U.S. Navy Lighter-Than-Air (LTA)
World War II
Noting the Axis submarine buildup, six copies of the only available modern prototype – the K-2- were put into production as WWII began in Europe. Two bases to be equipped with modern large steel hangars were laid out in South Weymouth, Mass., and Elizabeth City, N.C. Only a half-dozen K-type airships, all without submarine detection equipment, were available after Pearl Harbor. They formed the basis for NAS Lakehurst, New Jersey’s ZP-12, the first airship squadron in the Atlantic. A ragtag band of commandeered Goodyear advertising blimps and former Army airships formed the first West Coast squadron, Moffett Field’s ZP-32.
Few in number but spread along several States’ coasts, the 425,000 ft3 of helium K-ships were repeatedly noted by German U-boats. The K-6’s depth charge attack on surfacing sub U-94 in March 1942 was the first air ASW action on the American coast, after which the U-boat turned for home.
Radar and magnetic detection sets were fitted to the K-types slowly coming off the new production line, as both new bases formed squadrons, ZP-11 and ZP-14.
Innovative airshipmen overcame scarcity to perform a variety of services from convoy escort to location of lost airplanes. At the height of Germany’s “battle of tonnage,” U-boats recorded several airship attacks; Navy Intelligence credited three with probable damage. On 3 JUN 42 the patrolling K-3’s crew witnessed a distant torpedoing; attacking, K-3 immobilized the U-432, preventing further attacks on a convoy.
Shocked by torpedoed ship losses, Congress authorized “200 airships of any type” in June, 1942. Nonetheless saddled with the lowest priority for materials, K-type production slowly ramped up to outfit ten major airship bases built up around the American coasts.
Seventeen new hangars, constructed of timber to preserve steel, were built at the existing bases and Richmond, Florida; Brunswick, Georgia; Hitchcock, Texas; Houma, Louisiana; Tillamook, Oregon, and Santa Ana, California. K-ships were first flown to, then later erected on the West Coast for Squadrons ZP-31 and ZP-33. Operating in a variety of weather and conditions, fatal accidents were few. (One commandeered blimp, L-8, even returned without its crew, a mystery to this day.)
New Squadrons ZP-15, ZP-21, ZP-22, and ZP-23 were formed. Though never stronger than a few dozen aloft in the Atlantic any given moment in 1943 as their new bases were completed, airships were logged by U-boats, recording several attacks. No merchantmen were sunk when an airship was in escort. Only one submariner was bold enough to launch a torpedo attack (unsuccessfully) after spotting “active airship protection.” Counter-attacking in that 25 AUG 43 encounter, the K-34 drove off the U-107. Only the K-74 was shot down as it damaged the surfaced U-134, after which the sub turned for home.
Patrol Groups became Wings as K-ships were deployed in the Caribbean and Central America, also protecting both ends of the Panama Canal. Just as the German Enigma codes were broken, SECNAV Knox publicly declined vectoring airships directly to intel-derived submarine locations. Codebreaking steered convoys around U-boats, further reducing escorting blimp’s likelihood of encountering a U-boat.
Never equipped with radio detection-homing gear, blimps achieved inadvertent success keeping radar-detecting U-boats immobilized underwater simply by performing long duration patrols while using their radar. Goodyear’s first modern pressure airship, the M-type, had to be designed and constructed out of K-ship assembly line allotments. The 625,000 ft3 M-1 had greatly improved performance, but materials allotted airship production were never raised above Priority Four. Allotments ran out at 135 K-types and only 4 M-types.
Deployed to the Mediterranean in 1944, ZP-14 crews made the first non-rigid airship crossings of the Atlantic via Newfoundland and the Azores, then via Bermuda and the Azores in 1945. The Africa Squadron established a nighttime magnetic anomaly detection (MAD) barrier across the Straits of Gibraltar, which no U-boat penetrated. The LTA sailors earned praise for their de-mining work across the central Mediterranean. Establishing a maintenance base in southern France, the former German Zeppelin hangars at Cuers were commandeered. Stateside, resourceful airshipmen developed and employed airborne rescue equipment, demonstrated carrier operations and refined radio navigation. Establishing records for continuous years of all-weather operations, the dependable K-type airships’ safety record was the envy of airplane ASW as they performed some two dozen types of additional tasks. Topside rigging and engine changes were completed as the ships swung on the mast at remote sites.
In response to the new threat of radio-silent U-boats approaching to launch V-1 cruise missiles, K-ships were finally equipped with advanced ASW equipment very late in the war. K-ship crews met the last U-boat onslaught with sono-bouys and the homing torpedo. Evidence suggests the K-72 used them successfully against a sub on 18 APR 45. The final hits on the last U-boat in American waters were delivered in May by K-ships following surface units damaging themselves with their own depth charges. Though all but the one combat was classified for 50 years, WWII established the record of the airship as the submarine’s only natural enemy.
See also Airship Utility Squadron ZJ-1