The place our story starts is with the man Zeppelins were named after: Ferdinand Adolf Heinrich August Graf von Zeppelin, or Count Zeppelin to his friends. He was a German aristocrat who was born rich and married richer, and had until 1890 been a General in the Kaiser's army. Count Zeppelin was a patriot and decorated war hero, with a reputation for bluntness. This bluntness one day managed to annoy the Kaiser himself, and Count Zeppelin found himself prematurely retired. Denied his passion for the Army, Zeppelin turned to his other great passion: airships. Count Zeppelin and his astonishing moustache.
Count Zeppelin and his astonishing moustache.
Count Zeppelin was convinced Germany would need 'sky-crusiers' (as he called them) if she was to continue to rise in greatness. During the American Civil War, Lt. Zeppelin had served in the Union army as a Military Observer, and had been greatly impressed in a balloon ride he took in St. Paul, Minnesota. His first proposal in 1895 to the military was a balloon-train type thing, propelled by ludicrously heavy gas engine making about as much power as a VW Beetle. This was rightfully rejected by the military, but sympathetic men on the review board connected Zeppelin with engineers who could help him refine his idea. The first craft made by Zeppelin and his engineers was rather impressive. Launched from a specially constructed floating hanger, LZ 1 (Luftschiff Zeppelin 1, Airship Zeppelin 1 in English) took flight in July 1901.
The design Count Zeppelin had refined partially through experience and partially by his engineers was fairly simple. The cigar-shaped hull was made from thin aluminum struts. Inside were the hydrogen lifting cells, which were made of something called gold-beater's skin, a very fine leather usually used for making gloves. Two central gasoline engines drove four propellers. There was a central cabin near the engine room, and fore and aft gondolas. Initially, these gondolas were open to the wind, kind of like twin aluminum boats under-slung the fuselage. Control surfaces were fairly primitive, having rudders and elevators, but not in the cross shape you may be familiar with.
The German military, especially the Navy, was interested in Zeppelin's skyships for several reasons. The rigid airship as it was forming could climb faster, and fly higher then aircraft of the day, a fact that remained mostly consistent throughout WW1. They had already shown a capacity for enormous range, and could carry radios, which is something airplanes at the time couldn't do. In addition to that (and this is possibly the most important detail) airships were considerably more forgiving of mechanical breakdowns. Engines, for example, could be fixed “on the fly.” This forgiving nature had considerable appeal at a time when flight itself was still a new endeavor.
The single exception to this forgiving nature was of course, the hydrogen lifting gas. Hydrogen, despite what you may think, is actually very difficult to ignite in it's pure state. As we will see, airships were frequently riddled with bullets to little ill effect. It's when hydrogen mixes with oxygen that you get, well, the Hindenberg disaster. In Zeppelin's experimental days - despite all the accidents - nobody was injured, let alone killed. This is somewhat remarkable as Zeppelin used his leftover experimental airships to form the world's first airline. Both a practical use of resources and a calculated ploy to cultivate the airship as a national symbol, DELAG was entirely successful. Germany was a power on the rise, thanks to education and technology, and the airship had become a potent patriotic symbol of this.
The first military airship was made for the Navy was creatively named L 1. She was 518 ft long, displaced nearly 800,000 cubic feet and had a crew of 14. She also had 20 tons of useful lift, and featured 3 centrally mounted engines of 180 hp driving the four propellers. Made with everything the Zeppelin company had learned about airships, she was state of the art. The Navy wanted L 1 and her sister ships for a number of reasons, mostly for (if you will pardon the pun) a pilot project regarding big rigid airships. Aside from actual Naval reconnaissance abilities, this commissioned series of airships would hopefully give engineers and planners a good idea about what capabilities the next class would require. This was especially important as if the new, hypothetical ships were substantially bigger, it would require new, larger hangers, and larger sheds at the factory. Launched in late 1912, L 1 was a success, showing every intention of being all everyone hoped. She made shakedown and training flights almost every day into 1913. The Imperial forces made plans for 2 squadrons of 5 ships each. L 2, an improved, L 1 was taking shape at the Zeppelin company.
 |
| L 1. |
 |
| L 1's Control Car. Note the integrated handles for the ground crew. The big box at right is a radiator. |
Heavy weather was reported incoming to the area. The Captain of L 1 abandoned his more ambitious flight plans for the day, and stayed close to the squadron of destroyers he was escorting. Just before L 1 returned to base, the storm hit. A torrent of rain was followed by a violent updraft, throwing L 1 to 6000 feet, considerably above her 'pressure height' of 2000 feet. This caused L 1's fail-safe valves to vent gas. Suddenly much heavier, She was then was hit with a violent downdraft, and as the crew frantically dropped ballast and reversed engines for more lift, L 1 plopped into the sea. The crash killed or knocked out the men in the gondolas; they were never seen again. The only survivors were from the mid compartment. Even though a passing tramp steamer was close at hand to the crash site, only 6 out of the crew of twenty survived.
The crash created a bit a of a shock throughout Germany. As said, these were the first deaths involving airships. The Zeppelin company blamed the military for 'overloading' L 1, and predictably, the military blamed the company. What had really wrecked the L 1 was simple ignorance: meteorology was in it's infancy, and the updraft/downdraft action of a storm front was unknown. While the early Hydrogen-based aviators knew “lightning = bad” more complex phenomena would remain beyond them, sometimes with disastrous results.
