The first thing that you need to remember is that the things that people know in the world of Space:1889 are things that people would have thought possible in the Victorian era. The notions in Space:1889 conform to what people knew about the universe at the time. It is equally likely that ideas in Science Fiction today about future technologies and developments will be totally wrong as it was for the predictions of the Victorian Era.
Secondly, we must also remember that the world of Space:1889 is a fantasy world. It is a fantasy world where the dreams of the Victorian Era came true. As such, all that is important for believability is that it be self-consistent, which it largely is.
What is more important is that the GM and players understand the Atmosphere of the genre. They key to this game is adventure; a game of Space:1889 should be a wild ride of exploration, mystery, and action. In Space:1889, the player characters are heroes; rules apply to them differently than others, in a dramatic sense, because the characters are the focus of the story; as heroes, the characters are expected to accomplist things that ordinary folk dream of. That is the whole point of the adventure.
Some support for atmosphere and setting can be gained through novels and stories, particularily "Golden-Age" Science fiction.
I can say without shame that most of these modules are among the worst modules written for any game.
This is because most of the modules are so heavily scripted as to not even need the participation of the players. They generally start with a compelling story idea, but then they become so attached to their story concept that they take the process of storymaking away from the Adventurers, and put it in the hands of the NPC's, allowing the players only to participate in a few battles.
Scripting is a common problem among the modules of many game systems, but for some reason the modules of Space:1889 seem to be particularily bad in it. One of the worst examples is the module provided in the main rulebook, On Gossamer Wings, in which the players accompany Dr. Cyrus Grant on an expedition to the Moon. Virtually all party decisions are made by Dr. Grant, to the point that the players feel that they are being deliberately excluded and are helpless to affect the outcome.
One thing that is important to remember is that providing the characters with large amounts of detail is simply going to drag things out if the players do not have the opportunity to act on them. In On Gossamer Wings, the players are taken to the Moon by Doctor Grant in his ether flyer, and subsequently crashland on the Moon. During this process, Dr. Grant detects that the flyer has entered an atmosphere, and that the ether propeller is no longer working properly. He attempts to inflate the Hydrogen Gas Bag, but too late, and the ship narrowly crashlands on a ledge, rather than plunge to their doom.
Throughout this narrative, the players are merely observers, waiting for an opportunity to participate. By this point they are bound to resent the ations of the incompetent Dr. Grant, who got them stranded on the Moon in the first place. You'd probably have better luck just handing the players a summary of "the story so far", and start the adventure with the players already crashlanded on the moon.
However, if the party was involved in the operation of the ether flyer, then narrowly escaping death by plunging into the canyon can seem like an accomplishment. Not only would the players feel that they have been involved in the story, but they have even already had a taste of adventure!
Perhaps the simplest way to control the storyline is to allow the players to make die rolls. The GM can determine the necessity of the story and use this as a basis for deciding whether or not the roll is a success. As the Ether Flyer begins to plunge out of control, have the piloting player (someone other than Dr. Grant, unless Grant is being played by a player) make a piloting roll, and inform him that te roll may be difficult, as the controls are becoming sluggish.
After the player has made his roll, if the result was obviously a failure, tell the player:
"The Flyer drops with a lurch, and everyone goes flying as the bow of the flyer dips sharply. Descending ever faster, the flyer glances off the wall of the cavern with a sickening crunch. The controls are barely responding now, but up ahead you can see a ledge portruding from the wall of the cavern; hauling on the control stick you just manage to strike the ledge. You're thrown against the controls, and for a moment you black out, but you come to a split second later; the flyer is skidding along the ledge, and stops just short of the precipice..."
If the result was somewhat ambiguous, say:
"The controls feel like they're stuck in molasses, and the flyer swerves back and forth crazily. You know you've got to set the flyer down or else you're going to lose what control you have. Fortunately, you can see a ledge ahead of you, and you steer the flyer towards it. You set down with a crash, and a thump, and a screech; things fly off their shelves and people are knocked to the floor, as the flyer skids along the ledge. Finally the flyer hits the back wall of the ledge with a crunch sound. A quiet settles over the flyer, as everything shuts off or cools down. Well, it could have been a lot worse."
If the result was a clear success, say something like:
"The Flyer manouvers like a pig, but you manage to get her under control; you see a ledge ahead, and you think you might be able to make a landing, if you want."At this point, if the player wants to land, allow the character to make another roll to land the craft. If he does not, the flyer will continue to descend, and control of the flyer will become more difficult; the player may need to go through this process again... If the player's roll fails, or is ambiguous again, the flyer can still crash, like in the first examples. However, if he succeeds again, you can say:
"You level off the flyer, and steer towards the ledge; you realize that you don't have quite enough power to make it there; the flyer is still descending. You call back to Grant (or whichever crewmember is manning the Engineering section) telling him "I need more power or we'll miss the ledge!" Grant begins to work furiously at the ether propellor, rewiring and unplgging cables. He calls back "there! You've got all the power you'll need!" You throttle forward, and with a surge the flyer lifts a little and leaps forward towards the ledge. Yo're almost there, when a flash of blue light and a sharp crack! sound comes from the engineering section; Grant comes flying out and skidding along the floor, out cold, his face black and bloody. You set the flyer down just as the last bit of power drains from the propeller."
What you have thus achieved is allowing the player to have a part in the story, while guaranteeing that the necessary event, the crashlanding of the flyer, and the disabling of the ether propeller, has taken place. The other players may feel gratitude to the piloting player, whose skill has just saved all their lives.
Also remember that you can roll dice to yourself in order to make mandated events look like random events, and vice versa (by rolling dice in advance). No player is going to want to play an adventure that is controlled entirely by dice and random encounter tables (after all, they don't need a GM for that), but they're not going to want a module that has no surprises, either.
The promised Interlinear Rewrite of ON GOSSAMER WINGS is now here! Click Here to have a look!