Eighteen A6M2 Zeros of the Tainan Kokutai took off from Lae Airfield to strafe targets at Port Moresby. On the way to the target, one Zero aborted and returned to base.
The 1st Chutai (pilot names unknown).
The 2nd Chutai was led by Tadashi Nakajima, with Hiroyoshi Nishizawa, Jnicchi Sasai, Toshio Ota, Saburo Sakai, Tsuomo Ito and Kaoru Yamaguchi. [This was the only mission when Nishizawa, Sasai and Sakai flew together on the same day over Port Moresby.]
Sixteen Airacobras of the 8th Fighter Group's 36th Fighter Squadron and 35th Fighter Squadron intercepted them, P-39F 41-7122 ditched (pilot rescued) P-39 Airacobra piloted by Brown (damaged). The Japanese claimed six shot down, and the Americans also over claimed. Also, Airacobras from the 35th Fighter Group's 39th Fighter Squadron and 40th Fighter Squadron intercepted.
Over Port Moresby, they found few targets on the ground, as American aircraft were well dispersed, including A-24 dive bombers warned to leave the area. As the Zeros strafed 7-Mile Drome and 12 Mile Drome, two were damaged by 50 caliber machine gun fire from the ground. A6M2 piloted by Kaoru Yamaguchi departed the target and was observed to crash into the foothills of the Owen Stanley Mountains. A6M2 Zero piloted by Tsuomo Ito departed the target alone and force landed in the Owen Stanley Mountains. Later, he was taken prisoner.
The remaining thirteen Zeros returned to Lae Airfield. Two others landed at Salamaua Airfield.
War Diary 1942: page 56
"Moresby raided by nine Zeros. They were driven off the target at the drome and strafed all along the Laloki Valley, as we had long expected."
C.O.I.C. Intelligence Resume to 1100Z/18/5/42
Australia Station - Sightings and Reports 17/5/42
(a) Sightings etc. New Guinea Area 17/5 - [?]
BUNA reported unidentified aircraft, probably 9, flying SW. 0944K KIKODA " large enemy force heading P/M at 0956K/17
(b) RAID 51 PORT MORESBY 0014Z to 0027Z/17 by 9 Zero fighters. Approached from North, came down on NW end 7-Mile drome and 8 P39's and 7 P400's intercepted and prevented further strafing although further attempts were made to strafe Bomana drome and shipping in harbor - .5 A/A Bomana scored shots on 2 Zeros which were seen smoking when going away to NW. .5 A/A TUAGUSA [?] also engaged Zeros attempting to straff shipping in harbour.
1 Zero shot down (confirmed)
1 P39 shot down in BOOTLESS INLET pilot safe. (injured) [P-39F 41-7122 piloted by Bland]
1 P39 forced landed RORONA - pilot safe [P-39 Airacobra piloted by Brown, damaged]
1 P400 " " BEAGLE [?] BAY - pilot safe [?]
Thanks to Edward Rogers for additional information.