NASA Armstrong Fact Sheet: Bell X-2 Starbuster

The Bell X-2 was a rocket-powered, swept-wing research aircraft designed to investigate the structural effects of aerodynamic heating as well as stability and control effectiveness at high speeds and altitudes. The program was developed jointly in 1945 by Bell Aircraft Corporation, the U.S. Air Force and the National Advisory Committee for Aeronautics (NACA) to explore aerodynamic problems of supersonic flight and to expand the speed and altitude regimes obtained with the earlier X-1 series of research aircraft.

In 1946, the NACA Pilotless Aircraft Research Division (PARD) began testing rocket launched X-2 models at Wallops Island, VA, to gather stability and control data. Additional tests helped NACA and Bell engineers design a pilot escape system for the X-2. The NACA made its spin tunnel and supersonic wind-tunnels at the Langley Memorial Aeronautical Laboratory, Hampton, VA, available to evaluate various aspects of the X-2 design. The NACA was also responsible for scientific instrumentation of the X-2.

Two X-2 airframes, nicknamed "Starbuster," were built at Bell's plant in Wheatfield, NY, using stainless steel and K-monel (a copper-nickel alloy). The vehicles were designed to employ a two-chamber Curtiss-Wright XLR25 throttleable liquid-fueled rocket engine. It had a variable thrust rating from 2,500 to 15,000 pounds. The X-2 was equipped with an escape capsule for the pilot. In an emergency, the entire nose assembly would jettison and deploy a stabilizing parachute. Once at a safe altitude, the pilot would then manually open the canopy and bail out. Although the Air Force approved the final escape system design, NACA representatives were concerned that it might prove dangerous to use.

A Boeing B-50A bomber was modified to carry the X-2 to launch altitudes around 30,000 feet. The pilot then climbed into the X-2, dropped away from the bomber, and ignited the engines if it was a planned powered flight. After engine burnout, the pilot guided the X-2 to an unpowered landing on the surface of Rogers Dry Lake at Edwards Air Force Base, CA.

The X-2 (46-674) drops away from its Boeing B-50 mothership. Lt. Col. Frank "Pete" Everest piloted 674 on its first unpowered flight on 5 August 1954.

Because of a decision to install the first available engine in airframe 46-674, airframe 46-675 was delivered to Edwards first for glide tests. It arrived at Edwards on April 22, 1952. After two captive flights, Bell test pilot Jean L. "Skip" Ziegler made the first glide flight on June 27. A rough landing caused some damage to the aircraft and the second glide flight was delayed until Oct. 8. Two days later, Air Force test pilot Maj. Frank K. "Pete" Everest successfully completed the third glide flight of the X-2.

Following the unpowered tests, the X-2 was returned to Bell's plant in New York. The engine had not yet been installed in the first X-2, 46-674, so it was installed in the second shortly after it returned to Wheatfield. Captive flights with the new engine were carried out over Lake Ontario. During a flight to check the liquid oxygen system, an explosion resulted in the loss of the X-2 and severe damage to the B-50. Skip Ziegler and B-50 crew member Frank Wolko were both killed. The X-2 fell into Lake Ontario and was not recovered. The B-50A was damaged beyond economic repair and was subsequently replaced with a modified B-50D.

The following day, it began its journey to Edwards beneath the B-50D. The aircraft arrived on July 15 and technicians at the NACA High Speed Flight Station (HSFS) began to install instrumentation to gather handling qualities data. On the advice on the NACA, the Air Force purchased a Goodyear Electronic Digital Analyzer (GEDA) analog computer. Richard E. Day, NACA project engineer for the X-2, programmed the GEDA and turned it into a rudimentary flight simulator for the aircraft.

Read more:

https://www.nasa.gov/centers/armstrong/news/FactSheets/FS-079-DFRC.html

Here's more on the X-2. Looks like it was supposed to go to civilian NACA, which is the precursor to NSAA, but the Air Force never did it.

Just found it interesting that Q tagged the picture of the shuttle with X2.

