The following kills are known to be credited to him by the VPAF while flying the MiG-21 PFL Fishbed D model:[2][3][4]
30 April 1967, a
USAFF-105F (serial number 59-1726, 354th Tactical Fighter Squadron,
pilot Thorness,
RWO Johnson,
POWs; a second F-105(D) claimed by Do's wingman
Nguyễn Văn Cốc in this same flight);
05 May 1967, an F-105D (pilot Shively, POW, US claims shot down by
AAA);