According to Tainan Flying Group kôdôchôsho:
On 24 Jan. 1942 the 5 other pilots were LT Akira WAKAO, PO2 Susumu ISHIHARA, WO Senri ISOZAKI, PO1 Toyo’o SAKAI, Seaman 1C Haruo FUJIBAYASHI,
Nishiyama was transferred to the Sixth Flying Group after April 1942. From November 1942 6th Flying Group was changed its name to 204 Flying Group.
PO3 Nishiyama’s score according to kôdôchôshos:
> Tainan Flying Group
10 Dec. 1941: shot down 1 enemy aircraft.
13 Dec. 1941: destroyed 12 aircraft on the ground (shared with 15 pilots including him).
24 Jan. 1942: shot down 1 fighter alone; destroyed 3 twin-engine bombers on the ground (shared with 6 pilots incl. him).
3 Feb. 1942: shot down 1 Buffalo (shared with LTJG SASAI and PO2 ISHIHARA).
20 Feb. 1942: destroyed 5 B-17s and 1 twin-engine aircraft on the ground (shared with 9 pilots incl. him).
22 Feb. 1942: destroyed 12 aircraft on the ground (shared with 6 pilots incl. him).
23 Feb. 1942: shot down 1 enemy flying boat.
25 Feb. 1942: shot down 8 P-40s (incl. 4 probables) shared with 6 pilots incl. him.
27 Feb. 1942: shot down 1 four-engine flying boat and 1 twin-engine flying boat (probable), both shared with 9 pilots incl. him; destroyed 10 aircraft on the ground shared with 9 pilots.
2 Mar. 1942: destroyed 1 float-plane, 1 four-engine flying boat and 1 two-engine flying boat on the water shared with 9 pilots incl. him.
> The 6th Flying Group
28 Sep. 1942: shot down 1 F4F.
>The 204 Flying Group
14 Nov. 1942: shot down 2 SBDs (incl. 1 probable) shared with 6 pilots incl. him.
2 Jan. 1943: shot down 1 F4F shared with PO3 Hikoharu KAWADA.
15 Jan. 1943: shot down 2 F4Fs, and 1 P-39(probable).
23 Jan. 1943: shot down 5 F4Fs (incl.1 probable) shared with 15 pilots incl. him.
25 Jan. 1943: shot down 1 F4F shared with 22 pilots incl. him.
1 Feb. 1943: shot down 4 B-17s shared with 12 pilots incl. him.
4 Feb. 1943: shot down 4 enemy aircraft with 12 pilots incl. him.
3 Mar. 1943: MIA during a convoy escort mission.
His total air victories: 8.75, plobable: 2.01, and destroyed on the surface: 5.41
Source: “Tainankû hikôkitai kôdôchôsho (Tainan Flying Group preliminary combat reports)” Japan Center for Asian Historical Records <
https://www.jacar.archives.go.jp/aj/meta/detail-en >, reference code: C08051601300, 14th, 15th, 29th, 30th images; C08051601600, 24th, 25th images; C08051601900, 10th, 14th images; C08051602000, 30th, 31st images; C08051602100, 1st, 2nd, 11th, 30th, 31st, 45th, 46th images; C08051602200, 11th, 12th images.
“6 kû hikôkitai kôdôchôsho (6th Flying Group preliminary combat reports)”, reference code: C08051629000, 5th, 6th images.
“204 kû hikôkitai kôdôchôsho (204 Flying Group preliminary combat reports)”, reference code: C08051653800, 18th, 19th images; C08051654000, 4th, 5th images; C08051654100, 1st, 2nd, 27th, 28th, 34th, 35th images; C08051654400, 2nd, 3rd, 9th, 10th, 48th, 49th images.