Old 666 was a Boeing B-17E Flying Fortress heavy bomber, serial number 41-2666, assigned to the United States Army Air Forces (USAAF) 19th and 43rd Bombardment Groups in 1942–1943.

It is notable for being the aircraft piloted by Lt. (then Captain) Jay Zeamer Jr. on the 16 June 1943 mission which earned him and 2nd Lt. Joseph Sarnoski each a Medal of Honor, and all other members of the aircrew the Distinguished Service Cross.

[7] Besides significantly reducing its overall weight by 2,000 pounds (910 kg), including stripping out unnecessary structure, cartridge belts, and ammunition feed equipment, the aircrew also replaced the four aging engines with new ones, as Zeamer wanted a fast aircraft.

[8] Another AP article, dated 30 May 1943, reported Zeamer and his crew strafing Japanese searchlights while flying over Wewak, New Guinea, at an altitude of 900 feet (270 m).

Standard bombing missions were flown by the other Flying Fortresses, reserving "666"/ Lucy and its specialty camera array for photo and mapping work.

[15][16] Twice before taking off at 4:00 a.m., 16 June, Zeamer rejected orders to add to the mission a reconnaissance of Buka airdrome, located off Bougainville's northern tip.

Contemporary accounts indicate the aircrew counting around 50 enemy aircraft on either side of the airfield, with crew statements given in support of Zeamer's Medal of Honor reporting 17 or 18 Japanese fighters either taxiing or taking off, as Old 666 flew over the island.

Shortly before its completion, ineffectual passes from below were followed by a handful of Zeros enclosing the B-17 from below in a coordinated attack, two approaching from the rear and three fanned across the front.

The combination left Zeamer unable to execute his usual defensive air tactic of turning inside the line of fire of enemy aircraft attacking from the front.

[18] This first attack proved fatal for bombardier 2nd Lt. Joseph Sarnoski, who was mortally wounded by a 20mm shell hit, which also badly injured the navigator, 1st Lt. Ruby Johnston.

[20][7] Having finished the mapping run and now needing oxygen, Zeamer dove Old 666 down to about 10,000 feet (3,000 m), estimating his altitude from a change in manifold pressure, as the altimeter had been destroyed.

Correctly assuming that the forward machine guns were now inoperable, the Japanese pilots began lining up on both sides of Old 666 to circle around, one by one in turn, to strafe from the front.

Able piloted Old 666 on a dead-reckoning return heading, determined by the badly wounded Zeamer, while the unscathed substitute copilot, Lt. John T. Britton, took stock of the damage to the aircrew and their aircraft.

Radio operator Vaughan, while nursing his neck wound, calculated a heading for Dobodura, an Allied airfield on the eastern coast of Papua, New Guinea, for an emergency landing (it was not expected that Zeamer could survive a return flight over the Owen Stanley Range to Port Moresby).

Britton, having returned to his seat for the balance of the flight, landed at Dobodura without working flaps or brakes, requiring him to carefully ground loop Old 666 near the end of the 6,000-foot (1,800 m) runway.

[28] The aging and much-abused Pacific Flying Fortresses were increasingly difficult to maintain, and the longer range of the B-24 made it more practical in a theater of war defined by the vast distances to targets.