First Lieutenant Notestein was a pilot for the 549th Bomb Squadron, 385th Bomb Group, Heavy. His B-17 was nicknamed "Piccadilly Queen". It would be on January 29, 1944, his 7th mission, that Notestein and "Piccadilly Queen" were ordered to bomb AAF Station 155 in Frankfurt, Germany at noon. Before they reached their target, anti-aircraft flak had hit the bomber many times, causing it to catch on fire. It was still flying. Halfway between Ludwigshafen and Edenkoben, Germany, "Piccadilly Queen's" tail gunner, Staff Sergeant Carl Huwe, shot down an enemy plane. Notestein congratulated Huwe over interphone. Minutes later Huwe was shot by a 20mm bullet in the chest. He was last heard saying "They got me", over intercom. Immediately after at 11:06 AM, a bullet hit and exploded in the cockpit leaving Notestein, Second Lieutenant Follensbee, and Technical Sergeant Gla Owen with minor injuries. This bullet was said to be shot by Major Walther Dahl. Another 20mm bullet hit Gla Owen in the face as well. Six minutes later, "Piccadilly Queen" took another hit in the right wing which broke off. The B-17 Flying Fortress went into a spin. Notestein rang the alarm bell and ordered the crew to bail, handing his parachute to Gla Owen. Even though the flight controls were shot up, Notestein stayed behind to try and stabilize the bomber enough so the crew could jump. Before the crew could jump though, a German Messerschmitt Bf 109 collided into the waist of the bomber. This was fortunate for some crew members as they were thrown out of the plane and were able to parachute to the surface. Unfortunately, for Staff Sergeants John Moriarty and Clifford Owen, both waist gunners, they were thrown out of the plane without parachutes. The plane split in two and dispersed in air. Finally at 11:17 AM, "Piccadilly Queen" crashed in southern Kaiserslautern, Germany, with Notestein still in the cockpit.

Klaus Frölich, a child at the time, heard a massive explosion above the clouds. That explosion was the German plane hitting Notestein's bomber. As the burning parts of the plane came down, Frölich, being the curious child he was, walked closer to a object already on the ground. That object was one of the crewmembers with an unopened parachute. This was most likely Technical Sergeant Owen. This is because of the other five killed crewmembers, he was the only one last seen with a parachute and killed in action. It was also assumed Owen's parachute never opened after he bailed as he wasn't in the plane when the co-pilot jumped, as stated by Second Lieutenant Markwell. Frölich describes the object as having its head stuck between the pelvic bones. Frölich and his friends later went to the bomber's crash site where he found Notestein in the pilot's seat. Staff Sergeant Huffman III was still in the ball turret. Staff Sergeant Huwe was found in the tail of the bomber.