My Airships/Chapter 10

by Alberto Santos-Dumont

I GO IN FOR AIRSHIP BUILDING

IN the early spring of 1899 I built another air-ship, which the Paris public at once called "The Santos-Dumont No. 2." It had the same length and, at first sight, the same form as the "No. 1"; but its greater diameter brought its volume up to 200 cubic metres—over 7000 cubic feet—and gave me 20 kilogrammes (44 lbs.) more ascensional force. I had taken account of the insufficiency of the air pump that had all but killed me, and had added a little aluminium ventilator to make sure of permanency in the form of the balloon.

This ventilator was a rotary fan, worked by the motor, to send air into the little interior air balloon, which was sewed inside to the bottom of the great balloon like a kind of closed pocket. In Fig. 5 G is the great balloon filled with hydrogen gas, A the interior air balloon, VV the automatic gas valves, AV the latter's air valve, and TV the

ACCIDENT TO "No. 2," MAY 11, 1899

(FIRST PHASE)

tube by which the rotary ventilator fed the interior air balloon.

The air valve AV was an exhaust valve similar to the two gas valves VV in the great balloon,

with the one exception that it was weaker. In this way, when there happened to be too much fluid (i.e. gas or air, or both) distending the great balloon, all the air would leave the interior balloon before any of the gas would leave the great balloon.

The first trial of my "No. 2" was set for 11th May 1899. Unfortunately, the weather, which had been fine in the morning, grew steadily rainy in the afternoon. In those days I had no balloon house of my own. All the morning the balloon had been slowly filling with hydrogen gas at the captive balloon station of the Jardin d'Acclimatation. As there was no shed there for me the work had to be done in the open, and it was done vexatiously, with a hundred delays, surprises, and excuses.

When the rain came on, it wetted the balloon. What was to be done? I must either empty it and lose the hydrogen and all my time and trouble, or go on under the disadvantage of a rain-soaked balloon envelope, heavier than it ought to be.

I chose to go up in the rain. No sooner had I risen than the weather caused a great contraction of the hydrogen, so that the long cylindrical balloon shrunk visibly. Then before the air pump could remedy the fault, a strong wind gust of the rainstorm doubled it up worse than the "No. 1," and tossed it into the neighbouring trees.

My friends began at me again, saying:

"This time you have learned your lesson. You must understand that it is impossible to keep the shape of your cylindrical balloon rigid. You must not again risk your life by taking a petroleum motor up beneath it."

I said to myself:

"What has the rigidity of the balloon's form to do with danger from a petroleum motor? Errors do not count. I have learned my lesson, but it is not that lesson."

Accordingly I immediately set to work on a "No. 8," with a shorter and very much thicker balloon, 20 metres (66 feet) long and 7*50 metres

ACCIDENT TO "No. 2," MAY 11, 1899

(SECOND PHASE)

(25 feet) at its greatest diameter (Fig. 6). Its much greater gas capacity—500 cubic metres (17,650 cubic feet)—would give it, with hydrogen, three times the lifting power of my first, and twice that of my second air-ship. This permitted me to use common illuminating gas, whose lifting power is about half that of hydrogen. The hydrogen

plant of the Jardin d'Acclimatation had always served me badly. With illuminating gas I should be free to start from the establishment of my balloon constructor or elsewhere as I desired.

It will be seen that I was getting far away from the cylindrical shapes of my first two balloons. In the future I told myself that I would at least avoid doubling up. The rounder form of this balloon also made it possible to dispense with the interior air balloon and its feeding air pump that had twice refused to work adequately at the critical moment. Should this shorter and thicker balloon need aid to keep its form rigid I relied on the stiffening effect of a 10-metre (33-foot) bamboo pole Fig. 6) fixed lengthwise to the suspension cords above my head and directly beneath the balloon.

While not yet a true keel, this pole keel supported basket and guide rope and brought my shifting weights into much more effectual play.

On November 13th, 1899, I started in the "Santos-Dumont No. 3," from the establishment of Vaugirard, on the most successful flight that I had yet made.

