Ok way back just after WWII from around 1946 through about 1956, tether cars and also rail cars were all the rage. Everyone in the UK and the USA and Europe were all into tether cars (rail cars tended to be mostly a UK thing though). It is similar to control line airplanes in that a line is attached to the car and it runs in a circle around a track. Today the vintage tether cars can all command hefty prices when sold. But many people make them themselves and machine all the parts as needed. They still hold international competitions will all sorts of classes based on engine displacement, fuel, etc. Tether boats were also quite popular back then too. But at present tether boats are still run un the UK at a few special ponds made for that purpose. Rail cars are run on a special track and they have rails that are used to keep the cars in their lane, the cars have special wheels that mate with the rails on the track. I don't think anyone has a rail track setup anywhere anymore though.
ref http://en.wikipedia.org/wiki/Tether_car
Cox used to sell many different types of tether cars for kids to use. Testors did too as well as OK, Comet, Gilbert and some others as well. You might have used one of these little .049 engine powered tether cars as a kid too.

Free flight planes were being flown way back before 1900. They started out just tossing gliders off a hill, then later rubber band powered versions came about as well as compressed air or compressed gas engine powered planes were used. Compressed air engine powered planes actually had a competitive advantage up into the 1930's for free flight compeititons. These are basically airplanes that are flown without a radio control system or control lines. The design of the free flight plane is such that it is self flying without a radio control system. They may use timers and dethermalizers on them to help limit the flywaways. ref http://en.wikipedia.org/wiki/Free_fl...model_aircraft)

FPV means first person video or visual. They use a radio controlled airplane with a video camera mounted on it and a way to send the signal back to the user. The user either uses a video monitor or wears special video goggles and can control the airplane just as though he is actually in the plane flying it. These could be quite simple as a radio control airplane using a camera and the user just flies it around recording stuff with the camera. Later they added FPV features so you can feel more like you are inside flying the plane yourself. Radio control systems can be obtained that extend the range beyond the 1 kilometer range that current RC systems can provide. They also have GPS systems and programming available to allow the plane to fly a preprogrammed course and or return automatically in case the radio signal is lost. The public has started seeing these small FPV planes as being drones too.

The commerical or military robotic planes or drones tend to be very expensive and able to fly for long distances and duration and may be armed or unarmed. They can be a FPV type of plane just like the hobbyist types too. The hobbyists tend to use the FPV airplanes whereas the other business and military and scientific groups are using the drones mostly. There can be problems with various governments passing laws and defining drones as anything with a radio control system that can fly. So the AMA has been working hard to help educate the lawmakers about it.

Some big business interests have a vested interest to have FPV and drone planes banned or prohibited as they don't want anyone flying them and recording and taking pictures of their illegal activites. There have been some cases of a guy trying out his new FPV plane and taking photos and videos of a large company deliberately polluting a river or creek, or a company staging illegal hunts of protected animals, and so on. These have made the news in the past. Of course other people don't want them flying around and taking pics of their illegal growing plots either. The public is afraid that someone might use them to take pics of them in a compromising situation too. Peeping toms is another problem and paparazzi another problem with them too.


Flying at night is a popular RC flying club pastime too. We did it many years ago Just using Cylume glow sticks taped or rubber banded onto a RC plane. Nowadays many folks use LED light strips on their planes.


You can see some tether cars and boats in this website that use the model airplane engine with a propeller to propell the car in a circle. They are likely the easiest to build in comparison with the more sophisticated tether cars and boats. http://www.mh-aerotools.de/airfoils/cox_models.htm


You can see the tether cars in use here:

http://blog.hemmings.com/index.php/2...-in-the-1940s/