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Air Power |
The F-117A Nighthawk is the world's first operational aircraft designed to exploit low-observable stealth technology. The F-117A is a single-seat attack and defense suppression aircraft for the Air Force. The F-117 is designed to penetrate dense threat environments as well as attack high value targets with pinpoint accuracy.
The unique design of the single-seat F-117A provides exceptional combat capabilities. About the size of an F-15 Eagle, the twin-engine aircraft is powered by two General Electric F404 turbofan engines and has quadruple redundant fly-by-wire flight controls. Air refuelable, it supports worldwide commitments and adds to the deterrent strength of the U.S. military forces.
The F-117A can employ a variety of weapons and is equipped with sophisticated navigation and attack systems integrated into a state-of-the-art digital avionics suite that increases mission effectiveness and reduces pilot workload. Detailed planning for missions into highly defended target areas is accomplished by an automated mission planning system developed, specifically, to take advantage of the unique capabilities of the F-117A.
Constructed primarily of aluminum, the F-117A's fuselage comprises flat panels known as facets mounted on the aircraft's subframe, their purpose being to reflect radar energy away from the transmitter itself, thus denying the operators a visible 'return'. All surfaces are coated with various radar absorbent materials. All doors and panels have serrated edges to further minimize radar reflection. Grid covers on the intakes and the use of narrow-slot 'platypus' exhausts surrounded by heat-absorbing tiles further reduce the chances of IR detection. Ahead of the flat-plate five-piece cockpit glazing is a FLIR sensor, recessed in a mesh-covered housing; in the forward starboard underfuselage there is a retractable DLIR and laser designator. These sensors are used in conjunction with LGBs, two of which can be carried in the double-section weapons bay.
With the engines inside the fuselage, an extra effort must be made to inspect tor loose oblects or missing hardware before any engine run is attempted. This is not news to all those personnel who regularly work on or around this aircraft.
The Lockheed F-117A was developed in response to an Air Force request for an aircraft capable of attacking high value targets without being detected by hostile radar systems. By the 1970s, special materials and techniques had become available to aircraft designers that would allow them to design an aircraft with radar-evading or "stealth" qualities. Streamlined management by Aeronautical Systems Center, Wright-Patterson AFB, Ohio, combined breakthrough stealth technology with concurrent development and production to rapidly field the aircraft.
The first F-117A was delivered in 1982, and the last delivery was in the summer of 1990. The F-117A production decision was made in 1978 with a contract awarded to Lockheed Advanced Development Projects, the "Skunk Works," in Burbank, Calif. The first flight was in 1981, only 31 months after the full-scale development decision. Lockheed-Martin delivered 59 stealth fighters to the Air Force between August 1982 and July 1990. Five additional test aircraft belong to the company.
Air Combat Command's only F-117A unit, the 4450th Tactical Group, achieved operational capability in October 1983. Since the F-117’s first Air Force flight in 1982, the aircraft has flown under different unit designations, including the 4450th Tactical Group and the 37th Tactical Fighter Wing at Tonapah Test Range, NV; the 57th Fighter Weapons Wing, Nellis AFB, NV; the 410th Flight Test Squadron/410th Test Squadron, Palmdale, CA; and Detachment 1, Test Evaluation Group, also at Holloman, which falls under the 53rd Wing, Eglin AFB, FL.
The stealth fighter emerged from the classified world while stationed at Tonapah Airfield with an announcement by the Pentagon in November 1988 and was first shown publicly at Nellis in April 1990. The 4450th TG was deactivated in October 1989, and was reactivated as the 37th Tactical Fighter Wing.
