Ho I Trial Flights

These started in July 1933 at the Bonn-Hangelar airport. Like our models before, the glider was launched with a bungee cord, resulting in glides of 150 to 300 feet at altitudes of six feet or less.

 During these tests it was established that the central elevator location was quite unsatisfactory, as it would change the airfoil and washout with each movement, sometimes with surprising results. The Haps-effect of a down elevator caused us to remove forward trim weights, which almost doubled the gliding distance. But it also set the stage for dangerous reversal of elevator response.

 The tests continued with car tows to 100 feet altitude, and straight glides. Now we discovered that application of aileron caused a strange level skid, instead of the desired bank!

 The drag rudders also responded differently than conventional rudders. The latter causes the aircraft to move a certain amount in response to the input, then stop. In contrast, our flying wing kept turning until a short application of opposite rudder was given. We ended up turning the aircraft by the drag rudders alone, and found that the resulting skid produced the necessary bank. This discovery led us to try a 1000 It winch launch, and fly back to the starting point.

 The aileron problem was finally solved by enlarging them, and increase their up travel to the point that the airflow under the up aileron separated, and created the necessary compensating drag.

 We were now ready for the first aerotow. Walter towed to 3500 feet, and after releasing from the Me 23, glided down with gentle turns. During the landing, the elevator reversal became evident again, and the aircraft suddenly nosed into the ground during flare-out. Fortunately, it was only slightly damaged.

 The elevator reversal/ problem was eventually solved by moving the c/g forward again, so that less down elevator was needed, and the flaps effect avoided.

 The following summer I was approached by the District Chief of our National Aero Club. He wanted me to demonstrate the glider at the upcoming air show at the Bonn-Hangelar airport in June. My test program had progressed very slowly, since I was still in school, and had limited funds to pay for tows. I agreed after obtaining a promise of free aerotows to complete my tests, and an airworthiness permit to compete in the Rhone contest the following month.

 I was unable to get out of school during the first week of the contest, but the second Sunday found me all set for the aerotow over to the Wasserkuppe contest site. My brother Walter was on his last day of military leave. He had managed to borrow a Klemm 25 towplane, and was taxiing out to the runway when the Airport Police informed us that our takeoff clearance was denied. The reason was that a squall line was approaching from the west. The fact that we were heading east failed to impress the authorities, and the aircraft were returned to the hangar.

 At 2 PM, after the front had passed, came the permission to depart. Soon our two machines, connected by a 300 ft. steel cable, had overtaken the squall line. We Hew low in the valleys to keep out of the clouds and avoid lightning strikes. The turbulence was terrifying, and at times I was unable to see the Klemm! We finally broke out over Vogelsberg and could see the Wasserkuppe ahead. I released and headed for the west ridge while Walter reversed course and disappeared, to catch the night train back to his base. I spotted a Grunau Baby at about 600 feet and headed for it. I was anxious to test the performance of my glider against this new design, but severe fatigue from the turbulent flight soon overcame me, and I turned towards the landing area. As I turned final over the Worstensachsen road, I saw to my dismay that I would be landing short! The skid hit an invisible rock, and splintered with a sickening crunch!

 So, there I was on the "Kruppe", with a damaged glider and no crew . . .

 It was Wednesday before the glider was repaired and a new permit issued. The contest ended on Friday, so with little chance of accomplishing anything, I called up DFS in Darmstadt and talked to Alexander Lippisch. I told him what had happened, and offered him the glider for free, if he would send a towplane to tow it to Darmstadt. Lippisch said that was not possible.

With no chance of a place in the competition, I got a launch on the west ridge, and struggled over the unfamiliar terrain until I had sufficient altitude to fly over to the other side, where I landed near the south ridge.

The H I earned us a "Construction Price" of DM 600, but no financial support was promised for our next project.

 A week later the glider school Director ordered me to remove myself and the glider from the Wasserkuppe. I made one last "farewell" flight in the H 1, then I dismantled it, and burned it the following day.