SAR-March-AFB
Recruit
- 3
- Sep 12, 2025
If you've explored old bombing ranges it's usually easy to recognize World War II-era munitions since they're mostly sand-filled 100 pound practice bombs, small cast iron MK-23 practice bombs, or 20mm and 50 caliber shells and clips. This however wasn't the case when I arrived at one of two large targets at a historic bombing range north of Wendover Utah.
That morning I struggled against a fierce 35-degree headwind in order to reach a 40-foot wide crater: one of the last remaining vestiges in what was at the time an enormous 91,000 acre bombing range. The range featured two 400-foot wide targets with miles-long guidance markers that helped pilots and bombadiers aboard high-flying B-17s, B-24s, and B-29 bombers line up on them. According to a report by ProPublica, the range had a fortified underground observation bunker, and four concrete foundations that may have been used as camera stations. By comparison the Salton Sea Test Base - which also served as a high-elevation bombing range, had eleven camera stations that captured the aeroballistic characteristics of atomic bomb shapes as they fell from specially-modified "Silverplate" B-29s flying at 30,000 feet.
Looking down into the crater I was surprised that there were no rusty practice bombs, no MK-23's, no 50 caliber shells or clips. Except for the massive crater there was no evidence whatsoever that this target had at one time been pummeled by B-17, B-24, and B-29 squadrons which had taken off from Wendover Airfield on thousands of bombing practice missions.
What I found instead were neat little piles of artifacts that had been conscientiously collected by previous visitors. These appeared to be from more modern munitions: thin aluminum heat shielding (like what you might find surrounding a jet engine), MIL‑Spec electrical connectors, dozens of riveted steel brackets, riveted steel with flat U.S. Army green paint on one side, white fibrous insulating material (possibly asbestos), shiny pieces of titanium (which showed no corrosion whatsoever), a cast aluminum lever assembly with the words INC. ALT., and several strange 1-inch thick cast metal fragments that looked like metal on the surface but were composed of a granular alloy. As I moved away from the crater I found more material that matched what the previous visitors had already collected. I was frozen solid and after an hour I returned to the car with a single souvenir: one of the one-inch thick cast metal fragments, shown in the last attached photo.
Two years went by until a random email from Dave Trojan revealed that he and a friend had explored the same two targets on that bombing range. Dave and his friend had found the same mysterious artifacts that I had, and after Dave shared his sharp "forensic" style photographs we began to understand where they originated.
Our first big break was Dave's revelation that one of his photographs showed what appeared to be the remains of a chronometer, and another showed gold-plated electrical components. I began entering a series of queries into my AI app, (Perplexity). Over a period of days the answers to our riddle became clear: We'd found the remains of a pumpkin bomb that had been filled with high explosive.
In 1945 the 509th Composite Group trained with two kinds of mockups, commonly called pumpkins. Both weighed 10,000 pounds like the actual Fat Man but one was filled with concrete, while the other - which was painted orange, was filled with high-explosive. The high explosive version often contained a chronometer for detonation purposes, and gold-plated electrical contacts that could survive the high levels of radiation commonly found inside the actual Fat Man bomb.
Interesing AI responses to my questions
1. Were chronometers typically found in practice bombs used to train aircrews at Wendover Airfield?
No, chronometers (associated with timing fuzes) were not typically found in practice bombs. However the 509th Composite Group flew missions dropping "pumpkin bombs," which were high-explosive bombs similar in size, weight, and ballistics to the "Fat Man" atomic bomb. These missions included testing special fusing and timing components, that simulated actual nuclear strike conditions in order to perfect weapon delivery techniques. The use of timed or special fuzes allowed realistic training for bomb release and evasive maneuvers after bomb drop, crucial for the crews' survival and mission success.
2. Why would the U.S. Army Corps of Engineers find radioactive contamination at this historic bombing range? (as reported in ProPublica)
The Army Corps of Engineers likely found radioactive material at one of Wendover Airfield's bombing ranges because Wendover was a critical training and testing site for the atomic bomb program during World War II. Wendover Airfield was the training ground for the 509th Composite Group, the unit responsible for delivering the atomic bombs "Little Boy" and "Fat Man." At Wendover, crews practiced bomb drops using "pumpkin bombs," which were the same size, shape, and weight as the actual atomic bombs. These practice devices were sometimes filled with concrete or conventional explosives, but the site was also involved in testing atomic bomb components and weaponization activities linked to the Manhattan Project. This historical use likely left behind radioactive contamination at the bombing ranges.
