What is a Flak Jacket?

A flak jacket is a protective garment designed to worn over the torso, keeping the delicate internal organs and ribcage safe from harm on the battlefield. When well maintained, a flak jacket can protect the wearer from bullets, shrapnel, and other projectiles, except at very close range. An alternate spelling for the garment is flack jacket, with both spellings technically being considered correct. Flak jackets have largely been replaced by lightweight body armor, but they played a very important role in warfare for a portion of the twentieth century.

The garment was originally developed for members of the Royal Airforce by the Wilkinson Sword Company. Airmen were at risk of severe injury and death from Fliegerabwehrkanone, exploding shells fired from German anti-aircraft guns operated by ground-based military personnel. The shells were colloquially known as “flak,” and they could do severe damage to the unprotected torsos of pilots and crew as well as their aircraft.

Many people are familiar with the slang term “taking a lot of flak,” which is directly related to the German shells. On nights of heavy shelling, flak could make flying virtually impossible and highly dangerous. The sense of being overwhelmed by people from all sides firing shells transferred into the civilian world by way of many veterans. Unfortunately, a flak jacket to protect from metaphorical flak has not yet been developed.

To address the issue of literal flak, the Wilkinson Sword Company developed the flak jacket, a garment made from heavyweight material lined with metal plates. A flak jacket could also take the form of a flak vest, leaving the arms free for a better range of motion. The jackets proved to be useful, but extremely bulky. Other Allied troops adopted flak jackets for the crews of their aircraft, and ground based soldiers used them as protective wear as well. Many soldiers were saved from death and serious injury by their flak jackets during the Second World War, along with conflicts around the world afterwards. For many nations, a flak jacket was standard issue for soldiers, along with other basic supplies.

The widespread adoption of Kevlar® and more lightweight protective plate materials led to the production of sturdy but much lighter body armor. The term “flak jacket” is sometimes used to refer to modern body armor, which is made by an assortment of companies. The steel plates and bulky materials of the old fashioned flak jacket, however, are not in use on the modern battlefield, although many veterans saved their flak jackets to commemorate their experiences.