee for Aeronautics (NACA) Langley Research Center in Hampton, Virginia. (Photo Credit: NASA Langley / Wikimedia Commons / Public Domain)

The US Army Air Forces contracted Northrop for three gliders to test the design. These were dubbed the MX-324 when referring to the secret aspects of its powerplant and the MX-334 when it was operated as a true glider. The first, MX-334 No. 1, was tested in the wind tunnel at the National Advisory Committee for Aeronautics (NACA) Langley Research Center, and the results led to a vertical stabilizer being added for stability at high speeds.

The No. 2 glider participated in the first flight attempts; it was towed by a Cadillac car for takeoffs, landings and low-level flights. While these proved unsuccessful, subsequent tows with a truck and, later, a Lockheed P-38 Lightning proved more successful.

In early 1944, the No. 2 glider was modified with the Aerojet XCAL-200 rocket. The first flight took place on July 5, with the MX-324 becoming the first American-made, rocket-powered aircraft to fly. After flight testing was finished, the other two gliders were discarded.

Northrop XP-79 specs

Northrop XP-79B. (Photo Credit: USAAF / National Museum of the U.S. Air Force / Wikimedia Commons / Public Domain)

The Northrop XP-79 had an overall length of 13.98 feet, a wingspan of 37.99 feet and a height of 7.58 feet. Its overall design resembled a flying wing, similar to the YB-49, and it featured a welded magnesium monocoque structure, as opposed to the typical riveted aluminum. At the “nose” was a central cockpit, which the pilot operated in a prone position, helping them to withstand more g-forces than they could in a seated position.

There were two air intakes on either side for the two engines. With its two Westinghouse 19B axial-flow turbojets producing 1,150 pounds of thrust each, the XP-79 could hit a maximum speed of 547 MPH and maintain a cruising speed of 480 MPH. It also had a range of 993 miles and a fuel capacity of 300 gallons, allowing for an endurance of almost two and a half hours.

As aforementioned, the XP-79 was developed to “ram” into enemy bombers. To do this without injuring the pilot or damaging the aircraft mid-flight, armored glass mounting was used in the cockpit and armor plating was added to reinforce the wings. When it became clear such a concept wouldn’t succeed, the aircraft was equipped with four Browning M2 machine guns.

A fatal test flight leads to the Northrop XP-79’s cancellation

Northrop XP-79B. (Photo Credit: USAAF / National Museum of the U.S. Air Force / Wikimedia Commons / Public Domain)

The Northrop XP-79B made its first-ever proper flight on September 12, 1945. Concerns over the aircraft’s tires and brakes during taxiing trials at the Muroc Dry Lake (today Rogers Dry Lake) had previously delayed this.

Only 15 minutes into the flight, test pilot Harry Crosby lost control while performing a slow roll. The Xp-79B then began to spiral downward from an altitude of 10,000 feet, flying into the ground. Crosby attempted to bail out, but was hit by part of the aircraft and killed.

Following the crash, the XP-79 was canceled and all work stopped on constructing a second prototype.