NASA's F-15B testbed aircraft undergoes pre-flight checks before performing the first flight of the Quiet Spike project. The first flight was performed for evaluation purposes, and the spike was not extended. The Quiet Spike was developed as a means of controlling and reducing the sonic boom caused by an aircraft 'breaking' the sound barrier.

Gulfstream Aerospace and NASA's Dryden Flight Research Center are testing the structural integrity of a telescopic 'Quiet Spike' sonic boom mitigator on the F-15B testbed. The Quiet Spike was developed as a means of controlling and reducing the sonic boom caused by an aircraft 'breaking' the sound barrier.

NASA's F-15B testbed aircraft lands after the first flight of the Quiet Spike project. The first flight was performed for evaluation purposes, and the spike was not extended. The Quiet Spike was developed as a means of controlling and reducing the sonic boom caused by an aircraft 'breaking' the sound barrier.

Approaching the runway after the first evaluation flight of the Quiet Spike project, NASA's F-15B testbed aircraft cruises over Roger's Dry Lakebed near the Dryden Flight Research Center. The Quiet Spike was developed by Gulfstream Aerospace as a means of controlling and reducing the sonic boom caused by an aircraft 'breaking' the sound barrier.

NASA's 2017 astronaut candidates (L to R) Zena Cardman, Loral O'Hara, Frank Rubio, Jonny Kim, Raja Chari practice flying in an X-59 QueSST simulator at Armstrong Flight Research Center, in Southern California. The low boom flight demonstrator, X-59, being built at Lockheed Martin and was designed to fly at supersonic speeds over land without the loud noise of breaking the sound barrier and disturbing communities.

NASA's 2017 astronaut candidate Kayla Barron practices flying in an X-59 QueSST simulator at Armstrong Flight Research Center, in Southern California. The low boom flight demonstrator, X-59, being built at Lockheed Martin and was designed to fly at supersonic speeds over land without the loud noise of breaking the sound barrier and disturbing communities.

NASA's 2017 astronaut candidate Kayla Barron practices flying in an X-59 QueSST simulator at Armstrong Flight Research Center, in Southern California. The low boom flight demonstrator, X-59, being built at Lockheed Martin and was designed to fly at supersonic speeds over land without the loud noise of breaking the sound barrier and disturbing communities.

NASA's 2017 astronaut candidate Kayla Barron practices flying in an X-59 QueSST simulator at Armstrong Flight Research Center, in Southern California. The low boom flight demonstrator, X-59, being built at Lockheed Martin and was designed to fly at supersonic speeds over land without the loud noise of breaking the sound barrier and disturbing communities.

NASA's 2017 astronaut candidate Kayla Barron practices flying in an X-59 QueSST simulator at Armstrong Flight Research Center, in Southern California. The low boom flight demonstrator, X-59, being built at Lockheed Martin and was designed to fly at supersonic speeds over land without the loud noise of breaking the sound barrier and disturbing communities.

NASA’s 2017 astronaut candidates (L to R) Jonny Kim and Raja Chari practice flying in an X-59 QueSST simulator at Armstrong Flight Research Center, in Southern California. The low boom flight demonstrator, X-59, being built at Lockheed Martin and was designed to supersonically over land without the loud noise of breaking the sound barrier and disturbing communities.

NASA’s X-59 quiet supersonic research aircraft sits on the ramp at Lockheed Martin Skunk Works in Palmdale, California during sunrise, shortly after completion of painting. With its unique design, including a 38-foot-long nose, the X-59 was built to demonstrate the ability to fly supersonic, or faster than the speed of sound, while reducing the typically loud sonic boom produced by aircraft at such speeds to a quieter sonic “thump”. The X-59 is the centerpiece of NASA’s Quesst mission, which seeks to solve one of the major barriers to supersonic flight over land, currently banned in the United States, by making sonic booms quieter.

NASA’s X-59 quiet supersonic research aircraft sits on the ramp at Lockheed Martin Skunk Works in Palmdale, California during sunrise, shortly after completion of painting. With its unique design, including a 38-foot-long nose, the X-59 was built to demonstrate the ability to fly supersonic, or faster than the speed of sound, while reducing the typically loud sonic boom produced by aircraft at such speeds to a quieter sonic “thump”. The X-59 is the centerpiece of NASA’s Quesst mission, which seeks to solve one of the major barriers to supersonic flight over land, currently banned in the United States, by making sonic booms quieter.