In 1992 the F-117A Nighthawk made its new home at Holloman Air Force Base. The official arrival ceremony for the F-117 to Holloman AFB was conducted 09 May 1992. The 49th Fighter Wing (49FW) at Holloman serves as the only F-117 Home Station. The 49th Operations Group operates and maintains the F-117A aircraft. The 7th CTS "Screamin' Demons" serves as the transition training unit, preparing experienced Air Force pilots for assignment to the F-117A Nighthawk. The 8th and 9th Fighter Squadrons are designated to employ the F-117A Nighthawk in combat. Once an F-117 pilot has successfully completed training, he is then assigned to one of only two operational Nighthawk squadrons--the 8th FS "Black Sheep" and the 9th FS "Flying Knights." The 49FW provides full compliment of flightline maintenance capabilities as well as back-shop support. The F-117 deploys in support of contingency operations, as directed by National Command Authorities. Flightline maintenance support is deployed concurrent with the aircraft. Depending on the deployment duration, varying levels of back shop maintenance support may also be deployed.
The F-117A first saw action in December 1989 during Operation Just Cause in Panama. On 20 December 1989 pilots of the two F-117As flew to Rio Hato, Panama, to drop one 2,000-pound bomb each within 150 yards of the PDF’s 6th and 7th Rifle Company barracks to stun and confuse the occupants just before Rangers of Task Force RED parachuted into the area. Upon reaching the target area, the pilots encountered high winds coming from an unanticipated direction. The lead pilot swung to the left, and dropped his payload only sixty yards away from the barracks that was supposed to be the near target of the pilot in the second aircraft. Keying on the first pilot, the second pilot dropped his bomb further to the left, up to three hundred yards away from the target that had been originally assigned to the lead pilot. Despite the error, the bombs exploded precisely where aimed and momentarily stunned the PDF troops occupying the barracks.
The stealth fighter attacked the most heavily fortified targets during Desert Storm (January-February 1991), and it was the only coalition jet allowed to strike targets inside Baghdad's city limits. The F-117A, which normally packs a payload of two 2,000-pound GBU-27 laser-guided bombs, destroyed and crippled Iraqi electrical power stations, military headquarters, communications sites, air defense operation centers, airfields, ammo bunkers, and chemical, biological and nuclear weapons plants.
Although only 36 stealth fighters were deployed in Desert Storm and accounted for 2.5 percent of the total force of 1,900 fighters and bombers, they flew more than a third of the bombing runs on the first day of the war. In all during Desert Storm, the stealth fighter conducted more than 1,250 sorties, dropped more than 2,000 tons of bombs, and flew more than 6,900 hours. More than 3,000 antiaircraft guns and 60 surface-to-air missile batteries protected the city, but despite this seemingly impenetrable shield, the Nighthawks owned the skies over the city and, for that matter, the country. The stealth fighter, which is coated with a secret, radar-absorbent material, operated over Iraq and Kuwait with impunity, and was unscathed by enemy guns.
In response to a real world crisis, the wing’s F-117s began a deployment to Kuwait in November 1998, reaching an intermediate point in Europe before being turned around and sent back to Holloman.
In the opening phase of Allied Force, aimed primarily at Yugoslavia's integrated air defense system, NATO air forces conducted more than 400 sorties. During the first two night attacks, allied troops in the air and at sea struck 90 targets throughout Yugoslavia and in Kosovo. F-117 Nighthawks from the 8th Expeditionary Fighter Squadron at Holloman Air Force Base NM participated in air strikes against targets in the Balkans during NATO operations. The wing deployed 25 F-117A Nighthawks and more than 550 people to Aviano Air Base, Italy, and Spangdahlem Air Base, Germany, in support of the air operation. F-117s flew combat missions against the most highly defended, high value targets throughout the 78-day air campaign, including first-night attacks.
One F-117 fighter was lost over Yugoslavia on 27 March 1999. A US search and rescue team picked up the pilot several hours after the F-117 went down outside Belgrade.
An Air Force F-117A Nighthawk from the 49th Fighter Wing, Holloman AFB, N.M., crashed 7 miles south of Zuni, New Mexico, 10 May 1995. The pilot, Capt. Kenneth W. Levens, 9th Fighter Squadron, was killed in the crash. The stealth was on a training mission when the accident occurred.
