By Computer.
When they don't work!
Of course they work - didn't you ever see an airplane flying?
Airplanes.
No. Gliders, jets and rocket-propelled aircraft do not have propellers.
RTF airplanes also known as "Ready to Fly Airplanes" are airplanes that are already put together and require only a little bit of assembling. I obtained this information from this website: http://www.mostrealisticai.com/rc-airplane-kits.html
As I work on Boeing 747's, I can confirm they do have Windscreen Wipers.
The technology on airplanes is not old, the concept of some things might be and it is simply because they work and they are reliable.
Of course you could use fleet software to keep maintenance records for airplanes. You can get information on aircraft maintenance software at http://www.capterra.com/aviation-maintenance-software
Fixed wing aircraft work by using a kind of propeller or engine to pull the aircraft forward and the wings produce lift.
Old Airplanes and new are similar because they work under the same principles. Creating enough lift to become airbourne. To do so a plane needs to be light enough with enough thrust and enough surface area of the wings to create the lift
All gliders are airplanes, but not all airplanes are gliders.