A Syrian Democratic Forces (SDF) female fighter's braid is pictured while she is carrying her weapon in Tal Samin village, north of Raqqa city, Syria November 19, 2016. (Photo by Rodi Said/Reuters)

A U.S. Army B-24 Liberator Bomber is hailed by a ground crewman as it takes off over a line of shark- nosed fighter planes at an advanced base in China on a mission on October 10, 1943, to bomb Japanese installations. (Photo by AP Photo)

Tajammu Al-Ezza brigade fighters react while firing a Grad shell towards forces of Syria's President Bashar Al-Assad stationed in Salhab village, Hama countryside, May 7, 2015. (Photo by Mohamad Bayoush/Reuters)

A French Air Force Mirage 2000 fighter jet takes off during the close air support (CAS) exercise Serpentex 2016 hosted by France in the Mediterranean island of Corsica, at Solenzara air base, March 17, 2016. Serpentex is an annual exercise that involves joint terminal attack controllers (JTACs) from 12 countries from March 7 to March 25, 2016. (Photo by Charles Platiau/Reuters)

Ayesha Farooq, 26, Pakistan's only female war-ready fighter pilot watches an airforce jet about to take off at Mushaf base in Sargodha, north Pakistan June 7, 2013. Farooq, from Punjab province's historic city of Bahawalpur, is one of 19 women who have become pilots in the Pakistan Air Force over the last decade – there are five other female fighter pilots, but they have yet to take the final tests to qualify for combat. A growing number of women have joined Pakistan's defence forces in recent years as attitudes towards women change. (Photo by Zohra Bensemra/Reuters)

Fighters from Germany take up position before competing in the Medieval Combat World Championship at Malbork Castle, northern Poland, April 30, 2015. Medieval combat is a full contact sport that revives the foot based tournament fighting of medieval Europe. Countries fight in refereed matches where the objective is to get the opposing team to the floor. There are also duels with polearms, swords and shields where the number of hits landed are scored. The fighters, both male and female, wear heavy armours and weapons, mostly replicas of authentic pieces, and fight following the knights code of conduct. According to organizers, 25 nations from 6 continents are taking part in the Championships, which started on April 30 and will go on until May 3. (Photo by Kacper Pempel/Reuters)

In this aerial image, debris of the Japanese Imperial Navy fighter A6M “Zero” is seen in the field on August 29, 2016 in Babeldaob Island, Palau. The war was opened up 75 years ago by Imperial Japan against the allied forces, including the United States, by the Pearl Harbour attack on December 7, 1941, claimed more than 2 million lives until Japan's surrender in 1945. (Photo by The Asahi Shimbun via Getty Images)