Speed of the Fastest Airplane
Bibliographic Entry  Result (w/surrounding text) 
Standardized Result 

Boyne, Walter. World Book Encyclopedia. New York: World Book, 1996: 208.  "… a rocket plane the fastest kind of airplane … a speed of 4,520 mph"  2020 m/s 
Lockheed SR71A. Air Force Armament Museum. Eglin Air Force Base, Florida.  "… an SR71 set two world records for its class: an absolute speed record of 2,193.167 miles per hour"  980 m/s 
Guinness Book of World Records 1968. New York: Bantam, 1968: 249.  "… the official air speed recordis 2,070.102 mph by Col. Robert L. Stephens"  925 m/s 
Guinness Book of World Records 1989. New York: Bantam, 1989: 204.  "The official air speed record is 2,193.167 mph by Capt. Eldon W. Joersz in a Lockheed SR71A"  980 m/s 
In the search for the speed of the fastest airplane in air speed, the first problem was to find the difference between regular speed and air speed. Air speed is defined as the speed of an airplane with relation to the air, as compared to regular speed, which is the speed relative to the earth.
In 1968, according to the Guinness Book of World Records, a record airspeed of 2,070.102 mph (925 m/s) was achieved by a Lockheed YF12A. The 1989 Guinness Book states that a record airspeed of 2,193.167 mph (980 m/s) was achieved by a Lockheed SR71A, which is a newer version of the YF12A. The online source from the AFAM web page agrees with this number to the thousandths place, and it was recorded 7 years later. As it says, this plane has held this record speed for 24 years. The 1996 World Book Encyclopedia has a different answer of 4,520 mph (2020 m/s). This difference in opinion can be explained by the fact that this record speed was performed by a rocket plane, which differs from the type of plane mentioned in the other sources.
The source from 1968 differs from the more recent data because since 1968, engines and designs of planes have been advanced due to technological advances so that planes can fly faster. Of course there are other faster speeds. The US Space Shuttle flew at a record 16,000 mph (7153 m/s). These machines aren't planes and they achieve these high speeds only during reentry.
Aviva Laurenti  1998
Bibliographic Entry  Result (w/surrounding text) 
Standardized Result 


Blackbird Records. SR71 Online: An Online Aircraft Museum.  "27/28 July 1976 Crew: Capt. Eldon W. Joersz and Maj. George T. Morgan Speed Over a Straight Course: 2,193.167 mph" 
980.4334 m/s  
"27/28 July 1976 Crew: Maj. Adolphus H. Bledsoe, Jr. and Maj. John T. Fuller Speed Over a Closed Circuit: 2,092.294 mph" 
935.3391 m/s  
"6 March 1990 Crew: Lt. Col. Ed Yeilding and Lt. Col. Joseph T. Vida Speed Over a Recognized Course  St. Louis to Cincinnati (311.44 mi) Time: 8 minutes 31.97 seconds Average Speed: 2,189.94 mph" 
978.991 m/s  
"6 March 1990 Crew: Lt. Col. Ed Yeilding and Lt. Col. Joseph T. Vida Speed Over a Recognized Course  Los Angeles to Washington, DC (1,998 MI) Time: 1 hour 4 minutes 19.89 seconds Average Speed: 2,144.83 mph [1863 mph]" 
958.824 m/s [833.0 m/s] 

"6 March 1990 Crew: Lt. Col. Ed Yeilding and Lt. Col. Joseph T. Vida Speed Over a Recognized Course  Los Angeles to East Coast (Coast to Coast, 2,086 MI) Time: 1 hour 7 minutes 53.69 seconds Average Speed: 2,124.5 mph [1843.44 mph]" 
949 74 m/s [824.1 m/s] 

"1 September 1974 Crew: Maj. James V. Sullivan and Maj Noel F. Widdifield Speed Over a Recognized Course  New York to London Time: 1 hour 54 minutes 56.4 seconds Average Speed: 1,806.964 mph" 
807.7852 m/s  
"13 September 1974 Crew: Capt. Harold B. Adams and Capt. William C. Machorek Speed Over a Recognized Course  London to Los Angeles (5,645 MI) Time: 3 hours 47 minutes 35.8 seconds Average Speed: 1,435.587 mph [1488 mph]" 
641.765 m/s [665.3 m/s] 

