Aerospace Legacy Foundation

Your portal to America's aerospace history

Aerospace Legacy Foundation (ALF) is a community based non-profit organization (501c3) including aerospace retirees and the public at large. Preserving Southern California's Aerospace and Aviation History including Downey's aerospace legacy.

Hyper Sonic

Boeing unveils its ‘Son of Blackbird’ HYPER-SONIC spy plane concept that could travel at 3,800 mph

Boeing has finally unveiled the potential successor to the legendary Blackbird SR-71 spy plane (pictured)- and it is set to travel at more than five times the speed of sound.

Boeing has finally unveiled the potential successor to the legendary Blackbird SR-71 spy plane (pictured)- and it is set to travel at more than five times the speed of sound.

"Boeing has finally unveiled a concept for the potential successor to the legendary Blackbird SR-71 spy plane - and it is set to travel at more than five times the speed of sound. This 'Son of Blackbird' could become a high-speed strike and reconnaissance aircraft in warfare of the future, travelling at such speeds that adversaries would have no time to react or hide.

It is designed to carry out spy missions in the same way as the Blackbird SR-71, which was the world's fastest and highest-flying operational manned aircraft throughout its career. In 1976 it set an absolute speed record of 2,193.2mph (3,529kmh) - a record it still holds today." From The Daily Mail 


Skunk Works

Skunk Works

Skunk Works Lockheed SR-72

Skunk Works Lockheed SR-72

“The Lockheed Martin SR-72 is an American conceptualized hypersonic UAV intended for intelligence, surveillance and reconnaissance privately proposed to succeed the retired Lockheed SR-71 Blackbird”. Wiki

Lockheed SR-72 concept

Lockheed SR-72 concept

A Lockheed Martin executive hinted at a recent aerospace conference that the SR-72, the hypersonic successor to the SR-71 Blackbird, may already exist, according to Bloomberg.

Jack O'Banion, a vice president at Lockheed's Skunk Works, made mysterious comments about the ultra-secret project at the American Institute of Aeronautics and Astronautics' annual SciTech Forum.

O'Banion said that new design tools and more powerful computers brought about a "digital transformation" and "without [that] digital transformation, the aircraft you see there could not have been made," Bloomberg's Justin Bachman reported, adding that O'Banion then showed a slide of the SR-72.

This digital transformation reportedly gave Lockheed the ability to design a three-dimensional scramjet engine. Scramjet is a kind of ramjet air-breathing jet engine where combustion happens at supersonic speeds. More

Daniel Brown- Business Insider Jan. 22, 2018, 1:29 PM

SR-72 (1).jpg

Video- Lockheed Martin's mysterious SR-72 — the fastest plane ever

“The basic physics of hypersonic flight have been understood for decades, with the Air Force and NASA flying the rocket-powered X-15 in the 1960s above Mach 6 and the X-43A hitting Mach 9.6 in 2004. More recently, Boeing Co. flew an experimental craft, the X-51 WaveRider, to Mach 5.1 in May 2013”. Stars and Stripes

SR-72 by Lockheed. Image- The Drive

SR-72 by Lockheed. Image- The Drive

Bye, Bye Blackbird?


“Unofficially, the SR-71 carried many nicknames, including the "Habu,"  "SR," "Lady in Black," and "Sled;" but most of us know the SR-71 as the "Blackbird." The SR-71 was developed as a long-range strategic reconnaissance aircraft capable of flying at speeds over Mach 3.2 and at 85,000 feet. The first SR-71 to enter service was delivered in 1966 and due to politics, it was retired in 1990. However, the USAF still kept a few SR-71s in operation up until 1998, after a few were brought back to service in 1995. NASA's DFRC at Edwards AFB, CA flew the SR-71 from 1991 until its final flight in October 1999 “ . SR-71 .org


“The Blackbirds were designed to cruise at Mach 3.2, just over three times the speed of sound or more than 2,200 miles per hour and at altitudes up to 85,000 feet. The extreme operating environment in which they flew made the aircraft excellent platforms for conducting research and experiments in a variety of disciplines: aerodynamics, propulsion, structures, thermal protection materials, high-speed and high-temperature instrumentation, atmospheric studies, and sonic boom characterization.” NASA

NASA Armstrong Fact Sheet: SR-71 Blackbird

“SR-71 Development and Operations:

The SR-71 Blackbird is one of the most spectacular aircraft ever built. It is a long-range, supersonic reconnaissance aircraft capable of flying at Mach 3.2. When it first flew, it was an amazing performer and still is after three decades of unmatched capabilities.

