Dark Autumn

DARK AUTUMN
THE 1916 GERMAN ZEPPELIN OFFENSIVE

On the night of October 1, 1916, the German Navy Zeppelin L-21 was pushing her way through the high, thin air over Central England near Norfolk. As the airship cleared a bank of clouds, her commander, Captain Kurt Frankenberg, saw 70 miles to the south, another zeppelin held in the bright glare of the London searchlights. Strands of clouds drifted by, obscuring his view, and then with wondrous clarity he again saw the other airship. She was in flames, glowing in the evening sky, falling quickly to the earth. L-21's captain and the few other crew members who saw this dreadful sign hanging in the sky were sure what they had witnessed. Another German airship was out there this night, and it had just plummeted to the ground in fiery ruin. They did not know it at the time, but the blazing ship they had seen was the German Navy Zeppelin L-31, commanded by airship ace Heinrich Mathy. His death and the loss of his crew had far-reaching repercussions for the German airship service.

"...you know that I'm no coward. Out in eastern Asia we made many hair-raising voyages through typhoons. But I dream constantly of falling zeppelins. There is something in me that I can't describe. It's as if I saw a strange darkness before me, into which I must go."
Chief Machinist Mate, German Navy Airship L-31

Introduction

At the start of World War One, lighter-than-air technology was older than other aviation technologies and showed much promise. The airships being built by the Zeppelin Company in Germany were gigantic machines by the standards of the day, and they were seen as tangible fruits of the inevitable march of progress. An airship had graceful lines, enormous size, and a characteristic sound, the drone of their great multiple propellers beating the air. People seeing them were caught in a spell, so impressive was the very sight of a zeppelin. The heavier-than-air aircraft of the day were still very flimsy affairs, barely strong enough to carry one or two people. It is no surprise then, that these lighter-than-air vessels capable of lifting several tons were seen as the wave of the future for aviation.

As the war progressed, the German Navy and Army each built their own mutually exclusive airship fleets. The Navy zeppelins however, were usually of aluminum Zeppelin Company manufacture, whereas the Army often used the wooden Shutte-Lanz or "SL" ships rejected by the Navy due to their excessive weight. Both forces began conducting bombing missions over England, believing that aerial bombing would ultimately destroy that country's industrial base. This overconfidence in the effectiveness of turn-of-the-century high explosives paralleled similar beliefs in most military circles at the time. It all combined into a powerful sensation that the awe inspiring airships could never fail in whatever task they chose. For the first year, it seemed they might be right. German airships ranged over England impeded only by the weather. Flying heavier-than-air biplanes at night was a still a very dangerous pastime, and the few planes able to find the airships could do little more than put a few small holes in them.

By 1916, there were two generations of German airships employed in combat. The L-13 through L-24 were older ships, which made up the majority of any attack force. The newest ships were the L-30's, of which five had been built; the L-30, L-31, L-32, L-33 and L-34. High hopes were pinned to these latest vessels. They were far larger than the previous generation of zeppelin, with a hydrogen capacity of 1,589,000 cubic feet, which gave them a much greater bomb payload. They were however, only marginally faster and could climb no higher than their predecessors, something not considered necessary at the time. No attempt was made to anticipate the British reaction to being bombed with impunity. Since all past methods of destroying zeppelins involved shooting them full of holes, increased lifting capacity was considered to be an adequate solution. It would soon be discovered however, that Great Britain had found a way to ignite the flammable hydrogen gas which gave all zeppelins their lifting power.

Airshipmen dwelt heavily upon the subject of being in a burning zeppelin. To stay on board meant possible survival, but an overwhelming probability of burning alive. The alternative was to jump, a leap to certain, but quick, death! One of Peterson's men commented brusquely that there would be no time for deliberation, that it would all happen much too quickly. Either way, it was a personal decision which every man dwelt upon to the point of obsession. When L-31 went down in flames at Potter's Bar, her Captain, Heinrich Mathy, chose to jump. He was the only zeppelin Captain known to have done so, and also the only person to have momentarily survived the landing. When local farmers found Mathy still wrapped in his leather flight jacket, he was face up in the field near the burning wreckage of L-31. He still lived, but only for a few minutes, and one wonders whether he had decided on jumping long before, or whether he leapt to his death in a last moment of fear and decision.

"Our nerves are ruined by mistreatment. If anyone should say that he was not haunted by visions of burning airships, when he would be a braggart. But nobody makes this assertion; everyone has the courage to confess his dreams and thoughts."
Pitt Klein, German Navy Airship L-31

In the summer of 1916, three new types of British machine gun ammunition which had been under development for years became available for general use. Two types, named "Pomeroy" and "Brock," after their inventors, were explosive bullets. The third, called "Buckingham", was a phosphorus incendiary bullet. Any one of these bullets was only marginally effective when fired at a zeppelin, but when mixed, they formed a lethal combination. The explosive rounds blew holes in the zeppelin's gas cells, allowing the hydrogen to escape and mix with the oxygen outside, forming an explosive mixture. The incendiary bullets then ignited the mixed gases! This new "mixed ammo" sequence was to become Britain's wonder weapon against airships

The Autumn Offensive
In the summer of 1916, the new L-30 class ships were delivered to the German Navy, and Peter Strasser, the Leader of Airships, planned an all out offensive against England. He was determined to show once and for all that the zeppelin fleet could pour enough explosives onto targets in England to make a material difference in the war. There was no doubt as to their morale benefits, the German people loved the zeppelin fleet, and each raid was greeted with the greatest fanfare throughout Germany. England however, was seething with anger, so much so that when one airship crashed at sea, a British trawler nearby violated the "code of the ocean" by not rescuing the airship's crew, standing by to watch them drown instead!

