Although the Lockheed F-117A stealth fighter is almost
certainly NOT in the original fighter sequence of designations, the end of
this particular sequence is perhaps most apt for a discussion of this unusual
warplane, most of the details of which are still highly classified.
The F-117A number was designated in sequence with other aircraft operating at Groom. These included the Red Squadron - a squadron of Soviet aircraft that the US government had "acquired". These flights where logged in the pilot's logs as YF-110, YF-113, YF-114, etc. The pilots of the Senior Trend aircraft logged in the next in sequence, the YF-117A for a lack of an unclassified designator. When Lockheed printed up the Dash 1 flight manuals, they printed F-117A on the front cover.
The F-117A was the first warplane to be specifically designed from the outset for low radar observability. The Lockheed Advanced Development Company (better known as the "Skunk Works" began working on Stealth as far back as the late 1950s, and low radar observability had played a role in the design of the A-12/YF-12/SR-71 series of Mach 3+ aircraft. During 1975, Skunk Works engineers began working on an aircraft which would have a greatly reduced radar cross section that would make it all but invisible to enemy radar, but would nevertheless still be able to fly and carry out its combat mission.
The technique they came up with was known as faceting, in which the ordinarily smooth surface of the airframe is broken up into a series of trapezoidal or triangular flat surfaces arranged in such a way that the vast majority of the radar incident on the air craft from a source will be scattered away from the aircraft at odd angles, leaving very little to be reflected directly back into the receiver. An additional reduction in radar cross section was to be obtained by covering the entire surface of the aircraft with radar absorbent material (RAM). One of the disadvantages involved in the use of faceting on aerodynamic surfaces was that it tended to produce an inherently unstable aircraft in all three axes --- pitch, roll, and yaw.
In 1969 Lockheed engineers showed up at the EG&G RCS facility at Groom Lake with a very crude prototype model of the first stealth plane, the Have Blue. Special Projects team members T.D. Barnes, Cowen Dawson, and Bobby Luker had the distinction of mounting the prototype on the pylon for its first RCS evaluation. Barnes reports the prototype showing up like a barn on the radar screens and script charts when the radar array beamed on the prototype. Lockheed, "the Customer" departed with the data and returned a couple months later with the modified prototype. Once again the Special Projects team conducted a RCS evaluation of the plane on the pylon. This time the radar return was much smaller. This sequence of painting the prototype with radar beams and recording the return continued until a bird landing on the prototype produced a greater return than the plane. Eventually it was the pylon pole producing too much ground clutter so a pylon was constructed from a block of Styrofoam. By the end of the RCS evaluations and Lockheed modifications it was necessary to mark the prototype with a medal tag to identify it on the script charts and readouts. In early 1977, Lockheed received a contract from the Defense Advanced Research Projects Agency (DARPA) for the construction of two
60-percent scale flyable Test aircraft under a project named Have Blue. The
name Have Blue seems to have no specific meaning, probably having been chosen
at random from an approved list of secret project names. Shortly after the
Have Blue contract was let, the project was transferred over to Air Force
System Command control and became highly "black," with all information
about it being highly classified and restricted to those with a need to know.
Outside of a few people at Lockheed and the Defense Department, no one knew
Have Blue even existed.
The two Have Blue aircraft were built at Lockheed in only a few months. The first example was intended to evaluate the type's flying characteristics, whereas the second was to evaluate the radar signature. In order to save sometime and some money, existing off-the-shelf components were used where feasible.
The engines were a pair of standard production non-afterburning General Electric J85s, mounted in enclosures sitting atop the wings. The main landing gear was taken from a Fairchild Republic A-10, and fly-by-wire components were scavenged from an F-16. The instrumentation and the ejector seat were taken from a Northrop F-5.
The Have Blue aircraft had the same general shape as that which would later become familiar with the F-117A, except that the twin rudders were located forward of the exhaust ejectors and were angled inward rather than outward. The inward cant was about 30 degrees. The leading edge of the semi-delta wing was swept back at 72.5 degrees. The wing featured two inboard trailing edge elevons for pitch and roll control. Four spoilers (two on top of the wing and two on the bottom) were mounted just forward of the elevons. There were no flaps or speed brakes. The wing trailing edge was less deeply notched than that of the F-117A. A single cockpit with an ejector seat was provided.
The Have Blue aircraft employed V-type windshields (similar to those of the F-102/F-106). No weapons bay nor any sort of tactical equipment at all was fitted. The Have Blue aircraft were equipped with fly-by-wire (FBW) flight controls adapted from the F-16 system. However, the system had to be modified to handle an aircraft that was unstable about all three axes (the F-16 is unstable only about the pitch axis).
The problem of designing a stealthy system for airspeed measurement had not yet been solved, and the aircraft were equipped with a conventional pitot tube which was retracted during testing for radar reflections. The inertial navigation system provided enough speed data for test purposes when the probe was retracted.
Two prototypes were built at a cost of $37 million for both aircraft. Lockheed workers assembled the two Have Blue aircraft in a cordoned-off area in Lockheed's Plant 10 facility housed at the USAF Plant 42 in Palmdale, California. Neither aircraft ever received an official DoD designation, or did they get a USAF serial number. However, Lockheed did give the aircraft its own manufacturer's serial numbers ---1001 and 1002, meaning Plant 10, aircraft numbers 1 and 2.