New York to London SR71 Speed Run, Leyland R. Haynes  "On September 1, 1974 Major James V. Sullivan, 37 (pilot) and Noel F. Widdifield, 33 (reconnaissance systems officer) (photo inset), flashed across the starting line (radar gates in New York) at approximately 80,000 feet and speed in excess of 2,000 miles per hour. Exactly 1 hour 54 minutes and 56.4 seconds later, they had set a new world speed record from New York to London England. The average speed was 1,807 statute mph over the 3,461 statute mile course, slowing to refuel one time from a specially modified KC135 refueling tanker."  807.6 m/s  
"Another historic speed record was set on the return trip to the United States. Capt Harold B. Adams, 31 (pilot), and Major William Machorek, 32 (reconnaissance systems operator), set a speed record from London to Los Angeles. They returned the Blackbird 5,447 statute miles in 3 hours 47 minutes and 39 seconds for an average speed of 1,435 miles per hour [1436 mph]."  641.8 m/s [641.8 m/s] 

World Record Speed Runs [poster]

995.4571 m/s [809 m/s] 749.3929 m/s [643.0 m/s] 

SR71 Record Speed Runs [poster]

812.3 m/s [805.6 m/s] 642.8 m/s [643.7 m/s] 

Detailed Crew Maps of the Flight Routes

812.3 m/s [805.6 m/s] 642.8 [643.7 m/s] 

"New York to London Speed Run Clarification There has been minor discrepancies both in SR71 publications and in data appearing on photos (to include the Lockheed photos on this web page) pertaining to the actual miles flown and the actual speed over the closed course. Major Jim Sullivan's certificate issued by the French Federation Aeronautique International (the governing body of aviation world records) reflects accurately the speed of 2,908.016 Kilometers Per Hour. Therefore: One statute mile = 1.609344 km. Therefore, 2908.016km/hr = 1806.957368 statute MI/hr. 1hr 54m 56.4s = 1.915666666hr. Rate times time = distance = 3,461.528 statute miles The correct New York to London Speed Run Data is: Time Flown: 1hour, 54min, 56.4sec Distance Flown: 3,461.528 statute miles Speed Flown: 1,806.957368 statute MI/hr. The correct London to Los Angeles Speed Run Data is: Time Flown: 3hour, 47min, 39 sec Distance Flown: 5,446.87 statute miles Speed Flown: 1,435.59 statute MI/hr." 
807.782 m/s 641.766 m/s 
Without a doubt, the SR71 Blackbird is the fastest and highest flying airplane currently in operation. From the late 1960s to the early 1990s, it routinely set speed and altitude records. Unfortunately for aeronautic historians, many of these records are mathematically inconsistent.
Average speed is distance divided by time. When applied to the historic flights cited above, this simple formula can be use to detect flaws is record keeping. For each of the record setting events, speed was calculated from the distance and time provided by the reporting website. On several occasions, this calculated value differed from the reported value. Whenever this happened, the calculated value was inserted in square brackets [like this].
Some of you reading this might take this as a slam against the Internet or the websites mentioned above, but this is not the case. The maps and posters cited at sr71.org were produced soon after the flights they are describing; presumably by LockheedMartin or US Air Force personnel. Somewhere back in the early history of these events someone got a little careless.
Possible sources of these inconsistencies include …
 transposition of digits (123 becomes 132, for example);
 sloppy conversions from nautical miles to miles to kilometers or knots to mph to km/h using approximate conversion factors for some calculations and more accurate ones later on;
 incorrect averaging of segments without weighting (1 km/h for 8 hours and 2 km/h for 2 hours does not average to 1.5 km/h, it averages to 1.2 km/h); or
 significant digit fiascoes, where rounded values are used to calculate results that are then reported with an unnaturally high degree of accuracy.
Once faulty data gets out, it's hard to recall. Error repeats error, repeats error, repeats error, …
Editor's Supplement  2003
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