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  • This video was made possible by CuriosityStream, sign up for the Nebula bundle deal for just

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  • video that inspired this episode.

  • Earlier this month I posed this question to my twitter followers. Was the P-47 Thunderbolt

  • one of the best planes of World War 2? And 35% of my audience said, no. So, in today's

  • video I am going to explain why I disagree with 35% of my audience.

  • As we will see over the course of this video, the P-47 had it's flaws, but by the time

  • the P-47D-25, easily identified by its distinctive bubble canopy, entered service in the spring

  • of 1944, the P-47, in my opinion, was an excellent plane that was instrumental to the success

  • of the Allied invasion of Europe.

  • The P-47s reputation may have been a victim of its image. It's not sleek and aerodynamic

  • looking like the Spitfire or P-51 Mustang. It lacks the stylish gullwing of the F4U Corsair

  • and has never gained the infamy of the Stuka.

  • The plane is unusually….thicc? Seeing images of it's crew standing next to their planes

  • really demonstrates how huge the fuselage was. The crew of this P-47 clearly agreed.

  • They painted the word chunky onto the engine cowl. But if you are like me, this should

  • indicate to you that there was something unique about the plane, that the designers tried

  • something different. The best way to illustrate this is through a size comparison.

  • This is the P-51 Mustang. It's a streamlined, athletic looking plane...and this is the P-47.

  • You could have literally fit a P-51 inside the P-47 with room to spare. It simply doesn't

  • look the part, but what if I told you it's frame was purpose built to fit one incredibly

  • powerful supercharged engine.

  • Just as its namesake, the A-10 Thunderbolt II, was built around it's gun, it's ancestor

  • was built around it's colossal engine. The massive Pratt and Whitney R-2800 Double Wasp.

  • A two row, 18 cylinder air-cooled radial engine with a massive displacement of 46 litres.

  • [1] The Merlin engine of the Spitfire and P-51 Mustang for comparison, one of the most

  • commonly used Allied engines of WW2, was 27 litres.

  • And this is just the powerplant, the P-47 was also fitted with a supercharger that took

  • up a significant volume of the aft fuselage, and this gave the P-47 some incredible high

  • altitude performance.

  • This shows the basic layout of the engine and supercharger inside the P-47 fuselage.

  • [2] The P-47 had a massive air intake just underneath the engine, big enough for a man

  • to fit in. The air from this intake was not immediately funnelled into the engine, instead

  • it was routed to the back of the plane first. Where it split into two ducts. One flowed

  • into a supercharger impeller, which compressed the air and returned it to the engine carburetor,

  • while the secondary duct flowed into an intercooler to cool the air from the compressor section

  • which had heated up as a result of the compression.

  • Ofcourse, this compressor section needed to be powered. This was done through hot energised

  • exhaust which was collected from the engine through this collection ring in a separate

  • duct system. This air was funnelled to a lower turbine section of the supercharger before

  • the hot exhaust was vented to the atmosphere here.

  • At lower altitudes less of this energised exhaust made it to the supercharger, as there

  • are two gated exhaust nozzles on either side of the plane that gradually closed as the

  • plane climbed in altitude.

  • This ensured the R-2800 double wasp was supplied with plenty of cold compressed air even at

  • 27,000 feet, where other planes could not funnel enough of the oxygen needed to achieve

  • full engine power.

  • This wasn't the only trick the P-47 had up it's sleeve.

  • P-47D-4 variants and onward were fitted with a 30 gallon tank filled with an alcohol water

  • mixture located between the pilot and the engine in the firewall.

  • In times of emergency this mixture could be injected into the engine. This gave short

  • bursts of additional horsepower, taking the engine from it's already massive 2,000 horsepower

  • to 2,300 horsepower.

  • So how does spraying water into an engine increase horsepower? The water isn't fuel

  • and it displaces some air entering the engine surely. Your immediate thought would be that

  • this reduces horsepower. To boot, water is corrosive and incompressible, which could

  • cause some serious damage

  • Water injection increases horsepower in two ways. Both as a result of water's cooling

  • effects. When water is injected into the engine it absorbs heat from the air and engine in

  • the process of evaporating. This increases engine pressure and lowers the temperature

  • of the piston. [3] Colder air is denser, and thus more air/fuel mixture is carried into

  • the piston with each stroke, increasing the energy released in each power stroke. The

  • evaporation also cools hotspots in the engine that can cause pre-ignition of the air-fuel

  • mixture. Meaning the air fuel mixture ignites before the piston is at the bottom of it's

  • compression stroke and thus is working against the power strokes in the other cylinders,

  • lowering the power output of the engine.

  • The limited water supply meant this power boost was saved for emergency use only, but

  • emergencies are the exact time a little boost in horsepower is needed. Whether that is climbing

  • a little faster to regain an altitude advantage after a diving attack, taking off with a little

  • extra weight, or simply speeding away from an aggressor.

  • With all these design features, the P-47 was a fast plane with few planes being able to

  • match it's high altitude performance. Early versions of the P-47 did suffer from poor

  • climb and turning performance. That massive engine added a great deal of weight, and by

  • virtue of the large fuselage needed to hold it, a great deal of parasitic drag too. In

  • order to climb or turn, the engine and wings needed to provide the force necessary to lift

  • the plane to higher altitude or shift it's direction.

  • These characteristics did not affect the P-47s roll rate however, where it excelled thanks

  • to fantastic aileron control. [10] However, in a dog fight being outturned or out climbed

  • was a death sentence.

  • Climb rates were improved for the P-47D-22 and onward with the addition of a new larger

  • propellor, a 4 metre diameter propellor nicknamed the paddle prop. It had a longer chord and

  • distinctive cuffs which helped channel more air into the engine.

