Three photo today from a vintage, December 1944, magazine featuring a Nakajima Ki-43 "Hayabusa" standing next to a Nakajima Ki-44 "Shoki" and a Mitsubishi Ki-46. The "Hayabusa" has the engine mount area panels removed offering a rare view of this area but note also the propeller and the spinner area. All the aircraft most unusually belong to the Utsunomiya Army School even though their markings are not visible in the photos.
Small quiz: what model is the "Hayabusa" in the photo?
Thank you all for your answers to the small quiz. Here's an illustration by master artist Watanabe Rikyu, (from No. 235, August 1976 issue of the defunct magazine Koku Janaru - Aviation Journal) illustrating the "Hayabusa" variants. In FAOW #65 there are more sub-types like "early production Model 2 Ko early" and "late production Model 2 Ko early" but I believe the illustration below is a handy, quick, basic recognition guide.
Top left: Model 1, top right: Model 2 Ko early
Middle left: Model 2 Ko later model, middle right: Model 2 Otsu
Bottom right: Model 2 Kai, bottom left: Model 3
So, I would say the "Hayabusa" in the photos is a "Model 2 Ko early".
Answering the question by David S about the correct pronunciation and writing of the word "Ko".
The correct Japanese pronunciation is very similar to this:
with no L in the end. Speakers of most European languages (Greek, Spanish, French, Italian, German...) and generally those with a knowledge of Latin have no problem to identify the sound although it should be a little longer than a simple "KO".
For the issues regarding the transliteration of Japanese words in the Latin alphabet, check here:
Simply put, there is no "correct" way to write the kanji 甲 in Latin. "Ko", "Kou", "Koh" or "Kō" are all possible and "correct". As you have probably noticed this blog prefers the first way with the exception of "Ohka".