The SR-71 has serviced the United States for more than 35 years. During that time, it has had a very interesting history. It all began back in the mid 1950s when the United States Air Force and the CIA decided that it would be best to replace the U-2, an aircraft with something that would travel much faster and higher to avoid enemy defenses. Lockheed, the developer of the U-2 was also given the contract to develop this supersonic aircraft after a competition with Convair. The project was called ARCHANGEL and the Skunk Works, a division of the Lockheed Aircraft Corporation went through twelve design proposals before they reached their final design, the A-12. Read more here

“Two Pratt & Whitney J58 axial-flow turbojets with afterburners, each producing 32,500 lb of thrust, powered the Blackbirds. Less than 20 percent of the total thrust used to fly at Mach 3 was produced by the engine itself, however. During high-speed cruise conditions the balance of total thrust was produced by the unique design of the engine inlet and a moveable conical spike at the front of each engine nacelle. Under these conditions, air entering the inlets bypassed the engines, going directly to the afterburners and ejector nozzles, thus acting as ramjets.

The airframes were built almost entirely of titanium and other exotic alloys to withstand heat generated by sustained high-speed flight. Capable of cruising at Mach 3 continuously for more than one hour at a time, the Blackbirds provided a unique research platform for thermal experiments because heat-soak temperatures exceeded 600 °F.

The aircraft was 107.4 feet (32.73 meters) long, had a wingspan of 55.6 feet (16.94 meters), and stood 18.5 feet (5.63 meters) high (from the ground to the top of the rudders when parked). Gross takeoff weight was about 140,000 lb (52,253.83 kilograms), including a fuel weight of 80,000 lb (29,859.33 kilograms). Aerodynamic control surfaces consisted of all-moving vertical tail fins above each engine nacelle and elevons on the outer wings and trailing edges between the engine exhaust nozzles.

NASA crews flew four Lockheed SR-71 airplanes during the 1990s. Two were used for research and two to support Air Force reactivation of the SR-71 for reconnaissance missions. Although the Air Force retired the Blackbirds in 1990, Congress reinstated funding for additional flights several years later. SR-71A (61-7980/NASA 844) arrived at Dryden on Feb. 15, 1990. It was placed into storage until 1992 and served as a research platform until its final flight on Oct. 9, 1999. SR-71A (61-7971/NASA 832) arrived at Dryden on March 19, 1990, but was returned to Air Force inventory as the first aircraft was reactivated in 1995. Along with SR-71A (61-7967), it was flown by NASA crews in support of the Air Force program. SR-71B (61-7956/NASA 831) arrived at Dryden on July 25, 1991, and served as a research platform as well as for crew training and proficiency until October 1997”. NASA

“The SR-71 is the fastest and highest flying production aircraft in the world. The only aircraft that is faster is the X-15 that can reach a speed of over 4,000 mph. The only aircraft ever to come close to the SR-71's speed besides the X-15 is the Russian MiG-25 Foxbat. The MiG-25 could only reach speeds of over Mach 3 for a few minutes. The Anglo-French Concorde is the only aircraft besides the SR-71 that can fly at supersonic speeds for hours at a time”. NASA

sr 71.jpg

“Because of such high altitudes, temperatures and speeds, titanium alloy was the only material that suited the plane’s mission. Over 90 percent of the SR-71 was made of titanium alloy. Factor in glass for the cockpit and landing gear material – that means basically the whole aircraft was titanium alloy. Titanium alloy was popular because of its high corrosive resistance, high specific strength and low specific gravity. It was also a bio-compatible material and non-magnetic”. Military Machine .com