The F-117A had an excellent year during FY96. There were no Class A's, only one Class B, and four Class C mishaps. This is an impressive record. The Class B resulted from a failed power takeoff (PTO) shaft. The pilot did an excellent job of determining the proper emergency procedures to follow and recovered a valuable national resource. The Class C mishaps involved a misrouted cross-bleed detector loop, failed oil pressure transducer, damage to a UHF antenna which occurred during air refueling, and failure of the right main landing gear upper scissor link.
From a historical perspective, by the end of 1996 there had been three Class A and three Class B mishaps in the F-117 world. This total included only those mishaps since the aircraft officially came into the Air Force inventory. The Class A's include a bleed air leak which eventually caused the pilot to eject, an engine fire due to an engine manifold leak, and failure to recover from an unusual attitude. The Class B's include a brake failure on landing roll which caused damage upon barrier engagement, a lost canopy during flight, and the failed PTO shaft.
Air Combat Command’s 1996 Senior Noncommissioned Officer of the Year was Master Sgt. Richard Acevedo. An 18-year veteran, Acevedo was the resource advisor for the 49th Maintenance Squadron, Holloman AFB, NM. Acevedo contributed to a 60 percent increase in the F-117A mission capable rate over the previous two years and reduced F-117A flight control computer testing and repair cycle time from 40 to three hours. He also managed the squadron’s 517 Government American Express accounts and funds for 44 temporary duty assignments. His efforts with the Aerospace Guidance and Metrology Center provided advanced training to Holloman members on Inertial Navigation System (INS) test station maintenance, saving the wing $123,300. He personally supervised dual-intensity modification on 26 F-117A display indicators with new checkout procedures, completing critical mission-essential time-change directives two months ahead of schedule.
In an effort to improve the combat effectiveness of the stealth fighter, test experts from the F-117 Combined Test Force at Air Force Plant 42 in Palmdale, Calif., are working to expand what it brings to the fight. On April 2 2002, developmental test experts in Palmdale teamed up with their operational counterparts from Holloman Air Force Base, N.M., to complete the second phase of a demonstration project designed to provide the F-117 and its pilots with the ability to receive and transmit mission and target data in real-time from the air. Phase one tests, completed in October of 1998, allowed a pilot to receive live-threat information and manually replan a mission from the cockpit. The second phase completed the test cycle by demonstrating the transmission of real-time mission and target data out of the cockpit and into the hands of command and control forces on the ground.
Until this testing, the potential time-critical combat capabilities of the F-117 had not been explored. The target data technology works by allowing the aircraft to receive and transmit tactical information on targets or pop-up threats via satellite communication. The fighter's ability to send and receive text and images enhances its combat flexibility yet does not compromise its stealth configuration.
The fleet of F-117As has been refurbished, including removing the aging thin films and coatings and replacing them with a special radar-absorbent paint that is easier and less expensive to apply and maintain. During manufacture, the thin films and coatings of radar-absorbent materials were painstakingly applied to each F-117A to ensure that no defects existed. Any slight deviation from the Nighthawk's exacting surface specifications -- even an air bubble or a screw not tightened exactly to specifications -- could result in a blip on an enemy's radar screen. The new painting process is no less exacting.
Nighthawks are large aircraft -- 65 feet long with a 43-foot wing span -- and each F-117A is slightly different from the others. The Nighthawk's angularity and the need to keep the paint spray nozzles at exactingly precise distances from the aircraft's surface at all times require both accuracy and adaptability to adjust for variabilities from one aircraft to another. Maintenance downtime for the F-117As needs to be minimized so that each fighter is available for military operations as soon as possible.
The first Nighthawk to be refurbished with the new coating was done manually by five painters and a masking crew, and took 4 and a half days. A Sandia National Laboratories development team created the system concept, identified the needed hardware, wrote the custom software that operates the system, and integrated the system's commercial and noncommercial components as part of a 3-year development project.
