Inspired by the short story "The Road Not Taken" by Harry Turtledove I've tried to picture the universe described. For those unfamiliar with its setting:
In the world of "The Road Not Taken" gravitational manipulation and FTL drive is fairly easy to discover and construct - humanity has just somehow not stumbled upon this technology yet. It is easy enough so that civilisations with technology equivalent to ours age of discovery era are capable of space travel, colonisation and most importantly - conquest. This technology can be effectively applied only to transportation.
Construction of a spaceship using technology available sometime between 15th and 19th century (the earlier, the better!) is quite a task. Luckly, drive is not a concern! Resembling rather a big box like object, with pilot attached to it, Handwavium Drive can move with arbitrary force in any direction and speed, including FTL outside of stars gravitational wells - we've got the technology! Addtionaly, thanks to drive's gravitional manipulation effect we can negate effects of high accelerations force overloads. It has rendered journeys between neighbouring stars in time and logistical effort comparable to our 17th century voyages from Europe to India.
As we all know space travel is always accompanied by multiple issues including, but not limiting to:
- Cosmic radiation. We can lift easily any mass, hence radiation shield has nearly no limit to its mass - as long as ship will not collapse under its own mass when left idle on planet. What materials in industrial qunatities available in that period of time could be used for this purpouse? Can the shield be located only in ships prov, as most of the journey will be at FTL velocities?
- Air leakage. If I recall correctly, even modern spaceships are not perfectly hermetic - air atoms are constantly leaking through the hull. Using state of art engineering of colonization era would it be possible to keep the crew from suffocating during months long journey?
- Pilot visibility. Without modern radars how could the pilot see what is happening outside of his ship? Obvious guess is kind of a windshield, but I have hard time imaging that such windshield would be able to withstand pressure differences found between spacecraft and the void surrounding it.
- Space pirates! Last but definitely not least, there can't be colonization era spaceships without proper pirates! Could space pirate ships with preindustrial weaponry and no automation pose any threat to other ships if both vessels could travel at relativistic velocities?
Proposed solutions should rely on the drive technology as little as possible, except for transportation and logistics.