One particular undertaking was to be the source of much pleasure to me. Rumpler had just completed a monoplane which was specially designed for climbing. It now became our aim to achieve a high-altitude flight record. The famous pilot, Linnekogel, was to fly the machine, and he asked me to accompany him as observer. It was only natural that I accepted with delight.
On one of the last days in February we started on our first trial trip. Warmly wrapped up against the severe cold, we sat in our machine, and many eyes followed us with envy as our bird rose in the air with the lightness of a dragon-fly. Watch in hand, I noted the altitude, and after fifteen minutes we had already reached 2000 metres, which at that time was considered an extraordinarily good performance. But after that we only progressed slowly. The atmosphere became bumpy, and we were flung about like feathers by violent eddies or bumps. After an hour we had at last reached 4000 metres, when with a popping and spluttering noise the motor began to run irregularly, and stopped altogether after a few seconds. We now descended in spirals towards the earth, and some minutes later the machine stood unharmed on the flying-ground.
The cold had been too great, and the motor was simply frozen—a circumstance which nobody had foreseen. New improvements were promptly added. After a few days we started again on the same adventure, but this time better luck seemed in store for us. We climbed steadily and securely 4000 metres, 4200, 4500 metres. Thank God, our last record was broken! The cold was well-nigh unbearable, and I am convinced that the thickest hide would have been no protection against it.
4800, 4900 metres! 400 more and our object was attained. But the machine seemed bewitched, and refused to climb another metre! All our attempts to induce an extra effort failed. We were running short of petrol, and the engine gave out completely this time.
An altitude of 4900 metres! We landed, without a single drop of petrol, nearly frozen to ice. We had not achieved all we had set out to do; however, it was a good result. We had won, and won brilliantly, the German high-altitude record.
But success made us ambitious. At the beginning of March weather conditions again improved sufficiently to allow us to try our luck once more. More warmly clad than last time, and fitted out with thermometers, though without an oxygen apparatus, we started on our third attempt.
We reached the first altitude with ease. The sky was covered with huge clouds, the air icy. When we rose through the bank of clouds into the glorious sunshine we had a beautiful experience. We suddenly saw a radiantly shining Zeppelin, which was likewise attempting a flight at high altitude.
What a marvellous meeting—3000 metres up in the air! Far away from toiling humanity, high up above daily strife and pain, the two birds of the air—striking evidence of Germany’s strength and enterprise—saluted each other.
We flew several times round our big brother, and waved our hand to him in friendly greeting.
But after that we had to apply ourselves seriously to our task and work strenuously in order to attain our objective. After an hour we had gained an altitude of 4800 metres, after that 4900, my barograph soon showed 5000, and the propeller hummed its monotonous melody. Linnekogel veered quietly and methodically. The thermometer rose to 37 degrees Celsius; but we paid no attention to the cold. Only the air became rarefied. A slight sensation of drowsiness came over me, and my lungs only functioned in quick, short gasps. Every movement became irksome. Even to turn round towards the pilot who sat behind me seemed a huge effort.