Why making an airplane engine is so expensive ???

To answer this first we have to know that the aircraft engines run for hours at high temperatures, and they must resist it without breaking.

That's why your usually use titanium to build the engines. But the titanic is expensive. The plane in general is expensive. Very few people save that the price of the airplanes is quite similar to the one of the rocket. But the rocket are only used once, and the planes are being used. That's why it's not worth a plane ticket than a plane ticket.

For all this, and because the engine has thousands of sensors, aircraft engines are so expensive and difficult to build.

http://www.bbc.com/autos/story/20170214-how-jet-engines-are-made

The last trip of X-15

http://www.bbc.com/future/story/20160927-the-bomber-that-paved-the-way-for-the-moon-missions

The X-15 was the first plane to arrive to the space.  In 1963, Joe Walker an experimental pilot of the U.S. air Forces, managed to cross the border of the space, 100 km. But in the moment he doesn’t was an spaceman, only one more flight. But in 2005 the NASA make him an astronaut.

In 1968, the first space plane was retired. After 199 flights and 12 pilots the plane was abandoned in a huge aircraft museum.

But now a team of experts is cleaning and restoring the two planes that are still. In a few days they will take the planes, on their last trip, to a new museum where they will be able to see during the following 100 years.

The risk of the IA

In the last times, the technologies of artificial intelligence has swelled exponential rate, and the best scientists of the world have a question: is really secure the AI?

But first, what is the AI?

The IA have machines that can do task therequire intelligence. The essential difference between a normal machine and an AI is that machines obey your orders, but the IA has the capacity to understand what is doing and self-programming to get it.

Returned to the principal term, the Ai are not dangerous if we can control it. But we must go with care because if we use badly it can be very dangerous.