Three raids were carried out during the first "Raiding Period" of Autumn. On July 31, August 2 and August 8, Navy airships arrived over Britain during late evening and returned to German airspace by morning. These raids were uneventful, both in the amount of damage caused to ground targets or airships. As in many previous missions, the airships continued to overestimate the damage they inflicted, often not realizing that their bombs were dropping into the sea! However, they also suffered little or no damage from the still ineffective British air defenses.

The second raiding period began with another marginally effective raid on August 24, followed on September 2 by the largest zeppelin raid of the war. Late on the afternoon of that day, 12 Navy airships; L-11, L-13, L-14, L-16, L-17, L-21, L-22, L-23, L-24, L-30, L-32 and SL-8 were all sent into the air. For once, army ships were also to attack the same night. Four Army airships: LZ-90, LZ-97, LZ-98 and the SL-11 took off from their bases and headed for England. The sixteen ships carried a total of 32 tons of bombs.

LZ-98, commanded by Ernest Lehmann, future commander of the airship Hindenburg, approached from the southeast, arriving over the Thames River at Gravesend. Believing that he was over the London dockyards, he dropped his bombs and made off to the northeast, briefly encountering a British aircraft piloted by Second Lieutenant William Robinson before escaping into the clouds.

British examine wreckage of SL11

The LZ-90 crossed the coastline at Frinton and bombed Haverhill after accidentally losing her sub-cloud car over Manningtree. The SL-11, commanded by Wilhelm Schramm, arrived over northern London at St. Albans. As she bombed the northern suburbs, the airship was picked up by searchlights at Finsbury and Victoria Parks. Turning back to the north, the SL-11 was spotted by Second Lieutenant Robinson, the same pilot who had seen the LZ-98. Robinson approached and fired two full drums of the new Brock-Pomeroy ammunition to no effect. As the zeppelin cleared the searchlight defenses, the British plane made one more pass, firing another full drum into the airship's side. This time, a bright glow showed inside the ship, and within seconds, the fabric burned away as the airship turned into a blazing torch. Her slow descent to earth at Cuffley was not only seen by all of London, but also by the Navy zeppelins then making their approach. The L-16, commanded by Erich Sommerfeld was less than a mile away from SL-11 when she burst into flames, and she attracted the attention of one of the British pilots chasing SL-11. Sommerfeld however, sped off to the north, escaping the glare before the British planes could arrive at his position. Of all the airships, Frankenberg in the L-21 correctly deduced to cause of SL-11's loss. He and his crew 30 miles to the north could plainly see two aircraft around the Army airship, and after she caught fire, one was seen to drop red and green flares (which Robinson did do). The rest of the airships completed their bombing runs all across eastern England and safely returned to their bases, having dropped a total of 17 tons of explosives on English soil. The bombing caused £21,000 worth of damaged, at the cost of 16 airshipmen dead, and one £93,000 airship lost.

Secret funeral for crew of SL11. Public outcry required military honors to remain discrete.

The third raiding period began when 12 navy airships headed for England late in the afternoon of September 23. The navy crews had been dismayed by the destruction of SL-11 three weeks previously, but that had been a wooden army ship. Certainly such a thing could not happen to the veteran navy captains in their true Zeppelins. The new L-30 class ships, led by Heinrich Mathy in the L-31, worked their way southward and crossed the southern English coast. This route assured a strong tail-wind and speedy flight past the most dangerous anti-aircraft areas over London. The other smaller Navy ships; L-13, L-14, L-16, L-17, L-21, L-22 and L-23 took the direct route into the Midlands, with only the L-17 causing any casualties at Nottingham. Captain Alois Böcker in the L-33 was the first to arrive over the capital. He dropped most of his bomb-load on the East End, around Bow and Stratford, with the airship crew reporting visible fires and explosions with each bomb burst . However, a shell from the defenses over Bromley exploded inside the ship, causing tremendous physical damage but no fires. She dropped much of her water ballast, reported by the ground spotters as a smoke screen, and made her way eastward, losing 800 feet of altitude each minute. After a dangerous encounter with a British airplane which pumped several drums of Brock-Pomeroy ammunition into L-33 to no effect, the airship came to earth at Essex, where Böcker and his men jumped to the ground and fired several flares into her. They were promptly captured as L-33 burned to the ground, mostly intact.

The bare girders of L-33 after her burning.

