The US and the British continued to build piston planes but they were not, for the most part, planes that had been in production in the middle of 1944.
A few contracts were run out to use up some parts but 1946/47 production used engines not available in 1944/45. Compare F4U-5 to F4U-1D for example.
I would note that the Russians spent a lot of time trying to develop high altitude engines and fighters but were hampered by both fuel and materials, so that few made it into service. German capability to put high flying aircraft (bombers and recon planes) over Russian cities, production centers, transport hubs declined as the war went on making the production of high flying interceptors less of a priority. Not that the Russians didn't want their own in order to reduce dependency on the west. Let's not mention the the high altitude interceptors provided under lend lease.

Or count lend lease aircraft in the types operated by the Russians or the operational flexibility they gave them.
A couple of fairly obvious points.
The Yak 3 was a low altitude, short range air superiority fighter variant of the larger Yak family. It still had a ceiling of 35,000 feet so it wasn't quite the submarine some people imply, and it was also used for ground attack so it's not the 'special snowflake' others imply either. But it was specialized, somewhat for that specific job - shoot down German fighters over the Front. But in the "Yak Family" they also had Yak 1B, Yak 7B, Yak 9K (CAS), Yak 9D (long range), Yak 9U (high speed - 435 mph - / high altitude) etc.
Though the Soviets did have some problems initially developing engines in the early parts of the war, the narrative or Trope that they were still using 1100 hp Hispano Suiza variants even late in the war is false. The VK 107 in the Yak-9U may have had it's serious issues but it generated 1,600 hp. Depending on the variant, the Shvestov ASh-82 (as seen on the La 5) generated 1,850 hp at Sea level and 1,450 at 15,000 feet.
Needless to say all countries faced problems with their engines. The superb merlin had the infamous carbeurator flood cutout with negative G. The Allison V-1710 had the infamous altitude performance ceiling limitations we have discussed so much in here. Even the DB engines had some issues.
You may have "problems" understanding how the Yak 3 performed as it did, as you have mentioned before many times with many other aircraft in threads here that I have been part of, but this really doesn't mean anything. If you really think the numbers are off on several of the famous aircraft that we discuss in here then write a book and source your references. In the mean time Occam's Razor tells me it's far more likely that you are simply leaving something out in your calculations.
Your repeatedly demonstrated lack of imagination in discussions like this in several threads makes this seem much more likely to me. If you start with an assumption and try to find data to fit, you are always going to be a bit perplexed whenever you circle back around to the Historical record and compare your theories to it.
Recon is important, I agree. The Soviets had their own high altitude planes starting with the MiG 3 (which performed well at high altitude even though it lacked capability down low) and high alt versions of the Pe-2R / Pe-3. So it's not like they couldn't manage it. And sure long range recon was an important thing, high flying Ju 86P's, Fw 189s were a problem for the allies in general. Luckily for the Russians they did not have to contend with Ki-46 or Mosquitoes. The Germans certainly went out of their way to shoot down Tac-R planes too, often successfully. But recon was not the same level of importance to the overall war effort that front line fighters were, if only because recon planes often lived or died based on the fighters escorting or chasing them.
The Spitfire came in to the Russian Front originally in the form of the Spit V in 1943. The Soviets were careful with it and did a work-up, but it just didn't perform that well during a period of intensive air combat. The Spit IX which came later was assigned to PVO units where it's main mission was not, in fact, to intercept German Ju-86P or Fw 189s, but rather to stop the occasional Operational level large scale German bombing raid of Ju 88s, He 111s and so on, which had done some serious damage on a few occasions to Soviet production and infrastructure assets in 1941-1943. So I think you are barking up the wrong tree there. The Spit IX was given the job of protecting C3I and factories and leadership. Just like later model P-40s and MiG 3s earlier in the war.
The long and short of it is, the Spit just didn't match the needs of the Theater well enough to be used on the Front Line. Of course they found a use for it, and no doubt an important one, but that can be said of many aircraft in many Theaters that didn't "make the team" for the front line Air Superiority contest. My point being that while clearly a great fighter, the merits of the Spitfire were not universally suited to all Theaters.
None of what I am saying is controversial, I am just pointing out that the quality of a given aircraft in WW2 (to be specific) is a
combination of the traits of the aircraft with the conditions in the Theater and the training and maintenance. Suggesting that the Yak 3 was one of the best fighters of the war is also not controversial in general, in spite of what some people in this forum might think.
By the way, to correct yet another (accidental or otherwise) mischaracterization of what I actually said, I never suggested the P-51 wasn't a great fighter, I just said it wasn't my personal favorite because it came rather late. The same can indeed be said for the Yak 3, Ta-152 or Griffin Engined Spitfires. I like the early to mid-war fighters for the most part which is just a matter of personal preference. But the P-51 is without a doubt one of the best fighters of WW2.
My personal top 10 WW2 "Day Fighter" list, for the record:
- A6M Zero
- Spitfire (Early to mid war variants)
- Yak family (Yak 1, 7, 9 and 3)
- F4U Corsair
- Fw 190A
- La 5 family (5, 5 FN, and 7)
- Bf 109 (Early to mid-war variants)
- P-51 B,C,D
- F4F
- Ki-43 II
Each plane on that list makes the cut for different reasons and I freely admit - this is not a scientific list (how could it be). It's just my opinion. And unlike perhaps some people
I can distinguish between facts and my own personal preferences.
In a top 20 list I'd add the Italian '5 Series' fighters (Reggianne, Macchi, and Fiat), the P-47, P-38, P-40, P-36, MC 202 & 200, Hurricane, Typhoon, Beaufighter, D.520 and Ki-61. Roughly in that order.
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