  • This new prop made the climb rate disadvantage marginal, surprising German pilots who had

  • become accustomed to pulling up sharply to evade P-47s. [1]

  • So the P-47, wasn't the best out and out fighter. Surely that supercharger gave it

  • excellent high altitude performance, making it the perfect bomber escort. Yes and no,

  • because of another design flaw it's range was lackluster.

  • The huge fuselage and engine made the P-47 a thirsty plane. It's fuel tanks were always

  • going to struggle to feed this hungry engine. The plane could carry 305 gallons in two tanks

  • located around the cockpit. [4] The main L shaped tank located in front of and below

  • the pilot could hold 205 gallons, while the secondary tank located below and behind the

  • pilot could carry an additional 100 gallons.

  • These tanks gave the pilot between an hour and a half and 2 hours of flight time and

  • only just 50 extra miles of range over the spitfire, a notoriously short range fighter.

  • [5]

  • The spitfire was primarily designed as an interceptor to protect British Airspace, the

  • P-47 was not designed for this purpose and it's lack of range frustrated bomber crews

  • who relied on it's protection. The pilot's of the Luftwaffe were perfectly aware of the

  • P-47's range issues and often waited for the pilots to turn for home before launching

  • an attack.

  • All but the earliest production runs of P-47s could carry a drop tank on a belly hardpoint,

  • like this P-47D flying with a 75 gallon drop tank, which would have increased it's range

  • by 180 kilometres. However plumping, hard points, and wing reinforcement to allow for

  • wing mounted drop tanks were added insultingly late with the P-47D-15. [6] This allowed the

  • P-47 to carry 108 gallon drop tanks on each wing, increasing the operational range by

  • 380 kilometres. Allowing P-47s to reach as far as Frankfurt and Hamburg.

  • These tanks of course affect the plane's performance, pushing weight outwards decreases the planes

  • roll rate significantly, but they could be jettisoned if needed during a dog fight. This

  • was not an ideal solution, and the P-51 Mustang was without a doubt a better escort and fighter

  • plane.

  • However, the P-47 shined elsewhere. Those hardpoints were not exclusively designed to

  • carry external fuel tanks, they were designed for weapons and the P-47 could carry an impressive

  • payload. The P-51 Mustang had a max payload of 450

  • kg across it's two wing-mounted hardpoints and had 6 M2 machine guns with 1840 rounds.

  • The P-47 in comparison could carry over twice the weight in bombs at 1,136 kilograms with

  • 4 M2 heavy machine guns in each wing. [7] The guns were staggered like this to allow

  • side loading from each of their 350 round magazines. The P-47 was easily the heaviest

  • hitting single engine fighter of world war 2, and it could take a hit too.

  • The plane was affectionately nicknamedThe Jug”, short for Juggernaut, and for good

  • reason. Durability is a difficult thing to quantify, and it's hard to parse out survivor

  • bias, but just like the A-10, photos of surviving planes tell a story. If you were crash landing

  • in any fighter in WW2, you would want it to be the P-47. There are countless photos of

  • P-47 crash landings where the pilot lived to tell the tale. All that ducting around

  • the pilot provided cushioning from the impact, and the smooth belly of the aircraft, free

  • from air scoops and other protrusions, minimized the risk of turnovers, which could crush and

  • kill the pilot, or simply trap them inside the plane.

  • The P-47 could take a lot of damage and keep flying. The liquid cooled Merlin engines of

  • the P-51 Mustang were not known for their ability to take a hit, but the air cooled

  • R-2800 double wasp radial engines were. The structure of the P-47 wings was incredibly

  • durable and could stay intact with severe damage. The ducting for the supercharger provided

  • some protection from bullets, and did not cause catastrophic failure with a few bullet

  • holes resulting in a drop in supercharger pressure, which at worst required the pilot

  • to drop in altitude and lower power. The fuel tanks under the pilot were self sealing and

  • offered good protection from hits on the belly of the plane and the pilot had two armored

  • plates behind and infront of the cock-pit.

  • So, we have listed the P-47s disadvantages, how they were minimized and it's advantages.

  • What's my rationale for saying it was one of the best planes of world war 2?

  • People who learn their history from video games will bash the P-47 for it's slight

  • disadvantage in dogfighting, which is true enough, but it disregards the brain of the

  • pilot. The P-47 had it's disadvantages in a dogfight, but it's advantages are what

  • the pilots were trained to use and they were trained well. Why engage in a dogfight when

  • you have an altitude and speed advantage. The P-47 was the perfect hit and run fighter.

  • Striking from above, often catching the enemy unaware, and using it's speed advantage

  • to escape.

  • They were most certainly capable of dispatching ME 109s and FW 190s, as proven by countless

  • flight reports from pilots. [8]

  • ME 109s could most certainly out turn a single P-47, but out turning 2 or 3 was an insurmountable

  • challenge, which was the challenge the Luftwaffe were met with as soon as the manufacturing

  • prowess of the United States entered the European Theatre. The P-47 was like the M4 Sherman

  • of the air, perhaps not the best vehicle on paper, but it got the job done and was there

  • when you needed it.

  • It was also the United States Air Force's best fighter bomber. This plane was the warthog

  • of WW2. With the Luftwaffe threat all but vanquished by D-Day, the P-47 truly shined

  • in Normandy. Becoming a feared bird of prey over Europe.

  • The Allies quickly constructed advanced landing grounds in Normandy to create forward operating

  • bases for their air forces, like St. Pierre Du Mont located to the West of Omaha Beach.

  • What was once a farmer's field became fully operational airfield just 12 days after d-day

  • with access roads, fuel dumps, ammo depots and a 1500 metre long track surfaced in steel

  • square mesh track. These advanced landing grounds gave even the shortest range fighter

  • aircraft the ability to loiter in the air over Normandy and push deeper into German

  • territory than