NASA test pilot Nils Larson gets an initial look at the painted X-59 as it sits on the ramp at Lockheed Martin Skunk Works in Palmdale, California. Larson, one of three test pilots training to fly the X-59 inspects the side of the 38-foot-long nose; a primary design feature to the X-59’s purpose of demonstrating the ability to fly supersonic, or faster than sound, without creating a loud sonic boom. The X-59 is the centerpiece of NASA’s Quesst mission, which seeks to solve one of the major barriers to supersonic flight over land, currently banned in the United States, by making sonic booms quieter.

NASA’s X-59 quiet supersonic research aircraft sits on the ramp at Lockheed Martin Skunk Works in Palmdale, California during sunrise, shortly after completion of painting. With its unique design, including a 38-foot-long nose, the X-59 was built to demonstrate the ability to fly supersonic, or faster than the speed of sound, while reducing the typically loud sonic boom produced by aircraft at such speeds to a quieter sonic “thump”. The X-59 is the centerpiece of NASA’s Quesst mission, which seeks to solve one of the major barriers to supersonic flight over land, currently banned in the United States, by making sonic booms quieter.

NASA test pilot Nils Larson gets an initial look at the painted X-59 as it sits on the ramp at Lockheed Martin Skunk Works in Palmdale, California. Larson, one of three test pilots training to fly the X-59 inspects the side of the 38-foot-long nose; a primary design feature to the X-59’s purpose of demonstrating the ability to fly supersonic, or faster than sound, without creating a loud sonic boom. The X-59 is the centerpiece of NASA’s Quesst mission, which seeks to solve one of the major barriers to supersonic flight over land, currently banned in the United States, by making sonic booms quieter.

NASA’s X-59 quiet supersonic research aircraft sits on the ramp at Lockheed Martin Skunk Works in Palmdale, California during sunrise, shortly after completion of painting. With its unique design, including a 38-foot-long nose, the X-59 was built to demonstrate the ability to fly supersonic, or faster than the speed of sound, while reducing the typically loud sonic boom produced by aircraft at such speeds to a quieter sonic “thump”. The X-59 is the centerpiece of NASA’s Quesst mission, which seeks to solve one of the major barriers to supersonic flight over land, currently banned in the United States, by making sonic booms quieter.

NASA’s X-59 quiet supersonic research aircraft sits on the ramp at Lockheed Martin Skunk Works in Palmdale, California during sunrise, shortly after completion of painting. With its unique design, including a 38-foot-long nose, the X-59 was built to demonstrate the ability to fly supersonic, or faster than the speed of sound, while reducing the typically loud sonic boom produced by aircraft at such speeds to a quieter sonic “thump”. The X-59 is the centerpiece of NASA’s Quesst mission, which seeks to solve one of the major barriers to supersonic flight over land, currently banned in the United States, by making sonic booms quieter.

NASA’s X-59 quiet supersonic research aircraft sits on the ramp at Lockheed Martin Skunk Works in Palmdale, California during sunrise, shortly after completion of painting. With its unique design, including a 38-foot-long nose, the X-59 was built to demonstrate the ability to fly supersonic, or faster than the speed of sound, while reducing the typically loud sonic boom produced by aircraft at such speeds to a quieter sonic “thump”. The X-59 is the centerpiece of NASA’s Quesst mission, which seeks to solve one of the major barriers to supersonic flight over land, currently banned in the United States, by making sonic booms quieter.

NASA image acquired June 26, 2010 As of June 27, 2010, the entire gulf-facing beachfront of several barrier islands in eastern Mississippi (offshore of Pascagoula) had received a designation of at least “lightly oiled” by the interagency Shoreline Cleanup Assessment Team that is responding to the disaster in the Gulf of Mexico. A few small stretches of Petit Bois Island had been labeled heavily or moderately oiled. (To view this image without a description go to: This high-resolution image shows Petit Bois Island (top right) and the eastern end of Horn Island (top left) on June 26. In general, oil-covered waters are silvery and cleaner waters are blue-gray. This pattern is especially consistent farther from the islands. The intensely bright patches of water directly offshore of the barrier islands, however, may be from a combination of factors, including sediment and organic material, coastal currents and surf, and oil. The islands provide a sense of scale for the ribbons of oil swirling into the area from the south. Petit Bois Island is about 10 kilometers (6 miles) long. It is one of seven barrier islands that, along with some mainland areas of Mississippi and Florida, make up the Gulf Islands National Seashore. According to the National Park Service Gulf Islands National Seashore Website, all the islands remained open to the public as of June 28, 2010, and clean-up crews were on hand to respond to any oil coming ashore. The large version of this image, which was captured by the Advanced Land Imager on NASA’s Earth Observing-1 (EO-1) satellite, shows a larger area, including the Mississippi Sound and parts of mainland Mississippi. Although oil has been observed in the Sound, it is unlikely that all the bright patches of water in that area are thickly oil-covered. Differences in brightness in coastal area waters may be due to other factors, including freshwater runoff, strong currents, and water depth and clarity. NASA Earth Observatory image created by Jesse Allen and Robert Simmon, using EO-1 ALI data provided courtesy of the NASA EO-1 team. Caption by Rebecca Lindsey. Instrument: EO-1 - ALI To see more images go to: <a href="http://earthobservatory.nasa.gov/" rel="nofollow">earthobservatory.nasa.gov/</a> <b><a href="http://www.nasa.gov/centers/goddard/home/index.html" rel="nofollow">NASA Goddard Space Flight Center</a></b> is home to the nation's largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA's quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft's journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin's Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA's quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft's journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin's Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA's quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft's journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin's Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA's quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft's journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin's Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

