NF-104A | |
---|---|
Lockheed NF-104A, 56-0756, climbing with rocket power | |
Role | Aerospace trainer |
Manufacturer | Lockheed Aircraft Corporation |
Designer | Clarence "Kelly" Johnson |
First flight | 9 July 1963 |
Introduction | 1 October 1963 |
Retired | June 1971 |
Primary user | United States Air Force |
Number built | 3 |
Developed from | Lockheed F-104 Starfighter |
The Lockheed NF-104A is an American mixed-power, high-performance, supersonic aerospace trainer that served as a low-cost astronaut training vehicle for the North American X-15 and projected Boeing X-20 Dyna-Soar programs.
Three aircraft were modified from existing Lockheed F-104A Starfighter airframes, and served with the Aerospace Research Pilots School between 1963 and 1971, the modifications included a small supplementary rocket engine and a reaction control system for flight in the stratosphere. During the test program, the maximum altitude reached was more than 120,000 ft (36,600 m). One of the aircraft was destroyed in an accident while being flown by Chuck Yeager. The accident was depicted in the book The Right Stuff and the film of the same name. On December 10, 2019, Edwards Air Force Base released the complete video transcription of films of the 1963 flight and subsequent crash. [1]
With the advent of human spaceflight in the early 1960s, the United States Air Force (USAF) Experimental Flight Test Pilot's School at Edwards Air Force Base was renamed the Aerospace Research Pilots School (ARPS), with the emphasis on training moving away from the traditional test pilot course to a more spaceflight-oriented curriculum. [2]
A number of standard production F-104 Starfighters were obtained (including F-104D two-seat versions) [3] and used by the ARPS to simulate the low lift/high drag glide approach path profiles of the X-15 and the projected X-20 Dyna-Soar program. These maneuvers were commenced at 12,000 ft (3,700 m) where the F-104 engine was throttled back to 80% power; and with the flaps, speedbrakes and landing gear extended, the aircraft was established in a 30° dive with a pull-out for the landing flare starting at 1,500 feet (500 m) above the ground. These glide approaches gave little room for error.
It was realized that normal aircraft control surfaces had little or no effect in the thin air of the upper stratosphere and that any aircraft operating at extremely high altitudes would need to be equipped with a reaction control system (RCS). A modified version of the Bell X-1 was used for initial RCS tests, but was grounded after technical problems. It was replaced in 1959 with a NASA-modified Lockheed F-104A (55-2961), which carried RCS systems on its wing tips and in the fuselage nose. This aircraft (designated JF-104) achieved a maximum altitude of 83,000 feet (25,300 m) during the test program. Pilots who flew this aircraft included Neil Armstrong, who gained valuable experience in using the RCS. Pilots complained that the instrument displays were difficult to read and were not accurate enough for the critical zoom climb profiles required to reach high altitudes. [4]
Lockheed was awarded a contract by the United States Air Force to modify three F-104A aircraft for the dedicated role of aerospace trainer (AST) in 1962. The airframes were taken out of storage at AMARG and transported to the company factory for modification.
The F-104A design was already established as a lightweight, high-performance aircraft. For the AST project, emphasis was placed on removing unnecessary equipment, fitting a rocket engine to supplement the existing jet engine, fitting an onboard RCS, and improving the instrumentation. The following are the main differences between the production version and the AST:
The wingspan of the NF-104A was increased by the addition of wingtip extensions. This modification was needed to house the RCS roll control thrusters and decreased the wing loading.
The vertical fin and rudder were replaced by the larger area versions from the two-seat F-104 and were structurally modified to allow installation of the rocket engine.
The fiberglass nose radome was replaced with an aluminum skin and housed the pitch and yaw RCS thrusters.
The air intakes originally designed by Ben Rich were of the same fixed geometry as the F-104A, but included extensions to the inlet cones for optimum jet engine operation at higher Mach numbers. Internal fuselage differences included provision for rocket propellant oxidizer tanks, removal of the M61 Vulcan cannon, radar equipment and unnecessary avionics. A nitrogen tank was installed for cabin pressurization purposes. This was required, as there would be no bleed air available from the engine after its normal and expected cutoff in the climb phase.
In addition to the standard General Electric J79 jet engine, a Rocketdyne AR2-3 rocket engine was fitted at the base of the vertical fin. This engine burned a mixture of JP-4 jet fuel and 90% hydrogen peroxide oxidizer solution. The NF-104 carried enough oxidizer for approximately 100 seconds of rocket engine operation. The thrust level could be adjusted to maximum or approximately half power by the pilot using an additional throttle lever on the left side of the cockpit.
The reaction control system consisted of eight pitch/yaw thrusters (four for each axis) and four roll thrusters. They used the same kind of hydrogen peroxide fuel as the main rocket engine from a dedicated 155 lb (70 kg) fuel tank and were controlled by the pilot using a handle mounted in the instrument panel. The pitch/yaw thrusters were rated at 113 lbf (500 N) thrust each and the roll thrusters were rated at 43 lbf (190 N) thrust.