L 2 launched on the 6th of September 1913, just two days before L 1 met her demise. The same basic design as L 1, L 2 was about 200,000 cubic feet bigger, and had several aerodynamic tweaks. The gondolas were now enclosed (over the objections of Count Zeppelin, who insisted that open gondolas allowed the crew to 'sense the air') and the support struts to the propellers were enclosed in triangles of canvas. She made ten shakedown flights without incident, and then on October 17th , a simple altitude test was scheduled. It was, however, to be a red-letter day. On this flight, L 2 would have a number of top brass along for the ride: several engineers, including her designer from the Zeppelin company, and the head of the new Naval Aviation department.
 |
| The L 2. |
The morning of the 17th was a sunny and warm, a perfect fall day...and then, embarrassingly, a delay. One of the engines would not start after L 2 was brought out of her shed, and some two hours were spent rebuilding the engine, presumably as officers scowled at the mechanics. At 10 am, all was put right, and L 2 took off, circled the field, and then began to climb. It's around this time observers noticed large jets of flame shooting out of L 2's exhaust ports. This was shortly followed by an explosion that blasted flame through the airship's length. Set ablaze, L 2 fell, her frame buckling with an explosion that broke windows a mile distant. The glowing skeleton of the L 2 fell to earth near some laboring Army engineers. The engineers rushed to help, but the wreck was so hot that they were repulsed. When the fires were out, they cut into the wreck to search for survivors. Three men were found alive, horribly burned. Two of these men died at the site, and a third lingered till nightfall in a Berlin hospital.
The L 2's final flight was the result of two factors, the first being the delay on the ground. While the mechanics tinkered, the sun warmed the lifting cells, causing them to expand to full “pressure height.” (In WW1-era German airships, lifting cells were trimmed before flight to a certain altitude. As a ship rose, the cells would inflate as air pressure became less. When they reached 100% inflation, they have reached the pre-set pressure height. From this altitude and below, an airship can fly without risking venting the hydrogen gas. Above pressure height - in an extremely dubious safety feature - valves would vent gas, both to prevent cell explosions, and to slow the ascent on an out of control airship.) So, when L 2 took off at 100% pressure, her increasing altitude caused hydrogen venting. In what I think I'll characterize as a design flaw, the second factor was that the valves were on the bottom of the pressure cells, and flooded the gangway with hydrogen. Some of this volatile mix of hydrogen and oxygen got sucked into the rear engine, which ignited, which in turn ignited the entire gangway, and, well, downhill from there.
These two accidents were a sore blow to the German airship program. In some ways it mirrored the Soviet 'Nedelin catastrophe', the accident killed several key technical personnel as well as killing (after the L 1 disaster) the only trained airship crew. This also saw the end of Count Zeppelin having anything to do with the actual design of airships. Not that he had made any design changes that caused the L 2 disaster; but as mentioned before, the Count was blunt. So it's no surprise the Count started a public argument with Adm. Tirpitz about who was to blame for the L 2 disaster. During the state funeral of the men who died in the L 2 disaster. From this point on Zeppelin was in charge of his company, but as a figurehead, and a increasingly distant and bitter one at that.
Despite all this, the military, especially the Navy, were still interested in rigid airships. With greater control over production, the Navy could now commission the much larger airships that it felt would be capable of long range scouting. (Count Zeppelin had the capitalist’s preference of using existing capital instead of building newer, larger factories. This limited the size, and thus the capability, of the airships produced.) And the U.K. was definitely scared of airships; when the L 1 first took flight, it resulted in a rash of UFO-esque 'sightings' of airships gloaming over the British landscape.
And a rival firm had emerged for the Zeppelin company. In 1909, an engineering professor named Dr. Schutte set up the Schutte-Lanz airship works. As Dr. Schutte was an actual engineer, he had no problem with applying science to some of the, ah, idiosyncrasies of the Count's designs. He was the first one to test out airship designs in a wind tunnel, for example, a suggestion that would have caused Count Zeppelin to bristle his moustache. (As it turns out, symmetrical front and rear airships have drag issues that a tapered rear end does not have.) All these good ideas would create the old-timey airship as you know it, as when WW1 broke out, the German Government became the sole possessor of all Schutte-Lanz's patents, allowing Zeppelin company to borrow whatever good ideas they wanted. One idea that went distinctly un-borrowed was the trademark of Schutte-Lanz airships, a rigid frame constructed out of plywood. This plywood had a tendency to soak up humidity in certain environments, (IE the North Sea) and weigh the airship down. At any rate, the SL airships, as they were designated, never performed as well as the Zeppelin designs. Usually SL type airships were shuttled off to less demanding work, usually in the army. At any rate, the government, pleased to foster competition, immediately placed lots of orders with Schutte-Lanz.
The Imperial Army took advantage of this new source of hydrogen floaty-things. Now that the concept of airships had been shown to have military uses, the Army (the eternal dickish big brother to the imperial navy) bought most of SL's output. Thus, at the start of the great war, the service with most of the airships was the Army, not the Navy, despite the Navy having much greater need for them, as we will see.
It's here we must end, with the introduction of a new character. The new commander of the Naval airship division was a man named Peter Strasser. In the source I'm getting most of my info from, he is described as 'one of the outstanding naval officers on either side of the first World War.' In addition to being a leader of men, he also had a keen technical mind that grasped the new technical challenges that operating airships brought. Well loved by his men, he also became an advocate for the use of airships, especially for bombing Britain. When the war actually dawned, this activism and energy set him and the naval airship division apart from the rest of the German Navy. While surface fleet was doomed to passivity, the Zeppelin crews were determined to attack as much as possible.
No comments:
Post a Comment