supersonic

Perhaps the most extraordinary-looking aircraft to have taken to the air in many years, the X-59 Quiet Supersonic Technology experimental test aircraft, or QueSST, has made its first flight. Much is resting on the test program that has now been kicked off, with the future of supersonic passenger flight arguably dependent on its successful outcome.

The first flight took place at the U.S. Air Force’s Plant 42 in Palmdale, California. Photographer Matt Hartman has shared pictures with us of the X-59 after its departure from Plant 42, as seen at the top of this story and below.

It has been planned that after the X-59’s first flight, it will be moved to NASA’s Armstrong Flight Research Center, which is collocated with Edwards Air Force Base in California, for further test flights.

Ahead of the first flight, NASA had outlined its plans for the milestone sortie. This would be a lower-altitude loop at about 240 miles per hour to check system integration. It will be followed by the first phase of flight testing, focused on verifying the X-59’s airworthiness and safety. During subsequent test flights, the X-59 will go higher and faster, eventually exceeding the speed of sound.

Although there were no public announcements, the first flight had been expected earlier this month but was scrubbed for unknown reasons. TWZ has reached out to NASA for more information in relation to today’s flight.

A product of Lockheed Martin’s famed Skunk Works advanced projects division, the X-59 was rolled out at the Skunk Works facility within Palmdale in January 2024.

“In just a few short years, we’ve gone from an ambitious concept to reality,” NASA Deputy Administrator Pam Melroy said at the time. “NASA’s X-59 will help change the way we travel, bringing us closer together in much less time.”

The first flight was preceded by integrated systems testing, engine runs, and taxi testing.

Taxi tests began at Palmdale this summer, marking the first time that the X-59 had moved under its own power. NASA test pilot Nils Larson was at the controls for the aircraft’s first low-speed taxi test on July 10, 2025.

The X-59 project was kicked off back in 2016, and NASA had originally hoped that the aircraft would take to the air for the first time in 2020. The targeted first flight then slipped successively to 2023, to 2024, and then to this year.

Among other issues, NASA blamed the schedule slip on “several technical challenges identified over the course of 2023,” which the QueSST team then had to work through.

Once at Armstrong, the X-59 will be put through its paces as the centerpiece of NASA’s Quiet Supersonic Technology mission. This is an exciting project that TWZ has covered in detail over the years.

The main goal of QueSST is to prove that careful design considerations can reduce the noise of a traditional sonic boom to a “quieter sonic thump.” If that can then be ported over to future commercial designs, it could solve the longstanding problem of regulations that prohibit supersonic flight over land.

The only genuinely successful supersonic airliner was the Anglo-French Concorde. Even that aircraft had an abbreviated career, during which it struggled with enormously high operating costs and an ever-shrinking market.

Even before Concorde entered service, however, commercial supersonic flight over the United States had been prohibited, under legislation introduced in 1973. Even the U.S. military faces heavy restrictions on where and when it can operate aircraft above the speed of sound within national airspace. Similar prohibitions on supersonic flight exist in many other countries, too.

NASA’s test program aims to push the X-59 to a speed of Mach 1.4, equivalent to around 925 miles per hour, over land. At that point, it’s hoped that its unique design, shaping, and technologies will result in a much quieter noise signature.

The second phase of the QueSST program will be about ensuring that the core design works as designed and will include multiple sorties over the supersonic test range at Edwards Air Force Base.

The third and final phase will be the Community Response Study, in which the X-59 will be flown over different locations in the United States. Individuals in those different communities will provide feedback on the noise signature via push notifications to cell phones.

At one time, the third phase was planned to take place between 2025 and 2026, but, as previously outlined, the program as a whole has now been delayed.

In the past, we have looked at some of the remarkable features that make the X-59 a test jet like no other.

Most obviously, there is its incredibly long nose, which accounts for around a third of its overall length of 99.7 feet. Meanwhile, its wingspan measures just under 30 feet. The idea behind the thin, tapering nose, which you can read about in detail here, is that the shock waves that are created in and around the supersonic regime will be dissipated. It is these shock waves that would otherwise produce a very audible sonic boom on the ground.

