Here's What You Need To Remember: The Czechs planned on using their stock of Daimler Benz 605 engines intended for use in 109 aircraft. However, a factory fire destroyed the engines, forcing the Czechs to find an alternative. They settled on tapping a stockpile of Jumo 211F engines and propellers used by Nazi Heinkel-111 twin-engine bombers. Needless to say, the 211F wasn’t designed to be a fighter engine — and caused endless problems when fitted to the 109's airframe. Not only were the engines underpowered, but the 109’s original nose-hub cannon was incompatible with it, so the Czechs instead strapped MG 151 cannons under the wings using World War II-era Rüstsatz VI add-on kits. These worsened the S-199’s flight performance.

When Israel declared independence from British colonial rule in May 1948, it immediately went to war with the neighboring Arab states. One of the first weapons Israel acquired was a fighter plane designed by a country that had sought the extinction of the Jewish people.

The German Messerschmitt Bf.109 — later re-designated Me.109 — was the most advanced fighter plane of its time when it first saw combat in 1937 in the Spanish Civil War. Flown by German pilots in support of General Franco’s Nationalists, Bf. 109s secured air superiority over Spain and allowed Fascist bombers to terror bomb cities nearly unopposed.

Recommended: 5 Reasons No Nation Wants to Go to War with Israel

The Bf.109E model was upgraded with 20-millimeter cannons and a new Daimler Benz 601 engine that increased its speed to 354 miles per hour. It swept its opponents from the skies in the invasion of Poland and the Battle of France.

Recommended: 5 Worst Generals in U.S. History

Only when it met large numbers of Royal Air Force Spitfires in the Battle of Britain did it meet its match — resulting in the Nazi war machine’s first major defeat.

While superior fighter aircraft began entering service on all sides by 1942, Nazi Germany continued upgrading and producing 109s until the end of the war. Much of this production took place in heavily industrialized Czechoslovakia, which had been annexed by Germany in 1938. After the defeat of Nazi Germany, the Czechs decided to reopen production by making their own version of the 109, the Avia S-199.

Recommended: Could the Battleship Make a Comeback? 

The Czechs planned on using their stock of Daimler Benz 605 engines intended for use in 109 aircraft. However, a factory fire destroyed the engines, forcing the Czechs to find an alternative. They settled on tapping a stockpile of Jumo 211F engines and propellers used by Nazi Heinkel-111 twin-engine bombers.

Needless to say, the 211F wasn’t designed to be a fighter engine — and caused endless problems when fitted to the 109's airframe. Not only were the engines underpowered, but the 109’s original nose-hub cannon was incompatible with it, so the Czechs instead strapped MG 151 cannons under the wings using World War II-era Rüstsatz VI add-on kits. These worsened the S-199’s flight performance.

The Czechs produced 532 S-199s, which served in the Czech air force for 10 years under the unaffectionate nickname mezek — “mule” — because of their difficult handling characteristics.

War in Palestine:

In the wake of violent anti-Semitic pogroms in Tsarist Russia during the 1880s, European Jews had begun immigrating to Palestine as part of the Zionist movement, which promoted Jewish nationalism.

They joined a local population of Middle Eastern Mizrahi Jews that had lived alongside Arab Muslims and Christians for centuries.

The growing Jewish population led to increasing tensions with local Arab communities, and many Jews and Arabs began to see themselves as being in a zero-sum competition for control of the territory. Palestine at the time was under British colonial rule, which clumsily attempted to pacify both populations, satisfying neither.

As violent clashes erupted, Jewish groups began forming militias. Haganah, the largest group, was led by David Ben-Gurion. There was also the more hardline Irgun under Menachem Begin, and the violent extremist Lehi or “Stern Gang.”

After World War II, these groups launched a guerilla war against colonial rule that led the United Kingdom to begin withdrawing in 1947 after a deadly attack on the King David Hotel. A United Nations resolution calling for separate Jewish and Arab states cleared the way for Ben-Gurion to declare the creation of the state of Israel on May 14, 1948.

Fighting between Jews and Arabs for control of Palestine had already begun well before then.

Britain and France had been decolonizing its other holdings in the Middle East, too, and the newly independent Arab states of Egypt, Transjordan, Iraq and Syria intervened against Israeli forces, which they viewed as illegitimate.

