A few days ago my friends told me about a sci-fi book where a group of future humans drop their ship out of FTL above a planet and descend to the surface in a small lander, shortly before having the anti-gravity drive overload and vaporise, destroying the lander and stranding them. Apparently the team cooperates with the planet's medieval era civilisation to reinvent rocketry and chemical propulsion to try and get back into orbit. Unfortunately however, none of my friends can remember the name of the novel, and I was wondering if anyone here could help me?
"Star Ship", not a novel, a novelette by Poul Anderson, in his Psychotechnic League series; first published in Planet Stories, Fall 1950, which you can read for free at the Internet Archive. Your friends might have read it in Space Odysseys, a 1974 anthology edited by Brian Aldiss.
. . . a group of future humans drop their ship out of FTL above a planet and descend to the surface in a small lander, shortly before having the anti-gravity drive overload and vaporise, destroying the lander and stranding them.
"We were ten, all told, five men and their wives. Exploratory expeditions are often out for years at a time, so the Service makes it a policy to man the ships with married couples. It's hard for a Khazaki to appreciate the absolute equality between the sexes which human civilization has achieved. It's due to the advanced technology, of course, and we're losing it as we go back to barbarism—"
[. . . .]
". . . we'd been a few weeks out of Avandar—it was an obscure outpost them, though I imagine it's grown since—when we detected this Sol-type sun. Seeing that there was an Earth-like planet, we decided to investigate. And since we were all tired of being cooped in the ship, and telescopes showed that any natives which might exist would be too primitive to endanger us, we all went down in the lifeboat.
"And the one-in-a-billion chance happened . . . the atomic converters went out of control and we barely escaped from the boat before it was utterly consumed. We were stranded on an alien planet, with nothing but our clothes and a few hand weapons—and with our ship that would go faster than light circling in its orbit not ten thousand kilometers above us!
"No chance of rescue. There are just too many suns for the Galactic Co-ordinator to hope to find a ship that doesn't come back. Expansion into this region of space wasn't scheduled for another two centuries. So there we were, and until we could build a boat which would take us back to our ship—there we stayed!
"And it's taken us fifty years so far. . . ."
Apparently the team cooperates with the planet's medieval era civilisation to reinvent rocketry and chemical propulsion to try and get back into orbit.
The stranded Terrestrials had found themselves in an early Iron Age civilization of city-states, among a race naturally violent and predatory. For their own survival, they had had to league forces with the state in which they found themselves—Krakenau, as it happened. Before they could build the industry they needed, they had to have some security—which meant that they must teach the Krakenaui military principles and means of making new weapons which would make them superior to their neighbors. After that—well, it took an immense technology to build even a small spaceship. The superalloys which could stand the combustion of rocket fuel required unheard-of elements such as manganese and chromium, which required means of mining and refining them, which required a considerable chemical plant, which required— How far down do you have to start? And there were a hundred or a thousand other requirements of equal importance and difficulty.
Besides, the Terrestrials had had to learn much from scratch themselves. None of them had ever built a rocket ship, had ever seen one in action even. It was centuries obsolete in Galactic civilization. But gravity drives were out of the question. So—they'd had to design the ship from the ground up. Which meant years of painstaking research . . . and only a few interested humans and Khazaki to do it. The rest were too busy with their own affairs in the brawling, barbaric culture.
Ten years ago, the first spaceboat had blasted off toward the Star Ship—and exploded in midacceleration. More designing, more testing, more slow building—and now the second one lay ready. Perhaps it could reach the Star Ship.
The Star Ship—faster than light, weightless when it chose to be for all its enormous mass, armed with atomic guns that could blast a city to superheated vapor. Whoever controlled that ship could get to Galactic stars in a matter of weeks. Or could rule all Khazak if he chose.