“On it’s last flight ever, the SR-71 Blackbird set a speed record. It flew from Los Angeles to Washington, D.C. in 1 hour, 4 minutes, and 20 seconds. It averaged 2,124 miles per hour on this flight. Once it landed in D.C. it went straight into the Smithsonian. The SR-71 served as an unparalleled force multiplier with its advanced sensors and mission critical reconnaissance. Even with its short operational life span the SR-71 set the stage for the development of supersonic and hypersonic technology”. 

These SR-71 Facts were compiled by Military Machine

Boeing - Hyper sonic

It would cruise at 95,000 feet, at 3,800 miles per hour. The G-force feeling upon takeoff would last a full 12 minutes.jpg

“Building the future at Boeing requires looking decades ahead at what could be possible, and innovating now to make it happen. That’s the impetus behind Boeing’s first passenger-carrying hypersonic concept that was debuted at the American Institute of Aeronautics and Astronautics conference in Atlanta this week.

The passenger concept could have military or commercial applications; this is just one of several hypersonic vehicle concepts spanning a wide range of potential applications company engineers are studying. Engineers are working companywide to develop enabling technology will position the company for the time when customers and markets are ready to reap the benefits of hypersonic flight.

“We’re excited about the potential of hypersonic technology to connect the world faster than ever before,” said Kevin Bowcutt, senior technical fellow and chief scientist of hypersonics. “Boeing is building upon a foundation of six decades of work designing, developing and flying experimental hypersonic vehicles, which makes us the right company to lead the effort in bringing this technology to market in the future.” More here

The Rockwell X-30 concept


“The Rockwell X-30 was an advanced technology demonstrator project for the National Aero-Space Plane (NASP), part of a United States project to create a single-stage-to-orbit (SSTO) spacecraft and passenger spaceliner. It was cancelled in the early 1990s before a prototype was completed, although much development work in advanced materials and aerospace design was completed. While a goal of a future NASP was a passenger liner capable of two-hour flights from Washington to Tokyo, the X-30 was planned for a crew of two and oriented towards testing”. Wiki

NASA’s X-43


It's Official. X-43A Raises the Bar to Mach 9.6 
Guinness World Records recognized NASA's X-43A scramjet with a new world speed record for a jet-powered aircraft - Mach 9.6, or nearly 7,000 mph. The X-43A set the new mark and broke its own world record on its third and final flight on Nov. 16, 2004. 

In March 2004, the X-43A set the previous record of Mach 6.8 (nearly 5,000 mph). The fastest air-breathing, manned vehicle, the U.S. Air Force SR-71, achieved slightly more than Mach 3.2. The X-43A more than doubled, then tripled, the top speed of the jet-powered SR-71.  NASA

“The X-43 was an experimental unmanned hypersonic aircraft with multiple planned scale variations meant to test various aspects of hypersonic flight. It was part of the X-plane series and specifically of NASA's Hyper-X program. It set several airspeed records for jet aircraft. The X-43 is the fastest aircraft on record at approximately Mach 9.6.

 A winged booster rocket with the X-43 placed on top, called a "stack", was drop launched from a Boeing B-52 Stratofortress. After the booster rocket (a modified first stage of the Pegasus rocket) brought the stack to the target speed and altitude, it was discarded, and the X-43 flew free using its own engine, a scramjet.

