Blimps At War

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At 0430 hours on January 15, 1942, the moon had already set, leaving the world without shadows. The 12-man crew of blimp K-3 , Airship Patrol Squadron 12, left the makeshift operations room at Lakehurst Naval Air Station, in New Jersey, and climbed up the narrow ladder into the blimp’s gondola, commonly known as the “car.” Their orders were to fly east into the night and be off the coast by dawn. It was their first war patrol.

The blimp’s two 550-horsepower engines roared, and it began slowly taxiing down the runway. On each side, a line of sailors, fingers stiff from the cold, clung to the car’s railing or held lines dangling from the giant gasbag. At the command “Up ship!” all lines were cast loose. The single taxi wheel bounced off the tarmac, and the blimp rose into the crisp air at a 40-degree angle, then leveled off at a cruising altitude of 600 feet. The roar of its engines became a distant drone; then that, too, vanished.

Over the coastline the crew tried to settle into their assigned duties: donning yellow life jackets, test-firing the machine gun, and performing other routine tasks. But this flight was different from the training exercises that had preceded it. This time it was for real. Every man aboard the blimp, from the command pilot down to the lowest rating, hoped that beginner’s luck might grant them the rare chance to be heroes. They knew, however, that it was much more likely that they would spend the day flying at low altitude and slow speed over one of the world’s most strategically crucial sea-lanes, scanning the enormous blue world of the Atlantic for signs of an elusive enemy.

Thirty minutes into the mission, a line of light gray insinuated itself into the darkness, parting sea from sky. The early light showed a dark speck on the horizon. It grew rapidly as it closed in on the blimp.

“A plane,” the skipper announced from his forward lookout station, lowering his binoculars. “A Navy scout.” The moment of anxiety passed. The two-engine plane zoomed by, circled the blimp twice, dipped its wings, then flew in a northeasterly direction. The meaning of the aerial dance was clear. Like a bee that has discovered a new supply of nectar, the airplane was pointing the direction the blimp should follow. (It didn’t want to use its radio lest it give away the convoy’s location.)

Twenty minutes later they saw something apparently standing still in the gray water. Closing, they made out the bow of a ship, pointing straight up. The blimp descended 200 feet and circled. There were no signs of life. Yet the plane that had summoned them must have spotted survivors. Perhaps the ship’s lifeboats had moved away. K-3 began to search methodically in ever-widening circles.

Then they saw a tiny raft rise to the crest of a swell. The four men in it waved frantically. K-3 headed into the wind, cut its speed to 15 knots to equal the wind’s velocity, and hovered 50 feet above the raft, struggling to maintain position. The skipper opened a side window and leaned out, holding a megaphone.

“Are there other lifeboats?” he shouted. “Point direction.”

From the blimp they could see the men on the raft cupping their hands and shouting back. But even at low speed the engines were too loud, and no one on the blimp could hear a word. K-3 lowered a wire basket containing sandwiches, hot coffee, water bottles, a small medical kit—and a note with the skipper’s questions, along with a paper and pencil for a reply.

The word was bad: “These all survivors from Norwegian freighter Norness . Other lifeboat overturned. All hands lost.” Still, the crew of K-3 made sure those four lives were saved, standing guard over the raft until a surface vessel answered its radio message and raced to the scene. That made it a good day for the blimp’s crew.

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“The rattlesnakes of the Atlantic,” President Franklin D. Roosevelt called the German U-boats. They were one of Hitler’s most potent weapons. Immediately after Germany declared war on the United States, on December 11, 1941, a flotilla of submarines set out beneath the Atlantic from bases in occupied France to spread death and destruction along the Eastern seaboard of the United States. They struck with stealth and near impunity, taking a grim toll on Allied ships, sometimes within sight of seaside resorts in the Carolinas, Georgia, and Florida.

The German offensive had been carefully planned by Adm. Karl Dönitz, commander of the U-boat fleet, to deliver a blow to the Americans that would be as devastating as the one at Pearl Harbor. By sinking ships at the enemy’s doorstep, the Germans expected to make Americans believe the U.S. Navy was unable to protect the nation’s shores. The resulting loss of men, ships, and cargoes would shake America’s resolve to fight the war in Europe.