The first example (1001) was finished in November of 1977. In order to keep the project away from prying eyes, the Have Blue prototype was shipped out to the Groom Lake Test Facility in Nevada in high secrecy for the test flights. Groom Lake is located in a particularly remote area of the Nellis test range complex, and is a good location for the testing of secret aircraft. A camouflage paint scheme was applied to make it hard for unwanted observers at Groom Lake to determine the aircraft's shape.
The first flight of the Have Blue took place in January or February of 1978 (the exact date is still classified), veteran Lockheed test pilot William M. Bill Park being at the controls. At an early stage, Bill Park was assisted in the flight test program by Lt. Col. Norman Kenneth (Ken) Dyson of the USAF. Flight test of the Have Blue initially went fairly smoothly, and the fly-by-wire system functioned well. The landing speed was quite high (160 knots), as expected because of the lack of flaps or speed brakes. However, on May 4, 1978, Have Blue prototype number 1001 was landing after a routine test flight when it hit the ground excessively hard, jamming the right main landing gear in a semi-retracted position. Pilot Bill Park pulled the aircraft back into the air, and repeatedly tried to shake the gear back down again. After his third attempt failed, he was ordered to take the aircraft up to10,000 feet and eject. Park ejected successfully, but he hit his head and was knocked unconscious. Since he was unable to control his parachute during descent or landing, his back was severely injured on impact. He survived, but was forced to retire from flying. The Have Blue aircraft was destroyed in the crash, and the wreckage secretly buried somewhere on the Nellis test range complex.
Have Blue 1002 arrived at Groom Lake shortly after the loss of number 1. It took to the air for the first time in June of 1978, Lt. Col. Ken Dyson being at the controls. From mid-1978 until early 1979, Lt. Col. Dyson flew more than 65 test sorties, testing the response of the aircraft to various types of radar threats.
The Have Blue prototype 1002 proved to be essentially undetectable by all airborne radars except the Boeing E-3 AWACS, which could only acquire the aircraft at short ranges. Most ground-based missile tracking radars could detect the Have Blue only after it was well inside the minimum range for the surface-to-air missiles with which they were associated. Neither ground-based radars nor air-to-air missile guidance radars could lock onto the aircraft.
It was found that the best tactic to avoid radar detection was to approach the radar site head on, presenting the Have Blue's small nose-on signature. The application of the RAM was rather tricky, and ground crews had to be careful to seal all joints thoroughly before each flight.
RAM came in linoleum-like sheets which were cut to shape and bonded to the skin to cover large areas. Doors and access panels had to be carefully checked and adjusted for a tight fit between flights and all gaps had to be filled in with conductive tape and then covered over with RAM. Paint-type RAM was available, but it had to be built up by hand, coat by coat. Even the gaps around the canopy and the fuel-filler door had to be filled with paint-type RAM before each flight. Ground crews had to even make sure that all surface screws were completely tight, since even one loose screw for an access panel could make the aircraft extremely visible during radar signature tests.
Have Blue number 1002 was lost in July of 1979. During its 52nd flight, with Lt. Col. Dyson at the controls, one of its J85 engines caught fire. The subsequent intense fire burned through the hydraulic fluid lines, forcing Lt. Col. Dyson was to eject. Have Blue #1002 was a total loss, and consequently, also secretly buried on the Nellis test range complex. No further Have Blue aircraft were built since the general concept had been proven.
The F-117 is NOT a fighter jet. Because it is small and cute, everyone wanted to call it a fighter, and even gave it an "F" (fighter) designation. IT HAS NO AIR TO AIR COMBAT CAPABILITIES, AND DOES NOT CARRY MISSILES. IT DROPS BOMBS, THEREFORE IT IS A BOMBER!!
The F-117A stealth bomber had the same general
configuration of the Have Blue test aircraft, but was much larger and heavier
and was provided with an offensive military capability. The structure of the
F-117A is constructed mainly of aluminum, with some titanium being used in the
engine and in the exhaust systems. The main facets of the outer skin are
separately fastened to a rather complex skeletal frame. Since the accurate
shaping and placement of these facets is critical to achieving a low radar
cross section (RCS), production tooling had to be ten times more precise than
the tooling used to build conventional aircraft.
The entire outer skin of the F-117A is covered by radar absorption material (RAM). The exact composition of the RAM is classified, but it is believed to consist of a matrix of magnetic iron particles held in place by a polymer binder. Originally, RAM came in large flexible sheets, and was bonded to a metal wire mesh, which was in turn glued to the airframe of the F-117A. Later, when the aircraft entered service, the Air Force built a special facility for the application of the RAM. In order to provide for uniform and accurate application, as well as to prevent people from coming into contact with the highly toxic solvents which make the RAM liquid, the process is completely automated.
During the application of the RAM, the F-117A is supported spit-like and slowly turned as the RAM is sprayed on by computer-controlled nozzles. Minor touch-up s are made in the field using a hand-held spray gun.
The engines powering the F-117A are a pair of non-afterburning General Electric F404-GE-F1D2 turbofans, derivatives of the afterburning F404-GE-400 turbofans that power the McDonnell Douglas F/A-18 Hornet. They are housed in broad nacelles attached to the sides of the angular fuselage. The General Electric turbofans are fed by a pair of air intakes (one on each side of the fuselage). Two gratings with rectangular openings cover each intake.
The purpose of these gratings is to prevent radar waves from traveling down the intake ducts and reaching the whirling blades of the turbofans, which would tend to produce large echoes. This works because the spacings between the grids on the grating are smaller than the wavelengths of most radars. The grating is covered with RAM, which helps reduce the reflections even further.