The first plane in the series, the X-43A, was a single-use vehicle. Three of them were built. The first was destroyed after malfunctioning in flight; the other two flew successfully, with the scramjet operating for approximately 10 seconds, followed by a 10-minute glide and intentional crash into the ocean”. Wiki

X-51 Waverider

Below- The Boeing X-51 Waverider is an unmanned research scramjet experimental aircraft for hypersonic flight at Mach 5 (3,300 mph; 5,300 km/h) and an altitude of 70,000 feet (21,000 m). The aircraft was designated X-51 in 2005. It completed its first powered hypersonic flight on 26 May 2010. After two unsuccessful test flights, the X-51 completed a flight of over six minutes and reached speeds of over Mach 5 for 210 seconds on 1 May 2013 for the longest duration powered hypersonic flight. Wiki


Above- Waverider refers in general to aircraft that take advantage of compression lift produced by their own shock waves. The X-51 program was a cooperative effort by the United States Air Force, DARPA, NASA, Boeing, and Pratt & Whitney Rocketdyne. The program was managed by the Aerospace Systems Directorate within the U.S. Air Force Research Laboratory (AFRL). X-51 technology is proposed for use in the High Speed Strike Weapon (HSSW), a Mach 5+ missile which could enter service in the mid-2020s. Wiki



“The Paradoxical is a commercial supersonic/hypersonic passenger aircraft concept capable of flying on a sub-orbital parabolic trajectory between distant parts of the globe within hours. (view the video)

It uses a Rotary Ramjet engine as the air-breathing engine and then converts to a rocket to reach a suborbital altitude. A line of counterflowing jets of air on the aircraft’s leading edges reduces heat and drag during the ascent and re-entry phases of the flight.

The Paradoxal would thus be able to fly from Los Angeles to Sydney in less than 3 hours (7,585 miles) and make a gracious suborbital parabolic incursion into space for a fascinating view of the stars and earth from space.”

How It Works

The Paradoxal would to take off directly from any airfield using two Rim-Rotor Rotary Ramjet Engines (R4E). These turbines produce significant thrust in a single-stage by spinning ramjet thrusters at supersonic speeds (tip speeds up to Mach 3) held together by a carbon-fiber rim-rotor.

The R4E engines have a high power-to-weight ratio and could be manufactured at relatively low production costs (similar to today’s automotive turbochargers). Efficiencies are similar to piston engines and low pressure ratio gas turbines (20-30%).

The air-breathing engines would provide enough power to lift off, climb to 60,000 feet, and reach Mach 3. At this point, the engine would turn into a rocket engine by injecting liquid oxygen (LOX) into the gas exhaust port that would continue pushing the Paradoxal at supersonic speeds up to an altitude of 40 miles, setting it on a parabolic sub-orbital trajectory towards its distant destination.

In mid-flight, you would see earth’s curvature and the plane’s multiple onboard cameras would grant you access to video feed of the view along with the best pictures. You would even get to experience weightlessness for one brief minute before heading back towards earth.


The leading edge of the plane’s wings would be fitted with linear ‘Long Penetration Mode (LPM) nozzles’ so that air could flow out of them to create a ‘paradoxal’ effect whereby the plane could fly faster. As the speed increased to first supersonic, then hypersonic velocities, the engines or onboard tanks of compressed air would supply air to the LPM nozzles along the leading edges of the plane. As the Parodoxal accelerates and climbs, the LPM effect would reduce thermal loads while also reducing overall drag.

For this reason, the Parodoxal has a flying wing or blended wing body shape with one long leading edge. Passengers sit in one large, theatre-like cabin. Galleys, heads, and baggage stowage compartments are aft. Gone are the days of tube-and-wing planes with their long rows of cramped seats.

For the cruise part of the trajectory, the passenger plane would fly well above the stratosphere, at the very edge of black space. Hundreds of passengers would enjoy spectacular views of our planet. (A Large panoramic rooftop would definitely be a plus if it can be designed to endure the heat and stress).

About 45 minutes before landing, the LPM flow would be restarted using air from compressed air tanks. The LPM effect will cool the plane during atmospheric re-entry and allow it to slow gradually to subsonic velocity. By the time it returns to 50,000 feet in altitude, Parodoxal will again use air-breathing turbine engines and flying below Mach 1 for its final approach to its destination.

The plane’s wings and weight would allow it to land on a 6,000-foot runway.” Quote from Imaginactive / Paradoxal

Darpa Stuff