Nukes vs. Airplanes

Between the F-80 and the F-104, a supersonic pioneer fought the Cold War...in its own way.

  • By Jorge and Karen Escalona
  • Air & Space magazine, July 2008
View More Photos »
$Alt

Lockheed Martin

Photo Gallery (1/2)

As a "penetration fighter," the XF-90 was meant to do it all: destroy ground targets, withstand anti-aircraft fire, outrun enemy fighters, and escort bombers to their targets. It ended up as atomic bomb test fodder.

See more photos from the story

Video Gallery

Test Flying the XF-90

Test Flying the XF-90

Archival film of this rare bird in flight.


Operation Tumbler-Snapper

Operation Tumbler-Snapper

Atomic bombs versus airplanes in the Nevada desert.



(Page 2 of 4)

It fell to Chuck Buzzetti, a research engineer in the flight test organization, to evaluate the strain gauges used to measure the wing loads on the heavy aircraft. “The main I-beam of the F-90 resembled a bridge girder,” says Buzzetti.

Due, in part, to its aluminum skin—four times more stress-resistant than the standard alloy of the day, and a feature that enabled the aircraft to withstand 12 Gs—the single-seat fighter weighed as much as a DC-3, and was almost 71 percent heavier than an F-86, so its Westinghouse engines were seriously underpowered. The team could only hope the airplane would survive its test flight.

“I’ll never forget one flight Tony made on May 17, 1950,” recalls Joiner. “It was one of the times when Kelly [Johnson] was there. The test program was to conduct power-on dives to work up to the so-called sound barrier. We were on the radio with Tony as he made a dive at fairly low altitude. We could see the airplane on the other side of the dry lakebed. It disappeared in the haze. At that moment we heard a tremendous explosion. There is no doubt that both Kelly and I thought that the airplane had augured in. I was afraid that Kelly was going to have a heart attack. Within a very short time Tony called in on the radio. Talk about relief! He had dived the airplane to Mach 1.12 and everything was fine. You have to realize that we hadn’t heard a sonic boom before. I’m not sure about Kelly but there’s a good chance he hadn’t heard one either. Tony went on to exceed the speed of sound a number of times, and the XF-90 handled fine. It certainly experienced no problems structurally.”

Despite the aircraft’s attributes, the need for an all-purpose fighter was declining. “It had become obvious to everyone that this do-everything fighter was not a good idea,” says Joiner. “I guess you could say it was a jack of all trades but master of none.”

In 1950, the Air Force awarded its contract to the McDonnell XF-88A. With the outbreak of the Korean War, however, the Air Force needed combat airplanes in a hurry, and looked to the existing F-80, and the F-86, which was already in production. The exhausted Lockheed team turned to other projects. LeVier would later observe, “Sometimes it is better to chalk an airplane off as experience and go on to something else.”

The company retired the two prototypes to careers as structural test subjects. The first prototype was tested to destruction at the National Advisory Committee for Aeronautics Laboratory in Cleveland. The second XF-90 (along with other aircraft, including a B-45, a B-29, F-47s, and B-17s) was sent to the Nevada Proving Ground for use in a nuclear weapons test. Secured about a half-mile from ground zero, and nose-in to the first two blasts, the XF-90 survived a one-kiloton shot on April 15, 1952, with undamaged wings, but sustained enough dents and cracks—not to mention the buckling of a fuselage fire door—that it would have taken approximately 106 hours to repair. A second, 31-kiloton blast a week later bent the aircraft’s nose. For the third blast, 19 kilotons detonated on May 1, the XF-90 was positioned perpendicular to the shock wave. The blast severed the tail and blew the landing gear from the wing; the main wing structure was buckled and scorched.

The Nevada Test Site later suspended above-ground tests. After a 5.3-kiloton underground blast, in December 1963, the XF-90’s contaminated, cracked, and partially scorched frame was moved to NTS Area 11, where it was used in Broken Arrow exercises in which crews trained for recovery of a downed airplane with a nuclear payload.

The aircraft was officially documented as destroyed— “vaporized, people thought,” says Robert E. Friedrichs, a physical scientist at the National Nuclear Security Administration’s Nevada Site Office. But flying over the test site a few years later, Ernest Joiner saw something unexpected: “Looking down, we could see the XF-90. It appeared to be intact.”