The small fraction of incident radar energy which does pass through the grating is absorbed by RAM mounted inside the duct. Unfortunately, these gratings also restrict airflow to the engines, so a Large blow-in door is fitted atop each engine nacelle to increase airflow to the engine during taxiing, takeoffs, or low-speed flight. Ice buildup on the intake gratings is a persistent problem, which tends to clog the rectangular openings and restricts the airflow even further. In order to clear the ice, the F-117employs a electrical heating system to remove ice during flight. A light on either side of the fuselage illuminates the intake covers, enabling the pilot to watch the deicing operation during night flights.
One of the more unusual aspects of the F-117 is its engine exhaust system. Like the air inlets, the exhaust outlets are mounted atop the wing chord plane, one on each side of the centerline. The engine exhausts are narrow and wide and are designed to present as low an infrared signature as possible and mask the rear of the engine from radar illumination from the back. The exhaust ducts are round at the rear of the turbofans, but are flattened out and become flume-like by the time that they reach the front of the narrow slotted exhaust outlets at the rear of the fuselage. At the end of each of the narrow slotted exhaust ducts, there are twelve grated openings, each being about six inches square. These grated openings help reduce unwanted radar reflection from the rear as well as providing additional structural strength to the exhaust ducts. The exhaust gratings are shielded from the rear and from the bottom by the F-117's platypus-bill-shaped rear fuselage section.
The extreme rear edge of the aircraft behind the exhaust slot is covered with heat-reflecting tiles. These ceramic tiles help to keep the rear of the aircraft cool, since they tend to reflect the infrared radiation emitted from the exhaust, rather than absorbing it as metals tend to do. The bypass air from the engine is also used to help cool down the entire metal structure of the rear of the aircraft.
The exhaust system is complex, incorporating sliding elements and quartz tiles to accommodate heat expansion without changing shape. Although the system works fairly well, Lockheed has reported that the design of this exhaust system was the single most difficult item in the entire F-117A project.
A typical fighter has a head-on RCS of about five square meters, which is technical language for saying that it seems as large on radar as a perfectly-reflective sphere of the same cross-sectional area. However, if critical flat surfaces or whirling turbine blades happen to be exposed to the radar, the RCS can be much larger. Reportedly, the combination of faceting and the application of RAM gives theF-117A an effective radar cross section of somewhere between 0.01 and 0.001 square meters, which makes the F-117A appear to be no larger than a small bird on a radar screen. This means that a typical radar will not be able to detect an F-117A at a range any greater than 8-16 miles.
Directional stability and control of the F-117A is provided by a pair of all-flying tails mounted on the aircraft's central spine and oriented in a V arrangement, reminiscent of the tail of the Beechcraft Bonanza. Unlike most V-tails, however, they have no pitch-control function. Each vertical tail consists of a fixed stub, and an all-flying rudder which pivots around a fixed shaft. The hinge line between stub and moveable tail is Z-shaped rather than straight, in accord with the stealth principle of the avoidance of any straight edges.
Both the fixed stub and the all-flying rudder are faceted to further reduce radar reflectivity. On the Have Blue test aircraft, the vertical tails were mounted further outboard on the wings and were canted inward rather than outward. The purpose of the inward-canted vertical tails on the Have Blue was to shield the upward-facing platypus exhaust nozzles from infrared detectors above the aircraft. In practice, however, these tails tended to act as reflectors for infrared radiation, bouncing the rays toward the ground and making the aircraft more visible from below.
Originally, the basic stealth design philosophy was to have the lowest observability from the bottom and from the front, with the upper hemisphere having less stringent requirements. Consequently, on the F-117A aircraft, the tails were moved back further on the fuselage so that they are no longer directly over the exhaust. In addition, the Have Blue tails were in effect mounted on twin booms which was a structurally inefficient arrangement.
The leading edge wing sweep on the Have Blue was 72.5 degrees, and the resulting low aspect ratio gave a rather poor payload-range performance. To improve the performance, the wing sweep was reduced to 67.5 degrees on the F-117A.The flying surfaces on the F-117A consist of four elevons on the wing trailing edge (two inboard and two outboard) and two all-flying rudders mounted in a V arrangement on the rear fuselage. The elevons and the rudder are all faceted to reduce their radar signature, and the hinge lines between the wings and the elevons sealed with flexible RAM. The four elevons can deflect upward or downward by 60 degrees, and the rudders can deflect 30 degrees left or right. The elevons act in the pitch and roll axes, where as the rudders act in the yaw axis. The angle of attack during landing is about 9 degrees. The elevons do not double as flaps, which makes the landing speed of the F-117A rather high.
The Have Blue cockpit canopy windshield had a center bow, reminiscent of that of the F-102/F-106 interceptor. The F-117A replaced this windshield with a center flat panel since a heads-up display would not work very well with a center bow blocking the view. This resulted in a change in the shape of the nose to a steep downward-sloping section for good downward visibility with a sharp, pyramidal-shaped nose cap for aerodynamics and stealth. This change made the F-117 slightly more observable by radar than the Have Blue.
The cockpit of the F-117is covered by a large and heavy hood-like canopy with five separate flat transparencies (one on either side and three in front). The visibility from the cockpit is rather limited upward, downward, and to the rear. The canopy opens to the rear and has serrated edges in order to limit the radar reflectivity of the joint between canopy and fuselage when the canopy is closed. The five flat transparent panels are specially treated to further reduce the aircraft's RCS. The windshield is coated with a special gold film layer to prevent the pilot's helmet from being detected by radar. This was found to be an important problem during early tests.