The NF-104A was able to reach great altitudes through a combination of zoom climbing (building up a high speed in a shallow dive at high altitude, and then climbing steeply, converting speed and momentum into altitude) and use of the rocket engine (to reach higher level speeds and to maintain climb rate for as long as possible after entering the zoom climb). A typical mission involved a level acceleration at 35,000 feet (10,700 m) to Mach 1.9 where the rocket engine would be ignited, and on reaching Mach 2.1 the aircraft would be pitched up to a climb angle of 50-70° by carefully applying a load equal to 3.5 g. The J79 afterburner would start to be throttled down at approximately 70,000 feet (21,300 m) followed shortly after by manual fuel cutoff of the main jet engine itself around 85,000 feet (25,900 m) to prevent fast-rising engine temperatures from damaging the turbine stages of the jet engine. After continuing over the top of its ballistic arc, the NF-104 would descend back into denser air where the main engine could be restarted using the windmill restart technique for recovery to a landing. [5]
The first NF-104A (USAF 56-0756) was accepted by the USAF on 1 October 1963. It quickly established a new unofficial altitude record of 118,860 feet (36,230 m) and surpassed this on 6 December 1963 by achieving an altitude of 120,800 feet (36,800 m). The aircraft was damaged in flight June 1963 when a rocket oxidizer vessel exploded. It suffered an inflight rocket motor explosion in June 1971. Although the pilot was able to land safely, the damaged aircraft was retired and this marked the end of the NF-104 project. This aircraft was transferred to the National Museum of the United States Air Force. It is on display at Nevada County Air Park, Grass Valley, California. wearing the markings of "56-0751".
The second NF-104A (USAF 56-0760) was accepted by the USAF on 26 October 1963. After retirement, this aircraft was mounted on a pole outside the U.S. Air Force Test Pilot School at Edwards Air Force Base and can still be seen there today. The extended wingtips, RCS, metal nose cone, and other parts from 56-0760 were loaned to Darryl Greenamyer for his civilian aviation record attempts using a highly modified F-104. When he was forced to eject during a record flight, his aircraft was destroyed and the parts were never returned. [6]
The third NF-104A (USAF 56-0762) was delivered to the USAF on 1 November 1963, and was destroyed in a crash while being piloted by Chuck Yeager on 10 December 1963. This accident was depicted in the book Yeager: An Autobiography , and the book and film adaptation of The Right Stuff. The aircraft used for filming was a standard F-104G flying with its wingtip fuel tanks removed, but otherwise lacked any of the NF-104A's modifications, most visibly the angled-up rocket engine at the base of the vertical stabilizer. [7]
Data fromLibis. [8]
General characteristics
Performance
Related development
Aircraft of comparable role, configuration, and era
Related lists
The Lockheed F-104 Starfighter is an American single-engine, supersonic interceptor which was extensively deployed as a fighter-bomber during the Cold War. Created as a day fighter by Lockheed as one of the "Century Series" of fighter aircraft for the United States Air Force (USAF), it was developed into an all-weather multirole aircraft in the early 1960s and produced by several other nations, seeing widespread service outside the United States.
The Northrop T-38 Talon is a two-seat, twinjet supersonic jet trainer designed and produced by the American aircraft manufacturer Northrop Corporation. It was the world's first supersonic trainer as well as the most produced.
The Douglas X-3 Stiletto is a 1950s United States experimental jet aircraft with a slender fuselage and a long tapered nose, manufactured by the Douglas Aircraft Company. Its primary mission was to investigate the design features of an aircraft suitable for sustained supersonic speeds, which included the first use of titanium in major airframe components. Douglas designed the X-3 with the goal of a maximum speed of approximately 2,000 mph (3,200 km/h), but it was seriously underpowered for this purpose and could not even exceed Mach 1 in level flight. Although the research aircraft was a disappointment, Lockheed designers used data from the X-3 tests for the Lockheed F-104 Starfighter which used a similar trapezoidal wing design in a successful Mach 2 fighter.
Joseph Albert Walker was an American World War II pilot, experimental physicist, NASA test pilot, and astronaut who was the first person to fly an airplane to space. He was one of twelve pilots who flew the North American X-15, an experimental spaceplane jointly operated by the Air Force and NASA.
The Republic XF-103 was an American project to develop a powerful missile-armed interceptor aircraft capable of destroying Soviet bombers while flying at speeds as high as Mach 3. Despite a prolonged development, it never progressed past the mockup stage.
The Convair XF-92 was an American, delta wing, first-generation jet prototype. Originally conceived as a point-defence interceptor, the design was later used purely for experimental purposes and only one was built. However, it led Convair to use the delta-wing on a number of designs, including the F-102 Delta Dagger, F-106 Delta Dart, B-58 Hustler, the US Navy's F2Y Sea Dart as well as the VTOL FY Pogo.
