unobtainium-based levitation engine
Hint : H G Wells.
But once you start invoking "unobtanium" the question arises as to how in blazes all the scientists looking for stuff like this missed it, but your protagonist found it on her own.
will allow her to start operating her own space agency! She's ready for her first test flight to make sure it's all working, but --
- Does she also have a method of navigating ?
- Breathing ?
- Eating ?
- Drinking ?
- Handling human waste products ?
- Dealing with life in zero-gee ?
- Keep the craft's temperature regulated ?
- Not being irradiated ?
- Not burning up on return ?
- Somehow converting levitation into a controllable thrust ?
- Build a craft which won't suffer failure - because everything can fail ?
- Or just throw the dice and hope it all works without problems ? (didn't work for anyone else).
- Has a backup plan ?
- How to communicate ? Needs a lot more than a radio.
- Who to communicate with ? Needs a lot of infrastructure back home.
- Power system for the craft ?
- Space suits ? These are really a lot more complex than people understand generally. They're almost mini-space ships on their own.
- Money - she'll need loads of this !
And these are but a fraction of the practical problems faced by any space craft, regardless of propulsion method.
Well, you see, she's not sure she wants the government muscling in on her little operation.
They're going to get awfully suspicious when she tries to use or build her own worldwide communications network, I can tell you that for nothing.
At best every intelligence agency on Earth (all of them) would be monitoring all the money flows and activity and resource movements. If they don't know what it's for they'd be even more suspicious - that's their jobs, and if they figure out what it's for they'll get very, very directly involved.
In the modern world hiding is impossible. The more you try to hide, the more suspicious you look. Encrypt your emails ? The equivalent of putting a neon sign up saying "I'm up to something very suspicious".
She should have some sort of cloaking device rolling out of the old noggin in a couple months or so, but by golly, she wants to go to space now.
A character like this would be dead on the first flight, because impulse driven and getting back from space alive are incompatible. The first astronauts were chosen not simply for bravery or skills, but because they had almost unbelievable levels of self discipline and willpower and particularly calm decision making skills in even the most extreme crisis. "Golly she wants to go into space now" types would be dead so fast from the huge number of things their impulse driven personality did not plan for, that the book would be a short story.
Assuming that the maneuverability of her modified family car
A modified family car would be about as likely to survive the trip as the idiot who got into it.
And just how well will Mary Sue react to being trapped in a family car seat (in a space suit) with no place to go during the trip. Astronauts are also chosen for this kind of mental capability - not at all trivial.
The idea makes H G Well's fantasy trip sound rational and well planned. Modifying the family car is something Disney would be embarrassed by (not that this would prevent them selling it).
is limited only by the squishiness of the pilot and the detectable power signature of the engine itself slightly less than the average toaster that you forgot to plug in, what kinds of altitudes can she levitate to without drawing the government's attention ?
Levitating and the government are not the problem. Staying alive is.
In principle, however, modern radar would not detect her at this size. It's quite hard to detect an object without a transponder, particularly a small one.
How fast can she set the throttle ?
How many gees can Mary Sue and the "modified family car" (!) withstand. Not many. For how long will this acceleration be maintained ?
Has Mary Sue heard of the sound barrier ? Aerodynamic forces ? The way high speed supersonic aircraft surfaces heat up due to friction with the air (even at high altitude) ?
Mary Sue - first woman to levitate herself into the Darwin Awards.
How many test flights should she consider safe (either from detection or to consider the engine a success) ?
How many car trips would you consider "safe" ? Because it's always the next one that the accident occurs on. There's no safe, there's only calculated risk. How much risk does she consider acceptable ? If I told Mary Sue there was a 10% chance of dying would she be OK ? That's what a well designed, carefully tested, full fledged space program might manage.
In a "modified family car" (seriously does that sound insane as you read it ?) the odds of a successful flight are, IMO, as close to zero as makes no odds. The materials are simply inadequate to the task, and the base structure is not suitable for aerodynamic loading. Break up during first flight, I'd say.
But "Golly, she wants to go to space now.".
Is there any particular places she might go to make it easier or harder to avoid detection ?
She should go to school, maybe try for a university. Maybe the library if that's not possible. She could desperately do with reading every book on physics and engineering she can.
No place is not covered by satellites. Space is monitored in case, e.g. someone launches nukes at someone else (about the size of a family car you say, she'll probably trigger WW3 ).
What about when she's ready to call it all good and make the leap to orbit ? Is there any way to do this covertly from Anytown, USA ?
Only in X-Men comics. In the real world when you land the entire world will be awaiting your return. And they won't be happy. In the USA the different agencies would have about a million arguments between themselves about who gets to jail you first. You'd never get to see a lawyer.
A perspective on how different techniques might appear to the government if they do get noticed but not red flagged would also be welcome.
Unauthorized use of airspace leaps to mind.
Spying is an option.
Possibly unsafe use of a motor vehicle or illegal parking if she's not real careful.
No pilots license ? No flight plan ?
Uncertified aircraft ?
Possible anti-terrorism laws ?
Surveillance of military installations (did she look down ?) ?
Illegal entry into a country ? (careful where you land, Mary Sue).
Triggering WW3 ?
Failure to file taxes ? (you did say she was trying to hide)
And what if the Governemnts already have unobtanium hidden in their secret labs ? Black Helicopter time, methinks.
But the thing is, Governments would have one view that involves Mary Sue's permanent placement in a gilded cage in a really secure military facility while she "helps them".
Even in the extremely unlikely even Mary Sue survived a single test flight, let alone a real trip, Mary Sue would disappear off the face of the Earth.