The first challenge in designing the automated painting system was to find a robot or robots big enough to reach all of the plane's surfaces. To keep costs down, the design team used commercially available equipment as much as possible. The Sandia painting system features three commercial robotic arms used in U.S. auto factories called the Motoman P8. Two of the arms are mounted on 30-foot-long rails. Each 10,000-lb robot-and-rail system is mounted on a specially designed air lift so that two people can move its base to desired locations around the aircraft. A paint nozzle at the end of each of the robotic arms is connected via tubes and wiring to an oversized stainless steel paint can. The coating-delivery system -- the paint nozzles, tubes, pumps, and cans -- is also a Sandia creation. One robot-rail combo paints the Nighthawk's top surfaces; the second paints the bottom surfaces. Cameras and other sensors help a nearby computer plan and guide the robots' every move. This merging of commercial hardware with Sandia-designed custom hardware and software exemplifies Sandia's unique system integration capabilities. The third floor-mounted, stationary robot is for painting the Nighthawk's removable parts, such as weapon bay doors and rudders.
The Sandia team developed a unique feedback, path-planning system that adjusts for variabilities from aircraft to aircraft. Path planning is the fruit of Sandia's years of research in "geometric reasoning," which was developed using DOE Defense Programs and Lab-Directed research funding. Geometric reasoning gives robots the capability to automatically determine the movements needed to carry out the task, even if the workpiece varies from piece to piece, as do the F-117As. A pair of stereovision cameras mounted at the end of the robotic arms locate "landmarks" on an F-117A corresponding to vertices where a Nighthawk's angular facets meet. Based on this feedback about the unique geometry of each plane and information about the robot's reach, joint limits, characteristics of the painting process and other factors, the software automatically generates a path for the robot to follow as it paints. The system also ensures that the robotic arms don't violate a 6-inch buffer zone around the fighter. The motion-planning software is what allows Sandia to rapidly and inexpensively develop robot systems for small-lot production operations like painting a limited number of aircraft.
To design the system, Sandia used a 3-D computer model of the F-117A provided by Lockheed Martin. Models permit the team to use Sandia's geometric reasoning software to perform a "reachability analysis" of the F-117A, which helped determine where the system's two robot-and-rail systems would have to be repositioned on the hangar floor to reach the entire aircraft.
Before painting begins and each time a robot-and-rail system is moved during painting, the computer vision system automatically registers reference points corresponding to three jack stands the Nighthawk is placed on inside the hangar. It then measures the precise locations of the two robot-and-rail systems with respect to the aircraft. With almost human-like agility, the rail-mounted robotic arms move with seven degrees of freedom. Six of those are the three spatial dimensions (x, y, and z) plus roll, pitch, and yaw, which is normal for many manufacturing-type robots. The seventh degree of freedom gives the robot the ability to maintain a fixed x, y, z, roll, pitch, and yaw position from multiple poses. This is like having an "extra elbow" to reach around things that are in the way. It also gives a large range of motion along the 30-foot rail required to coat a large aircraft.
The system was delivered to Lockheed Martin's Advanced Development Projects group, better known as the "Skunk Works," in September 1998. Members of the Sandia team helped install and acceptance-test the system during the following five months. Safety precautions are incorporated into the system and personnel are trained in robot awareness. In terms of size and level of complexity, this was the largest intelligent system Sandia has ever delivered to an outside customer.
Whereas the first aircraft was refurbished using five painters and a masking crew taking four and a half days, the first robotically painted aircraft at the Skunk Works took only three days with a smaller crew. Once it is in a production mode, the system will provide considerable cost and time savings to the Air Force. The new system also improved the final finish quality and reduce maintenance costs by minimizing the amount of time spent painting and reworking each aircraft. Signature testing was performed on the robot-sprayed aircraft and the results were significantly better than expected.
The Air Force, on 30 September 1998, awarded Lockheed Martin Skunk Works (LMSW) a sole source, Total System Performance Responsibility (TSPR) depot-level acquisition and sustainment weapon system support contract for the F-117 Stealth Fighter that provides stable logistics support into the next decade. This contract, beginning 1 October 98, continues the logistics support necessary to fulfill the weapon system mission, ensure combat capability and provide services presently performed by LMSW, breakout contractors and the System Program Office (SPO). This contract includes all support functions with the exception of Intermediate and Organizational maintenance.