The General Electric J79 is an axial-flow turbojet engine built for use in a variety of fighter and bomber aircraft and a supersonic cruise missile. The J79 was produced by General Electric Aircraft Engines in the United States, and under license by several other companies worldwide. Among its major uses was the Lockheed F-104 Starfighter, Convair B-58 Hustler, McDonnell Douglas F-4 Phantom II, North American A-5 Vigilante and IAI Kfir.
The Lockheed CL-1200 Lancer was a late 1960s company-funded proposal for a fighter aircraft based on the Lockheed F-104 Starfighter. The CL-1200 was conceived and marketed mainly for and to non-US military services, as an export product. As such it would have competed with combat-proven designs like the Dassault Mirage III, McDonnell Douglas F-4 Phantom II, Mikoyan-Gurevich MiG-21, and Northrop F-5E Tiger II. The CL-1200 competed unsuccessfully against proposed fourth generation designs, under the US government's Lightweight Fighter program, which would eventually result in the General Dynamics F-16 and Northrop F-17 Cobra.
The Canadair CF-104 Starfighter is a modified version of the Lockheed F-104 Starfighter supersonic fighter aircraft built in Canada by Canadair under licence. It was primarily used as a ground attack aircraft, despite being designed as an interceptor. It served with the Royal Canadian Air Force (RCAF) and later the Canadian Armed Forces (CAF) until it was replaced by the McDonnell Douglas CF-18 Hornet in 1987.
The Aeritalia F-104S Starfighter was a licensed production Italian version of the Lockheed F-104 Starfighter, which served in the Italian Air Force, and was its mainstay from the late 1960s until the beginning of the 21st century. The F-104S also served in the Turkish Air Force until the mid-1990s. The F-104S was the final development of the Starfighter line.
The Lockheed XF-104 Starfighter was a single-engine, high-performance, supersonic interceptor prototype for a United States Air Force (USAF) series of lightweight and simple fighters. Only two aircraft were built; one aircraft was used primarily for aerodynamic research and the other served as an armament testbed, both aircraft being destroyed in accidents during testing. The XF-104s were forerunners of over 2,500 production Lockheed F-104 Starfighters.
A zoom climb or an unrestricted climb is a maneuver in which the rate of climb is greater than the maximum climb rate using only the thrust of the aircraft's engines. The additional climb rate is attained by reduction of horizontal speed. Before a zoom climb, the aircraft accelerates to a high air speed at an altitude at which it can operate in sustained level flight. The pilot then pulls steeply upward, trading the kinetic energy of forward motion for altitude. This is different from a steady climb, where the increase in potential energy comes from mechanical work done by the engines.
The General Dynamics X-62 VISTA is an experimental aircraft, derived from the F-16D Fighting Falcon, which was modified as a joint venture between General Dynamics and Calspan for use by the United States Air Force (USAF). Originally designated NF-16D, the aircraft was redesignated X-62A in June 2021 as part of an upgrade to a Skyborg, with System for Autonomous Control of Simulation (SACS).
The General Electric YJ93 turbojet engine was designed as the powerplant for both the North American XB-70 Valkyrie bomber and the North American XF-108 Rapier interceptor. The YJ93 was a single-shaft axial-flow turbojet with a variable-stator compressor and a fully variable convergent/divergent exhaust nozzle. The maximum sea-level thrust was 28,800 lbf (128 kN).
The Grumman F11F-1F Super Tiger is a single-seat fighter aircraft originally developed for the United States Navy (USN). Based on the USN's F-11 Tiger, the F11F-1F did not proceed beyond the two F11F-1F prototypes.
The Red Baron was a highly modified Lockheed F-104 Starfighter which set a FAI Class C-1 Group III 3 km speed record of 1,590.45 kilometres per hour (988.26 mph), in 1977 which still stands. It was assembled by Darryl Greenamyer and sponsored by Ed Browning and the Red Baron Flying Service of Idaho Falls, Idaho. The aircraft was destroyed in an accident in 1978.
The Northrop N-102 Fang was a fighter aircraft design created by Northrop Corporation and proposed to the United States Air Force in 1953. The Fang was explicitly designed as a ”light” or “lightweight fighter” in direct response to what Northrop saw as the ever-increasing weight, size, complexity, and cost of Western fighter designs. While the Fang was ultimately overlooked in-favor of the Lockheed F-104 Starfighter, Northrop’s interest in the lightweight fighter concept would ultimately come to fruition with the F-5 Freedom Fighter, itself spawning a moderately successful fighter family.
Neil Burgess Jr. was a leading American aircraft propulsion engineer and designer. Working at General Electric with Gerhard Neumann, they won the 1958 Collier Trophy for their work on the General Electric J79 turbojet engine which powered the Lockheed F-104 Starfighter.