The engine that will power NASA’s quiet supersonic X-59 in flight is installed, marking a major milestone in the experimental aircraft’s journey toward first flight. The installation of the F414-GE-100 engine at Lockheed Martin’s Skunk Works facility brings the vehicle close to the completion of its assembly.

STS083-712-063 (4-8 April 1997) --- Northern half of Long Island, Bahamas. The vivid blues of the Bahamas stand out from space. Long Island and Great Exuma Island, which extends from the west north west into the photo, is on the eastern side of the Great Bahama Bank and form the borders of Exuma Sound. This photograph provides a rare opportunity to observe a natural chemical laboratory at work. Limestone of quite a different sort from that forming the Great Barrier Reef is actually in the process of formation. Long Island itself is little more than a sandbar rising just a few meters (about 30 to 50 meters) above sea level but it separates the deep, dark blue waters of the Atlantic on the right from the 10-meter (33 feet) shallows of the Great Bahama Bank (left). Details of the topography of the bank are visible through the clear waters. The shallow waters are warm and become extremely salty. Crystals of aragonite, a calcium carbonate mineral, are precipitated and formed into spherical sand-sized oolites as the tidal currents swirl back and forth. Lithification of the carbonate sands produces an oolithic limestone. Although the water is warm and clear, corals do not live in the shallows, probably because of the elevated salt content. Although chemically similar, the oolithic limestone forming Long Island is very different from coral reef limestone. An airfield is visible at the northern and central (bottom of photo) part of the island.

The Aircraft Engine Research Laboratory’s pilot corps during the final days of World War II: from left to right, Joseph Vensel, Howard Lilly, William Swann, and Joseph Walker. William “Eb” Gough joined the group months after this photograph. These men were responsible for flying the various National Advisory Committee for Aeronautics (NACA) aircraft to test new engine modifications, study ice buildup, and determine fuel performance. Vensel, a veteran pilot from Langley, was the Chief of Flight Operations and a voice of reason at the laboratory. In April 1947 Vensel was transferred to lead the new Muroc Flight Tests Unit in California until 1966. Lilly was a young pilot with recent Navy experience. Lilly also flew in the 1946 National Air Races. He followed Vensel to Muroc in July 1947 where he became the first NACA pilot to penetrate the sound barrier. On May 3, 1948, Lilly became the first NACA pilot to die in the line of duty. Swann was a young civilian pilot when he joined the NACA. He spent his entire career at the Cleveland laboratory, and led the flight operations group from the early 1960s until 1979. Two World War II veterans joined the crew after the war. Walker was a 24-year-old P–38 reconnaissance pilot. He joined the NACA as a physicist in early 1945 but soon worked his way into the cadre of pilots. Walker later gained fame as an X-plane pilot at Muroc and was killed in a June 1966 fatal crash. Gough survived being shot down twice during the war and was decorated for flying rescue missions in occupied areas.

A researcher examines a model being installed in the test section of the 10- by 10-Foot Supersonic Wind Tunnel during the 1957 Inspection of the National Advisory Committee for Aeronautics (NACA) Lewis Flight Propulsion Laboratory. The NACA held its annual Inspection at one of its three research laboratories. Representatives from the military, aeronautical industry, universities, and the press were invited to the laboratory to be briefed on the NACA’s latest research efforts and tour the state- of- the- art test facilities. Over 1700 people visited the NACA Lewis in Cleveland, Ohio during the October 7 - 10, 1957 Inspection. NACA researchers Leonard Obery, seen here, James Connors, Leonard, Stitt, David Bowditch gave presentations on high Mach number turbojets at the 10- by 10 tunnel. It had been only 15 years since a jet aircraft had first flown in the US. Since then the sound barrier had been broken and speeds of Mach 2.5 had been achieved. In the late 1950s NACA researchers sought to create an engine that could achieve Mach 4. This type of engine would require an extremely long inlet and nozzle which would have to be capable of adjusting their diameter for different speeds. A Mach 4 engine would require new composite materials to withstand the severe conditions, modified airframes to hold the longer engines, and high temperature seals and lubricants. The 10- by 10-foot tunnel, which had only been in operation for a year and a half, would play a critical role in these studies. NACA researchers at other facilities discussed high energy aircraft fuels and rocket propellants, aircraft noise reduction, hypersonic flight, nuclear propulsion, and high temperature materials.