The U-boats had easy hunting at first. Two months into the war, they were sinking three or four ships a day, a disproportionate number of them oil tankers. Surfacing in daylight could be risky, but the Germans were quite successful in picking off victims at night. In the first six months of 1942 they sent several hundred Allied ships to the bottom of the Atlantic, killing nearly 5,000 seamen.

Poor planning by the Allies helped them. Merchant ships were permitted to sail singly and unescorted and to transmit their positions in uncoded radio messages. The only protective measure the ships took was to stay as close to shore as possible. That tactic had a big drawback, for cities along the Atlantic Coast were not blacked out. At night their glow silhouetted the merchantmen, making them easy prey. The onslaught threatened the flow of petroleum from Texas and Venezuela and aluminum ore and other goods from South America.

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The desperate situation called for desperate action, but the weapons at the Navy’s disposal were severely limited. Except for a few Coast Guard cutters and some converted oceangoing yachts, the Navy had very few warships to protect the merchantmen. Nearly all its destroyers and destroyer escorts were committed to the Pacific or the North Atlantic for convoy duty.

So the Navy revived an idea that had worked in World War I, when the British had countered the U-boat threat by using nonrigid airships to escort convoys. (The nickname blimp is said to have been coined by a British officer after the sound the gasbags made when flicked with a finger.) The results were impressive: No Allied merchant ship protected by the airships had been lost. Blimps kept U-boats submerged during the day, limiting their movements, and they did outstanding work in rescuing survivors of sunken ships.

The value of airships was clear, and between the wars the U.S. Navy experimented with two types. Garnering most of the publicity were the enormous rigid airships, 700 feet long or more, such as the Akron and the Macon . These behemoths, with multiple gas compartments housed in a huge metal framework, generated reams of newspaper copy, and they looked impressive sailing over the district of an undecided congressman. In the end, though, they proved to be too dangerous and not useful enough to justify the amount of money being spent on them.

Less inspiring but more valuable were the smaller nonrigid airships, or blimps. The Navy experimented with them on a modest scale between the wars, and by 1938 it was maintaining a fleet of eight at Lakehurst for research and training purposes. The Army also experimented with blimps during and after World War I, mostly for surveillance, but abandoned the idea in 1937 and gave its remaining blimps to the Navy. By the time World War II began, no other nation had a military blimp program, partly because most of the world’s reliable sources of helium were in the United States. Hydrogen readily bursts into flame, and experience showed that using it in airships was a bad idea under any circumstances and particularly when the airship might be fired on.

In June 1940, as the situation in Europe deteriorated and the possibility of America’s being dragged into the conflict drew closer, President Roosevelt authorized the acquisition of 48 blimps. (The number would be increased to 200 after Pearl Harbor.) Most of them were K-class, manufactured by Goodyear and equipped for submarine surveillance. A typical blimp was 252 feet long and 65 feet wide, took 425,000 cubic feet of helium to inflate, and was powered by a pair of Pratt & Whitney Wasp radial engines. With a cruising speed of 50 miles per hour and a maximum speed of 65 mph, they could travel 1,500 miles and remain in the air for more than 50 hours. Normally they stayed within 250 miles of shore. (The Navy also operated four even bigger M-class blimps, which used more than 600,000 cubic feet of helium, and for training purposes it had 8 smaller units, which used about 190,000 cubic feet.)

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Blimps made ideal surveillance platforms. Large plexiglass windows, affording visibility in every direction, encircled their bus-size aluminum command cars, which were crowded with instrument panels, electronic gear, the navigator’s chart table, the radio shack, storage racks for ammunition and food, rescue gear, a tiny galley with an electric range, chairs, and a cot.