The pilot sits on a McDonnell Douglas ACES II ejector seat, the same type of seat fitted to the F-15C/D. The cockpit is equipped with a Heads-Up Display (HUD). The main control panel has two five inch CRTs, while the main FLIR/DLIRCRT had a twelve-inch screen. For nighttime operations in clear weather at low altitudes, the aircraft is primarily flow by using the FLIR/DLIR CRT. The F-117A, like the Have Blue before it, is unstable about all three axes and requires a fly-by-wire system in order to be able to fly at all. The fly-by-wire system is similar to that in the F-16, and is quadruply redundant. There are four independent channels which each control the same function. The signals from each of the channels are constantly being compared with each other, and if one signal is found to differ from the other three, its channel is assumed to have failed and is automatically shutdown. In the unlikely event that all four channels manage to fail at the same time, the aircraft cannot be flown and the pilot would be forced to eject.
Since the aircraft cannot use any sort of radar navigation system, the fly-by-wire system relies on information about airspeed and angle of attack from four individual static pitot probes of diamond section with pyramid-like tips mounted in the extreme nose. Each of the four-sided pitot heads have tiny holes on each facet, and differential readings from each hole provide air speed, pitch and yaw information to the flight control system. The design of these four nose sensors, plus the requirement that they not produce any unwanted radar reflections, was one of the more difficult engineering problems the Lockheed team had to solve.
The F-117A also differed from the Have Blue in having a weapons bay. Since external hard points for bombs or fuel tanks are taboo for a stealth attack aircraft, all stores must be carried internally. The weapons bay is located in the belly on the centerline. It has two wells, each covered by an inboard-opening door. The outer edges of the weapons bay doors have serrated edges that are designed to reduce the radar reflection from the joint between the doors and the fuselage belly. The weapons bay can accompany up to 5000 pounds of ordinance (2500 pounds in each well). Some of the loads accommodated in the F-117A’s weapons bay include two laser-guided MK84 2000-pound bombs, two laser-guided GBU-10 Paveway II 2000-poundbombs, two laser-guided GBU-12 Paveway II 500-pound bombs, two laser-guidedGBU-27 Paveway III 2000-pound bombs, two BLU 109 deep-penetration bombs, or two AGM130s. The GBU-10 Paveway II laser-guided bomb consists of a special nose and tail section attached to a standard 2000-pound Mk 84 high-explosive bomb. The tail section of the bomb consists of a set of folding aerodynamic surfaces which permit the bomb to glide, whereas the nose section includes a laser light seeker, guidance electronics, and control fins.
The GBU-24 Paveway III is a more advanced version of the Paveway II with a larger tail surface and a more efficient guidance system which permits it to be used at lower altitudes and at greater distances from the target. The BLU-109 deep-penetration bomb has a forged casing of hardened steel which permits it to pierce more six feet of reinforced concrete before exploding. When dropped on softer targets, theBLU-109 can bury itself deep into the ground before exploding, destroying its target by sending earthquake-like shock waves rippling through the ground.
The F-117A canal so carry up to two Mark 61 nuclear weapons, although the aircraft does not actually have an assigned nuclear mission. For long-range ferry flights, fuel tanks can be installed in the weapons bays in the place of bombs. The F-117A has no air-to-air capability, or at least none that has been announced to the general public. It has no radar, it does not carry an internal cannon, and is not equipped to carry or launch air-to-air missiles. The F-117A can in principle launch an infrared homer, provided the missile can be dropped from an extendable rack so that its seeker could acquire the target before launch. The F-117A cannot rely on radar for navigation, weapons aiming, or weapons delivery because the transmission of a radar signal would tend to give away the location of the aircraft and hence defeat the whole purpose of stealth. For low-level navigation and weapons-aiming purposes, the F-117 aircraft is provided with forward-looking infrared (FLIR) and downward-looking infrared (DLIR) systems. Both systems are built by Texas Instruments.
The FLIR is mounted in a recess just ahead of the cockpit front windshield. It is located in a steerable turret containing a dual field of view sensor. When not in use, the FLIR is rotated 180 degrees to keep prevent debris damaging the sensor. The DLIR sensor system is located in a recess mounted underneath the forward fuselage and to the right of the nose landing gear well. Both the FLIR and the DLIR recesses are covered by a RAM mesh screen to prevent unwanted radar reflections from the active elements. The edges of the recesses are serrated, with fasteners covered with RAM putty. The DLIR is provided with a bore-sighted laser for illuminating the target for attack by laser-guided weapons. Together, these systems form the infrared acquisition and designation system (IRADS).
The laser is slaved to the IRADS and is an integral part of the infrared system. The spot size of the laser on the ground is about 12-18 inches, and the spot is stabilized in position by the IRADS. A highly-accurate Inertial Navigation System (INS) backs up the sensors. This system uses an electrostatically-suspended gyro as the primary means of guidance. The INS guides the aircraft to the immediate target area and points the FLIR’s wide angle field of view toward the general location of the target. As the aircraft approaches the target, the pilot monitors the view presented by the FLIR on the heads-up display screen. When the specific target is identified, the pilot switches to the narrow view on the FLIR, and locks the screen of the display onto the target. As the target disappears underneath the aircraft, control is handed over to the DLIR, which acquires the target and continues to track it. When the pilot decides to attack, he releases a laser-guided Paveway bomb.
