Hybrid Airship Inspirations: Santos-Dumont

As written previously, this novel combination aircraft was not without a real-life precedent. Most of the inventions in the Tom Swift series are enhancements of real inventions. Although the design was not ultimately successful, the combined aeroplane-dirigibile balloon was an area of interest for several inventors.

It is difficult to know precisely which publications were most influential to Edward Stratemeyer and Howard R. Garis to inspire these books. However, several examples may be found with some elements in common with the story descriptions. For example, another Syndicate series ghostwritten by Garis is the Motor Boys (1906-24). The early volumes included stories with automobiles and motor boats. The 1910 volume, The Motor Boys in the Clouds, is the first of several stories with a hybrid aircraft, the Comet.

The motor ship was to consist of a big cigar-shaped bag of very strong material to hold the gas. It was divided into several compartments, so that in case one or even three or four were punctured there would be enough sustaining power to keep the ship and its crew afloat. The gas used was a combination of hydrogen and another vapor, the secret of which Mr. Glassford would not disclose. Sufficient to say that it was a very powerful combination.

The gas bag fitted inside with a light but very strong framework, braced with piano wire, and on either side of this frame, standing at right angles to the long bag, were several panes, made of light canvas, stretched over poles of bamboo. These, in effect, made a combination balloon and aeroplane, giving the advantages of both, and somewhat neutralizing the defects of each one.

Below the bag, with the framework supporting the planes, was the body of the ship--the car--containing the motor and the devices for operating it, as well as the rudders, propellers and planes which could be shifted.

The car was large, or, rather, the plans called for a good-sized one. There would be a comfortable cabin, in which the travelers would live during the day, doing their cooking on a stove which utilized the exhaust gas from the motor. There was also another room, where five small berths provided sleeping accommodations. These berths could be folded up during the day, and as the room containing them was well forward, it made a good place to sit when the ship was in motion, for an excellent view could be had from the big windows.

The entire car was enclosed, so that storms would not affect the travelers. The motor was in a small room by itself, and there was a little pilot house, on top of the bunk room, in which the operator stood, being able to control, stop or start the motor from there, as well as adjust the two rudders or shift the planes.

There were two sets of rudders, though one, as has been explained, was more like a big box-kite than a rudder. This controlled the depression or elevation of the ship. The other, shaped like a fish-tail, sent it to the right or left.

The planes on either side of the gas bag were intended to better balance the motor ship, to render it less liable to be sent out of its course by contrary winds, and to support it in case of accidents. The planes were on the same principle as a bird's wings when it is gliding or swooping down from a great height.

There was ample store room for supplies, provisions, some ballast and a few duplicate parts of the motor. Water was carried in a large tank, and there was another for a plentiful supply of gasolene. The motor ship had many novel features, and there were so many points of interest about is, as Mr. Glassford explained to them, that the boys hardly noted them all at the time of going over the plans.

The distinctive box-kite wings may have been inspired by this photo of Alberto Santos-Dumont's airship from 1906.

Although this appears to be a combination aeroplane and dirigible, it was the reuse of one of his gasbags (No. 14) to lift his heavier-than-air biplane (No. 14bis) for testing. This gasbag was 41 m (134.5 ft) long, 3.4 m (11 ft) in diameter, and had a volume of 186 cubic meters (6,569 cu ft).

Santos-Dumont's No. 16 was an actual hybrid design with both lighter-than-air (LTA) and heavier-than-air (HTA) qualities. This 99 cubic meter (3,496 cu ft) gasbag was 21 m (69 ft) long and 3 m (10 ft) in diameter. As noted in Scientific American (6 Jul 1907) the gross weight of the aircraft exceeded the gasbag's lifting capability by about 120 kg (264.5 lbs) so the wings were expected to carry the rest of the weight. It crashed on its first flight attempt on June 7, 1907.

In this experiment the propeller was started up and the flier ran along the ground on its wheels at a moderate rate. The rear end was held by a mechanic, who let go after about a hundred feet. But owing to an accident, the flier did not rise as expected, but ran head down upon the ground. The propeller struck the balloon and tore it, letting out the gas. It also struck the ground and was consequently somewhat injured. The upper bamboo pole broke, and the frame in general was damaged. Santos-Dumont did not suffer from the fall. He explained the probable reason of the mishap, stating that he was not aware that the flier had been held in the rear, and in consequence thought it was free at the start. Thus he did not handle it properly, and it was owing to improper management of the planes that the machine acted as it did. On the other hand, it is thought that the accident was due to the fact that the column of air driven by the propeller was directed against the rear plane frame and also against the under side of the balloon in the rear, and this caused the back end of the balloon to rise, tilting the front end downward.

There were other hybrid airship designs which could have influenced the descriptions in the Tom Swift and Motor Boys series and a few of those will be described in a future installment.

• The image of the Santos-Dumont airships are used with permission from the Rosebud pages at http://www.earlyaviator.com