Mathy, in L-31, arrived an hour after Böcker. At 12:15 A.M. he reported seeing an airship (it was indeed Böcker in L-33) to the east, with large fires burning on the ground in her wake. He followed a course over Streatham, Brixton and Kennington, dropping most of his bomb-load on the highway running through there. He then made his escape over Northern London at maximum speed. At 1:15 a.m., Mathy saw another airship over what he thought was Woolwich. It was Captain Werner Peterson in the L-32, which burst into flames and crashed to earth as Mathy and his crew looked on. Mathy's report on the event was terse, but there was no doubting its traumatic effect on the crew.

L-32 had come onshore after circling for about an hour. Peterson's last radio message received was garbled, but it is possible that L-32 had engine trouble and circled until repairs were made. Up to that point, he and Mathy's ship had been cruising together. When L-32 broke out of the cloud cover over the Thames River, she was spotted almost immediately and pinned in the searchlight beams of the city's eastern defenses. Peterson may have realized his danger, because L-32 dropped her bombs in rapid succession and turned toward the sea while attempting to gain altitude. First Lieutenant Frederick Sowery was in the air that night and nosed his British built BE2c 4112 biplane toward the zeppelin which was so dazzlingly illuminated by the searchlights. After firing two drums of Brock-Pomeroy ammunition at the airship, he made a third pass, firing into the side of the zeppelin until he saw flames on its outer fabric. L-32 quickly caught fire and with her hydrogen burning off like a blowtorch, she dropped slowly to the ground near Snail's Hall farm, Billericay, killing all on board. After "firing" the zeppelin, Sowery dropped a red Verys Light (flare) and then landed at Sutton's farm. Officers of the Naval Intelligence Division were first on the scene and despite the heat, they raced through as much of the wreckage as possible (Seen at left). They were rewarded with a copy of the German Navy Cipher Book, which Peterson had allowed on board the L-32 against regulations. It will never be known why he allowed it, if he even knew that it was on board. Its capture was a boon to the Royal Navy code breakers.

The loss of both L-32 and L-33 had a serious effect on morale. The crash of an army airship was one thing, but the loss of two veteran navy captains, their crews and their new ships was too much. The next raid, just two nights later was far more cautious. Captain Ganzel of the L-23 was dismissed after the raid due to his erratic behavior. His nerves were wrecked and he was transferred to surface fleet duty. Horst von Buttlar in the L-30 made a cautious approach near the English coast at Cromer, dropped his bombs in the sea and turned back. Mathy in L-31 made an audacious attack on Portsmouth, a previously untouched target. Unfortunately for him, the searchlight defenses were very strong, and he mistakenly dropped his bombs into the harbor instead of on the Navy yard. The British, who knew from intercepts that it was Mathy, were so astonished at not being bombed that they thought it must have been a reconnaissance flight. A tribute to their personal opinion of Mathy.

The wreckage of L-31 as it came to rest at Potter's bar.

October 1, 1916 was the last night of this bombing period. Eleven airships headed for England, with only the two L-30's permitted to attack London. L-30 again reported having bombed targets when, in reality, she was not spotted at all over England. Mathy's L-31 approached London from the Northeast, finally

Above: The only known photograph taken of the L-31 as she fell to the ground at Potter's Bar

throttling his engines down in an attempt to float silently over the listening searchlight operators on the ground. By 12:30, at least four defense planes were in the air when Mathy fired up his engines and attracted the searchlight beams. As the guns on the ground opened fire, Mathy dropped his entire bomb-load and turned west. L-31, now several tons lighter, rocketed skyward and almost escaped. She had cleared the A.A. defenses when Second Lieutenant W.J. Tempest dove his plane under the airship, firing a drum of Brock-Pomeroy ammunition into the ship's keel. Suddenly, the zeppelin turned a bright red inside, and a burst of red flames shot out of her nose. L-31 plummeted straight to the ground like a freight train, nearly taking Tempest and his plane with her. As Tempest corkscrewed his plane out of the way, the burning airship passed him and landed at Potters Bar. Local villagers running into the field found a man lying on his back, half-imbedded in the ground. He was alive and unburned, but died soon after. His identity disc was marked: "Kaptlt. Mathy. L31"

After the morning of October 1, 1916, German naval airships never again approached Great Britain with their former sense of impunity. In 1917 and 1918, new airships were built which easily exceeded the ceilings of British aircraft, but sacrifices in payload and durability were so great, and high altitude bombing accuracy was so poor, that the original goal of bombing England into submission was quickly lost. The naval airship division was slowly relegated to the status of reconnaissance arm for the fleet, and as propaganda weapon for the government. The leader of airships, Peter Strasser, continued to push for his view of a "war ending" zeppelin offensive. He died on August 5, 1918 while leading the last Zeppelin raid of the war.

recommended reading
Castle, H.G. Fire Over England. Secker & Warburg, 1982
Manchester Guardian History of the War. John Heywood LTD. 1916
Robinson, Douglas. The Zeppelin in Combat. Schiffer Military History, 1994
Scheer, Reinhard. Germany's High Sea Fleet in the World War. Cassel & Co. LTD. 1920