In nautical miles per hour for most purposes but in Mach number for supersonic flight.
It means the sum of the measured/calculated speeds divided by the number of speeds that were measured/calculated.
No, an aircraft can travel at speeds of 500 MPH and faster, so to stop an aircraft would result in it having to land.
flaps create lift when the aircraft has low speeds http://science.howstuffworks.com/airplane13.htm
the x-43 is the fastest unmanned aircraft reaching speeds up to 7,500 mph
A huge range of speeds from light civilian aircraft at about 100+mph, passenger jets around 500, right up to fighter jets at over 1400 mph
It is supposedly the SR-71 blackbird built by Lockheed Martin and was capable of speeds of mach 3.5 and over. Although its true top speed is classified, from the speeds we do know of, it is the fastest aircraft... that was manned. Unmanned aircraft are a different story.
Wind.
If both speeds are measured in the same medium, whether it be vacuum, water, or jello, then they are equal.
Aircraft towing speeds depend on the operating airline or airforce, but are usually around 4 - 5 mph.
They are called Supersonic aircraft. Some aircraft can only do that. Some planes have reached even Hypersonic speeds.
Aircraft productivity is the measure of the craft's productivity. It's measured by dividing aircraft block hours by the days allocated to service on air.
The properties of air flow at supersonic speeds is different than for subsonic speeds. So the design of the shape of the airplane and the inlets for the engines have to be different in order for it to fly at supersonic speeds.