This is how WW2 Marines made ice cream at 30,000 feet
Every job has its unexpected perks. Even being a Marine Corps aviator in World War II had some unexpected benefits. This is because Marines make do, as the saying goes, and are used to making the most out of whatever Uncle Sam provides them to get the mission done. They will even make miracles happen when it's not part of the mission. That's just what Marines do, even when it comes to ice cream.
Everyone loves ice cream and I state that firm belief as someone who has been lactose intolerant his entire life. Marines these days give the Air Force a lot of smack for (almost) always having sweet treats present wherever there's an Air Force dining facility. But let's be real, after a few days, weeks, or however long being deprived of even the simplest luxury, a bit of ice cream goes a long way. Marine aviators in the Pacific Theater thought so, too.
The United States captured the island of Peleliu from Imperial Japan after more than two months of hard fighting toward the end of 1944. Marines on Peleliu were within striking distance of the enemy, but since there was no real threat at the time, they were not on combat patrols or supporting operations elsewhere in the theater. The Marines were getting bored and if you've ever made it past basic training in any branch of the military, you know there are few things more inventive or more dangerous than bored Marines.
One squadron commander, J. Hunter Reinburg, figured he could probably raise morale among his men if he could fix one of his F4U Corsair fighter-bombers to become a high-altitude ice cream maker. It wouldn't be that hard. His crews cut the ends off a drop tank, created a side access panel, and strung a .50-caliber ammo can in the panel. He instructed the mess sergeant to fill the ammo can with canned milk and cocoa powder. All he had to do was get it cold enough to freeze – no problem for a high-altitude fighter.
There was something to Reinburg's thinking. Ice cream has long been a staple of American morale. During the years of Prohibition, ice cream and soda jerks replaced bar nuts and bartenders for many Americans. Ice creams were marketed toward helping people cope with suffering during the Great Depression. When World War II broke out, other countries banned ice cream to enforce sugar rations — but not the United States. Americans loved the sweet treat so much the U.S. military even planned to build a floating ice cream factory and tow it into the Pacific Theater.
For Marines stranded on a hot island with no fresh food and no refrigeration, high-altitude ice cream was a great idea.
Army Air Corps bombers had been making the sweet treat in the same way for years, flying at frigid high altitudes while the hum and vibrations from the engine churned the milk and sugar into frozen ice cream. For the Marines, the first run was a disaster. Reinburg circled the island at 33,000 feet for 35 minutes. When he landed, the mixture was still liquid. But Marines don't give up so easily.
The second run saw ammo cans bolted onto the underside of wings to keep the ice cream base far from the hot engines. The mixture froze, but didn't have the creamy texture the men wanted so badly. The third run was the most inventive of all. This time Marines rigged the ammo cans themselves with propellers which turned a screw inside the ammo cans, churning the ice cream as it froze.
This time the ice cream was perfect. The only hitch was they forgot to let the Operations Officer, a Colonel, have a ration of ice cream.