On April 22, 1952, dozens of journalists and approximately 2,000 military personnel watched as a 31-kiloton nuclear bomb exploded above the Nevada Proving Ground. Operation Tumbler-Snapper, as the series of atmospheric tests was called, was designed to evaluate the vulnerability of parked aircraft to an atomic bomb blast. Among the aircraft gathered there was one of the hottest-looking fighters ever built: Lockheed’s XF-90.

The needle-nose fighter followed Lockheed’s F-80 Shooting Star, the first U.S. jet fighter to see action, and was an important precursor to the “missile with a man in it,” the F-104 Starfighter. And though only two were built, the XF-90’s dashing good looks earned it movie-star status throughout the 1950s—far beyond its operational life—attracting readers and advertisers to prominent aviation periodicals and comic books of the time. As a single-engine F-90B, it made a splashy cover for the September 1953 comic book Blackhawk. Thereafter, a generation of young Boomers dazzled by futuristic aviation technology awaited each new adventure of American pilot Blackhawk, his buddy Chuck, and their coalition of international fighter jocks manning a fleet of six sleek F-90Bs in the quest to take down the “Red Tide” thugs of the atomic age.

The F-90 was the first U.S.-built, swept-wing jet to use afterburners as standard equipment and have wingtip fuel tanks and a fully adjustable fin and stabilizers. Fowler flaps and leading-edge slats improved airflow over the wings, making the F-90 one of the pioneers in 35-degree swept-wing technology. In tests, the hot rod exceeded Mach 1 fifteen times.

So how did such a capable aircraft, one that so captured the public’s imagination, become atomic bomb test fodder?


After World War II, the U.S. Army Air Forces needed a “penetration fighter,” capable of escorting bombers to and from their targets. The early jet fighters had been far from perfect, and their notorious fuel consumption decreased their range. In 1945, the AAF issued a request for a fighter with a combat radius of about 900 miles. Competing for the contract against McDonnell’s XP-88A and North American’s XP-86C, Lockheed’s team, headed by Clarence “Kelly” Johnson and Willis Hawkins, went through 65 versions before settling on the swept-wing design of the XP-90. (In 1948, the P designation, for “pursuit,” was changed to F, for “fighter.”)

Johnson pushed the group to produce two twin-engine prototypes, whose appearance inspired the team to coin the nickname Big Broad-Breasted Turkey. “Its front view with the broad fuselage and side inlet ducts gave it the broad-breasted look,” says Jim Beach, the engineer who pioneered the XF-90’s canopy actuation and ejection system. “Jim Pray, the windshield designer, dubbed it a ‘turkey’ due to its wimpy engines.”

Testing of the “wimpy” engines began on the ground at Burbank, California, but the first XF-90 was trucked to the North Base of Muroc Air Force Base, now Edwards Air Force Base, in 1949 for flight testing by Tony LeVier, Lockheed’s chief test pilot.

Lockheed assigned flight test engineer Ernest Joiner to the project. “Very little was known at that time about what happened to an airplane when it exceeded the speed of sound,” Joiner recalls. “There were all kinds of weird ideas that the airplane would be subjected to very high structural loads. This lack of information contributed to the XF-90 being the strongest airplane anyone had ever seen. Of course, the sound barrier had been broken by Chuck Yeager in the X-1 research aircraft in October 1947, but [that didn’t happen] in time to have much influence on the design of the XF-90.”

It fell to Chuck Buzzetti, a research engineer in the flight test organization, to evaluate the strain gauges used to measure the wing loads on the heavy aircraft. “The main I-beam of the F-90 resembled a bridge girder,” says Buzzetti.

Due, in part, to its aluminum skin—four times more stress-resistant than the standard alloy of the day, and a feature that enabled the aircraft to withstand 12 Gs—the single-seat fighter weighed as much as a DC-3, and was almost 71 percent heavier than an F-86, so its Westinghouse engines were seriously underpowered. The team could only hope the airplane would survive its test flight.

“I’ll never forget one flight Tony made on May 17, 1950,” recalls Joiner. “It was one of the times when Kelly [Johnson] was there. The test program was to conduct power-on dives to work up to the so-called sound barrier. We were on the radio with Tony as he made a dive at fairly low altitude. We could see the airplane on the other side of the dry lakebed. It disappeared in the haze. At that moment we heard a tremendous explosion. There is no doubt that both Kelly and I thought that the airplane had augured in. I was afraid that Kelly was going to have a heart attack. Within a very short time Tony called in on the radio. Talk about relief! He had dived the airplane to Mach 1.12 and everything was fine. You have to realize that we hadn’t heard a sonic boom before. I’m not sure about Kelly but there’s a good chance he hadn’t heard one either. Tony went on to exceed the speed of sound a number of times, and the XF-90 handled fine. It certainly experienced no problems structurally.”