From Vaugirard I went directly to the Champ de Mars, which I had chosen for its clear, open space. There I was able to practise aerial navigation to my heart's content—circling, driving ahead in straight courses, forcing the air-ship diagonally onward and upward, and shooting diagonally downward, by propeller force, and thus acquiring mastery of my shifting weights. These, because of the greater distance they were now set apart at the extremities of the pole keel (Fig. 6), worked with an effectiveness that astonished even myself.

ACCIDENT TO "No. 2," MAY 11, 1899

(THIRD PHASE

This proved my greatest triumph, for it was already clear to me that the central truth of dirigible ballooning must be ever: "To descend without sacrificing gas and to mount without sacrificing ballast."

During these first evolutions over the Champ de Mars I had no particular thought of the Eiffel Tower. At most it seemed a monument worth going round, and so I circled round it at a prudent distance again and again. Then—still without any dream of what the future had in store for me—I made a straight course for the Pare des Princes, over almost the exact line that, two years later, was to mark the Deutsch prize route.

I steered to the Pare des Princes because it was another fine open space. Once there, however, I was loth to descend, so, making a hook, I navigated to the manœuvre grounds of Bagatelle, where I finally landed, in souvenir of my fall of the year previous. It was almost at the exact spot where the kite-flying boys had pulled on my guide rope and saved me from a bad shaking-up. At this time, remember, neither the Aéro Club nor myself possessed a balloon park or shed from which to start and to which to return.

On this trip I considered that had the air been calm my speed in relation to the ground would have been as much as 25 kilometres (15 miles) per hour. In other words, I went at that rate through the air, the wind being strong though not violent. Therefore, even had not sentimental reasons led me to land at Bagatelle, I should have hesitated to return with the wind to the Vaugirard balloon house—itself of small size, and difficult of access, and surrounded by all the houses of a busy quarter. Landing in Paris, in general, is dangerous for any kind of balloon, amid chimney-pots that threaten to pierce its belly, and tiles that are always ready to be knocked down on the heads of passers-by. When in the future air-ships become as common as automobiles are at present, spacious public and private landing-stages will have to be built for them in every part of the capital. Already they have been foretold by Mr Wells in his strange book, "When the Sleeper Wakes."

Considerations of this order made it desirable for me to have a plant of ray own. I needed a building for the housing of my air-ship between trips. Heretofore I had emptied the balloon of all its gas at the end of each trip, as one is bound to do with spherical balloons. Now I saw very

ACCIDENT TO "No. 2," MAY 11, 1899

(FINALE)

different possibilities for dirigibles. The significant thing was the fact that my "No. 3" had lost so little gas (or, perhaps, none at all) at the end of its first long trip that I could well have housed it overnight and gone out again in it the next day.

I had no longer the slightest doubt of the success of my invention. I foresaw that I was going into air-ship construction as a sort of life work. I should need my own workshop, my own balloon house, hydrogen plant, and connection with the illuminating gas mains.

The Aéro Club had just acquired some land on the newly - opened Côteaux de Longchamps at St Cloud, and I concluded to build on it a great shed, long and high enough to house my air - ship with its balloon fully inflated, and furnished with all the facilities mentioned.

This aerodrome, which I built at my own expense, was 30 metres long (100 feet), 7 metres (25 feet) wide, and 11 metres (36 feet) high. Even here I had to contend with the conceit and prejudice of artisans which had already given me so much trouble at the Jardin d'Acclimatation. It was declared that the sliding doors of my aerodrome could not be made to slide on account of their great size. I had to insist. "Follow my directions," I said, "and do not concern yourselves with their practicability!" Although the men had named their own pay, it was a long time before I could get the better of this vainglorious stubbornness of theirs. When finished the doors worked, naturally. Three years later the aerodrome built for me by the Prince of Monaco on my plans had still greater sliding doors.

While this first of my balloon houses was under construction, I made a number of other successful trips in the "No. 3," the last time losing my rudder and luckily landing on the plain at Ivry. I did not repair the "No. 3." Its balloon was too clumsy in form and its motor was too weak. I had now my own aerodrome and gas plant. I would build a new air-ship, and with it I would be able to experiment for longer periods and with more method.

START OF "No. 3," NOVEMBER 13, 1899