Aircraft Speed Record at Sea Level
Official record for manned flight -
The Lockheed SR-71 Blackbird holds the official Air Speed Record for a manned airbreathing jet aircraft with a speed of 3,529.56 km/h (2,194 mph). It was capable of taking off and landing unassisted on conventional runways. The record was set on 28 July 1976 by Eldon W. Joersz near Beale Air Force Base, California, USA.[8]
For a period of time, during and immediately following World War II, the unpublicised and unofficial speed record of 1004.5 km/h (623.8 mph) set by the Messerschmitt Me 163AV4(the third prototype) rocket aircraft, on October 2, 1941 was actually the fastest velocity any aircraft had been measured as traveling to that time. That figure, set during wartime when no records were being ratified, was achieved by the Me 163A V4 at altitude rather than sea-level as it had been towed by a Bf 110 to set the record. Many record attempts were stated as being “set” after World War II by such aircraft as the Gloster Meteor, which exceeded the 755 km/h (469 mph) velocity record of the pre-war holder (the Messerschmitt Me 209 V1 piston engined aircraft) but the first to actually exceed the Me 163 A V4 claim was the Douglas Skystreak on August 20, 1947.
The fastest manned atmospheric vehicle of all time was the Apollo command module as it returned from the moon, reaching speeds of around Mach 30. Although it used the air largely as a brake, it did also achieve a lift to drag ratio of around 0.368[9] which was used to control the flight trajectory. However this is probably very different from most people’s idea of an ‘aircraft’, and a L/D ratio of 1 or above is arguably the borderline of what may be considered flying.
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Official record for unmanned flight -
Faster Than a Speeding Bullet: Guinness Recognizes NASA Scramjet
NASA set the record in November during the third and final flight of the experimental X-43A scramjet (supersonic-combustion ramjet) project. The X-43A demonstrated an advanced form of air-breathing jet engine could power an aircraft nearly 10 times the speed of sound. Data from the unpiloted, 12-foot-long research vehicle show its revolutionary engine worked successfully at Mach 9.6 (approximately 7,000 mph), as it flew over the Pacific Ocean west of California.
The flight was the culmination of NASA’s Hyper-X Program. Hyper-X, a seven-year, approximately $230 million ground and flight test program, explored alternatives to rocket power for space access vehicles.
This is the second world speed record earned by the Hyper-X Program. The first followed a Mach 6.8 (approximately 5,000 mph) flight in March 2004. Both records will be featured in the 2006 edition of the Guinness World Records book published in September 2005. The fastest air-breathing, manned vehicle, the SR-71, achieved slightly more than Mach 3.2. The X-43A more than tripled the top speed of the jet-powered SR-71.
NASA is interested in supersonic combustion scramjet technology, because the engines get their oxygen from the atmosphere. That allows for more airplane-like operations for increased affordability, flexibility and safety in ultra-high-speed flights and for the first stage to Earth orbit. Once a scramjet-powered vehicle is accelerated to approximately Mach 4 by a conventional jet engine or booster rocket, it can fly at hypersonic speeds, possibly as fast as Mach 15, without carrying heavy oxidizer, as rockets must.
A ramjet operates by subsonic combustion of fuel in a stream of air compressed by the forward speed of the aircraft. In a regular jet engine, fan blades compress the air. In a scramjet, the airflow through the whole engine remains supersonic.
The Guinness World Record certificate:
“On 16 November, 2004, NASA’s unmanned Hyper-X (X-43A) aircraft reached Mach 9.6. The X-43A was boosted to an altitude of 33,223 meters (109,000 feet) by a Pegasus rocket launched from beneath a B52-B jet aircraft. The revolutionary ’scramjet’ aircraft then burned its engine for around 10 seconds during its flight over the Pacific Ocean.”
Related flight records:
The previous record for an air-breathing vehicle, but not an airplane, was held by a ramjet-powered missile, which achieved slightly more than Mach 5. The highest speed attained by a rocket-powered airplane, NASA’s X-15, was Mach 6.7.
The Hyper-X program was conducted by NASA’s Aeronautics Research Mission Directorate with the agency’s Langley Research Center, Hampton, Va. Langley was lead NASA center with responsibility for hypersonic technology development. The NASA Dryden Flight Research Center, Edwards, Calif., is responsible for flight research and testing.