Approximately 7 to 10 seconds before bomb impact, the DLIR's laser is turned on and illuminates the target, and the bomb homes onto the reflected infrared laser light reflected from the target. Videotapes from the FLIR/DLIR displays that have been released to the public By the DOD have shown that the F-117A flying during a clear night can hit a target only one meter in size from an altitude of 25,000 feet.
A parachute braking system is provided, since the lack of flaps makes the landing speed quite high(160 knots, or 185 mph).The braking parachute is housed behind split doors atop the rear fuselage. The braking chute is deployed as soon as the nose wheel makes contact with the runway. The parachute can also double as an emergency antispin device if needed.
An in-flight refueling receptacle is added behind the pilot's cockpit. A small light is mounted near the receptacle to guide the refueling boom operator in nighttime refueling operations. Midair refueling is one of the more difficult aspects of F-117A flight, since it is always done at night and the F-117A pilot's upward vision is blocked by the canopy so that he cannot actually see the boom of the refueling aircraft.
The landing gear is of the standard tricycle type, with single wheels and tires that retract forward. The landing gear doors have serrated edges that help to reduce the radar cross section. A set of retractable communications antenna are fitted to the upper fuselage just behind the pilot. These are deployed during day flights, but are retracted for stealth missions at night. Detachable radar reflectors can be mounted on the fuselage sides so that local air traffic control can track the aircraft when it is not in stealth mode.
Some of the reports of the F-117A being tracked by radar during Desert Storm may have been due to the mounting of these reflectors.In 1991, persistent problems with the unorthodox exhaust system led to a decision to fit a new type of engine exhaust system involving the use of a new bottom side to the shelf-like extension over which the exhaust passes. The modification involves the use of new heat shields, better seals, new airflow paths, and new high-temperature thermal protection at the edge of the exhaust system. Most of these changes were designed to improve the maintainability of the exhaust system, which had proven to be a persistent problem.
During the production run of the F-117A, the two metallic all-moving tail fins were replaced with ones made of graphite thermoplastic materials. This change resulted from the loss of one fin and rudder from a F-117 in 1987 during a flight test. The aircraft landed safely despite the loss of the fin. The retrofit program was interrupted by Persian Gulf deployment, so most of the F-117s deployed to Saudi Arabia had the original metallic tail fins.
The cockpit of the F-117A has been recently updated and improved in accordance with advances in electronics and display technology. The original navigation system of the F-117A was the SPN/GEAS inertial navigation system .Later, this was replaced by a ring laser gyro and a global positioning system receiver. To improve the pilot's situational awareness, a Honeywell color multi-function display was fitted which had the capability of integrating a Harris digital moving map. Two cathode ray tube-based multifunction displays are used to call up digital maps, target photos, or target identification diagrams. A liquid crystal display data entry panel allows the pilot to select from 256 avionics functions. The new cockpit equipment is designed to minimize the chance of pilot disorientation at night time, which was suspected as the primary cause of two accidents involving operational F-117s.
In the early 1990s, auto throttles were added to provide the capability for arrival at a precise predetermined time over a target. This innovation was, however, not available in time for Desert Storm. The F-117A carries a three-digit serial number on the tail. The numbers are assigned in sequence, beginning with 780 and ending with 844. Aircraft 780 through 784 were full-scale development (FSD) aircraft, whereas 785 through 844 were production aircraft. The presentation of these numbers on the tail of the F-117A is sort of unusual, since the serial numbers of Air Force aircraft are typically presented as a combination of the last two numbers of the fiscal year in which the aircraft was ordered, followed by the last three digits of the aircraft's USAF serial number.
The tail numbers on the F-117A are NOT standard USAF serial numbers, that is, 780 is not a shorthand for something like 80-0780. They are part of a different sequence of serials that are used by the Defense Department for some special programs. However, Steve Pace claims the tail numbers ARE standard USAF serial numbers, and he includes a list of them in the appendix of his book. They are:
Lockheed F-117 AFSD80-1785/1791
However, it is rather odd that all of these different fiscal year numbers are in exact sequence! In addition, note that 1825/1828 falls in an earlier fiscal year than 1813/1824.
Two General Electric F404-GE-F1D2 non-afterburning turbofans,10,800 lb.s.t.
Maximum speed 700 mph at sea level (Mach 0.92).
Normal maximum operating speed is 648 mph at 5000 feet (Mach 0.87).
Combat radius 900 miles (unrefuelled)
Weights:30,000 pounds empty, 52,500 pounds maximum take off.
wingspan 43 feet 4 inches,
length 65 feet 11 inches,
height 12 feet 5 inches,
wing area 1140 square feet.
Up to 5000 pounds of ordinance can be carried in two internal weapons bays
This report on the F-117 stealth fighter concludes with an
account of its developmental and operational history, or at least that part of
it which has been released to the public. The results of the Have Blue testing
were sufficiently encouraging that William Perry, who was at that time
Under-Secretary of Defense for Research and Engineering in the Carter
Administration, urged the Air Force apply the technology to an operational
During November of 1978, Lockheed was awarded ago-ahead contract to begin full-scale development of the project. This was a “Special Access”, i.e. black, program, and the code name Senior Trend was applied to the project. The Senior Trend aircraft came to be defined as a single-seat night strike fighter with no radar, but with an electro-optic system for navigation and weapons delivery. No air-to-air capability was envisaged.
