A particularly broad program was the development of synthetic training devices and synthetic testers. Both faced the problem of reproducing as accurately as possible the circumstances under which certain vital components would operate, and also those which would affect the humans who would take part in the expedition.
Synthetic testers were typified by the control simulating device. The weight of the Mars vessels would be reduced from 3,720 tons to almost 50 tons during the voyage, by the exhaustion of propellants, and this reduction in weight would reduce the so-called mass moment of inertia, profoundly affecting the operation of the automatic controls. The control simulating device permitted an accurate laboratory test of the functioning of the control mechanisms under a broad variety of operating conditions. This would greatly reduce the risks attending any mechanical malfunction or some unpleasant surprise or other in the physical behavior of the control gear during the voyage itself.
In order to study the behavior of the control system on such a device, the oscillationsusceptible system of the automatically controlled ship was simulated by a complicated electronic hook-up. This permitted an exact determination of the way an initial angular displacement impressed upon the vessel would be corrected by the automatic controls. It would show whether the attitude adjustment was rapid or deliberate, whether or not there was over-correction, and how many corrective oscillations took place; or finally, whether the controls might throw the ship into that dreaded "flutter" which might break it to pieces.
At the same time, the control simulating device afforded a splendid means of regulating the control mechanism to its most favorable setting for each of the greatly variable operating conditions.
The synthetic training devices, on the other hand, were evolved with the idea of giving to the crews advance preparation in meeting and overcoming the problems they would meet on the voyage, even before it started.
There were special training devices which duplicated the entire electrical system of the Mars vessels. These were especially for the training of the troubleshooters. Such devices afforded a field for the malicious talents of the instructors, in that they could produce intentional malfunctions to test the ingenuity and handiness of their victims.
They might tear a single wire out of one of the hundreds of jack plugs or shove a burned match between the contacts of some inconspicuous relay. Stop watch in hand, they stood around the great masses of wiring and switches while the troubleshooters labored to find and repair the defect in the shortest possible time.
Then there was a complete, working mock-up of the air and water regeneration plant.
Here the routine maintenance jobs, such as filter cleaning, gasket changing and valvereplacing, could be practiced. The more serious malfunctions were, of course, not neglected, especially those where speed of repair was of the essence. The crews were trained in blower troubles, "no juice" problems, defects in the water pump of the carbonic acid absorption tank, plugging of the oxygen supply and similar emergencies which might make the air unbreathable. Each and every emergency could be synthetically reproduced in all its natural horror.
There was also a synthetic flight training device for the landing craft crews. It consisted of a pilot's cockpit from a landing craft, complete with all instruments. In it the pilot and his helpers could undergo the whole gamut of the landing procedures from the departure out of the orbit to the touch down. Here they could be trained in coordinating altitude and speed. An elaborate electronic flight path simulator on the instrument panel accurately reflected the craft's response to control movements. Even a Martian landscape was portrayed on the rolling carpet that passed before the eyes of the pilot as he synthetically flew along.
The presentation piece among the training devices was the "Command Post." It consisted of a complete personnel nacelle of a passenger vessel situated centrally in a specially-built planetarium. A practice run in the Command Post was almost uncanny in the verisimilitude with which it reproduced the conditions under which the crew of a Mars vessel would some day work and live and have their being.
Of course the pilot's cabin was equipped with the same maze of operating panels, warning lights, gauges and radios as the actual cabin. Through the astrodomes could be seen the brilliant reaches of the firmament. The Sun, the Earth, the Moon, not to mention Mars with his dual attendants, could be projected in any desired dimensions upon the dome of the planetarium. They and the other planets could be made to move against the background of the fixed stars.
No crew ever went through the dry run of the voyage which this simulator offered without being deeply affected. The difficult final maneuver, the maneuver of adaptation upon return to the terrestrial orbit, when practiced in the simulator, took place as follows.
The great, sunlit shape of the Earth's sphere appeared on the velvet-black backdrop of the planetarium's dome. As the vessel gradually drew nearer, accompanied by an accurate portrayal of the increasing velocity, this great shape covered and uncovered various fixed stars as it moved along, seeming to grow in size to the eyes of the anxious navigator as he lay within his astrodome. He measured the angle between Earth and certain of her neighbor stars, thus getting a fix from his precomputed parallax tables.
Chronometer in hand, he read the seconds at which certain of the stars near the Earth's rim were obscured by it and compared these times with what they should have been according to his tables. Then, as a check, he made a parallax measurement on the Moon. When he was satisfied with his observations and had good coordination between his fixes as found by different means, he would again consult his tables and then, through the interphone, would pass on to the Command the complete data on how to set up the necessary maneuver for entering the orbit of arrival.
The Captain would then aim his two telescopes, mounted on the gyro gimbals, at two reference stars on the dome of the planetarium and fix their positions by means of his photocells. He would set the course the navigator had given and start his gyros and flywheels. But where the course change would have turned the ship in reality, here it was the planetarium that moved around the nacelle, causing the entire firmament, Sun, Moon, Earth and stars, to parade across its dome so that it appeared that the "ship" was acquiring its new attitude in space. Finally, when they had reached the position called for by the ship's new attitude, the motion stopped and the navigator would continue his observations from one of the other astrodomes.
When the time came to apply thrust, the preparatory motions and the maneuver itself in the simulator called for exactly the same manipulation of switches and levers as inactuality. The same warning lamps flashed, the same gauge hands trembled over their dials as though the flight were real. Even the muffled thunder of the rocket exhaust could be heard. Dim and distant, it would only reach the occupants by transmission through the metal parts of the ship, for the vacuum of space cannot carry sound.
But there was one control panel in the mock-up which in reality would be absent. Behind it sat John Wiegand with a diabolical grin on his face. He could hear distinctly the piteous conversation between the Engineer and the Captain as he produced instrument readings on their panels calculated to drive them to desperation. Hearing their planned corrective measures, he could block their success by a turn of the wrist. One after another, he conjured up malfunctions to plague them. Suddenly, in the midst of a power maneuver, the respiration blower might stop. One of the four motors of the steering gear would show suspiciously high amperage. The worst and emotionally most disturbing trick he would play would be to indicate on several instruments simultaneously a malfunctioning of the main rocket motor. This would include a most lifelike imitation of stuttering or howling in the otherwise steady growl of the exhaust. Then there was a matter of only seconds in which the captain had to do the right thing or else endanger the entire vessel.