Despite the aircraft’s attributes, the need for an all-purpose fighter was declining. “It had become obvious to everyone that this do-everything fighter was not a good idea,” says Joiner. “I guess you could say it was a jack of all trades but master of none.”

In 1950, the Air Force awarded its contract to the McDonnell XF-88A. With the outbreak of the Korean War, however, the Air Force needed combat airplanes in a hurry, and looked to the existing F-80, and the F-86, which was already in production. The exhausted Lockheed team turned to other projects. LeVier would later observe, “Sometimes it is better to chalk an airplane off as experience and go on to something else.”

The company retired the two prototypes to careers as structural test subjects. The first prototype was tested to destruction at the National Advisory Committee for Aeronautics Laboratory in Cleveland. The second XF-90 (along with other aircraft, including a B-45, a B-29, F-47s, and B-17s) was sent to the Nevada Proving Ground for use in a nuclear weapons test. Secured about a half-mile from ground zero, and nose-in to the first two blasts, the XF-90 survived a one-kiloton shot on April 15, 1952, with undamaged wings, but sustained enough dents and cracks—not to mention the buckling of a fuselage fire door—that it would have taken approximately 106 hours to repair. A second, 31-kiloton blast a week later bent the aircraft’s nose. For the third blast, 19 kilotons detonated on May 1, the XF-90 was positioned perpendicular to the shock wave. The blast severed the tail and blew the landing gear from the wing; the main wing structure was buckled and scorched.

The Nevada Test Site later suspended above-ground tests. After a 5.3-kiloton underground blast, in December 1963, the XF-90’s contaminated, cracked, and partially scorched frame was moved to NTS Area 11, where it was used in Broken Arrow exercises in which crews trained for recovery of a downed airplane with a nuclear payload.

The aircraft was officially documented as destroyed— “vaporized, people thought,” says Robert E. Friedrichs, a physical scientist at the National Nuclear Security Administration’s Nevada Site Office. But flying over the test site a few years later, Ernest Joiner saw something unexpected: “Looking down, we could see the XF-90. It appeared to be intact.”

Friedrichs recognized the fighter’s historic significance. “There were some things about that airplane that I thought were phenomenal,” says Friedrichs. “The fact that the aircraft survived at all is a story that needed to be shared.”

When Friedrichs served as a scientist at the Nevada Test Site, he got a first-hand look at the remains of the airplane as it sat on a dry lakebed over several decades. “Since only two were built and one was destroyed, in the late 1980s I got the process started of getting this aircraft preserved for presentation in a museum,” he says. For 13 years Friedrichs forged through bureaucratic snags: He assessed the aircraft’s historic value, contacted museum curators, organized funding, and found contractors to retrieve and decontaminate the airplane after five decades of radioactive decay.

In 2001, Friedrichs found a home for the XF-90 prototype: the National Museum of the U.S. Air Force, near Dayton, Ohio. The museum’s director, retired Major General Charles D. Metcalf, recognized the important role the aircraft played in the beginning of the cold war as an experiment in early atmospheric testing of atomic bombs. “[The XF-90] had a lot of firsts,” he says, adding that the fighter will be used in an exhibition on “the people and events during the very inception of the cold war.”

Although the sleek fighter never made it into production, its participation in three atmospheric atomic bomb tests helped in waging the cold war. In a 1990 letter to the Nevada Division of Historic Preservation supporting the XF-90’s conservation, Donald Elle of the Department of Energy

noted: “Information derived from [the Tumbler-Snapper project] continues to be used in aircraft design and operational deployment today.”

Friedrichs met with radiation programs director James Seals and Fluid Tech, Inc. to figure out how to deconstruct, survey, and decontaminate each piece of the aircraft. Although Fluid Tech had experience in all types of contamination control, this was the first time the company would clean an aircraft.

Workers found the fuselage inhabited by a thriving colony of white-tail antelope squirrels. Because of the possibility the animals were carrying Hantavirus, Seals used a combination of bleach and sandblast to eradicate 40 years’ worth of nest debris. His crew, sweltering in full protective gear in the desert heat and carrying radiation detectors, scoured every surface, penetrating the smallest crevices to eradicate plutonium residue. During the summer, the crew disassembled and decontaminated the aircraft at night. “By midday it’s too hot,” Seals says of the desert, “even for the snakes.” Temperatures plummeted in the winter. Despite the extremes, the crew members completed the job within a year.