The first five Senior Trend aircraft built by Lockheed were to be preproduction full scale development (FSD) aircraft. The Senior Trend aircraft had the same General configuration as the Have Blue test aircraft, but was much larger and heavier. The engines were a pair of non-afterburning General Electric F404-GE-F1D2 turbofans. These were derivatives of the afterburning F404-GE-400 turbofans which power the McDonnell Douglas F/A-18 Hornet.
In early June of 1981, the first Senior Trend service test aircraft (tail number 780) was delivered to Groom Lake for testing. On June 18, 1981, Lockheed test pilot Harold C. “Hal” Farley made a successful first flight in number 780. During mid-1981 and early 1982, the other four FSD Senior Trend aircraft joined the program. They bore tail numbers 781 through784 respectively.
The first production Senior Trend (#785) arrived at Groom Lake in April of 1982. It differed from the pre-production Senior Trend aircraft in having a pair of enlarged fin/rudder assemblies, with three facets rather than just two. Aircraft number 785 was ready for its first flight on April 20, with Lockheed test pilot Robert L. Ridenauer scheduled to make the first flight. However, unbeknownst to anyone, the fly-by-wire system had been hooked up incorrectly (pitch was yaw and vice versa). Upon liftoff, Ridenauer’s plane immediately went out of control. Instead of the nose pitching up, it went horizontal. The aircraft went inverted and ended up traveling backwards through the air. Riedenauer had no time to eject, and the aircraft flew into the ground. Bob Riedenauer survived the crash but was severely injured and was forced to retire from flying.
The aircraft was damaged beyond repair, but some of its parts could be salvaged. It has been generally reported that since this aircraft crashed prior to USAF/TAC acceptance, it was not counted in the production total. This was not the case. It was, in fact, counted in the total production run. There were 59 production airframes and five pre-production full-scale development prototypes. The article numbers are 780 through 843. When it came time for the establishment of the first operational unit for the stealth bomber, the Air Force was faced with a problem. Groom Lake was too small to be useful as the base for an operational unit. In addition, there were security concerns because an operational unit based at Groom Lake would involve many more people who could now see things that they should not be seeing. Therefore, the USAF decided to build a new secret base for the stealth bomber on the Tonopah Test Range, which sits on the northwestern corner of the Nellis complex. The Facility is not perfect from a security standpoint, since it is overlooked by public land and is 32 miles from the town of Tonopah itself. However, the security surrounding the Tonopah Test Range was so effective that the new base was not public reported until 1985, after it had been operating for nearly two years.
The 4450th Tactical Group was secretly established as the initial operator of the stealth fighter. The cover for the 4450th was that it was a Nellis-based outfit flying LTVA-7Ds,which was not entirely inaccurate since the outfit did use these planes for support training. The group received its first production stealth aircraft on September 2, 1982.
The 4450th moved to Tonopah in 1983, equipped with a partial squadron of stealth bombers plus a few A-7Ds. The group achieved initial operational capability on October 28, 1983, with a total of 14 production aircraft on hand. To avoid having the 4450th’s aircraft seen by curious observers, all flying took place at night. During the day, the aircraft were always kept behind closed doors inside special hangars.
The stealth bomber turned out to be quite easy to fly, and it was concluded that no two-seat trainer version was required. However, there was a training simulator.
The Air Force considered using the stealth bomber in the invasion of Grenada during Operation Nickel Grass in 1983. However, the operation was so swift that the action lasted only a couple of days, and the combat debut of the stealth was put off. In October of 1983, the US government considered using the stealth fighter in are taliatory attack on Hezbollah terrorist forces based in southern Lebanon in response to the destruction of the Marine barracks in Beirut. In anticipation of action, the 4450th TG at Tonopah was put on alert. Five or seven stealth bombers were armed and had their INS systems aligned for attacks on targets in Lebanon.
The plan was for these planes to fly from Tonopah to Myrtle Beach, South Carolina where they would be put insecure hangars. They would then wait for 48 hours for the crews to rest before being given the order to take off for a nonstop flight to Lebanon. However, Defense Secretary Casper Weinberger scrubbed the mission 45 minutes before the aircraft were to take off for South Carolina.
On April 4, 1986, during Operation El Dorado Canyon, the United States attacked Libya in retaliation for state-sponsored terrorism. During the initial planning for the raid, the use of the still-secret stealth fighter in the operation was seriously considered. However, once again, the operation was short-lived and the stealth fighter was not used.
In spite of the extreme security, some bits and pieces of the stealth fighter story did manage to leak to the press. In October of 1981, Aviation Week reported that an operational stealth "fighter" was in development. Several people reported catching some fleeting glimpses of a rather odd-looking aircraft flying at night out in the western desert. More and more stuff leaked to the media, so that all through the 1980s it had been sort of an open secret that the USAF was operating a “stealth fighter” which was invisible to conventional radar. However, questions directed to the Pentagon by the press about the stealth fighter were met either with official denials or by a curt “no comment”, which only served to whet peoples’ curiosity even further.
The official designation of the rumored stealth fighter was assumed by just about everyone to be F-19, since that number had had not been assigned to any known aircraft. The novelist Tom Clancy placed the stealth bomber (named “F-19 Ghostrider” by him) in a key role in his techno thriller novel“ Red Storm Rising,” published in 1986. The Testors plastic model airplane company marketed a kit which purported to the true configuration of the “stealth” fighter. In the mean time, training continued out in the Nevada desert.
