Synopsis: No one can always be correct. No living thing is above mistake. No living thing, so no one thought to apply the this idea then, for the one in question had no life. However, even it could make a mistake, after all it was man made. Subject to human error, only as accurate as it's once living creators had made it.

What would happen if AIVAS miscalculated, and thread did return? Who would be left to save Pern if a tenth pass started?

Disclaimer: I do not own the Dragon riders of Pern books.

A/N: This is my first time writing a fiction for this series… or for any book at all. This is also my second story up on fan fiction, not including the joint one I have up on another account. I hope you enjoy. This is likely going to be one of very few A/N's you see from me in this story.

This is the re-written version of the prologue.

AT= After the last Thread fall.

Ferelan's Farm hold- this location will later be referred to as Fedrier's Farm hold.

Prologue:

1291st turn AT
Feralan's Farm Hold

A small boy with black hair woke with a start. He just had a feeling that something was going to happen. Not long after, he heard someone pushing the door to his small room open. He looked up towards the door to see his mother, her face tear streaked. He was on his feet before she had a chance to tell him what was wrong. He already knew. His grandfather was dying. They'd been expecting it all summer.

He made his way to the door as his mother stepped back away from it. Slipping out of his room, he took the few steps that were needed to reach the room were his grandfather rested on a narrow cot. The old man had refused his mothers offer to take her own, larger cot. He couldn't really understand why... the small cot must be terribly uncomfortable for the old man's aching body. He'd even offered the man his own cot, which wasn't that much bigger than the one he laid dying on now.

The boy moved to the chair that was near the cot, pulling himself up into it. He watched as the man's nearly blind eyes searched him out. When it appeared the man couldn't quite discern who it was sitting next to him, he grabbed his searching hand. "Grandfather," he spoke clearly, knowing that the man's hearing was failing him. He was trying not to cry, as his grandfather had told him many times not to cry over the last sevenday. It was hard though, not to cry. In his child's mind, you cried when you were sad, and that was just the way it was supposed to be. He had learned, though, that things were seldom how they were supposed to be.

"C'mere boy, a little closer," the old man pleaded, his voice weak and wavering. The boy was sure that the man could not hear his own voice. He slid from his seat to push it closer to the bed before he climbed back into the chair, taking the ailing man's hand again.

"I'm right here grandfather," he told him, having trouble keeping his voice loud enough for the nearly deaf man to hear him. He watched as the elderly man's eyes closed and his breath hitched when they did not reopen for several long minutes. He would have thought the man had died, if it had not been for the barely perceptible rise and fall of his chest. It seemed he had just been gathering his thoughts and energy so he could speak again.

"Now you listen here son, and let me tell you the tale my grandfather told me." The boy obviously wanted to protest, his blue eyes all puffy, but instead he nodded obediently. "Good boy," the dieing man murmured, before he started his tale.

107th turn AT
Landing

It had been over a hundred years since the last thread fall, but very few Pernese dismissed its existence. They had what they could consider hard evidence. The fact that Dragon's did indeed exist, and the records of thread fall, on skins, in computer databases, or on sheets of paper... which was still a rare thing on Pern. However, even though the vast majority believed thread did exist, they were also firmly set in the knowledge that it would never again fall on their planet. None of them could even begin to fathom the possibility AIVAS had been wrong. It was just not possible. AIVAS was a machine, not subject to the errors of the human mind. It was just impossible for thread to ever fall again.

So in those hundred years, people had begun to spread out slowly from their holds to settle the rest of Pern. Though the major holds remained great centers for education and many events, they became less important to the people of the planet. As people no longer feared thread, they were free to travel about the world how they pleased. Many would make their way to the southern continent and to Landing, some just to see the sight of the great AIVAS. Others went because that was where the computers were, or because it was the greatest center of education on all of Pern.