The original concept for F-117 was for a Contractor Logistics Supported weapons system with a small SPO to oversee necessary government functions. Accomplishment of Program Management Responsibility Transfer (PMRT), in October 1989, moved the SPO from Wright-Patterson to the Sacramento Air Logistics command (SM-ALC). The ALC began the process of breaking out subcontractors and increasing technical oversight, generating considerable duplication of effort. All hardware, item management and distribution functions transferred to Sacramento creating a "third leg" in the weapon system support pipeline. SPO size ultimately increased to 226 providing sustaining management and contractor oversight.
LMSW presently provides 75% of the core sustaining for the F-117. All technical support is conducted under the annual sustaining contract and individual upgrade programs. LMSW also operates the modification/depot line at Site 7, AF Plant 42. These core capabilities provide a solid foundation for effectively increasing the LMSW Program Management role. TSPR expands LMSW responsibilities in the areas of system engineering, material management, subcontractor management, system & subsystem support, direct support to the user and AF reporting requirements. The majority of tasks scheduled to transition from the SPO are items already performed at LMSW. Government responsibilities will continue to include program direction, requirement determination, contract management, business/financial execution, product/service acceptance and security. The SPO size is targeted to reach 55 people by the end of FY99 with a goal of 20 by FY01 as LMSW demonstrates support capability. The TSPR contract will return the F-117 to the original concept -- Contractor Logistics Support with LMSW as the prime system integrator and a small SPO providing oversight capacity.
F-117 TSPR offers an incentive package to assure performance while encouraging the contractor to reduce costs. The contract will have a 3% Award Fee provision for subjective evaluation of technical, management, subcontracting and customer satisfaction. Grading is based on input from all aspects of the government including the SPO, ACC, the 49th Fighter Wing (FW) at Holloman AFB, DLA and DCMC. A 7% Incentive Fee provision based on seven performance metrics will track Non-Mission Capable Supply, MICAP rates, Readiness Spares Provisioning (RSP) Kit fill rates, Depot Quality, Depot Delivery, Delinquent Deficiency Reports and Weapons System Trainer Availability. All items are currently tracked by the 49th FW and SPO and are considered the most important indicators of program support. Finally, TSPR provides for 50/50 cost share between the government and LMSW on any under run with no ceiling. A minimum performance of 50% on metrics is necessary to receive any additional fee. Overruns are also shared 50/50 to the maximum of the Award and Incentive fees combined.
F-117 TSPR has been identified as a pilot program for the Air Force and DoD. This small fleet of 52 aircraft, located at a single operating location at Holloman AFB, offers a unique opportunity for the Air Force and LMSW to continue the F-117’s excellent program health. Timing for this transition is optimum due to the BRAC decision to close McClellan AFB, current location of the F-117 SPO. LMSW, as system integrator, will compensate for anticipated SPO program experience loss and complement a significantly downsized SPO with resident expertise. TSPR represents a departure from "business as usual" as it allows LMSW the flexibility required to manage sustaining funds, as appropriate, over the eight years of the contract with no degradation of the total program support posture. The contract makes LMSW accountable for complete weapons system support. TSPR challenges the company to provide support to the 49th FW that is "equal to or better than" current levels while reducing Total Ownership Cost to the US Air Force.
The F-117 program is the Air Force’s most complete application of Acquisition Reform initiatives and is successfully being operated with reduced government oversight. The program was implemented with a significantly reduced Air Force support capitol investment. The commitment of the Air Force to a long-term supplier relationship has allowed for optimal contractor investment.
A member of the 49th Fighter Wing made aviation history 02 November 1995 when he became the first operational Air Force pilot to log 1,000 hours in the F-117A Nighthawk. Lt. Col. Greg Feest, 9th Fighter Squadron commander, is a senior pilot with 3,350 total hours in the F-117, F-15, A-7 and AT-38, including 130 combat flying hours in the F-117.
