JoblinTheGoblin
Airman
- 79
- May 13, 2023
I've seen numerous claims on the internet that some Japanese pilots over-tuned their aircraft and, in battle, demonstrated performance beyond official specifications. These claims extend even to early-war Japanese aircraft, including the infamous Zeke and, I believe, the Oscar as well. Supposedly, there exist accounts by pilots, in interviews or otherwise, of aircraft, the Frank most notably, achieving or even exceeding speeds as high as 700kph (434 mph, 377kt), far beyond the usual sub-600kph (372mph, 323kt) and sub-644kph (400mph, 347kt) speeds given for such aircraft. From what I've read on the J-aircraft forums and elsewhere, the Japanese did have small stocks of high-octane fuel, primarily 100 octane. At least some of this fuel was captured from the Allies. This high-octane fuel was, if I remember correctly, reserved for prototype aircraft, but could some of it have been delivered to front-line aircraft? Is there any truth to these claims?
I've also heard claims that there were accounts by American pilots, flying in aircraft like the P-51 over Iwo Jima and elsewhere, of the excelsior performance of late-war aircraft like the Frank, how they were difficult to hit, that it was primarily the inexperience of their pilots that prevented them from being as lethal as they could potentially have been. Certainly, the accounts of Oscar pilots as presented in the book covered in this thread suggest that the Frank, possibly at lower altitudes, was somehow capable of evading the P-51 thanks to its speed, and primarily its speed; dives were said to have been more effective against the Frank compared to the Oscar due to its reduced manoeuvrability. The Frank's relatively lacklustre manoeuvrability was also noted during combat trials with the Seafire, as detailed in a report covered in this video. I wonder if anyone here has any Frank encounter reports on hand, particularly with P-51s, or encounter reports with other late-war Japanese aircraft, for that matter. Such reports could shed further light on the performance of these aircraft, anomalous or otherwise, at least to some degree.
If this article is to be believed, the Homare could handle boost pressures higher than its specified take-off/emergency boost of +500 mmHg (1.66 atm, 49.61 inHg), up to approximately +800 mmHg (2.05 atm, 61.42 inHg), its uppermost limit. Presumably, other Japanese aircraft engines like the Kasei were similarly capable of handling excessive boost pressures. From this other article on the same website, the Frank was recorded as having a top level flight speed of 634-5kph (394mph, 342kt) operating with a boost pressure of +350 mmHg (1.46 atm, 43.70 inHg). How much faster could the Frank have flown with the excessively high +800 mmHg boost? Would its critical altitude be low enough to negate any potential gains in performance? Would any fuel the Japanese possessed in any significant quantity, including their aforementioned stocks of 100 octane gas, be capable of supporting this high boost in engines like the Homare during flight? The Frank certainly would have hardly been capable of evading superior late-war Allied aircraft with the inferior speeds, and, given its good power-to-weight ratio, poor climbing presented in the article.
I've also heard claims that there were accounts by American pilots, flying in aircraft like the P-51 over Iwo Jima and elsewhere, of the excelsior performance of late-war aircraft like the Frank, how they were difficult to hit, that it was primarily the inexperience of their pilots that prevented them from being as lethal as they could potentially have been. Certainly, the accounts of Oscar pilots as presented in the book covered in this thread suggest that the Frank, possibly at lower altitudes, was somehow capable of evading the P-51 thanks to its speed, and primarily its speed; dives were said to have been more effective against the Frank compared to the Oscar due to its reduced manoeuvrability. The Frank's relatively lacklustre manoeuvrability was also noted during combat trials with the Seafire, as detailed in a report covered in this video. I wonder if anyone here has any Frank encounter reports on hand, particularly with P-51s, or encounter reports with other late-war Japanese aircraft, for that matter. Such reports could shed further light on the performance of these aircraft, anomalous or otherwise, at least to some degree.
If this article is to be believed, the Homare could handle boost pressures higher than its specified take-off/emergency boost of +500 mmHg (1.66 atm, 49.61 inHg), up to approximately +800 mmHg (2.05 atm, 61.42 inHg), its uppermost limit. Presumably, other Japanese aircraft engines like the Kasei were similarly capable of handling excessive boost pressures. From this other article on the same website, the Frank was recorded as having a top level flight speed of 634-5kph (394mph, 342kt) operating with a boost pressure of +350 mmHg (1.46 atm, 43.70 inHg). How much faster could the Frank have flown with the excessively high +800 mmHg boost? Would its critical altitude be low enough to negate any potential gains in performance? Would any fuel the Japanese possessed in any significant quantity, including their aforementioned stocks of 100 octane gas, be capable of supporting this high boost in engines like the Homare during flight? The Frank certainly would have hardly been capable of evading superior late-war Allied aircraft with the inferior speeds, and, given its good power-to-weight ratio, poor climbing presented in the article.