But the computers would not last forever. They had no one with the skills to make replacement parts and very few of the materials they would need anyway. So when a number of computers broke down due to various causes, the people of Pern decided to copy out all the information they found important by hand. It became a great project on the planet, and many more people flocked to Landing in order to be a part of it. The copying of the data from the computer databases became something every Pernese aspired to do at least once in their life time, as it has been for twenty turns now.

This was why they were there now. He had arrived a day ago with his sister, and both of them sat in front of one of the still working computers. They were currently sifting through files to find ones that were not flagged as copied, and were not being taken down by others. In doing so they came across a file that most would have found rather unremarkable. However, when they realized that what they were looking at were the actual calculations made by AIVAS in order to rid the planet of thread, they were keenly interested. Choosing it as their bit of file to copy, they began meticulously writing out the values and equations that the file consisted of.

While doing so they both came across a figure that somehow seemed off in their minds. Using the computer, as well as working it out by hand, they ran over the entirety math to find that the number was indeed wrong. It was something everyone had thought impossible. They themselves could not believe it. How could a machine be wrong? Unable to believe it, they worked it out several more times, only to end up with the same results. Deciding to leave it for the time being, they both set back to copying out the figures that appeared on the screen before them.

They took turns sleeping during the night, neither having any desire to leave the computer and potentially lose the file they were copying. They finished shortly after dawn, and decided to go over it all again to make sure. That one figure kept bothering them, and they again checked the math, to once more end up with the same results. Once they had no doubt left that the figure was indeed wrong, they decided to bring the matter up to others, whom had more background in mathematics then they did. Still not wishing to leave the computer alone, the sister went alone to find these people, while the brother stood guard over the computer.

Next day

The sister found that most were not interested in taking a look at the equations, not believing there was any chance AIVAS could have made a mistake. However, by noon of the next day, she finally found a group who were of the private opinion AIVAS was not above human error. After all, the super computer was made by humans. When she brought the matter up to them, they jumped on the chance to prove themselves right. So they all went over to the computer, checking over the copied numbers, as well as the numbers on the screen. When they worked it out several times to achieve the same result as the siblings, all present were convinced. AIVAS had made a critical mistake. Thread could possibly return to ravage their world again.

There was only one thing for them to do at that point. Finding themselves a quiet building at Landing, they worked through the numerous equations to find the real ending values. They even went as far as to find out exactly how far they had sent the red planet out of its original orbit. What they found was even more startling then the fact that AIVAS had made a mistake. By taking in the forces of gravity on the various bodies around their star system, they had come to the conclusion that thread would return to Pern. It would take somewhere around another twelve hundred turns, but it would return.

This was a problem. In twelve hundred turns Pern would still be thoroughly grubbed... unless something happened to kill off all the grubs... but people would be spread out, likely not believing in thread, and be ill equipped to deal with it. Unless they knew it was coming. Again, the group was left with one clear choice. Announce their findings to the rest of Pern.

1291st turn AT
Feralan's Farm Hold

The boy looked at his grandfather for several minutes, rather perplexed. Had the old man finally lost his mind in his dying moments? "But Grandfather, everyone knows thread won't fall again." In fact, he would go as far as to say most children didn't even know what thread was. The only reason he did was because it was one of the things his grandfather loved to talk about. He had never thought the old man would go as far as saying it would fall again though. That was just... why, impossible!

The old man didn't seem to share his opinion though. After going into a dry fit of hacking, he held up his other frail had for silence. "Quiet boy. Give me a moment... I'll explain it," he managed to wheeze out, before taking several minutes to gather his strength again. "Thread will fall again, and knowing this they announced it to the rest of Pern...

107th turn AT
Landing

...but nobody believed them. They brought their findings to many learned men, with very little luck. Most said 'How could that be? AIVAS is above the human mind.' However some found it curious and made a trip to Landing to take a look at the equations. When these men, and a few women, could not prove the new figures wrong, some began to believe. However, others accused them of fraud, seeing the whole thing as a huge scam. Many such people attempted to get their hands on the papers with the AIVAS equations. Some to prove the group of men and woman wrong and others simply to burn them.

