SR-71 Blackbird, The World Extremely Fastest Jet

Video credit: Out Of Your Mind

The Lockheed SR-71 spy plane was and still is the fastest plane on the planet. This aircraft was developed in secret in the late 1950s to cruise to 80,000 feet above the earth, near the edge of space, and out fly any missile that was launched at it. 

The SR-71 was designed for flight at over Mach 3 with a flight crew of two in tandem cockpits, with the pilot in the forward cockpit and the reconnaissance systems officer operating the surveillance systems and equipment from the rear cockpit, and directing navigation on the mission flight path. The SR-71 was designed to minimize its radar cross-section, an early attempt at stealth design. Finished aircraft were painted a dark blue, almost black, to increase the emission of internal heat and to act as camouflage against the night sky. The dark color led to the aircraft's nickname "Blackbird".

The Blackbird, which first took flight in 1964, could enter hostile airspace, take photographs from those extreme heights like a tourist on vacation and still be on its way before an enemy had a chance to even take a shot at it. While it could cross continents in just a few hours, the aircraft also flew so high that pilots navigating by sight couldn’t rely on ground features such as roads and instead needed to look at the mountains, rivers, and major coastlines to get their bearings.

The secret to the aircraft’s speed and agility is largely in its unique engine inlets--a duct where air in brought into the engine. To handle the dramatic changes in speed and pressure, air is slowed to subsonic speeds before entering the SR-71’s jet engines.

The exhaust from the SR-71’s jet engines creates a diamond pattern. That’s due to the extra thrust provided by its supersonic afterburner. This creates successive shock waves that show up as the diamond pattern. The SR-71 engines fly continuously in afterburner, except when refueling.

Flying more than three times the speed of sound means that the aircraft has to withstand heat. The SR-71 generates 316° C temperatures on its external surfaces, which are enough to melt conventional aluminum airframes.

That's why the SR-71's external skin is made of titanium alloy that shield an internal aluminum airframe. The tires, which retract into the wings during flight, also have to keep from melting. To create the tires, latex was mixed with aluminum, and filled with nitrogen. The tire pressure on the SR-71 was 415 psi--10 times more than an average set of car tires.

With its ability to reach high speeds and high altitudes, the SR-71 was used to gather intelligence for the U.S. military during the Cold War. The aircraft could survey up to 160,934 square kilometers of territory in just one hour. Its stealthy design also reduced its chances of being detected on radar.