How The Focke-Wulf Fw 190 A-4 Almost turned the tide

In 1942, Germany introduced the Focke-Wulf 190 A-4 Variant. While this variant is now mostly forgotten, do you know that it became so close to being a game-changer?

The 190 A-4

The 190 A-4 is essentially an earlier A-3 but with an enhanced radio and some other upgrades. You can set it apart because it uses a shorter nose (like most A3s.) However, it has a triangular antenna mounted on the vertical stabilizer. The A4 is the only model that combines these two features.

Another major change is the addition of the MW50 aka methanol water injection. This gave the plane a 400 hp advantage over other models. It has the best power-to-weight ratios of fighter planes of its time.

What Went Wrong?

Why can’t the Germans keep using this technology to keep bumping up the power increments so that it can stay competitive with the power increases seen in Allied fighters?

Well, it appears that the problem was the sudden drop in temperature during the compression stroke which causes cracks in the cylinder heads. There’s a theory in aviation that rapid cooling of an aircraft cylinder head can lead to cracking. Over time, these cracks will spread and eventually cause engine failure.

The FW-109’s radial engine is closely covered and it’s supercharged so it can get pretty hot. Methanol injection has a powerful cooling effect and contrary to popular belief, most cooling takes place in the cylinder and combustion chamber when the piston is on the compression stroke.

What if It Worked Out?

Had the MW-50 worked out, the 190 A4 with 2100 hp in its airframe would have been a fantastic dogfighter. With a power-to-weight ratio of 248 hp per pound, the plane’s acceleration climb as well as its ability to maneuver in the vertical would have made it a very tough opponent.

For instance, the Spitfire Mk. 9, probably the best dogfighter on the Western Front, was behind the A4 with .23 hp per pound. Had the Luftwaffe got the MW-50 to work in the Anton and had they used it in all the plane’s versions and not just the ground attack variants, the Luftwaffe would have been better equipped to handle the US Army Air Force and other escorts.