On 21 November 1997, Major Ward Juedeman (Bandit 11) was returning to base from an F-117A day surface attack tactics training mission with approximately 15 minutes of fuel remaining. Maj Juedeman reported initial and set up for his base turn. After lowering the gear handle, Maj Juedeman noted that he only had a nose and right main gear down and locked indication with a red light in the handle. He quickly tested the lights, which checked good, and proceeded to break out of the overhead pattern leaving the gear down. Maj Juedeman declared an emergency, switched to the single frequency approach, and requested a safety chase. Since no other aircraft were airborne, the supervisor of flying immediately launched a T-38A that was taxiing for takeoff. After rejoining with the safety chase, Maj Juedeman was informed that the nose and right main gear were indeed down and locked with the left main gear up and the gear door closed. Referencing the checklist, Maj Juedeman attempted to raise the landing gear, but neither gear moved, leaving the aircraft in a configuration which recommends ejection. Maj Juedeman put the gear handle back down with no effect, and then attempted to lower the gear using the landing gear emergency extension system. After approximately 5 seconds the left main gear unlocked, deployed by gravity and air loads, and appeared to lock into place. Maj Juedeman then flew a flawless straight-in approach and landing.
An Air Force F-117A Nighthawk crashed 14 September 1997 while performing a fly-by demonstration for an airshow at Martin State Airport, 12 miles northeast of Baltimore. The pilot, Maj. Bryan Knight, safely ejected. He suffered minor injuries. Four people on the ground were injured and 10 families displaced by the crash, which caused extensive fire damage to several homes and vehicles. There were no fatalities or serious injuries. The aircraft had just completed its third pass of an air show flyover at Martin State Airport near Baltimore. The pilot was initiating his climb out for departure when he felt the aircraft shudder and the left wing broke off. The accident investigation report concluded that the cause of the accident was structural failure of a support assembly, known as the Brooklyn Bridge, in the left wing due to four missing fasteners of the 39 in the assembly. The Brooklyn Bridge assembly was apparently improperly reinstalled during a scheduled periodic inspection in Jan. 1996. The entire fleet of 53 F-117 Nighthawks was inspected during a command-directed precautionary stand down and none were found to have the same defect.
The F-117 stealth fighter completed flying its 150,000 flying hour when Brig. Gen. Bill Lake, 49th Fighter Wing commander, touched down on Holloman's runway 25 August 1998. The flying milestone was measured from the first F-117 flight by Lockheed Martin test pilot Hal Farley on June 18, 1981. The first Air Force pilot to fly the F-117 was then Maj. Al Whitley on Oct. 15, 1982.
The F-117A program has demonstrated that a stealth aircraft can be designed for reliability and maintainability. The aircraft maintenance statistics are comparable to other tactical fighters of similar complexity. Logistically supported by Sacramento Air Logistics Center, McClellan AFB, Calif., the F-117A is kept at the forefront of technology through a planned weapon system improvement program located at USAF Plant 42 at Palmdale, Calif. The F-117A Combined Test Force is a diverse organization that includes military members, government civilians and various contractors who work together to test the latest F-117 improvements. The test force works out of U.S. Air Force Plant 42 in Palmdale, Calif, just south of Edwards. As a reflection of the Nighthawk itself, the F-117A Combined Test Force maintained a stealthy profile when it first began testing the revolutionary plane.
A recent CTF project involved testing an improved navigation system for the F-117A. Now operational, that system is a prerequisite on all deployed F-117As. The Lockheed Martin Skunk Works delivered the first F-117A configured with a new navigation system to the 49th Fighter Wing in January 1997. Dubbed "RNIP-Plus," the Ring Laser Gyro/Global Positioning System Navigation Improvement Program reduces the drift pilots experience during flight. Drift is when an aircraft's navigation system wanders off its intended flight path -- a computer problem in the older Inertial Navigation Systems. Not only does the RNIP-Plus boost navigation, it also strengthens the F-117A's targeting capability. The configuration includes a new control display navigation unit in the cockpit allowing the pilot to quickly reference and check flight data. The control display also collects and stores maintenance data on the INS and GPS, a plus for post-mission maintenance.