The papers were kept at Landing, were at least two from the group were always present. However, despite all the precautions they took to keep their findings safe, in the end they could not. A couple of the non believers set the interior of the building on fire while the five present slept. Only two managed to make it out with their lives, while the other three died in the attempt to save their evidence of thread returning. With no evidence it would be a struggle to even convince one person to believe them, let alone a whole planet. They nearly gave up hope on saving the Pern of the future... after all, why should they bother? They wouldn't live to see it.

Three Sevenday Later

As the days went by, and they were ready to call it quits, they had an unexpected stroke of luck. A middle aged bronze Rider by the name of D'tul, and a gold Rider by the name of Minessa got word of the incident in their secluded southern home. It was the first they had heard of 'thread's return', and the idea intrigued them greatly. Together, with their children, the spoke to other riders whom they found of like mind. The number of Dragonmen, and women, who found the idea plausible was rather shocking to them. When three sevenday had gone by, they approached the group who made the discovery, expressing their interest in the matter.

The group of believers had found it quite a shock, but they jumped on this last opportunity that had been given them. If they could convince these riders beyond a doubt that thread would return, then perhaps they would have the needed dragon riders to take the steps that would save Pern's future. They found this task surprisingly easy, and within the next sevenday, the riders had all gathered at Landing.

The fact that so many Riders believed thread would return attracted attention once more. Those who did not believe were too afraid to act openly against them, considering the number of dragons that were always in attendance. As their group steadily grew in size, they set about trying to decide the best course of action to take. Many wanted to bring it to the public once more, but the Gold Rider Minessa had another idea. Announcing their belief that thread would return had already failed once, and would likely fail again. They could try and slowly convince the general population to believe them, but as more time went by, that task would prove impossible. In her eyes, there was only one logical solution to the problem.

To go Between times twelve hundred years, insuring that when Pern once again had to face the threads, she would be ready.

Every rider agreed.

So that was exactly what they did. After extensive planning and gather of supplies, one hundred and fifty great beasts took to the air above Landing, and disappeared between, taking with them some candidates, as well as some to staff the Weyrs when they arrived in their destination time. They left behind many of the non riders, giving them the task of spreading the knowledge thread would return among the population so there would be supporters for them when they finally broke the sky above one of the already dusty Weyrs in a startling array of colors.

1291st turn AT
Feralan's Farm Hold

"Our ancestors were some of the folk left behind to tell that tale son," the old man murmured weakly. His voice had weakened almost to the point that the boy could no longer understand a word he was told. "I don't know how many others there are still, but I do know this boy." He would have gone on, but wavered as his wrinkled face tensed in pain before he was sent into another fit of dry hacking. His breaths were short, shallow, and caused his whole body to shake. Yet he pushed through the pain, the need to impart his message pushing him to continue. "With my dieing voice I have to tell you, listen here boy," he sputtered, before licking his lips weakly and trying to find his voice once more. "Heed this....they'll come before you die, before… you die." His voice was beginning to waver out nearly completely and the child had to lean in closer to catch the next words. "When I die... there won't be any dragons left.... promise me … you'll believe… they will... come." The word come came out in a mangled breath before the old mans glazed over eyes rolled back into his head and he fell limp against the narrow cot. His hand slid out of his grandsons small grasp to hang limply beside the cot.

The boy sobbed. "I promise! I promise!" he cried again and again, even as he heard the hysterical screech that came from the blue dragon just without the hold. Still sobbing, he pushed himself off the chair to make his way over to the window. He reached it just in time to see the old blue dragon launch itself into the air with another cry of protest, before it sought out the refuge that was between, never to return again.

And so the ten year old Fedrier witnessed the death of his grandfather and his dragon, supposedly the last Dragon and Rider Pern would ever see. But the boy knew the old man was right. Dragon's would return.