Exit Strategy

Target: Soviet weapons plant. Mission: Low-altitude bombing. Payload: Nuclear. Problem: Getting back.

Air & Space Magazine

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The second type of release was dubbed the “over the shoulder” maneuver. The attacker flew directly over the target and pulled up into a loop, and as the fighter approached the top of the loop, the LABS automatically released the bomb. After release, the pilot continued the loop as the bomb kept climbing. Well before the bomb reached the apex of its climb, the attacker started back down, rolled upright, and headed back in the opposite direction to escape the blast. The loop over the target made the fighter very vulnerable to close-in defenses, but as long as the target could be seen, the fighter could approach it from any angle, so the method was more flexible tactically than the basic toss.

SAC chose the over-the-shoulder maneuver as the preferred means of delivery, with the toss method an alternative if useable landmarks were available. In January 1953, just three months after the tests began, SAC’s fighters officially became part of the strategic force assigned to strike targets in the Soviet Union. Beginning in August 1953, SAC regularly deployed its nuclear-capable F-84s to Europe, refueling en route, and by 1955 it had built this force to over 550 fighters organized into six wings.

But throughout the early 1950s SAC still considered the Boeing B-47 bomber its primary nuclear weapons delivery aircraft. When it entered operational service, its six jet engines and thin swept wings gave it speed and high-altitude capabilities that enabled it to outrun any fighter in the world. By early 1954, though, it was clear that it was only a matter of time before Soviet surface-to-air missiles and MiGs with heat-seeking air-to-air missiles would shut the B-47 out of the high-altitude environment. The bombers would need new tactics to reach their targets. Fortunately, the B-47 had not only high-altitude performance and speed but also excellent maneuverability.

Lieutenant Colonel Doug Nelson of SAC devised the low-level penetration and toss tactic for the B-47 and reportedly startled the SAC staff when he briefed them on the technique. Nonetheless, in early August 1956, SAC asked Boeing to look into the matter, and Dick Taylor was chosen as the company’s test pilot for the project.

After practicing with barrel rolls, Taylor first tried the half-loop, half-roll of the Cuban Eight in the big jet bomber in October 1956. He remembers, “Forty seconds—that’s the time it took to put the B-47 through the half-loop and half-roll. But it seemed like an eternity. For those 40 seconds, I could see nothing but blue sky from the pilot’s seat. After what seemed like hours, I was certainly relieved to see a horizon again. It proved for the first time that a medium bomber, the B-47, had the stability, power, and maneuverability necessary for the toss-bombing tactic.”

Boeing assured SAC that the maneuver, properly flown within the 3-G structural limit, was safe. The next area of concern was the stress of low-level rough air hammering the B-47; its slim, flexible, 116-foot-span wings were considered especially vulnerable. Air Force test crews began flying low-level missions, but during the last phase of testing one of the bombers crashed soon after takeoff. No evidence linked low-level flying to the crash, and after a brief halt the tests continued.

The B-47s proceeded to subject the LABS system to weapons delivery testing, flying the toss maneuver first at minimum weight, then increasing the weight until the last run was at the airplane’s maximum gross weight, 130,000 pounds. In June 1955, a B-47 tossed a 6,000-pound dummy nuclear weapon from a 2.6-G pull-up into a half Cuban Eight, and later tossed an 8,850-pound dummy bomb using the same maneuver. The maneuvers proved easy to perform, and the LABS functioned well. By December 1955, SAC was sufficiently satisfied with the tests to assign three B-47 wings to initiate a low-level-flying and LABS training program called Hairclipper.

The maneuver was “either a bomber pilot’s dream or nightmare,” recalls Sigmund “Alex” Alexander, former president of the B-47 Association, and the crews initially viewed the new tactic with some apprehension. Stewart Frasier, a B-47 bombardier/navigator stationed at Schilling Air Force Base in Kansas, remembers first hearing about it when he and his squadron returned from temporary duty in England. “They announced we had a new bombing plan,” he recalls. “Then they showed us a short film of the B-47 LABS maneuver. We were surprised, to say the least, and there was a lot of concern among the crews. The wing commander heard about this concern, and a couple of days later he ordered all the air crews to assemble near the runway at high noon. He flew down the runway low and fast and then pulled up, over and down into a [half] Cuban Eight to demonstrate it could be done and the wings wouldn’t break.”

B-47 pilot Fred Lange flew a number of LABS training missions from MacDill Air Force Base in Florida. He recalls that the first LABS maneuver he flew with an instructor scared him “because the airspeed going over the top was very slow just before starting the half-roll. In the maneuver, the main thing I tried to do was to lock my knees and not work the rudder pedals to keep the aircraft lined up on a straight line and make a perfect maneuver. I was afraid that the rudder might fail—it was the weakest control surface on the B-47. [But] it just didn’t matter whether we flew a perfect maneuver. I got used to it, and the real fun part of the missions was doing aileron rolls on the way to the bombing range.”

In an actual operation, the B-47 approached the target at very low level while the navigator/bombardier located the target on his radar, computed the pull-up range, and put the solution into the pilot’s LABS timer. At the point where the maneuver was computed to begin, a light on the pilot’s LABS instrument came on and the pilot followed the needles into a 2.5-G pull-up. When the bomb released automatically, the pilot reduced back pressure on the control yoke to keep the B-47 right on the edge of a stall buffet as the bomber went over the top upside down at 85 knots, pulling a third of a G or less and flying on thrust alone. Once the aircraft had come out of the top of the maneuver and was diving, the pilot rolled upright as the copilot called off airspeed to make sure the aircraft did not exceed 400 knots in the dive—any faster and the B-47 suffered aileron reversal, a condition in which a deflection of the aileron tended to flex the wing in the opposite direction and roll the airplane the wrong way.

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