The X-59’s nose also dictates its unusual cockpit arrangement, with the pilot being located almost halfway down the length of the aircraft, with no forward-facing window at all. The pilot instead relies on the eXternal Vision System (XVS), which was specially developed for the aircraft, to see the outside world. This makes use of a series of high-resolution cameras that feed into a 4K monitor in the cockpit, something that we have also discussed in depth in the past.

Another noteworthy feature is the location of the X-59’s powerplant, on top of the rear of the fuselage, which ensures a smooth underside. This is another part of the jet that has been tailored to address supersonic shockwaves, helping prevent them from merging behind the aircraft and causing a sonic boom. The powerplant itself is a single F414-GE-100 turbofan, a variant of the same engine found on the F/A-18E/F Super Hornet.

Meanwhile, various items found on the X-59 are more familiar. For example, the canopy and elements of the pilot’s seat are taken from the T-38 Talon, the landing gear is borrowed from an F-16, and the life-support system is adapted from that used in the F-15 Eagle.

If all proceeds as planned with the QueSST program, NASA should be able to demonstrate that the rules that currently prohibit commercial supersonic flight over land, both in the United States and elsewhere, can be adjusted.

However, whether that potential regulatory change is enough to spur the successful development of future commercial high-speed aircraft designs remains a big question.

After all, aside from Concorde, the quest to successfully introduce a supersonic passenger transport is one that has otherwise been littered with failures. Many will now be pinning their hopes on the X-59 helping to reverse that trend.

Update: 4:20 PM Eastern –

Lockheed Martin has now put out a press release about the X-59’s first flight. As planned, the aircraft has now arrived at NASA’s Armstrong Flight Research Center.

“The X-59 performed exactly as planned, verifying initial flying qualities and air data performance on the way to a safe landing at its new home,” according to the release. “Skunk Works will continue to lead the aircraft’s initial flight test campaign, working closely with NASA to expand the X-59’s flight envelope over the coming months. Part of this test journey will include the X-59’s first supersonic flights, where the aircraft will achieve the optimal speed and altitude for a quiet boom. This will enable NASA to operate the X-59 to measure its sound signature and conduct community acceptance testing.”

“We are thrilled to achieve the first flight of the X-59,” O.J. Sanchez, Vice President and General Manager of Lockheed Martin’s Skunk Works, said in a statement. “This aircraft is a testament to the innovation and expertise of our joint team, and we are proud to be at the forefront of quiet supersonic technology development.” 

“X-59 is a symbol of American ingenuity. The American spirit knows no bounds. It’s part of our DNA – the desire to go farther, faster, and even quieter than anyone has ever gone before,” Sean Duffy, Secretary of Transportation and acting NASA Administrator, also said in a statement. “This work sustains America’s place as the leader in aviation and has the potential to change the way the public flies.”

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American warships operating off Venezuela’s coast are not doing so without a credible threat. This comes from the presence of the Russian-made Kh-31 high-speed air-to-surface missile. Known to NATO as the AS-17 Krypton, the ramjet-powered weapon is available in both anti-radiation and anti-ship versions, with the ship-killer being the most relevant in this context. With this reality, combined with the steady drumbeat of reports raising the prospect of a military intervention of some kind in Venezuela, it’s worth looking closer at this unique capability within its arsenal.

While we have previously discussed in detail the different layers of Venezuela’s air defense system, it’s one of the key assets of its air force, the Aviación Militar Bolivariana Venezolana, AMBV, or Bolivarian Venezuelan Military Aviation, that is the launch platform for its Kh-31s. This is the Su-30MK2V Flanker multirole fighter, 24 of which were delivered between 2006 and 2008, and 21 of which survive in service today.

