After completion of B-29 training Hap and a crew of 11, called "Rover Boys Express", spent time in Lincoln, Nebraska, then Herington, KS where they received their own B-29. Orders were to fly their new B-29 west alone to Mather Field, CA, then across the Pacific alone to John Rogers Field, Hawaii, then to Kwajalein Island; then to Saipan where the 73^rd Wing Base was located; they were to fly combat missions to bomb and destroy Japanese mainland targets.

They flew missions to Iwo Jima, Nagoya, Kobe/Akashi in December 1944 and January 1945 before they were shot down on their fourth mission – target #357 Nakajima Aircraft Factory, Tokyo. They were eastbound at 32000 ft. passing Mt. Fuji when shot down over Tokyo by a Japanese Twin Engine Toryu (Nick) Fighter that came in from 1 0’clock high. Three engines were on fire. They had to parachute into Tokyo when the fighter blew out the nose, the 70^o+temperature in their pressurized B-29 dropped instantly to –58^o below zero.

Hap fell free from 27,000 ft. to approximately 3,000 ft. before opening his chute and landing in N.E. Tokyo. He was set upon immediately by civilians; and severe beatings followed. Mr. Halloran was near death when Japanese soldiers (MP's from Kempei Lao Secret Service Torture Prison) seized him from civilians and took him to Kempei Tai Torture Main Prison in Tokyo adjacent the moat at the north edge of the Imperial Palace grounds. Hap spent 67 days in solitary confinement in a cold, dark cage. Beatings and brutal interrogations followed. Hap lived through the March 10, 1945 fire raid on Tokyo were over 100,000 were killed by B-29s bombing from 0100 to 0400 a.m. The heat, smoke and firestorm were absolutely terrifying.