Along the way, they made a surprising discovery. The original Westinghouse engines had survived. “We’d never taken apart a jet engine before, but when we pulled them out, the turbines still turned,” says Seals. “You could push a turbine fin and spin those engines real easy.” 

In 2003, a C-5 transport flew the decontaminated XF-90 parts from the Nevada Test Site to Wright-Patterson Air Force Base. It will take a year to reassemble the aircraft, says restoration division chief Roger Deere, who will prepare the airplane for exhibition. (While the XF-90 awaits restoration, visitors can see the fighter by taking a special behind-the-scenes tour.)

Although one aircraft on the Nevada Test Site, a B-17 bomber, was rebuilt and flown out, Friedrichs was hesitant to see someone try to fully restore the XF-90. “When you only have one left, you really don’t want to take the chance of flying it and possibly losing it,” he says. Instead, says Deere, “The exhibit will tell the story that the XF-90 has been through three nuclear blasts.” He admits, “It would be a major chore to restore it to a good, decent-looking airplane.” Instead, says Friedrichs, the public will see the XF-90 “exactly as it sat out here in the desert for half a century.”  


Single Page « Previous 1 2 3 4 Next »


 
Comments (14)

Very informative article. Although I have studied the aircraft from a variety of sources, I learned a few more tidbits of the story of this bird. As a volunteer at the National Museum of the United States Air Force I am building a 1/48th scale model of the XF-90 to be displayed along with the actual aircraft. The purpose of the model is to depict the aircraft as it looked in it's flying trim.

The model's construction is completed and is awaiting the application of the natural metal finish. The video offers angles that I have not seen before and will aid me in presenting an accurate portrayal of the finish of the aircraft. In building a realistic model, it it much more difficult to replicate a natural metal finish than it is a painted finish.

Would it be possible for me to obtain a copy of the video for my research? It would be for my use only and only for the purpose of presenting an accurate model to the viewing public.

For you information, I was a tour guide at Garber and a Docent at the new NASM building in 1975 - 1977 time frame. I left only due to military transfer. Also, the scratchbuilt 1/32nd scale SR-71 on display in the Looking At Earth gallery was built by me and delivered in 1984.

I await your response.



Mark E. Young, Jr.
MSgt, USAF (Ret)
Member, International Plastic Modelers Society

myoung14@woh.rr.com

Posted by Mark E. Young, Jr. on May 13,2008 | 08:59 PM

Very interesting, informative and well-written article. I hope someday to find myself viewing her remains at Wright Patterson. Thanks for bringing her story to life in these pages.

Posted by Paul Reese on May 16,2008 | 09:02 PM

Mark,
Glad you found the article informative. I found some of the video footage back in 2000 from the NARA (National Archives and Record Administration) at College Park, Md. My records show: "NARA Stock Footage # 001396 CR #: 342 USAF 14340" Good luck with your project and look forward to seeing your SR-71 at the museum.
Jorge

Posted by Jorge Escalona on May 17,2008 | 11:30 AM

Very cool story about this aircraft and its history. I have some knowledge of the aircraft but have never known the full story and in particular the story of the plane after it was no longer a flight test article. What a great story and a very good read!!

Posted by Ricardo Traven on May 18,2008 | 08:57 AM

Jorge:

Great article!

I assume you have a turbine-powered R/C version of the aircraft in your shop?

I want to see it fly!

Regards to Karen.

Wes

Posted by Wes De Cou on May 19,2008 | 11:48 AM

A most interesting, well researched article of historical value. The insights provided into the development and significance of the XF-90 are commendable.

Having spent some thirty years on a combination of active and reserve duty with the U.S.Air Force and having participated as member of a disaster control team at an actual Broken Arrow site I found the article particularly helpful.

My congratulations to the authors, Jorge and Karen Escalona.

Posted by Joseph Ramirez on May 19,2008 | 12:15 PM

Jorge: You did a great job on the XF-90 article, after knowing you all these years it came as no surprise. For all of you who do not know Jorge I can tell you he has a passion for this aircraft. Jorge has been an RC jet pilot for as long as RC jets have been around. I can remember way back when Jorge showed me his first prototype of the RC jet XF-90. He flew it many times, crashed it more times than it flew (one crash was my fault) and never gave up. Each time he learned a bit more about his aircraft, he made changes and perfected the design. After many years of hard work he finally reached the point where the RC version performed with perfection. Last I heard he was working on a larger version. Hope to see the big XF-90 sometime in the near future.

