That was what the low-tech simulators that had sprung up since the Belle had first flown were about, letting you practice before climbing into one of the still few planes that had been completed since the Belle's first flight. Flight time in those was very expensive. The Belles were unavailable, strictly for the military. Kelly Aviation usually had one plane running, well, sometimes. In general, Mr. Kelly would finish it, then a few days later take it apart for parts for the next one. But during those times when one of his planes was in fact flight ready, you could take flights in it and even get flying lessons. For the paltry sum of two hundred fifty dollars an hour.
The Kitts had an airplane and mostly kept it running. It was a two-seater, front and back, and lessons were three hundred dollars an hour. Over the two months that Giuseppe and Gemma were occupied in building the model, Krause racked up over a hundred hours in various simulators, forty hours of ground school, reading maps from the air and such, and a grand total of seven and one quarter hours in the air. He thought he knew how to fly, not well perhaps, but well enough. Besides, he was spending a lot of money on flying lessons.
****
It was in the days before the model was ready for the wind tunnel that the secrecy, which had been more a matter of habit and general caution, became a matter of vital necessity. Hans Richter flew into history and John George into insanity within days. In response to the change from the CPE to the USE, John George and and the Elector of Brandenburg had withdrawn from the Swede's alliance. John George had never been the most popular neighbor to the up-timers, but now he was considered a traitor by the king of Sweden and at least a potential threat by the Americans. Building an airplane nominally for John George would be seen as an act as hostile as building the plane for Cardinal Richelieu. Possibly more hostile. After all, John George was closer. It made no real difference in Willem Krause's plans. He had always been careful about such things. Because if no one knew who was paying the bills, it would be harder for them to come in at the last minute and take away his airplane. Now, keeping them in ignorance would be essential to keeping the project going.
"I lost another commission today," Pierre Trovler told Willem dejectedly "Because I'm French. I'm not a cardinal or a politician. I'm an artist."
"You have my sympathy, my friend," Willem told him. "As long as you don't expect me to express it too loudly. People are excited by boys at Wismar and incensed by the League. I suggest you don an appropriately patriotic mien. Perhaps a painting of the heroic outlaw driving into the enemy ship. Or, you could join the CoC. I'm just grateful no one is asking where I was born, since my family's estates are in the electorate of Brandenburg."
"I'm already a member of the CoC," Pierre told him. "I was before this happened."
"Really? I wouldn't have thought you were the sort. Didn't you just say you weren't political just after you disclaimed being a cardinal? Do you paint in red robes?"
"You don't have to be a cardinal to be Catholic and you don't have to be a politician to believe in liberty. I know you're of the nobility, but you're a regular guy, not like John George."
Willem gave no sign by word or action that anything had changed but something had. For while he was in no way John George and cordially despised the man, neither was he a regular guy. He was of the nobility and that made him different from peasants of any situation, no matter how grand their circumstance or how mean his. He was of the nobility. His genial manner was just that-a manner. He stepped down from his natural station to put people like Pierre at ease and get the best labor out of them, not because he thought them his equal. But here they thought they were-even normally sane people like Pierre. He would have to be more careful now.
****
Willem watched as the technician attached the thin steel wires to his model airplane. One from the top of the model, set at the center of gravity, went through the top of the wind tunnel, over and around a pulley, off to another pulley, then down the side to a weight and gauges for reading. The bottom center of gravity wire went down through the bottom of the wind tunnel to an adjustable spring.
There were similar sets of wires at the nose, center, tail, and wing tips. Together the wires and gauges would measure the lift and drag of the airfoil at varying wind speeds and at various flap and aileron settings.
Then they started the fan and the model Arrow was pushed back by the wind. The technician took measurements: lift at nose, lift at tail, drag-each measurement taken several times, once for each air speed. The process was repeated with smoke and more notes were taken, when the smoke started swirling and where on the wing. Then the fan was turned off and the flaps were adjusted, and the process started again. After they were done, they had the Reynolds number by working backwards from the point of non-laminar flow.
That, and a whole lot more data that could be fed into a computer spreadsheet program to give solid estimates of lift and drag over a range of speeds and angles of attack. They added weights to different points on the model, adjusting its center of gravity to include the weight of things like engine and pilot. Maneuverability, carrying capacity, takeoff speed, and more, were provided by the wind tunnel tests of the model in combination with the knowledge bought by thousands of lives over a hundred years in that other timeline. It seemed to Willem complete, and offered a level of confidence that surpassed that even of shipwrights. And compared to what the Wright boys, Curtis, Sikorsky, or even Douglas had had to work with, it was complete.
****
It took a few days to process the data. Well, it took a few days to get around to processing the data. It took a couple of hours to input the data and the computer took microseconds to do the calculations. And it didn't take Hal Smith much longer to interpret the results.
The faster the plane was going, the greater the lift. As was standard but, like the weight, the lift was centered well back on the plane. In fact, even at fairly low speed, the center of lift was farther back than the center of gravity, which meant that in flight the Arrow was going to be nose heavy. Because of ground effect, that was even more of a problem on takeoff and landing. Because the ailerons were actually elevons, combining the function of both elevators and ailerons in one control surface. And because it was a tailless delta, you couldn't go flaps down for takeoff and landing. Not without shoving its nose into the ground. So they would need to shift as much of the heavy bits as they could toward the back of the aircraft.
****
He discussed his changed designs with the boy Darius because he had been the researcher for the whole project. "Herr Smith doesn't much care for the delta-wing design," Willem told Darius with another of his half-grins. He had just returned from a very expensive half-hour consultation with the only aeronautical engineer on earth. When not working for the State of Thuringia-Franconia Air Force, Hal Smith-for a piddling five hundred American dollars an hour-did consultations with prospective aircraft designers. And to spend that five hundred dollars an hour, you made an appointment and waited your turn.