It should be noted that it’s not entirely clear whether Venezuela received both the anti-radiation Kh-31P and the anti-ship Kh-31A to arm its Su-30s. However, the Kh-31A, at least, appears to have been supplied, as seen in official videos showing AMBV Su-30s carrying the missiles while flying off the coast of Venezuela. Most recently, this kind of footage has been distributed by Caracas in an apparent statement of resolve against potential U.S. aggression. Venezuela has publicized its anti-ship quick reaction alert drills with these missiles in the past, as well. Moreover, the Kh-31P could also be used in anti-ship capacity, homing in on warships’ radars.

A video shows Venezuelan Su-30s using Kh-31s to launch a mock attack on a ship from an alert posture:

The development of the Kh-31 series of missiles began in the late 1970s in what was then the Soviet Union. The original requirement was for a high-speed anti-radiation missile that would be able to home in on and destroy the radars associated with then-new and emerging western air defense systems, such as the U.S. Army’s Patriot surface-to-air missile system and the U.S. Navy’s Aegis combat system.

The Kh-31A anti-ship missile entered production in 1990. Outside of Russia, it has proven an export success, with around a dozen operators, including China, India, and Vietnam.

Looking at the Kh-31A in more detail, it is fitted with an active radar seeker with a lock-on range of around 18 miles. The seeker works in both lock-on before and lock-on after launch modes. The missile also has a radio altimeter to ensure it can fly precisely at low altitude flight over water. All Kh-31s use a rocket-ramjet propulsion system to achieve sustained supersonic speeds. A rocket in the rear of the weapon boosts it to an optimal speed for the air-breathing ramjet to take over.

Combined with its high terminal speed, the Kh-31A has a penetration warhead, designed to punch through the side of a warship and detonate. This is in contrast to the high-explosive/fragmentation warhead in the Kh-31P. Making the missile harder to defeat is its ability to perform multi-axis maneuvers at up to 15G while skimming over the waves.

In terms of performance, the Kh-31A has a maximum range of 31 miles and a minimum launch distance of 9.3 miles. A longer-range version, the Kh-31AD, exists, with a maximum range of 75-100 miles, but it’s unclear if this was ever supplied to Venezuela.

The missile is accelerated to a speed of Mach 1.8 by means of a solid-propellant rocket booster; when the solid fuel is expended, the engine is ejected and the inside of the missile body is transformed into a combustion chamber for the ramjet, which accelerates the missile to Mach 3.5 at an altitude of 53,000 feet, or Mach 1.8 at sea level.

Each round weighs 1,323 pounds at launch, of which 192 pounds consists of the warhead. The Kh-31A is a notably big missile, with a total length of 15 feet 5 inches.

A good indicator of just how seriously the U.S. Navy takes the threat posed by the Kh-31A can be seen in its decision to buy the missiles from Russia and repurpose them as anti-ship missile targets to test the air defenses of its warships. The resulting target missile was known as the MA-31 and is a topic that we have written about in depth in the past.

Today, the Kh-31A may be old technology and also a weapon that the U.S. Navy has had first-hand experience of defeating (albeit in non-operational scenarios), however, its potency as an anti-ship weapon shouldn’t be underestimated.

This is true especially considering the variety of U.S. naval assets now sailing in relatively close proximity to Venezuela, in an operation aimed at putting pressure on Venezuelan President Nicolás Maduro. The Kh-31A is a threat to be taken seriously.

The U.S. naval presence in the region includes the Iwo Jima Amphibious Readiness Group (ARG)/22nd Marine Expeditionary Unit (MEU), with more than 4,500 sailors and Marines on three ships: The Wasp class amphibious assault ship, the USS Iwo Jima, and the San Antonio class amphibious transport dock ships, the USS San Antonio and USS Fort Lauderdale.

Also deployed in the region are several Arleigh Burke class guided missile destroyers, a Ticonderoga class guided missile cruiser, and the Ocean Trader, a shadowy special operations mothership. The presence of a cruiser, in particular, shadowing the Ocean Trader, underscores the fact that the Pentagon is taking the threat to this vessel very seriously. After all, the Ocean Trader has no organic defenses against anti-ship missiles and has, at times, operated very close to the Venezuelan coast.