The sausage-shaped envelope of a K-ship was made of rubberized canvas painted silver to reduce solar heating. The ship got most of its buoyancy from the helium gas it contained, with the shape of the bag providing some extra lift. Inside the envelope were two ballonets, fore and aft, filled with air. The blimp crew maintained trim (level flight) by balancing the air in the ballonets. Pumping more air into the forward ballonet or letting it out of the rear one gave the stern greater lift, thus pointing the nose downward and causing the ship to lose altitude. When the process was reversed, the nose rose and the blimp climbed.

Flying a blimp required two pilots in addition to the command pilot. One manned a large wheel connected to the rudder to set the course and heading. The other handled the elevators that, together with the ballonets, trimmed the ship and drove it up or down. The crew also included a navigator, two ordnancemen, two mechanics, two radio operators, and two riggers.

Between 1942 and 1945, 10 squadrons of blimps were deployed in naval air stations stretching from Massachusetts to Florida and along the Gulf and Pacific Coasts, along with 5 overseas squadrons. Their primary mission was to escort convoys. Blimps protected the ships in three ways: by presenting a large, conspicuous deterrent to submarines considering an attack; by forcing pursuing subs to stay underwater, where their speed was much lower than on the surface and maneuvering was difficult; and, when a sub surfaced, by calling in armed planes and ships and occasionally joining in the attack themselves.

Blimps flew on the seaward side of a convoy at an altitude of 500 to 1,000 feet, moving slowly back and forth along a string of ships that might stretch over many miles, keeping stragglers in line by signaling with blinker lights while watching for U-boats. Blimps could also patrol independent of convoys, looking for surfaced U-boats recharging their batteries or for the telltale sand streaks caused by the screws of a submarine moving close to the bottom. When they found a submerged enemy sub, the crew might drop depth bombs and watch for oil slicks, debris such as pieces of wood and uniforms, or air bubbles that would show they had made a kill.

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Standing orders dictated that if a blimp spotted a U-boat on the surface, it had to keep it under surveillance until a hunter-killer group of bombers (sometimes shore-based and sometimes carrier-based) and naval ships acting in concert took up the chase. Blimps were permitted to attack a U-boat only while it was surfacing or submerging or if a merchant ship in the vicinity was in danger. Otherwise they kept their distance, since a blimp’s huge gasbag gave anti-aircraft gunners a wonderful target.

K-ships carried four 325-pound depth bombs that could kill or damage a submarine if detonated within 50 feet of its pressure hull. They also carried a machine gun in a turret above the pilot for use against vessels. Along with visual sightings, the blimps used a MAD (magnetic airborne detector) to sense the presence of a submarine by noting any distortion in the Earth’s magnetic field caused by a metal hull. They also carried smoke bombs to mark a target area. Later K-ships were equipped with radar, which made night missions possible, and “sonobuoys,” buoys equipped with a hydrophone and radio that were dropped in the sea and could transmit sound from underwater. Allied submarines generally operated in different areas from the blimps, but if there was an Allied sub in the vicinity, the blimp crew would be briefed to prevent friendly fire.

In 1942 the United States lost 454 ships to enemy submarines in Atlantic and Gulf waters. The next year, with increasing numbers of blimps in service and other forms of anti-submarine warfare taking hold, the number fell to 65, and in 1944 to 8. The peak month for Navy blimps was March 1944, when 119 were in operation.

Every pilot in the blimp service dreamed of being the victor in a duel between sea and sky. One of the few who actually accomplished this was Lt. Nelson G. Grills, command pilot of airship K-74 , based at Richmond Naval Air Station, near Miami. On the night of July 18, 1943, K-74 was on a routine mission over the Florida Straits when a bright spot appeared on its radar screen. Grills nosed his blimp down and approached the radar target. Helped by a three-quarter moon, he could clearly make out the silhouette of a moving U-boat against the silvery Atlantic waters, and he could follow its wake.

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Grills faced a dilemma. His orders were to stay out of range of any surfaced submarine and call for support. But he knew from the preflight briefing that two Allied ships, a freighter and a tanker, were within a few miles of the U-boat, and the enemy appeared to be heading straight for them. Clearly the U-boat posed an immediate threat.

