Although not a definitive list (as with all technologies, things develop at a rapid speed) and including some experimental projects and projected speeds, we've taken a look at some of the fastest aircraft developed in the world. 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 of the fastest (as of writing - not necessarily the fastest) and countdown to number 1.
21. F-117 Nighthawk
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.
20. B-2 Spirit
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.
19. F-35 Lightning II
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 F-35 projects and as of 2014, 115 have been built.
18. Convair B-58 Hustler
Cost: $12.44m (per unit)
Top Speed: 1,300 mph
Time To Circumnavigate the Globe: 27 hours (approx)
The Convair B-58 Hustler was the first operational jet bomber capable of Mach 2 flight and was designed to be able to evade Soviet fighters at the time by being able to fly at supersonic speeds at high altitudes but the introduction of highly-accurate Soviet surface-to-air missiles forced the B-58 into a low-level-penetration role that severely limited its range and strategic value, and it was never employed to deliver conventional bombs despite being capable of carrying 5 nuclear weapons. Only operational between 1960 and 1970, the B-58 was notorious for its sonic boom, which was often heard by the public as it passed overhead in supersonic flight
17. Convair F-106
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
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
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
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
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 of service in 1998.
12. F-15 Eagle
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
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
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.
9. XB-70 Valkyrie
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'
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 as well.
7. Mikoyan-Gurevich MiG-25 Foxbat
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
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.
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.
By NASA - http://www.dfrc.nasa.gov/gallery/photo/X-15/HTML/E-5251.html, Public Domain, Link
6. Boeing X-51
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.
By US Air Force - http://www.af.mil/shared/media/photodb/photos/100520-F-9999B-111.jpg, Public Domain, Link
3. X43A Scramjet
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
By NASA - http://antwrp.gsfc.nasa.gov/apod/ap040329.html  Catalogue: http://www.dfrc.nasa.gov/Gallery/Photo/X-43A/HTML/ED99-45243-01.html Transferred from en.wikipedia to Commons by TheDJ using CommonsHelper., Public Domain, Link
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.
By David Neyland - http://www.ifpafletcherconference.com/2010/powerpoint/David_Neyland.ppt, Public Domain, Link
1. NASA Space Shuttle
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.