First Lieutenant Hernandez was the navigator of a B-29A Superfortress Bomber with the 371st Bomber Squadron, 307th Bomber Wing based at Kadena Air Base, Okinawa. On 8 September 1950, while returning from a bombing mission over Korea, his aircraft crashed into the East China Sea five miles north of Okinawa. He was listed as Missing in Action and was presumed dead on 31 December 1953.

Hernandez was awarded the Purple Heart, the Korean Service Medal, the United Nations Service Medal, the National Defense Service Medal, the Korean Presidential Unit Citation and the Republic of Korea War Service Medal.