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Aug 3, 2024, 5:51:06 PM8/3/24

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NASA will deliver the results to U.S. and international regulators, who will consider new rules that would lift the ban that has been in place for so long. The goal is for a regulatory shift that focuses on the sound an aircraft creates, instead of a speed limit.

The origins of the federal ban on supersonic flight go back to 1947, the first time the rocket-powered XS-1 airplane broke the sound barrier and initiated the heroic era of faster-than-sound research.

Despite early interest in what was then a mysterious phenomenon created as an airplane flies faster than the speed of sound and generate atmospheric shock waves we hear as sonic booms, there were few tools and only limited data available to help understand what was happening.

But as the Air Force and Navy began to deploy large numbers of supersonic jets at bases around the nation, interest in sonic booms quickly grew as more of the public became exposed to the often-alarming noise.

Beginning in 1956 and continuing well into the 1960s, the Air Force, Navy, NASA, and the Federal Aviation Administration (FAA) employed resources to study how sonic booms formed under various conditions, what their effects might be on buildings, and how the public would react in different locations.

Through those years, using many types of supersonic jets, residents of Atlanta, Chicago, Dallas, Denver, Los Angeles, and Minneapolis, among others, all were exposed to sonic booms from military fighter jets and bombers flying overhead at high altitude.

The SST project aimed to produce the prototype for a new commercial supersonic airliner, capable of carrying as many as 300 passengers anywhere in the world at speeds as great as three times the speed of sound.

Within a couple of years, the FAA formally proposed a rule that would restrict operation of civil aircraft at speeds greater than Mach 1. Then in May of 1971 Congress cancelled the SST program and the rule banning civil supersonic flights over land went into effect two years later.

During this same time, Great Britain and France were developing and test flying the Concorde, which went on to provide commercial supersonic air travel between 1976 and 2003. There were many reasons for its demise, including a deadly crash in 2000, but economic and environmental issues top the list. Restrictions against flying faster than sound over land due to the ban in the U.S. and elsewhere greatly limited its revenue-generating options.

So, you've just put the finishing touches on upgrades to your spaceship, and now it can fly at almost the speed of light. We're not quite sure how you pulled it off, but congratulations!

Before you fly off on your next vacation, however, watch this handy video to learn more about near-light-speed safety considerations, travel times, and distances between some popular destinations around the universe.

You can also download shorter clips from the video and printable postcards to send to your friends. Near-light-speed Travel GuideThis handy video will help acquaint you with the quirks of near-light-speed travel, expected travel times, and the distances to some popular (at least, we think so) destinations!Credit: NASA's Goddard Space Flight CenterMusic: "The Tiptoe Strut" from Universal Production MusicComplete transcript available.

Near-light-speed Travel GuideThis handy video will help acquaint you with the quirks of near-light-speed travel, expected travel times, and the distances to some popular (at least, we think so) destinations!Credit: NASA's Goddard Space Flight CenterMusic: "The Tiptoe Strut" from Universal Production MusicComplete transcript available. Near Light Speed 101: Effects of Near-light-speed TravelTravel at near the speed of light offers a few quirks you should be aware of, from time and space weirdness to protecting yourself from dangerous cosmic particles. This video covers some of the important ones!Credit: NASA's Goddard Space Flight CenterMusic: "Dinner With the Vicar" from Universal Production MusicComplete transcript available.

Near Light Speed 101: Effects of Near-light-speed TravelTravel at near the speed of light offers a few quirks you should be aware of, from time and space weirdness to protecting yourself from dangerous cosmic particles. This video covers some of the important ones!Credit: NASA's Goddard Space Flight CenterMusic: "Dinner With the Vicar" from Universal Production MusicComplete transcript available. Near Light Speed 101: Near-light-speed Travel TimesEven if you've figured out how to travel at almost the speed of light, the universe is still a huge place! Watch this video to learn more about how long it takes to cruise around the cosmos.Credit: NASA's Goddard Space Flight CenterMusic: "Dinner With the Vicar" from Universal Production MusicComplete transcript available.

PASADENA, Calif.-- Deep in the heart of the asteroid belt, on its way to the first of the belt's two most massive inhabitants, NASA's ion-propelled Dawn spacecraft has eclipsed the record for velocity change produced by a spacecraft's engines.