X-2

E-2820

The Bell Aircraft Company X-2 (46-674) drops away from its Boeing B-50 mothership in this photo. Lt. Col. Frank "Pete" Everest piloted 674 on its first unpowered flight on 5 August 1954. He made the first rocket-powered flight on 18 November 1955. Everest made the first supersonic X-2 flight in 674 on 25 April 1956, achieving a speed of Mach 1.40. In July, he reached Mach 2.87, just short of the Mach 3 goal.

The other X-2, 675, was written off prior to making any powered flights. An explosion during a captive flight resulted in the death of Bell test pilot Jean "Skip" Ziegler. The X-2 was jettisoned over Lake Ontario, and the launch aircraft was damaged beyond repair. The first X-2, 674, continued flying, making a total of 17 launches. On 7 September 1956, Capt. Iven Kincheloe became the first man to exceed 100,000 feet when he reached an altitude of 126,200 feet in 674.

The X-2, initially an Air Force program, was scheduled to be transferred to the civilian National Advisory Committee for Aeronautics (NACA) for scientific research. The Air Force delayed turning the aircraft over to the NACA in the hope of attaining Mach 3 in the airplane. The service requested and received a two-month extension to qualify another Air Force test pilot, Capt. Miburn "Mel" Apt, in the X-2 and attempt to exceed Mach 3.

After several ground briefings in the simulator, Apt (with no previous rocket plane experience) made his flight on 27 September 1956. Apt raced away from the B-50 under full power, quickly outdistancing the F-100 chase planes. At high altitude, he nosed over, accelerating rapidly. The X-2 reached Mach 3.2 (2,094 mph) at 65,000 feet. Apt became the first man to fly more than three times the speed of sound.

Still above Mach 3, he began an abrupt turn back to Edwards. This maneuver proved fatal as the X-2 began a series of diverging rolls and tumbled out of control. Apt tried to regain control of the aircraft. Unable to do so, Apt separated the escape capsule. Too late, he attempted to bail out and was killed when the capsule impacted on the Edwards bombing range. The rest of the X-2 crashed five miles away.

1955-1956

NASA Photo / NASA photo

NASA orders a supersonic X-Plane, easy on the boom

Lockheed Martin will build the aircraft at its Skunk Works. The goal: the return of passenger travel at supersonic speed.

April 3, 2018 2:05 PM PDT

NASA wants to bring supersonic speed back to commercial aviation, and it's turning to Lockheed Martin to help us get there.

The space and aeronautics agency on Tuesday awarded Lockheed Martin a $247.5 million contract to build the Low-Boom Flight Demonstrator, a one-off X-Plane with a design intended to eliminate, or at least minimize, the sonic boom characteristic of supersonic aircraft breaking the sound barrier.

The experimental plane is intended to cruise at altitudes around 55,000 feet and to reach speeds around 940 miles per hour. The sound it generates, NASA says, should be at 75 perceived-level decibels, or "about as loud as a car door closing."

Eventually you might have some input into the experiment. After Lockheed Martin finishes its work, including flight tests, NASA expects to begin flying the demonstrator aircraft over unspecified US cities beginning in mid-2022, at which time it will collect data about "community responses" to the X-Plane's flights. It'll pass that information along to regulators in the US and abroad to help shape rules governing supersonic aircraft making flights over land.

Supersonic passenger flights were a thing for several decades. British Airways and Air France made regular flights across the Atlantic to the US until they retired their needle-nosed Concorde aircraft, which flew at about Mach 2 (twice the speed of sound), in 2003. Those transatlantic flights took just three and a half hours.

"It is super exciting to be back designing and flying X-planes at this scale," said Jaiwon Shin, NASA's associate administrator for aeronautics, in a statement.

Some private enterprises are also talking up a return of passenger aircraft that can hit supersonic speed. A company called Boom Supersonic has a target date of 2023 for when it hopes commercial service can begin again, and at last year's Paris Air Show said it has orders for 76 aircraft from five airlines.

Construction of NASA's latest X-Plane – the agency has a long history with those superfast, high-performance aircraft – will take place at the fabled Lockheed Martin Skunk Works in Palmdale, California. That's the hush-hush engineering facility that gave us high-wow-value aircraft including the U-2 and SR-71 spy planes.

If it all works out, NASA says, we could be looking ahead to new era of supersonic aircraft carrying passengers and cargo.