Why don't they have Nuclear powered cars or airplanes

Question

Why don't they have Nuclear powered cars or airplanes

Answer 1

There are a lot of stupid laws related to nuclear technology put in place due to exaggerated fears of radiation and general irrationality which would make it legally impossible to actually build one regardless of whether you can do it technically.

With nuclear powered cars the shielding required is likely to be too heavy to be able to fit on a car (although a radioisotopic power source might be workable).

Nuclear powered aircraft are quite possible though with the US project to build one failing due to mismanagement (and not the impossibility of the project).  The one issue with nuclear powered aircraft as well as spacecraft is that you can't fully shield the whole reactor, just the part facing the crew which leads to some operational limitations (i.e. can't fly low over populated areas) but they are very much possible although the project ended before they had flight usable hardware.

Answer 2

If people do not like nuclear power plants near where they live, they will not like them on roads or (worse) flying overhead.  

There are lots of regulations (NRC) on "special nuclear materials" and these would *add* to the regulations on normal cars or airlines.  

Answer 3

The shielding would weigh too much. What happens if U have a wreck.

Answer 4

They could do it but letting people own their own reactor or have enough plutonium for a nuclear battery is far too risky.  It would not take many cars worth of material to make a bomb.

Answer 5

Because they scare people, mostly.  I think there are a number of ways to use the concentrated heat from a nuclear-waste reactor; some make electric power and some boil water to make steam.  It wouldn't be such a bad idea.  There were also plans for a nuclear powered railroad locomotive.  

Answer 6

As the others have said shielding is one issue the other is what do you do about shutting it down.  It would be about like a steam engine it would require time to fire it up and shut it down.  Then back on the shielding issue is enclosing them in a strong enough container to prevent leakage of radioactive material in the event of a crash.  I guess it would reduce onlooker delay if there were accidents.

There are small nuclear engines using the sterling cycle and used on space craft.   But in a car or plane you'd have to find a way to get rid of the heat generated when you weren't using them.  Maybe hook it up to a generator at your house.

Answer 7

The equipment required to make nuclear power is huge, heavy, and expensive.  None of that makes it practical to put in a car or a plane.

Do you really want to make it that easy to buy nuclear materials?  Terrorists would love that.

Answer 8

we can`t make small enough nuclear reactors to run cars. It would not be a good idea to allow everyone to have a source of radiation parked on their driveway , terrorists would steal the cars to make bombs.With aircraft the reactors would be to heavy to get off the ground and imagine the spread of radiation if a flying reactor crashed.A nuclear spacecraft was destroyed before it re-entered the atmosphere recently as there was a worry that radiation would be spread over Australia.