As for the Arleigh Burkes, it is worth recalling that the Navy has already made efforts to bolster the defenses of some of these. Those that are forward-deployed to Rota, Spain, feature specific kinetic and non-kinetic systems to operate in the face of anti-ship cruise missiles in high-threat areas, including off the coast of Syria, but also in the Black Sea, which is a nearly land-locked super anti-ship missile engagement zone. Other electronic warfare upgrades continue on various surface combatants across the fleet, including some that are radical in scope.

While these ships are capable of dealing with Kh-31s, and the Navy has learned a lot when it comes to defending against complex attacks on their ships over the last couple of years, that doesn’t mean they can ignore them. Its speed leaves very little reaction time, especially considering early warning would be limited if the vessels were operating very close to the Venezuelan coastline.

Exactly what the U.S. plans to do with its military assets in regard to Maduro remains unclear. Back in August, as the military buildup gathered pace, U.S. officials told CNN that it had ordered naval movements in the region to contain the threat from drug-trafficking groups.

As we have outlined in the past, the deployment of an ARG and various surface combatants, as well as other high-end assets, sends a very strong signal to Maduro and the cartels. The Pentagon could carry out airstrikes or even put a limited number of boots on the ground from international waters in a hurry via special operations raids should President Donald Trump so decide. These may be aimed at cartels linked to Maduro and not the regime itself, but they still would be unprecedented.

Were such a military option to be launched, it would be possible that Venezuela’s Su-30s, armed with Kh-31A missiles, would be called into action, although targeting a U.S. Navy warship would be a huge deal, with massive repercussions.

In recent weeks, however, Venezuela has flown its fighters directly at U.S. warships, a Pentagon official having confirmed to TWZ that a pair of Venezuelan F-16s flew close to a U.S. Navy vessel in September, as you can read about here. Other similar instances have reportedly occurred. With U.S. Navy vessels operating close to the Venezuelan coast, there exists the very real possibility of a surprise attack on these ships as these close encounters would have put fighter aircraft within the Kh-31’s launch range.

Aside from the Su-30/Kh-31 combination, Venezuela’s anti-ship missile capabilities are currently fairly limited.

The Venezuelan Navy has a single operational Mariscal Sucre class frigate, the Almirante Brión, part of a group of warships that were commissioned in the early 1980s. The Italian-made warship was supplied armed with eight launchers for Otomat Mk 2 anti-ship missiles. The same missiles, in twin launchers, were fitted to the Venezeulan Navy’s Constitución class fast attack craft, of which three are reportedly still operational.

Italy also supplied Venezuela with Sea Killer anti-ship missiles, which armed Venezuelan Navy AB.212 helicopters, several of which remain active, although primarily now used for assault and logistics missions.

The operational status of these Italian-made systems should be considered questionable. Even if still serviceable, they are a far less threatening proposition than the Kh-31A. Both missiles have subsonic performance. The Otomat Mk 2 has a range of around 110 miles, while the Sea Killer can hit targets out to a range of around 6.2 miles.

More recent anti-ship missile deliveries comprise the Iranian-made CM-90 (an export version of the Nasr) that were supplied by Tehran along with Peykaap III (Zolfaghar class) fast attack craft. These are also subsonic weapons.

The Venezuela Navy deployed Iranian-built Peykaap-III (Zolfaghar-class) fast attack craft equipped with CM-90 Anti-Ship Missiles (ASCM) supplied by Iran. pic.twitter.com/vc2aiSIKxI

— OSINTWarfare (@OSINTWarfare) September 6, 2025

Although the U.S. Navy is now much more familiar with the threat posed by the AS-17 Krypton, and while its warships are fitted with air defense systems that are capable of dealing with just such a threat, among others, this remains a very potent weapon.

If Venezuela were to directly attack an American warship, it would very likely result in being at war with the United States. But if the regime was already in such a predicament, or if it was facing imminent collapse, such an act could become a greater possibility.

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