Mark 17
The Mark 17 was the first deliverable thermonuclear weapon. This massive bomb weighed 21 tons and could be carried in a B-36 after modifications were made to the bomb bay. Pilots who test-dropped the weapon reported that the plane rose hundreds of feet after the weapon was dropped, as if the bomb released the plane rather than the reverse. The Mk 17/24 Thermonuclear bombs were first stockpiled in April 1954 as Emergency Capability (EC-17) until fuzing and suitable parachute delivery was developed.
At 11 megatons the Romeo shot of 26 March 1954 was the third largest test ever detonated by the United States. The Runt I device in this shot was a proof test of the Mk-17 bomb (which was deployed as the emergency capability EC-17 in a matter of months).
The Mark 17 was the first H-bomb that could be dropped from a plane. Its steel casing was about 3.5 inches thick and weighed almost 21 tons. The MK17 was 24 feet 8 inches long, 61.4 inches in diameter, and weighed between 41,400 and 42,000 lbs.; much of this was casing weight. The MK17 bomb was only four feet shorter than a POLARIS A-1 SLBM, but weighed half again as much. Approx 200 were made. Size wise, the Mk 17 was the largest nuclear weapon ever built by the United States
When the Mk 17 was test-dropped, the pilots said it was as if the bomb had released the aircraft, since suddenly lightened of the heavy weapon the plane would soar hundreds of feet as the pilot’s fought to regain control. In combat a gigantic 64-foot diameter ribbon parachute was designed to slow down or retard the big bomb giving the delivery aircraft time to escape the deadly effects of the thermonuclear explosion.
The yield of the Mk 17 was in the megaton range – a megaton (Mt) being the explosive equivalent to one million tons of TNT. The bomb was at one time referred to as a Mk 17/24 because the same weapon case was used for both of these early weapons. The only differences between the Mk 17 and the Mk 24 were internal.
This was the primary EWO weapon carried by the B-36 fleet during the 1950s. The bomb was carried in the two aft bomb bays, while a smaller 6,000 pound MK6 atomic bomb was carried in one of the forward bomb bays.