At 10 minutes before midnight, K-74 started its bombing run at full speed from an altitude of 250 feet. The reaction from the submarine was immediate. The U-boat, later identified as U-134 , turned sharply to port, its stern facing the approaching blimp. This maneuver gave its twin-mounted machine guns behind the conning tower a clear shot at the airship. Tracers stitched the sky, ripping holes in the blimp’s canvas skin and peppering the gondola’s windows. By this time bullets from the blimp’s forward .50-caliber machine gun were ricocheting off the sub’s deck and conning tower. As the blimp came nearer to its target, Grills saw bright flashes and heard the booming sound of the submarine’s 88-mm cannon. Its shells, he knew, would tear huge holes in the gasbag.

The blimp crossed U- 1 34 at a 15-degree angle, a perfect position for the two bombs carried under the car to straddle the U-boat. With bullets ripping the bag and thudding against the car, Grills signaled the bombardier to release his bombs. A moment later crewmen saw a bright flash on the starboard side of the blimp. With one engine in flames and its envelope shredded, K- 74 was deflating fast and flying at a steep nose-up altitude. Grills hoped his bombs had hit, but he wasn’t sure, and he certainly couldn’t go back and see. The radioman had just enough time to send an “Urgent! Fired upon!” message and give the airship’s position before K- 74 hit the water.

At the “abandon ship” order, the crew jumped into the water—except for Grills, who stayed aboard to destroy classified documents and dump secret electronic gear overboard in case the U-boat crew came to search the remains of his blimp. Then he, too, abandoned the sinking gondola. In the darkness he became separated from his crew. Alone in the water, he oriented himself by the stars and started swimming due west toward the Florida Keys, which he knew were some 25 miles away.

Buoyed by their life jackets, the men in the water floated near the blimp, which was now half submerged. They held hands to stay together, formed a circle for protection against sharks, and waited for daylight and rescue. Fortunately, they were in tropical waters in summertime, so there was no immediate danger of hypothermia. Soon after dawn a twin-engine Navy amphibian plane found the group, but the water was too rough for a landing, and the plane turned away. Thinking the pilot had missed seeing them, the men let go of each other’s hands to wave. In these frantic moments the bombardier, Isadore Stessel, who was a poor swimmer, was carried away by a swell. When the others turned to look for him, he had vanished. A moment later they saw a shark’s fin. The bombardier’s bloody head and shoulders bobbed above the water, then vanished. Shortly after that the destroyer Dahlgren picked up the crew, and a PBY flying boat rescued Grills.

At the time the Navy could not determine whether K-74 ’s bombs had hit the U-boat. After the war it was discovered that the blimp’s bombs had fallen near enough to damage the submarine’s quick-dive tanks. Forced to return to its base on the surface, U-134 was spotted by a Royal Air Force plane, bombed, and sent to the bottom along with its entire crew.

Navy blimps played a crucial role in driving enemy submarines away from coastal sea-lanes. They protected the Atlantic, Gulf, and Pacific Coasts, ranging as far south as Rio de Janeiro. After the Allied invasion of Europe, a few of them patrolled the Mediterranean as well. Over the course of the war blimps escorted an estimated 80,000 vessels safely through areas around the world where enemy submarines were present and rescued hundreds of sailors from torpedoed ships, including surviving crews of sunken U-boats. No ship under blimp protection was ever lost. During four years of service 34 K-ships were lost because of errors and faulty equipment design, and 77 officers and men were killed.

After the war the Navy’s lighter-than-air program developed more sophisticated airships to be used against submarines and as an airborne early-warning system. But improved airplanes and helicopters soon could do everything blimps had done, and in 1961 the Navy ended its blimp program, followed a year later by the Marines. Since then the military services have employed blimps in small numbers for surveillance, meteorology, and other uses where their ability to hover is needed. Their heyday was brief, but in World War II, when the nation’s merchant marine was in danger of being crippled, scores of big, slow, powerful blimps performed a crucially important job better than any other type of craft could have done.