Most modern cars have a latch release handle in the trunk, in case you get locked in against your will. My old (as in, a 2003 model) Ford Escort ZX2 even had a fuel shutoff switch in the trunk, presumably to keep a hijacker from making off in your car to do God only knows what to you at a secluded location. Well these are great security measures, being able to stop the vehicle and let yourself out. But let's suppose the carjacker becomes angry that the vehicle has stopped unexpectedly and gets out to try and fix it. He sees you open the trunk and before you climb out he either slams it shut again or decides to harm/kill you to ensure you stay put while he figures out how to get the car running again.
Now, let's assume you have a cellphone on you (who doesn't these days?) and you've managed to call the police. You need to stay alive long enough for them to get to you, but you're locked in the trunk and the bad guy has the keys. Well, my idea is for a security latch inside the trunk with which you can lock yourself in and the key won't unlock it so the bad guy can't get you out.
(Note: I recommend bulletproofing the trunk and keeping a compressed air bottle inside with a scuba mask in case he decides to sink the car in a lake or shoot you before ditching it)-- 21 Quest, Jun 27 2012 Remind us again, just where is the fuel tank on most passenger cars ... ?
So, your hijacker is now quite tetchy, has the keys to the fuel filler cap, and you're lying in a closed metal box on top of quite a large amount of volatile hydrocarbons. Let's assume also that the bad guy has a projectile weapon, or some other source of ignition such as a spark from the vehicle's battery.
Now, what's wrong with this picture ?-- 8th of 7, Jun 27 2012 I never said it addresses ALL scenarios... you just gotta have SOME luck on your side, I guess.-- 21 Quest, Jun 27 2012 Not at all like real life, then ?-- 8th of 7, Jun 27 2012 Maybe he didn't get the keys to the filler cap. I said this is for the justifiably paranoid, you should keep that key hidden anyway. The truly paranoid know better than to put all their keys on the same ring. I keep mine somewhere under the vehicle. And fuel tanks can be bulletproofed, I know I said I recommend bulletproofing.-- 21 Quest, Jun 27 2012 Do you have any recommendations for bulletproofing methods that won't destroy the vehicle's fuel economy or add thousands to the sticker price?
The least expensive method of armoring a vehicle is with steel. 1/4" of steel will stop any handgun round and all but the largest calibers (.40+) of rifle.
Let us assume a gas tank 32"W x 18"D x 8"H, roughly 20 gal. To armor that against small arms would add, including welds and heavy-duty mounts, about 160 lbs. That's just for the gas tank. Wrapping the entire trunk of a mid-sized sedan in 1/4" steel could easily add 500-600 lbs. to the weight of the vehicle, most of it behind the rear axle (that's a bad thing).
So let's explore alternatives. We could go with impregnated Kevlar, which is roughly 1/3 the weight of steel for equivalent protection, about five times as expensive, and will only stand up to a handful of shots before it crumbles. Then there's Chobham, a composite ceramic armor, which is roughly half the weight of steel, about fifty times the cost, and is restricted military technology...-- Alterother, Jun 27 2012 Russian-style ERA. Doesn't have to be very heavy at all.
Admittedly, the vehicle won't be able to do any miles *at all* after the dust settles, but then again, it won't consume any more fuel either.-- Custardguts, Jun 27 2012 And, as a bonus, our theoretical assailant likely won't be putting on much more mileage either.-- Alterother, Jun 27 2012 Nobody has addressed the fact that a justifiably paranoid person will have weapons in both the cab and trunk of their vehicle. At the least, armoring the trunk prevents them from firing out.
Arrow slot adaptations, anyone?-- normzone, Jun 27 2012 Baked by the DC Sniper...-- 21 Quest, Jun 28 2012 That guy was not a sniper, he was a muderer. I can't stand it when the press refer to anyone who shoots people with a scoped rifle as a sniper.
A sniper is a highly-trained soldier who uses superior stealth and tracking skills and a precision firearm to kill from afar. I'm very quiet in the woods and a good shot, but I don't go calling myself a sniper.
Rant over. Apologies.-- Alterother, Jun 28 2012 Yeah yeah, the point is he practically Baked the arrowslit idea.-- 21 Quest, Jun 28 2012 Actually, I think Archimedes may have beat him to it.-- Alterother, Jun 28 2012 Really? Archimedes designed a car with a hole in the trunk to be shot through?-- 21 Quest, Jun 28 2012 Yep, the Archimedes Benz.-- AusCan531, Jun 28 2012 random, halfbakery