XNJ140E part 1

Dec 252012

The General Electric XNJ140E nuclear turbojet was proposed in March 1960 to meet then-current DoD guidelines for the nuclear aircraft program. It utilized a single X211 turbojet mated to a beryllium oxide reactor, a change from the prior XMA-1 engine standard which had one reactor powering two X211 turbojets. Ground test for the XNJ140E was scheduled for December 1962, with flight testing to begin in a Convair NX-2 in 1965.

The XNJ140E was designed for a lifespan of 1000 hours under power, at which point it was to be removed from the aircraft and overhauled. The XNJ140E-1 was to be the developmental model, and would have had an estimated dry weight of 60,600 pounds. Of that, 18,320 pounds were turbojet, while 42,230 pounds were reactor, shield and controls.

The reactor assembly was 33 inches long and 62 inches in diameter, formed from 25,000 hexagonal tubes made from yttria-stabilized beyllia containing uranium. Peak operating temperature was to be 2530 degrees F. The reactor was capable of at least 121 megawatts for a nuclear-only runway takeoff, providing 35,310 pounds of thrust at Mach 0 and at sea level. For cruise at 35,000 feet and Mach 0.8, 50.5 megawatts would provide 8,120 pounds of thrust.

Nuclear Powered Snark

bomber, nukes 1 Response »

Dec 242012

Not much info on this as yet. An early 1958 General Electric study to provide the Snark intercontinental cruise missile with a nuclear turbojet to give the craft 200 hours of Mach 0.9 performance at 30,000 feet. As the Snark had only a single warhead, it’s not at all clear what this performance was hoped to accomplish.

Aviation Archeology

bomber, fighter, nukes, Recon, research No Responses »

Dec 212012

“Code One” is the in-house magazine put out by Lockheed-Fort Worth. They have been adding a lot of good stuff regarding projects to their website over the years, and now have a page devoted specifically to diagrams of unbuilt aircraft:

Aviation Archeology

Only a few just now, but they say that there are a lot more coming.

B-52G Nuclear Turbojet Testbed

bomber, nukes, research No Responses »

Dec 142012

Previously shown but not understood HERE, in 1961 GE proposed modifying a B-52G to serve as a testbed for a single XNJ140E-1 nuclear turbojet. The very large engine would be contained in a nacelle attached to the port rear fuselage. With eight conventional J57 chemical turbojets, the testbed aircraft would be capable of putting the engine through the altitude and airspeed paces that would be expected of it in the NX-2 nuclear powered bomber demonstrator (35,000 feet and Mach 0.8). This configuration would be capable of sustained nuclear flight.

Another configuration would have a second XNJ140E-1 nuclear turbojet on the other side of the fuselage, and only four J57’s. This aircraft would be capable of pure nuclear flight from takeoff to landing, with the J57’s as emergency backup.

Approximate isodose lines around the nuclear B-52G in powered flight

Early B-52

bomber 1 Response »

Oct 302012

Standard Aircraft Characteristics sheets describing the Boeing XB-52 as of December 1949. This was not the B-52 as it was actually built… a number of design changes were yet to come. Most notable is that the wing is much closer to the nose. The cockpit in fact extends aft beyond the leading edge of the wing root.

SAC sheets used to be produced in large numbers to describe in concise form not only the aircraft the USAF was flying, but aircraft it was hoping to fly. These sheets would be produced by the USAF or by the contractors; contractors would often produce SACs describing conceptual or preliminary designs. There does not seem to have been a central clearinghouse for them… they were produced and distributed with no readily apparent rhyme or reason.

1970’s Teledyne Ryan Stealthy RPV

bomber, research, stealth 2 Responses »

Oct 132012

A 1974 design by Teledyne Ryan for a stealthy remotely piloted vehicle While the general shape is certainly well within the norm for stealthy craft, the structure itself is quite different: it is basically a metal vehicle optimized for stealth, wrapped in a radar-transparent plastic skin optimized for aerodynamics. The only aspect of it that really seems to fail modern stealthy practices is the apparent straight shot in to the turbine face. From the Jay Miller collection.

The technology behind this was patented by Teledyne Ryan:

Aircraft of low observability

CORRECTION: This was originally posted as a TRW design, when in fact it was a Teledyne Ryan design. D’oh.

SCAMP 3-view

bomber 1 Response »

Sep 242012

From a February 1980 report, layout drawings of the SCAMP as then envisioned. Most obvious difference from the F-16XL is the vertical tail… instead of the F-16 tail, it utilized the base of the F-16 tail with an all-movable vertical stabilizer… which was previously a horizontal stabilizer.

SCAMP

bomber, fighter 2 Responses »

Sep 202012

The design for what became the F-16XL began in 1977 as the Supersonic Cruise and Maneuver Prototype at General Dynamics-Fort Worth. The idea was to incorporate lessons learned in SST design into military aircraft. The SCAMP was to be a highly modified F-16 with a 56-inch fuselage stretch, an all-new cranked-delta wing, and an all-new vertical tail, along with many smaller changes. The use of computers – already new with the baseline F-16 – would allow the aircraft to be flown… otherwise unlikely, due to the relaxed static stability of the design (i.e. left to it’s own the design would oscillate in attitude and angle of attack until it went truly unstable). The SCAMP would be capable of carrying a much greater payload than the F-16, such as a sizable bombload.

The F-16XL as actually built used an F-16 vertical tail. But this earlier SCAMP design, from a February 1980 report, used a new all-moving vertical tail. Even earlier designs used all-moving wingtips, which were themselves the horizontal stabilizers from a regular F-16. While that idea undoubtedly had merit, it would not allow for missiles to be carried on the wingtips, and thus fixed wingtips were designed in.

Supersonic Flying Wing

bomber, future projects, jetliner, transports No Responses »

Aug 302012

NASA has just signed a small ($100 K) study contract for a “ninja star” shaped jetliner. It would be a pointy cruciform in plan view; at low speed the longer axis would be the wing and at high speed the shorter axis would be the wing. To accomplish this, the jet engines would need to rotate 90 degrees.

Supersonic Flying Wing Nabs $100,000 from NASA

This is not an entirely new idea. In the 1970’s Boeing studied a similar concept… supersonic aircraft with single-pivot rotating wings that would present long wings for low speed and short wing for high speed.

And it goes back even further. in 1963, former German aircraft designer Richard Vogt filed a patent via Boeing for a “TWO POSITION VARIABLE SHAPED WING” based on the same idea. The patent drawings seem to show a supersonic transport.

B-58 Mockup Photo

bomber, nukes No Responses »

Aug 242012

Following on the heels of the MX-1964 mockup was a mockup of the B-58 as it more or less was built. Clearly built in the same facility, what’s unclear from the photo is whether any components from the previous mockup were re-used. All the major components appear to be substantially altered, so it might have been an all-new structure, or it might have used some of the same internal supports. It would be nice if such things were able to be preserved, but mockups like this usually wind up getting turned into firewood.

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