To keep the many men and machines in fighting shape during the World War II invasion of France, logistics technicians sure had their work cut out for them. Bomb, bullets, planes and tanks were top priorities, so there was little room for luxury items that'd keep the troops in good spirits while fighting Nazis.
And when a British brewery donated gallons of beer for troops on the front, there was no way to get it to the men by conventional means.
Enter Britain's Royal Air Force.
In the early days after the Normandy invasion of June 1944, British and American troops noticed an acute shortage of adult beverages — namely beer. Many British soldiers complained about watery cider being the only drink available in recently liberated French towns. Luckily for them, the Royal Air Force was on the tap (pun intended) to solve the problem.
With no room for cargo on their small fighter planes, RAF pilots arrived at a novel solution – using drop tanks to transport suds instead of fuel.
The drop tanks of a Spitfire each carried 45 gallons of gas, meaning a plane could transport 90 gallons of extra liquid. When carrying fuel, the tanks were used and then discarded.
For the purposes of ferrying beer, ground crews set about steam cleaning the tanks for their special deliveries. These flights became known as "flying pubs" by the troops they served. A few British breweries, such as Heneger and Constable, donated free beer for the RAF to take to the front. Other units had to pool their funds and buy the beer.
As the desire for refreshment increased in Normandy, the RAF began employing the Hawker Typhoon which could carry even more than the Spitfire. Unfortunately, the Typhoon was often mistaken by inexperienced American pilots as the German Focke-Wulf 190.
According to one British captain, the beer deliveries were attacked twice in one day by U.S. P-47 Thunderbolts. The Typhoon had to jettison its tanks into the English Channel to take evasive action, costing the troops on the ground dearly.
The drop tanks also had a serious disadvantage. While they could carry large amounts of beer, the initial runs still tasted of fuel. Even after the tanks had been used several times and lost their fuel taste, they still imparted a metallic flavor to the beer.
To counter this problem, ground crews developed Modification XXX, a change made to the wing pylons of Spitfire Mk. IXs that allowed them to carry actual kegs of beer.
These kegs, often called 'beer bombs,' were standard wooden kegs with a specially-designed nose cone and attachments for transport under the wing of the Spitfire. Though they carried less beer, it arrived tasting like it just came out of the tap at the pub, chilled by the altitude of the flight over the channel.
To ensure their compatriots remained satisfied, pilots would often return to England for rudimentary maintenance issues or other administrative needs in order to grab another round. As the need for beer increased, all replacement Spitfires and Typhoons being shipped to airfields in France carried 'beer bombs' in their bomb racks to the joy of the thirsty crews manning the airfields.
When the Americans learned of what the British were doing they joined in, even bringing over ice cream for the GIs as well.
As the practice gained popularity, Britain's Custom and Excise Ministry caught wind and tried to shut it down. Thankfully by that time, there were more organized official shipments of beer making it to the troops. However, the enterprising pilots kept up their flights with semi-official permission from higher-ups, they just kept it a better secret.