Led Zeppelin This Aint'

When most of us think of the first powered flight, the first thing that comes to mind is the Wright Brothers. They claimed to have been the first to fly a powered aircraft on December 17, 1903.

However, there were several pioneers for powered flight, including Alberto Santos-Dumont from Brazil and an emigrant from Germany to the US named Gustav Whitehead, so the arguments continue to this day about who made the first powered aircraft flight.

Many assume that powered aircraft were the first to fly passengers, but they would be mistaken.

In 1852 Henri Giffard constructed a steam-powered engine that produced three horsepower. He then used that engine to power a 144-foot-long bag filled with hydrogen and flew it a distance of 20 miles at a speed of 6 mph.

But there is an even more interesting powered aerial design that many of us don't know much about.

Count Ferdinand von Zeppelin

In 1898 von Zeppelin began construction of his first Zeppelin: the LZ-1. While building the first zeppelin, he also constructed a floating hangar on Lake Constance in Southern Germany near the Swiss border.

The reason for the floating hangar was simple. It was built on the water so that it could face the wind when launching his LZ-1 zeppelin airship!

The LZ-1 zeppelin made its first flight on July 2, 1900.

The first Zeppelin and its floating hangar on Lake Constantine in 1900

Von Zeppelin planned on building 130 of these airships, and 119 were actually built between 1900 and 1937.

Among them was the famous Graf Zeppelin (LZ-127), built in 1928, and the giant Hindenburg (LZ-129), first flown in 1936.

First Non-StopTransatlantic Passenger Service

Most of us probably think about the airplanes that first crossed the Atlantic, but the truth is that starting in 1928, transatlantic flights became common.

On October 11, 1928, the Graf Zeppelin began non-stop transatlantic passenger service.

It departed Friedrichshafen, Germany, at 07:54 on 11 October 1928 and arrived at NAS Lakehurst, New Jersey, on 15 October.

The Graf Zeppelin was 176 feet long and was powered by five Mayback VL II 12-cylinder 550 hp engines, filled with 2,600,000 cubic feet of hydrogen gas in seventeen lifting cells.

During its career, it made 590 flights, including 144 ocean crossings, and flew more than one million miles.

LZ-127, the Graf Zeppelin, in flight over Rio de Janeiro in 1930.

But, perhaps the most famous zeppelin was the Hindenberg (LZ-129). 

Zeppelin Construction

These airships were made with a rigid structure built of triangular section duraluminum girders. Each of them was a specially heat-treated piece of aluminum and copper. Then they were anodized to prevent corrosion.

Each ship consisted of 15 ring frames and 36 longitudinal ribs.

Lift was provided by 16 hydrogen bags made of multiple layers of cotton fabric brushed with latex gelatin. They contained a total of 7,062,000 cubic feet of hydrogen and could lift a total of 511,500 pounds. This was double the zeppelin's weight when fully loaded. 

Then, the entire frame was covered with cotton fabric painted with a special cellulose varnish which was impregnated with aluminum powder.

This gave the Zeppelin its silver color, but more importantly, it acted as a reflector to protect the hydrogen bags inside from heat and ultraviolet light.

Even as early as the 1900s, aviation pioneers were aware of the dangers of ultraviolet light, the very same ultraviolet light that high-quality aviator sunglasses protect today's pilots. 

The Zeppelin Graf Zeppelin while under construction in Germany in 1928.

The green-shaded items are the longitudinal ribs, while the red-shaded items are the rings.

Under the zeppelin, a gondola was attached with two decks. At the front of the gondola was where the flight crew worked on four-hour shifts.

The Gondola under the Graf Zeppelin being held down by onlookers and passengers.

The flight crew numbered 40 pilots and engineers, and each pilot could only work about four hours before being relieved because the temperature could reach 122 degrees Fahrenheit. The task of piloting zeppelins was very taxing, so new pilots were rotated throughout the flight.

The top deck of the gondola contained 50 private cabins for passengers, complete with sleeping berths. 

The large public areas included a galley, public bar, and smoking lounge on the lower "B" deck.

The deckplan of the Graf Zeppelin's gondola.

The huge airship was powered by four liquid-cooled, fuel-injected Daimler-Benz V-16 diesel engines attached to 19-foot four-bladed fixed-pitch wood propellers.

It had a cruising speed of 76 mph and could cross the Atlantic Ocean in only four days. 

During its career, the Graf Zeppelin made 590 flights, including 144 ocean crossings, and had flown more than one million miles.

The Hindenburg

Most of us have heard of the Hindenburg disaster that occurred at Lakehurst, NJ, on May 6, 1937.

The Hindenberg was the largest dirigible ever built and the pride of Nazi Germany. 

