Usually developed as military projects, the advancement of technology has seen some incredibly rapid vehicles flying through our skies. Here we look at the 20 fastest and countdown to number 1.

20. F-117 Nighthawk

Cost: $111,200,000

Top Speed: 617mph

Time To Circumnavigate the Globe: 40.36 hours

A secretive project that saw a twin engine, single seater plane developed for the US military. Operational from 1983, it saw action in the Gulf War 1991 and during the Yugoslavia conflict 1999 where one was shot down making it the only one ever lost in combat. Retired in April 2008.

19. B-2 Spirit

Cost: $737,000,000

Top Speed: 630 mph

Time To Circumnavigate the Globe: 39.53 hours

Commonly known as the stealth bomber, it was designed so as to not be seen on radar (although radar technology has since developed). Used in Kosovo 1999, it also saw action in Afghanistan and Iraq.

18. F-35 Lightning II

Cost: $106,000,000

Top Speed: 1,200mph

Time To Circumnavigate the Globe: 20.75 hours

Designed to perform ground attacks and aerial reconnaissance it is a descendant of the F-25 and the X-35 projects and as of 2014, 115 have been built.

17. Convair F-106

Cost: $25,100,000

Top Speed: 1,520mph

Time To Circumnavigate the Globe: 16.4 hours

The primary all-weather interceptor aircraft of the United States Air Force from the 1960s through the 1980s, it was gradually phased out over the 80s as they were converted to unmanned drones that lasted into the 90s.

16. Sukhoi PAK FA T-50

Cost: $50,000,000

Top Speed: 1,526mph

Time To Circumnavigate the Globe: 16.38 hours

The first operational plane in Russian service to use stealth technology, this plane will be operational sometime this year or next.

15. Sukhoi Su-27

Cost: $27,000,000

Top Speed: 1,550mph

Time To Circumnavigate the Globe: 16.03 hours

A Soviet plane first in use in 1977, it was designed to out-do several American planes in service at the time. So renowned for reliability several are still in use in Russia, Belarus and Ukraine.

14. F-4 Phantom

Cost: $17,883,000

Top Speed: 1,607mph

Time To Circumnavigate the Globe: 15.6 hours

The superior bomber during the Vietnam war, only outdone by the Vought F8 Crusader.

13. F-111 Aardvark

Cost: $25,000,000

Top Speed: 1,650mph

Time To Circumnavigate the Globe:15.06 hours

Entering service in 1967, this plane can go twice the speed of sound and was widely used during the Vietnam war. Largely phased out from service in 1998.

12. F-15 Eagle

Cost: $27,900,000

Top Speed: 1,650

Time To Circumnavigate the Globe: 15.06 hours

Designed in 1967, this plane is thought to be one of the most successful military aircraft of all time and is expected to stay in service until 2025 in the US airforce with Japan, Saudi Arabia and Israel also using them.

11. Mikoyan Ye-152

Cost: Unknown

Top Speed: 1,666mph

Time To Circumnavigate the Globe: 15 hours

Developed by the Soviet Union, this is the fastest single jet engine they ever made.

10. Mikoyan MiG-31 Foxhound

Cost: $57,000,000

Top Speed: 1,860mph

Time To Circumnavigate the Globe: 13.36 hours

Introduced to the Soviet Air Defense Forces in 1982, this plane is still in service in Russia and Kazakhstan.

Retired in April 2008.

9. XB-70 Valkyrie

Cost: $750,000,000

Top Speed: 2,000mph

Time To Circumnavigate the Globe: 12.43 hours

A six engine plane built for a hypothetical nuclear strike, this was just a prototype built in the 1950s and flown in 1964 and 1969, it was never used in service.

8. Bell X-2 'Starbuster'

Cost: $64,000,000

Top Speed: 2,094mph

Time To Circumnavigate the Globe: 11.87 hours

Built as a research plane to investigate aerodynamics and supersonic flight. On its final flight, when above Mach 3, the pilot tried to turn the plane and lost control dooming himself and the plane and thus ending the program aswell.

7. Mikoyan-Gurevich MiG-25 Foxbat

Cost: $18,000,000

Top Speed: 2,190mph

Time To Circumnavigate the Globe: 11.35 hours

One of the fastest ever planes to enter operational service, it is still in use today in Russia, Algeria and Syria despite first being employed in 1970.

6. SR-71 Blackbird

Cost: $43,000,000

Top Speed: 2,500mph

Time To Circumnavigate the Globe: 9.9 hours

 A highly secretive project, this plane was in operation from 1964 until 1998 and was used during the Cold War period for highly successful reconnaissance.

5. X-15

Cost: $1,500,000,000

Top Speed: 4,520mph

Time To Circumnavigate the Globe: 7.4 hours

An experimental plane jointly operated by NASA and the US airforce, this vehicle currently holds the world record for fastest manned aircraft, going at 6.72 times faster than the speed of sound.

4. Boeing X-51

Cost: $7,700,000

Top Speed: 3,400mph

Time To Circumnavigate the Globe: 5.5 hours

A pilotless plane that is still under development, it is designed to be a super fast strike weapon with the intention of being operational in 2020.

3. X43A Scramjet

Cost: Unknown

Top Speed: 7,500mph

Time To Circumnavigate the Globe: 3.34 hours

Developed after the second world war, recent leaps in technology means that the project has finally been able to develop hypersonic capabilities. Still a work in progress

2. X-41

Cost: Unknown

Top Speed:13,000mph

Time To Circumnavigate the Globe: 1.9 hours

A project under development by DARPA and the US military to launch missile strikes anywhere in the world in under an hour.

1. NASA Space Shuttle

Cost: $450,000,000

Top Speed: 17,500mph

Time To Circumnavigate the Globe: 1.4 hours

Actually designed for space travel, if this flew within the Earth's atmosphere it would be the fastest aircraft known to man.Retired in April 2008.

Source: http://lifehacklane.com/1205/the-fastest-planes-in-the-world/

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