an effect have a sufficiently great effect on thisship to give it as much as six hundred forty pounds of thrust?"
"Again, I should have to check the math, captain, but I would assumeso."
"Mr. Blackhawk," the captain turned to his engineer, "could such athrust throw Hot Rod off her communications beam and cause lastnight's disaster?"
"I guess I'd have to check by math, too, captain...." Mike appeared todebate the question. "It would be a very small acceleration at first,of course," he said, "from six hundred forty pounds of thrust. But HotRod's cable is slack, and the velocity needn't be great to give itquite a jolt when the slack was taken up. Yes, I feel sure that couldhappen, captain."
The captain relaxed a little, and a half-smile played near the cornerof his mouth as he said to Mike, "I believe, then, we may have foundthe _real_ saboteur, Mr. Blackhawk." Then to Ishie. "Doctor, I believethat your field is the one in which the most experience lies towardsfinding a means for counteracting the effect that is now influencingour orbit. I am putting you in charge of the problem. The pull,according to the computer, is as I said, six hundred forty pounds. Doyou think you can work out a method for counteraction?"
"I think ... possibly, yes, captain. Let me say, probably yes."
"Then please do so, and report the method to me. I will then submit itto the other scientists aboard that may have some selective knowledgein the field, and to Earth. You may, of course, call on any of thepersonnel of the ship for assistance, and possibly Mr. Blackhawk maybe of assistance to you. He is familiar with the equipment aboard.
"You probably recognize the urgency of the problem so I shall notattempt to underline that urgency further, other than to say that itis of the utmost importance," he ended.
* * * * *
Five minutes later the two conspirators were back in the engineeringquarters, grinning like Cheshire cats, and mentally rolling up theirsleeves to go to work. They had, to all intents and purposes, carteblanche to work out the construction of the device they would need foran enlarged Confusor with a real thrust, even though they would haveto appear to co-operate with a multitude of other interested parties.Mike and Ishie were both becoming adept students of the mythical Dr.Confusion, and neither doubted their combined ability to handle thatpart of the problem.
"Now," said Ishie, "Confusion say he who can fly on wings of mosquitofly better on wings of eagle. How much thrust do we want, Mike?"
"What are our limits?" asked the practical engineer.
"Limits, schlimits. We got _power_. Of course," he added, "we _are_limited by the acceptable stress limits on the wheel, and ... yes ...by the stress limits on our plastic, too."
"The wheel was designed to stand upwards of 1.5 gee maximum spin--butthat's only radial strength," Mike began figuring. "Don't thinkanybody ever calculated the stress of pulling the hub loose, endwise.No reason to, you know, and it wasn't expected to land or anything.And really, nobody expected it to stand in service more than a 1.5 geespin on the rim. They computed these racks to take all kinds of shock,but the overall structure is rather flimsily built." He paused forthought. "We could maybe put a tenth of a gee on the axis, but Ibetter check some of the stress figures against the structural patternwith the Cow first. We'll have to give some thought to strengtheningthings later, if we really want to go into the fantastic possibilityof landing this monster anywhere."
Consulted, the Sacred Cow computed a potential maximum stress-safetyat the hub of something over two-tenths of a gee, and the two finallysettled on one-tenth as well within the limits.
"Now the other limit," said Ishie. "This little piece of plastic willonly stand a pressure approaching the point at which it begins todistort and run out of the field. This stuff is quoted to have acompression-yield strength of one hundred ten pounds to the squareinch. We probably shouldn't exceed ... hm-m-m ... ninety pounds. Let'sget the Cow to tell us how big a chunk of surface area thatrepresents."
The answer was discouraging. Mike rapidly converted the figure incentimeters to feet, and came up with nearly an eighty-three footdiameter for a circular surface.
"Looks like we'll have to put it out on the spokes," he muttered indisgust, but Ishie shook his head quickly.
"No need, Mike. Later on we'll need a few thrust points out on the rimfor good aiming, but we don't have to have all this surface area inone unit or even in one place. Also, we do not need to consider onlythe surface of an homogeneous piece of plastic material.
"This plastic can be cast. Very easily. In it, we can insertstructures that will absorb the strain from many surfaces within,rather than only on a front surface.
"I expect some of the glass thread with which the hull of the ship wasmade could be inserted with no trouble. Each thread, then, would takeup the strain, and a mass of them distributed through the plasticcould deliver a greatly increased amount of thrust from a volume ofplastic rather than from a surface area."
* * * * *
Mike started to object. "To get an absolutely parallel magnetic field,the gap between the pole faces can't be very wide."
"Perhaps I wasn't considering pole faces," Ishie answered. "Ourinvestigation has already shown that once initiated the thrust-effectworks best in a very low magnetic field.
"Such a low, parallel magnetic field would quite probably be foundinside of a simple solenoid coil."
"O.K.," Mike answered, "but you have also found that a very highmagnetic field is required to initiate the action. How do you get thatinside a solenoid without an iron core?"
"As you say, a strong field must _initiate_ the action. Let us tryanother experiment, Mike."
Ishie turned the Confusor off, selected a piece of wire from Mike'ssupplies, and wound a ten-turn coil over the large magnetic coils ofthe experimental device.
The leads from this he ran to a pulse-generator that could beaccurately adjusted to supply pulses of anything from a tenthmicrosecond to a tenth second.
Selecting the shortest possible duration, he then set the magneticfield adjustment on the experimental device to a point just below thatpoint on which it had turned on previously.
"Now we see." Turning on the device, he glanced at the display panelwhich still showed zero thrust. Then he triggered a singleone-microsecond pulse into the additional ten turns of winding. Thereadout display showed zero thrust. He triggered a ten microsecondpulse. Nothing happened. One hundred microseconds. Nothing. Onethousand microseconds--the display changed, dropping so quickly intoposition that the pulse thrust itself was not recorded--but the figureturned up seven hundred thirty pounds thrust on the display panel.
"So," said Ishie, "we can initiate thrust with a one thousandmicrosecond pulse. Can you design a power supply that would achievethat field for that time in a solenoid having ... say ... one per centas high a field strength as the one we are using here?"
"O.K.," said Mike. "I get you. Sounds to me like this thing is goingto look like a barrel when we get through with it.
"I wish," he added, "that we could get one point one gee. And landthis thing on Earth. And have a big parade, with Space Lab Onehovering just overhead to the cheers and the blaring bands and the--"
"Confusion say, he who would poke hole in hornets nest had best beprepared with long legs." Ishie grinned. "You don't think anybodywould really appreciate our doing that, do you Mike? Outside of thepeople themselves, that is, that aren't directly concerned with man's_welfare_? We haven't done this in the proper manner of team researchand billions spent in experiments and planned predicted achievementsmade with the proper Madison Avenue bow to the financier that made itpossible. You know what they do to wild-haired individualists downthere, don't you?"
Mike shrugged. "Oh, well," he said, "you're right of course. But itwas a beautiful dream. How do you suppose we can build these and stillkeep all the scientists aboard and on Earth happy that they're justinnocent magneto-ionic effect cancelers? Boy, that was a beauty,Ishie!"
"Best we have two sets of d
rawings. The ones for us can be sketchy,and need not have too much exactitude of design. We know what we'redoing--at least, I hope we do.
"But let us make a second set of drawings that is somewhat different,though of a simpler shape and design, on which other scientists aboardcan speculate, and which can be sent to Earth to confuse theconfusion."
* * * * *
The two went to work with a will, and as the two sets of drawingsemerged, they were indeed different. The set from which they wouldactually work was only mildly described as sketchy. The papers lookedlike the notations a man