On July 11,1986, Major Ross E. Mulhare flew into a mountain near Bakersfield, California while flying production aircraft number eight (tail number 792). Major Mulhare seems to have made no attempt to eject and was killed instantly, his aircraft disintegrating upon impact. A recovery team was immediately dispatched to the crash site, and the entire area was cordoned off. Every identifiable piece of the crashed plane was found and removed from the area to prevent them from falling into the wrong hands.
The doomed aircraft had reportedly carried a flight data recorder, which is sort of unusual for a USAF fighter. Even though not much was found that was any bigger than a beer can, the flight recorder was supposedly recovered intact. The cause of the crash has never been officially revealed, but fatigue and disorientation during night flying has been identified as a probable cause.
On October 14,1987, while flying production aircraft number 30 (tail number 815), Major Michael C. Stewart crashed in the Nellis range just east of Tonopah. He too apparently made no attempt to eject, and was killed instantly. Again, the official cause was never revealed, but fatigue and disorientation may have both played a role. There was no moon that night, and there were no lights out on the Nellis range to help the pilot to distinguish the ground. Reportedly, the mission included certain requirements that were deleted from the final accident report. It is possible that Stewart was going supersonic when he crashed and that he had become disoriented during high-speed maneuvers and had simply flown his plane into the ground.
These two accidents, along with a need to better integrate the still-secret stealth fighter into its regular operations, forced the Air Force to consider flying the aircraft during daytime hours. This would in turn force the Air Force to reveal the existence of the aircraft. This announcement was originally scheduled to take place in early 1988, but internal Pentagon pressure forced a ten-month delay.
On November 10, 1988, the long-rumored existence of the “ stealth bomber” was finally officially confirmed by the Pentagon, and a poor-quality photograph was released. The stealth bomber was kept secret for over ten years, the security and deception being so effective that all descriptions which had “leaked” to the media were completely inaccurate.
On the same day, the Air Force confirmed that the official designation of the stealth bomber was F-117A, which surprised just about everyone. The official designation of the stealth fighter had long been assumed by just about everyone to be F-19, since that number had apparently been skipped in the new fighter designation sequence which was introduced in 1962. In addition, it had always been assumed that the designation F-111 had been the last in the old series of fighter designations which been abandoned in 1962 when the Defense Department restarted the whole sequence over again from F-1. This led to a seeming endless round of rumors and speculation about aircraft designation gaps and secret projects, which continue to the present day.
If the stealth bomber was not designated F-19, then just what was F-19? If the F-117A was part of the old F-sequence, then what happened to F-112 through F-116? The true answer is not yet known, but the most likely explanation is that the 117 number is NOT in the old F-sequence that ended in 1962 but instead originated from the radio call signs used by the Stealth pilots when they were flying out of Groom Lake and Tonopah, two of the black planes’ bases. Those are the same airfields that secretly operated Soviet- bloc Aircraft such as the MiG-15, MiG-19, MiG-21, and MiG-23 that the US had “acquired” by various means from such sources as Egypt, Israel, Romania, etc. While in flight, these aircraft were distinguished from each other by three-digit radio call signs (generally 11x). After awhile, these radio call signs came to be sort of unofficial designations for these aircraft, and even later, F-prefixes began to be attached to these designations.
The F-112 to F-116 are often speculated to be Soviet aircraft such as Su-22, MiG-19, MiG-21, MiG-23, or MiG-25. There is even a rumor that there exists a F-116A, which is a US-built version of the MiG-25 constructed to see what kind of threat the MiG-25 could be if Russia builds it using Western techniques. There is also thought to bean F-118, which might be a Mig-29 that was purchased before the fall of the USSR.
Since the stealth bomber was operating in the same general area in Nevada, it came to be known by the radio call sign of 117. The number 117 became so closely associated with the stealth bomber that when Lockheed printed up the first Dash One Pilot Manual, it had “F-117A” on the cover. Since the Air Force didn’t want to pay millions of dollars to re-do all the manuals, the aircraft became the F-117A officially. It may have even been initially designated F-19 in the early stages of the project, and might well have continued to be known as the F-19 had this mistake not been made. A similar mistake was made when LBJ announced the existence of the “Blackbird”. It was supposed to have been designated RS-71, but LBJ announced it as SR-71 and no one had the guts to tell LBJ that he had goofed. The designation stuck. This still leaves the question of the missing F-19 unanswered. Perhaps the F-19 refers to some other “black” project, as yet unrevealed. Perhaps the F-19does not exist at all, the designation having been deliberately or accidentally skipped. Shortly after the official revelation of the F-117, an Air Force spokesman answered questions about the “missing” F-19 by stating the F-19 designation had been deliberately skipped to prevent confusion with the Soviet MiG-19. Another possibility that has been mentioned by several people is that the F-19 designation was deliberately skipped in order to let Northrop receive the designation F-20 for its advanced version of the F-5 fighter. Apparently, Northrop thought that the F-20 designation would make for good advertising copy for its new fighter and the Air Force agreed. A similar thing happened during World War 2, when the designation P-74(and perhaps P-73 as well) were not assigned so that the Fisher Body division of General Motors could get the designation P-75 for its Eagle heavy escort fighter (“The French 75 in World War 1 --- The Fisher P-75 in World War 2”).