Egypt in particular had inherited a lot of military equipment from the British, and soon Egyptian Spitfires were strafing Israeli-held airfields, while C-47 transports converted into bombers began bombing Tel Aviv.

The leaders of the newly formed Israeli Defense Force, drawn out of Haganah’s ranks, scrambled to put together an air force even before the declaration of statehood.

Haganah already operated an assortment of light civilian planes such as Piper Cubs in its Sherut Avir — “air service” — which flew reconnaissance as well as bombing missions. The pilots held bombs and grenades on their laps and threw them out the side of the cockpit. Clearly, that wasn’t going to cut it much longer.

But Israeli agents had difficulty purchasing military equipment because of an arms embargo. Finally, Otto Felix found a Czech arms dealer willing to sell Avia S-199s at the then-exorbitant rate of $180,000 each, equivalent to $1.8 million today. The price included equipment, ammunition, delivery, and flying lessons for the Israeli pilots, many of whom had only civilian flying experience.

The first order for 10 S-199s was followed by another for 15. When the Israelis subsequently received an offer to purchase far more capable P-47 Thunderbolts at a lower price, they turned it down.

The new air force also lacked qualified pilots and mechanics, so it assembled a rag-tag group of volunteers, adventurers and low-paid mercenaries known asMachal or Machalniks.

Of the 609 personnel that served in the Israeli air force in its first war, 181 were Israeli-born, 182 came from the United States, 80 were South African and around 50 each hailed from Canada and the United Kingdom. The remainder came from at least a dozen other countries. Around four-fifths were Jewish.

On May 6, 1948, two of these volunteers and eight Haganah pilots left for the Czech Republic to begin training on the S-199s.

Four Broken Aircraft Save Tel Aviv:

On May 18, an Egyptian C-47 dropped bombs on Tel Aviv’s central bus terminal, killing 42 people and wounding more than 100.

When the Israeli pilots learned of the attack, they demanded to return to Israel early. Their Czech instructors objected that the volunteers hadn’t even received basic combat training, and only the experienced pilots had any chance of operating the aircraft safely. But the volunteers got their way and headed back to the Middle East.

Plans to ferry the S-199s directly became impossible because of the arms embargo. Instead, technicians dismantled the S-199s. Each was shipped over in two separate flights by enormous long-range C-46 Commando transport aircraft. These flew first to Corsica and from there to Ekron — now Tel Nof Air Base — in Operation Balak, which began on May 20.

In an omen of things to come, the first S-199 was lost on May 23 when its C-46 transport crashed attempting to land in the fog, the dismantled fuselage sliding forward and killing navigator Moshe Rosenbaum. On other occasions, aircraft carrying the 199s were impounded and their crew jailed at various airports for their violation of the arms embargo.

It wasn’t until noon on May 29 that the first S-199s were assembled and in functioning order under the newly-christened 101 Squadron. The appellation “Messerschmitt” for the knock-off aircraft was shortened to Messrs — which also means “knife” in Hebrew.

By then, an Egyptian column of around 2,300 men drawn from the 2nd Brigade mounted in hundreds of trucks was heading toward Tel Aviv, accompanied by armored cars and 10 Matilda and Mark VI tanks. The force stopped near Ashdod, also called Isdud, delayed by a destroyed bridge only 30 kilometers away from the Israeli capital. If it completed repairs to the bridge, the column was poised to capture Tel Aviv the following morning.

Without even a single test flight, the four operational Avias were dispatched directly into combat. The pilots included Ezer Weizman and Mordechai “Modi” Alon — both combat veterans that had served in the British Royal Air Force — plus Lou Lenart, a Pennsylvania Jew with experience flying for the U.S. Marines over Okinawa and Eddie Cohen, who had flown for the South African air force. Each fighter was armed with two small 154-pound bombs.

Upon spotting the Egyptian vehicles, the four S-199s swooped down on the column as 40-millimeter anti-aircraft shells tore up the sky around them. Releasing their bombs, the fighters made three passes, machine guns chattering and cannons barking — but only briefly, because three of the four aircraft’s cannons immediately jammed.

Cohen’s Messr, likely struck by flak, crashed in flames close to the air base of Hatzor. Alon’s airbrakes malfunctioned while returning to base and a wingtip plowed into the ground while landing.