This pair of images of the Long Island, New York region is a comparison of an optical photograph (top) and a radar image (bottom), both taken in darkness in April 1994. The photograph at the top was taken by the Endeavour astronauts at about 3 a.m. Eastern time on April 20, 1994. The image at the bottom was acquired at about the same time four days earlier on April 16,1994 by the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) system aboard the space shuttle Endeavour. Both images show an area approximately 100 kilometers by 40 kilometers (62 miles by 25 miles) that is centered at 40.7 degrees North latitude and 73.5 degrees West longitude. North is toward the upper right. The optical image is dominated by city lights, which are particularly bright in the densely developed urban areas of New York City located on the left half of the photo. The brightest white zones appear on the island of Manhattan in the left center, and Central Park can be seen as a darker area in the middle of Manhattan. To the northeast (right) of the city, suburban Long Island appears as a less densely illuminated area, with the brightest zones occurring along major transportation and development corridors. Since radar is an active sensing system that provides its own illumination, the radar image shows a great amount of surface detail, despite the night-time acquisition. The colors in the radar image were obtained using the following radar channels: red represents the L-band (horizontally transmitted and received); green represents the L-band (horizontally transmitted and vertically received); blue represents the C-band (horizontally transmitted and vertically received). In this image, the water surface - the Atlantic Ocean along the bottom edge and Long Island Sound shown at the top edge - appears red because small waves at the surface strongly reflect the horizontally transmitted and received L-band radar signal. Networks of highways and railroad lines are clearly visible in the radar image; many of them can also be seen as bright lines i the optical image. The runways of John F. Kennedy International Airport appear as a dark rectangle in Jamaica Bay on the left side of the image. Developed areas appear generally as bright green and orange, while agricultural, protected and undeveloped areas appear darker blue or purple. This contrast can be seen on the barrier islands along the south coast of Long Island, which are heavily developed in the Rockaway and Long Beach areas south and east of Jamaica Bay, but further to the east, the islands are protected and undeveloped. http://photojournal.jpl.nasa.gov/catalog/PIA01785

NASA Armstrong Flight Research Center test pilots Jim "Clue" Less (front) and Wayne "Ringo" Ringelberg (back) taxi out in a NASA F/A-18 at Ellington Field in Houston, Texas, in preparation of a training flight for the Quiet Supersonic Flights 2018 series, or QSF18. The QSF18 flights will provide NASA with feedback necessary to validate community response techniques for future quiet supersonic research flights for the X-59 Quiet SuperSonic Technology, or QueSST.

The Bell Aircraft Corporation X-1-2 aircraft on the ramp at NACA High Speed Flight Research Station located on the South Base of Muroc Army Air Field in 1947. The X-1-2 flew until October 23, 1951, completing 74 glide and powered flights with nine different pilots. The aircraft has white paint and the NACA tail band. The black Xs are reference markings for tracking purposes. They were widely used on NACA aircraft in the early 1950s.

This photo of the X-1A includes graphs of the flight data from Maj. Charles E. Yeager's Mach 2.44 flight on December 12, 1953. (This was only a few days short of the 50th anniversary of the Wright brothers' first powered flight.) After reaching Mach 2.44, then the highest speed ever reached by a piloted aircraft, the X-1A tumbled completely out of control. The motions were so violent that Yeager cracked the plastic canopy with his helmet. He finally recovered from a inverted spin and landed on Rogers Dry Lakebed. Among the data shown are Mach number and altitude (the two top graphs). The speed and altitude changes due to the tumble are visible as jagged lines. The third graph from the bottom shows the G-forces on the airplane. During the tumble, these twice reached 8 Gs or 8 times the normal pull of gravity at sea level. (At these G forces, a 200-pound human would, in effect, weigh 1,600 pounds if a scale were placed under him in the direction of the force vector.) Producing these graphs was a slow, difficult process. The raw data from on-board instrumentation recorded on oscillograph film. Human computers then reduced the data and recorded it on data sheets, correcting for such factors as temperature and instrument errors. They used adding machines or slide rules for their calculations, pocket calculators being 20 years in the future.