Posted by Albert Araujo on May 20,2008 | 11:19 AM

I was really pleased to see the article on the XF-90 finally published so the general public could know the whole story on this remarkable aircraft. Jorge and Karen Escalona were incredibly through in their research, double checking their information every step of the way. Their desire to tell the whole story is to be commended.

The folks at Air and Space were equally through in validating and double-checking the details of this remarkable story. The result was a very tight article that included all of the salient pieces of the aircraft's history.

Thank you all for your outstanding efforts!

Posted by Robert Friedrichs on May 26,2008 | 01:47 PM

I very much enjoyed the article and was pleased and surprised to see the reference to the use of the F-90B in the Blackhawk comics. I created the idea of the modified, single-engine F-90B to explain the differences between the real aircraft and the way it was drawn in the comics when I was building my Blackhawk Comics website back in the early '90s. I'm glad to see that the concept has become accepted enough to be referenced in a magazine of Air & Space's caliber. For the complete story of the Blackhawks' use of the Lockheed F-90, see my website:

http://ourworlds.topcities.com/blackhawk/models/mod_f90b.htm

Posted by Dan Thompson on June 19,2008 | 12:36 PM

8 YEAGER WAS NOT THE FIRST TO BREAK THE SOUND BARRIER..


Be nice if you got your fact right,,

Regards,,lee

Posted by lee koukes on July 19,2008 | 03:24 PM

I very much enjoyed your article. I remember the Blackhawk issue you used for illustration. It is interesting to note the first Blackhawk plane used for the comic was the Grumman XF5F Skyrocket which also only existed as two prototype aircraft.

Is there any footage of the Grumman XF5F Skyrocket in flight. I purchased a book with many photos but have never found any footage. Would it be possible to check your sources for such footage?

Posted by David Chapman on July 24,2008 | 01:18 AM

Lee, if it's this guy you're talking about:

"After Willy Messerschmitt's death, the former Me 262 pilot Hans Guido Mutke claimed to be the first person to break the sound barrier on 9 April 1945 in a Me 262, in a "straight-down" 90° dive. This claim is disputed because it is only based on Mutke's memory of the incident, which recalls effects that other Me 262 pilots have observed below the speed of sound and a high airspeed indicator reading, but no altitude reading, which would be required to determine the actual speed. Furthermore, the pitot tube used to measure airspeed in aircraft can give falsely elevated readings as the pressure builds up inside the tube at high speeds. Finally, the Me 262 wing had only a slight sweep incorporated for trim (center of gravity) reasons and likely would have suffered structural failure due to divergence at high transonic speeds."

That's a very questionable dispute to be so harsh in critism about, don't you think? Everyone and their dog accepts the fact that Yeager's was the first verified successful attempt during level sustained flight, let it go... It's kind of like asking someone "how fast did you go?" and they answer "pretty damn fast!" I'm sure Mutke was indeed going pretty damn fast. We know exactly how fast Yeager went.

Posted by john on November 16,2008 | 11:56 AM

I just found this article about the U.S.A.F. XF90. I was stationed at (Muroc) Edwards Air Force Base in California from 1949 to 1952.
I was assigned to the motor pool and took the tail section of the XF90 to ground zero at the Nevada Atomic Test Sight. Lyons Van Line took the wings on one trailer and the fusilage on another trailer. I stayed and helped assemble the XF90 back together.

Edward R. Somers

Posted by Edward Somers on January 28,2013 | 02:28 PM

Thank you for posting the short film footage of the XF-90. As your article pointed out, the airplane was the very essence of the jet fighter in the late 1950's when I started building models. To see her fly even 60 years later is truly wonderful. I look forward to the day I can go see her in the flesh, er, aluminum.

Posted by Richard Girard on May 28,2013 | 09:01 PM

Post a Comment


Name: (required)

Email: (required)

Comment:

Comments are moderated, and will not appear until Smithsonian.com has approved them. Smithsonian reserves the right not to post any comments that are unlawful, threatening, offensive, defamatory, invasive of a person's privacy, inappropriate, confidential or proprietary, political messages, product endorsements, or other content that might otherwise violate any laws or policies.



Advertisement


Advertisement


Follow Us

Snapshot

Grover Rover

This robot will be studying our own planet.

Reader Scrapbook

Discovery's Tail-Cone Fitting

Check out our scrapbook of readers' aviation and space pictures. Then add your own.

Smithsonian Store

Smithsonian Journeys