That morning I struggled against a fierce 35-degree headwind in order to reach a 40-foot wide crater: one of the last remaining vestiges in what was at the time an enormous 91,000 acre bombing range. The range featured two 400-foot wide targets with miles-long guidance markers that helped pilots and bombadiers aboard high-flying B-17s, B-24s, and B-29 bombers line up on them. According to a report by ProPublica, the range had a fortified underground observation bunker, and four concrete foundations that may have been used as camera stations. By comparison the Salton Sea Test Base - which also served as a high-elevation bombing range, had eleven camera stations that captured the aeroballistic characteristics of atomic bomb shapes as they fell from specially-modified "Silverplate" B-29s flying at 30,000 feet.
Looking down into the crater I was surprised that there were no rusty practice bombs, no MK-23's, no 50 caliber shells or clips. Except for the massive crater there was no evidence whatsoever that this target had at one time been pummeled by B-17, B-24, and B-29 squadrons which had taken off from Wendover Airfield on thousands of bombing practice missions.
What I found instead were neat little piles of artifacts that had been conscientiously collected by previous visitors. These appeared to be from more modern munitions: thin aluminum heat shielding (like what you might find surrounding a jet engine), MIL‑Spec electrical connectors, dozens of riveted steel brackets, riveted steel with flat U.S. Army green paint on one side, white fibrous insulating material (possibly asbestos), shiny pieces of titanium (which showed no corrosion whatsoever), a cast aluminum lever assembly with the words INC. ALT., and several strange 1-inch thick cast metal fragments that looked like metal on the surface but were composed of a granular alloy. As I moved away from the crater I found more material that matched what the previous visitors had already collected. I was frozen solid and after an hour I returned to the car with a single souvenir: one of the one-inch thick cast metal fragments, shown in the last attached photo.
Two years went by until a random email from Dave Trojan revealed that he and a friend had explored the same two targets on that bombing range. Dave and his friend had found the same mysterious artifacts that I had, and after Dave shared his sharp "forensic" style photographs we began to understand where they originated.
Our first big break was Dave's revelation that one of his photographs showed what appeared to be the remains of a chronometer, and another showed gold-plated electrical components. I began entering a series of queries into my AI app, (Perplexity). Over a period of days the answers to our riddle became clear: We'd found the remains of a pumpkin bomb that had been filled with high explosive.
In 1945 the 509th Composite Group trained with two kinds of mockups, commonly called pumpkins. Both weighed 10,000 pounds like the actual Fat Man but one was filled with concrete, while the other - which was painted orange, was filled with high-explosive. The high explosive version often contained a chronometer for detonation purposes, and gold-plated electrical contacts that could survive the high levels of radiation commonly found inside the actual Fat Man bomb.
Interesing AI responses to my questions
1. Were chronometers typically found in practice bombs used to train aircrews at Wendover Airfield?
No, chronometers (associated with timing fuzes) were not typically found in practice bombs. However the 509th Composite Group flew missions dropping "pumpkin bombs," which were high-explosive bombs similar in size, weight, and ballistics to the "Fat Man" atomic bomb. These missions included testing special fusing and timing components, that simulated actual nuclear strike conditions in order to perfect weapon delivery techniques. The use of timed or special fuzes allowed realistic training for bomb release and evasive maneuvers after bomb drop, crucial for the crews' survival and mission success.
2. Why would the U.S. Army Corps of Engineers find radioactive contamination at this historic bombing range? (as reported in ProPublica)
The Army Corps of Engineers likely found radioactive material at one of Wendover Airfield's bombing ranges because Wendover was a critical training and testing site for the atomic bomb program during World War II. Wendover Airfield was the training ground for the 509th Composite Group, the unit responsible for delivering the atomic bombs "Little Boy" and "Fat Man." At Wendover, crews practiced bomb drops using "pumpkin bombs," which were the same size, shape, and weight as the actual atomic bombs. These practice devices were sometimes filled with concrete or conventional explosives, but the site was also involved in testing atomic bomb components and weaponization activities linked to the Manhattan Project. This historical use likely left behind radioactive contamination at the bombing ranges.