Retired Navy Capt. Gerald Coffee on Thursday helped observe the 40th anniversary of Operation Homecoming, which brought 591 POWs to Hickam Field from Feb. 14 to April 4, 1973. Coffee, a reconnaissance jet pilot, spent seven years in the notorious "Hanoi Hilton" prison. The memorial at Joint Base Pearl Harbor-Hickam marks the spot where Coffee and the others first set foot back on American soil. The anniversary was observed Thursday by the Hickam-based 15th Wing.