Since the arrival of the first jet engine in the mid-20th Century, combat aircraft have made great strides.
Many of the most powerful military planes currently in service have been around for many decades.
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Every navy and air force feels the need to be fast. It's a fact. Speed is crucial when trying to scramble the defending aircraft.
Since the invention of the first jet engine, in the middle of the 20th century, aircraft designers have made great strides. Today, an aircraft that cannot cruise at supersonic speeds may as well be a propeller-powered diesel plane.
Human engineering was slow and tedious to reach the point that fighter aircraft now have a radar cross section like a bumblebee. These are the fastest examples currently in use.
1. Boeing X-37
In June 2009, the Vandenberg Air Force Base in California hosted the X-37B Orbital Test Vehicle. US Air Force
The Boeing X-37 space drone is unmanned and operated by the US Air Force. NASA launched it into space. Its purpose is to test space technology and return to Earth.
The X-37 descends at an average speed 16 times faster than sound, but it has returned as fast as Mach 25, on its way back up.
An MiG-25. Wikimedia Commons
The Soviet-built MiG-25 is still the fastest fighter in service. This fighter was designed by Mikoyan to be an interceptor aircraft.
The Foxbat's cruising speed is Mach 2.8, while the top speed is Mach 3.2. This is a great technology for an aircraft that was first launched in 1964.
3. F-15E Strike Eagle
An F-15 flying over Afghanistan. The US Air Force
The F-15 has been in flight for over 30 years. It is expected to continue flying. It is a good design. Another aircraft was originally designed to capture and destroy enemies.
The F-15 can fly at speeds of 3,017 mph, then slow down, hit ground targets and disappear.
4. MiG-31 Foxhound
MiG-31. Russian Defense Ministry
The Russians called upon the MiG-21 hypersonic missiles and Kinzhal hypersonic weapons when they needed to hunt down the SR-71 Blackbird.
It doesn't handle quite as well as the MiG-25. It is slower than its predecessor, the MiG-25, at 2,993 mph.
5. Sukhoi Su-27
Russian Su-27. RAF
The Soviet Union's answer for the F-15 is the Su-27, a heavy fighter designed to take on the role of the F-15.
It was first flown in 1977. Today, a few countries still use it for its 2,496 mph top speed. Four Su-27 planes are used by the United States to train pilots.