The 4450th Tactical Group was disbanded in October of 1989, and the 37th Tactical Fighter Wing was established in its place. The 37th TFW had three squadrons, the 415th, 416th, and 417th. The 415th and 416th squadrons flew production F-117As, whereas the 417th flew the pre-production F-117As. The 417th also operated some LTVA-7Dsfor chase and training, but T-38A and AT-38B aircraft eventually replaced them.
On December 19, 1989, just 13 months after the Pentagon disclosed the existence of the F-117A, it was used in combat for the first time. This was in Operation Just Cause, the invasion of Panama intended to dislodge and arrest General Manuel Noreiga. At the beginning of the invasion, six F-117As flew to Panama from Tonopah. Their mission was to drop 2000-pound bombs near the Panama Defense Forces (PDF) barracks at Rio Hato. The purpose of these bomb drops was to stun and disorient the PDF troops living there so that the barracks could be stormed and the troops captured with minimal resistance and casualties.
The pilots were instructed to drop their bombs no closer than 50 meters from two separate PDF barracks buildings. On the night of December 19, two lead F-117Aseach dropped a conventional 2000-pound bomb at the Rio Hato barracks. The bombing attack seems to have achieved its goal, since the barracks were quickly taken with minimal resistance. However, it was revealed three months later that one of the bombs missed its target by a considerable amount. It seems that there had been some miscommunication in the final stages of the mission planning, and the pilot had been given the wrong coordinates for the target.
The media jumped on this event and concluded that the F-117A had been a failure on its first mission. On April 21, 1990, stung perhaps by the press criticism, the Pentagon released more information on the F-117A. More photos of better quality were released, and at Nellis AFB there was a public display of twoF-117As. The last production F-117A was delivered to the Air Force on July 12,1990.
It was to be in Operation Desert Storm that the F-117A was to prove its mettle. In response to the Iraqi Invasion of Kuwait on August 2, 1990, the 415th TFS of the 37th TFW was deployed to Saudi Arabia on August 19, 1990. The 416th TFS followed in December of 1990. In January of 1991, a portion of the wing’s 417thTFTS was also deployed to Saudi Arabia.
In spite of the massive Coalition build up, President Saddam Hussein of Iraq stubbornly refused to withdraw his troops from Kuwait. On January 17, 1991, the Coalition began an air offensive to eject Iraqi troops from Kuwait. In the early morning hours, the F-117As of the 37th TFW initiated the air war against Iraq. Mission planners had assigned critical strategic Iraqi command and control installations to the F-117A, counting on the aircraft’s ability to hit precisely at well-defended targets without being seen. Other vital targets included key communications centers, research and development facilities for nuclear and chemical weapons, plus hardened aircraft shelters on Iraqi airfields.
On the first night of the war, an F-117A dropped a 2000-pound laser-guided GBU-27 Paveway III bomb right through the roof of the general communications building in downtown Baghdad. In another attack on the communications building next to the Tigris River, another GBU-27 Paveway III was dropped through an air shaft in the center of the roof atop the building and blew out all four walls. During the first three weeks of the air offensive, F-117As obliterated many hardened targets with unprecedented precision. The 37th TFW flew 1271combat sorties and maintained an 85.5 percent mission-capable rate. The 43F-117As of the 37th TFW dropped more than 2000 tons of precision ordinance and attacked some 40 percent of the high-value targets that were struck by the Coalition forces. Not one F-117A was hit, shot down, or lost to mechanical failure.
There is no evidence that the F-117A was ever detected or tracked by Iraqi radar installations, either ground or airborne. The F-117’s concealment, deception, and evasiveness proved that it could survive in the most hostile of environments, and its laser-guided bombs struck with extreme accuracy. Most of the F-117As deployed to Saudi Arabia returned home to Nellis AFB in April of 1991, but a few remain in Saudi Arabia. The F-117A is currently out of production, but the Senate Armed Services Committee expressed an interest in acquiring 24 additionalF-117As. However, the Air Force claimed that the F-117A is now "obsolete technology", and that it did not need or want any more of them.
In 1994,there has been some thought given to building a navalized version of the stealth fighter to replace the cancelled A-12 project. This would produce a new set of challenges for designers. The aircraft would have to have catapult attachment point sand arrester hooks and still be capable of maintaining the integrity of its stealthy exterior. Afterburning engines would presumably have to befitted to make carrier launchings with heavy payloads feasible, which would require that the complex exhaust system be completely redesigned. If this project is funded, it will be given the designation F-117N. However, no firm decision has yet been made.
Although the F-117A has been called Frisbee, Nighthawk, and Wobblin Goblin, there is no official name for it. Pilots often Nickname the F-117A the “BlackJet” .F-117A number 781 is now on Display at the Wright-Patterson AFB Museum at Dayton, Ohio. This was one of the five full-scale development machines. In the interest of security, the RAM covering was replaced by a layer of black paint, and the narrow slotted exhaust ports were faired over to prevent anyone peering inside to see the details of how the exhaust was constructed. Two F-117A FSD aircraft are still flying, the other two are in storage.
The F-117A Stealth Fighter, Steve Pace, Tab Aero, 1992. F-117AStealth Fighter, Andy Sun, Concord Publications Co.,1990. F-117 Stealth in Action, Jim Goodall, Squadron/Signal Publications,1991.Lockheed F-117A, Bill Sweetman and James Goodall, Motorbooks International,1990.Joe Baugher Lockheed F-117A : Have Blue Program
|See a broken link or error - Have a story or photo to add - - please let the webmaster know by E-mail
Posted Thornton D. BarnesBy Thornton D. Barnes Author Publisher