In 2013, Lockheed Martin announced development of the successor to the SR-71 Blackbird spy plane.

The SR-71 was capable of reaching speeds over three times the speed of sound, and the SR-72 is intended to have even more impressive specs. Following is a transcript of the video.

The SR-72 is the successor to the SR-71 Blackbird spy plane, which was the fastest plane to ever exist.

Built by Lockheed Martin in the 1960s, the SR-71 could reach speeds exceeding Mach 3 (above 2,200 mph). That's over 3 times faster than the speed of sound. The recon jets went out of service in 1998.

Development of the SR-72 was announced in 2013.

It will be headed by "Skunk Works," Lockheed's advanced development program. Lockheed calls the SR-72 a "game changer." The jet will be an unmanned hypersonic aircraft.

Lockheed claims it will reach speeds topping Mach 6 — over 4,500 mph — and they also want the jet to do more than just recon missions, including the ability to strike targets.

Experts say the jet could reach anywhere in the world within an hour.

Rumors of sightings have flooded the internet. Recently, an unmanned aircraft was seen at a Skunk Works facility. Reports say it could have been an early test for the SR-72. Lockheed confirmed plans to fly a research vehicle in the early 2020s.

If all goes well, it may not be long before the fastest plane ever hits the skies.