At a length of 804 feet, it had a diameter of 135 feet, a gross weight of approximately 215,000 pounds, and was powered by four 1,100-horsepower diesel engines for a maximum speed of 84 miles per hour.

The German Zeppelin Airline Company operated the Hindenburg.

In 1936 it carried a total of 1,002 passengers on ten scheduled round trips between Germany and the United States.

The Hindenburg opened its 1937 season by completing a single round-trip passage to Rio de Janeiro, Brazil. On the evening of May 3, on the first of 10 scheduled round trips between Europe and the United States, it departed Frankfurt, Germany. 

The Hindenburg encountered strong headwinds on its Westward journey, arriving a few hours late for an early-evening landing at Lakehurst three days later on May 6.

The Hindenberg was carrying only half its full capacity of passengers (36 of 70) and crewmen (61, including 21 crewman trainees) during the flight but was fully booked for its return flight.

Many of the passengers with tickets to Germany were planning to attend the coronation of King George VI and Queen Elizabeth in London the following week.

The Hindenburg over New York City on the afternoon of May 6, 1937.

 The Hindenburg was hours behind schedule when it passed over Boston on the morning of May 6. It's landing at Lakehurst was expected to be further delayed because of afternoon thunderstorms.  

Advised of the poor weather conditions at Lakehurst, Captain Max Pruss charted a course over Manhattan Island, causing a public spectacle as people rushed out into the street to catch sight of the airship.

While waiting for the weather to improve, Captain Pruss took passengers on tour over the seashore of New Jersey.

After finally being notified at 6:22 p.m. that the storms had passed, Pruss directed the airship back to Lakehurst to make its landing almost half a day late.

This would leave much less time than anticipated to service and prepare the airship for its scheduled departure back to Europe. Therefore, the public was informed that they would not be permitted at the mooring location or be able to visit aboard the Hindenburg during its stay in port.

Landing Timeline

Around 7:00 p.m. local time, at an altitude of 650 feet (200 m), the Hindenburg made its final approach to the Lakehurst Naval Air Station. This was to be a high landing, known as a flying moor, because the airship would drop its landing ropes and mooring cable at a high altitude and then be winched down to the mooring mast.

This type of landing maneuver would reduce the number of ground crewmen but would require more time. Although the high landing was a standard procedure for American airships, the Hindenburg had performed this maneuver only a few times in 1936 while landing in Lakehurst.

At 7:09 p.m., the airship made a sharp full-speed left turn around the landing field to the west because the ground crew was not ready.

At 7:11 p.m., it turned back toward the landing field and valved gas. All engines idled ahead, and the airship began to slow. Captain Pruss ordered aft engines full astern at 7:14 p.m. while at an altitude of 394 ft (120 m) to try to brake the airship.

At 7:17 p.m., the wind shifted direction from east to southwest, and Captain Pruss ordered a second sharp turn starboard, making an s-shaped flightpath towards the mooring mast.

At 7:18 p.m., as the final turn progressed, Pruss ordered 300, 300, and 500  kg (660, 660, and 1100 lb) of water ballast in successive drops because the airship was stern-heavy.

Hindenburg’s gas cells had 14 manually-controlled maneuvering valves located just above the axial walkway, which could be operated from the main gas board in the control car; electric meters measured the fullness of each cell and could be monitored in the control car.

The forward gas cells were also adjusted. As these measures failed to bring the ship in trim, six men (three of whom were killed in the accident) were then sent to the bow to trim the airship.

At 7:21 p.m., while the Hindenburg was at an altitude of 295 ft (90 m), the mooring lines were dropped from the bow. The starboard line was dropped first, followed by the port line.

The port line was overtightened as it was connected to the post of the ground winch. The starboard line had still not been connected. A light rain began to fall as the ground crew grabbed the mooring lines.

At 7:25 p.m., a few witnesses saw the fabric ahead of the upper fin flutter as if gas was leaking. Others reported seeing a dim blue flame – possibly static electricity or St. Elmo's Fire – moments before the fire appeared.

On board, people heard a muffled detonation, and those in the front of the ship felt a shock as the port trail rope overtightened; the officers in the control car initially thought a broken rope caused the shock.

The Hindenburg was quickly engulfed in flame and begin to fall moments after the start of the fire.

The Hindenburg burning next to the mooring tower at Lakehurst, NJ pn May 6, 1937.

There were a total of 35 deaths out of 97 people on the airship, including 13 of the 36 passengers and 22 of the 61 crew. Most of the survivors were seriously burned.

Thus the career of passenger airships came to an end.

I hope you enjoyed this trip through some of the history of aviation. If you enjoyed this trip, and are new to this newsletter, sign up to receive your own weekly newsletter here:: Subscribe here.

Until next time, keep your eyes safe and focused on what's ahead of you, Hersch!