The previous standard-bearer for velocity change, NASA's Deep Space 1, also impelled by ion propulsion, was the first interplanetary spacecraft to use this technology. The Deep Space 1 record fell on Saturday, June 5, when the Dawn spacecraft's accumulated acceleration over the mission exceeded 4.3 kilometers per second (9,600 miles per hour).

"We are using this amazing ion-engine technology as a stepping-stone to orbit and explore two of the asteroid belt's most mysterious objects, Vesta and Ceres," said Robert Mase, Dawn project manager from NASA's Jet Propulsion Laboratory in Pasadena, Calif.

A spacecraft's change in velocity refers to its ability to change its path through space by using its own rocket engines. This measurement of change begins only after the spacecraft exits the last stage of the launch vehicle that hurled it into space.

To get to where it is in both the record books and the asteroid belt, the Dawn spacecraft had to fire its three engines - one at a time-- for a cumulative total of 620 days. In that time, it has used less than 165 kilograms (363 pounds) of xenon propellant. Over the course of its eight-plus-year mission, Dawn's three ion engines are expected to accumulate 2,000 days of operation -- 5.5 years of thrusting -- for a total change in velocity of more than 38,620 kilometers per hour (24,000 miles per hour).

"I am delighted that it will be Dawn that surpasses DS1's record," said Marc Rayman, chief engineer for the Dawn mission and a previous project manager for Deep Space 1."It is a tribute to all those involved in the design and operations of this remarkable spacecraft."

At first glance, Dawn's pedal-to-the-metal performance is a not-so-inspiring 0-to-97 kilometers per hour (0-to-60 miles per hour) in four days. But due to its incredible efficiency, it expends only 37 ounces of xenon propellant during that time. Then take into consideration that after those four days of full-throttle thrusting, it will do another four days, and then another four. By the end of 12 days, the spacecraft will have increased its velocity by more than 290 kilometers per hour (180 miles per hour), with more days and weeks and months of continuous thrusting to come. In one year's time, Dawn's ion propulsion system can increase the spacecraft's speed by 8,850 kilometers per hour (5,500 miles per hour), while consuming the equivalent of only 16 gallons of fuel.

"This is a special moment for the spacecraft team," said Dawn's principal investigator, Chris Russell of the University of California Los Angeles. "In only 407 days, our minds will be on another set of records, the data records that Dawn will transmit when we enter Vesta orbit."

Dawn's 4.8-billion-kilometer (3-billion-mile) odyssey includes exploration of asteroid Vesta in 2011 and 2012, and the dwarf planet Ceres in 2015. These two icons of the asteroid belt have been witness to much of our solar system's history. By using the same set of instruments at two separate destinations, scientists can more accurately formulate comparisons and contrasts. Dawn's science instrument suite will measure shape, surface topography and tectonic history, elemental and mineral composition, as well as seek out water-bearing minerals. In addition, the way the Dawn spacecraft orbits both Vesta and Ceres will be used to measure the celestial bodies' masses and gravity fields.

While Dawn surpassed Deep Space 1's record for velocity change, Deep Space 1 will continue to reign as holder for the longest duration of powered spaceflight for another few months. Dawn is expected to take over that record on about August 10 of this year.

The Dawn mission to Vesta and Ceres is managed by JPL, a division of the California Institute of Technology in Pasadena, for NASA's Science Mission Directorate, Washington. The University of California, Los Angeles, is responsible for overall Dawn mission science. Other scientific partners include Planetary Science Institute, Tucson, Ariz.; Max Planck Institute for Solar System Research, Katlenburg-Lindau, Germany; DLR Institute for Planetary Research, Berlin, Germany; Italian National Institute for Astrophysics, Rome; and the Italian Space Agency, Rome. Orbital Sciences Corporation of Dulles, Va., designed and built the Dawn spacecraft.

The original Common Research Model was the high speed version which was developed in response to a need for a generic but relevant high speed transport geometry that could be used by anyone without any restrictions.

The Scaled Power ElectrifiEd Drivetrain (SPEED) is a low-power, direct current (DC), single-string testbed which uses a dynamometer as a load and can support power levels up to 9 kilowatts (kW). SPEED helps familiarize NASA engineers with electrified aircraft-related powertrains and is used to verify operations and characterize motor and inverter components before integration into the Advanced Reconfigurable Electrified Aircraft Lab (AREAL), a 200-kW high-power testbed with DC and motor emulators for reconfiguration capabilities.