In another recent project, F-117A experts tested a real-time information into the cockpit capability for the Nighthawk that will now allow real-time communication with the outside world while the plane is in stealth mode. This capability includes integration of a new real-time symmetric multi-processor, which allows onboard mission planning at faster computation times than current ground mission planning. If this new technology is put into the aircraft, the pilot will have the ability to adjust his mission based on changing threats and targets, a capability previously unavailable.
The Advanced Composites Program Office (ACO) at Hill AFB led an in-house effort to reduce cost of ownership of F-117A composite structures. As a high-usage trailing-edge component, the 20D82 is required to endure high temperatures from the engine exhaust. Problems with this component included short service-life, high cost, poor fit, large part-to-part variances, and lack of repair procedures. The latter forced the Air Force to replace the component at a cost of $46,400 per item until effective field and depot level repair procedures were developed by the ACO, working with the F-117A System Program Manager (SPM) and SM-ALC/TIM composite manufacturing personnel. Each component repair costs approximately $4,200. After providing a repair, the team set out to totally redesign the troublesome component. They were able to simplify the design, increase service temperature capability, maintain low observable requirements, and reduce the assembly part count from fifteen to six. The cost of the redesigned component is half of the original cost for twice the capability.
The Single Configuration Fleet (SCF) program is intended to reduce the total ownership costs of the F-117 by standardizing the fleet to a single optimized spray/sheet coating and edge configuration. The Single Configuration Fleet modification consolidates the existing seven different F-117 radar-absorbing material configurations into one optimized for maintainability and deployability. This will reduce LO maintenance requirements and take advantage of state-of-the-art robotic technology. The F-117's low-observable features have always been costly and difficult to maintain because of the various radar-absorbing material configurations. To correct this, the Single Configuration Fleet modification consolidates the existing seven different radar-absorbing material configurations into one optimized for maintainability and deployability.
The modification, entailing stripping and re-coating the entire F-117 fleet, replaces the sheet-coated RAM on the wings, rudders and fuselage and uses a precise robotic process to apply a RAM coating to almost 75 percent of the airframe, he said. These areas which are never accessed for maintenance will require virtually no future RAM repairs. Areas that are frequently accessed will have removable RAM sheets applied to the maintenance panels. The new spray-coated RAM is much more durable than previous versions of sheet-coating. This will result in the new (Single Configuration Fleet) aircraft requiring fewer RAM repairs. The optimized configuration provides maintainers easy access to maintenance panels while eliminating the need to repair infrequently accessed areas.
The biggest advantages of the new standardized configuration, for maintainers and the Air Force, will be common repair procedures and materials for all F-117s. Currently, with so many configurations, there are numerous repair procedures and materials. Maintainers must keep track of which procedures and materials belong to which aircraft. Maintaining the aircraft will be much easier once the entire fleet undergoes its modification. The Air Force should also see a 50 percent reduction in the size of our technical order -- the manual airmen must follow step-by-step when working on aircraft maintenance.
The new modification also will greatly reduce the amount of hardware and other supplies that units will need when they deploy to forward locations. The Air Force will be able to phase out a number of materials leading to further cost savings in the logistics and materiel management. Based on flight test results and an initial operational evaluation, the new SCF configuration will reduce maintenance manhours per flying hour due to (RAM) maintenance by over 50 percent. Since low observability is the primary maintenance driver for the F-117, the SCF improvements will indirectly improve sortie generation capability. Additionally, once SCF is implemented in the entire F-117 fleet, the annual consumable material costs will be reduced from the current level of $14.5 million to approximately $6.9 million.
The modification is being implemented on a five-year schedule as the F-117s are rotated through the contractor depot at Palmdale, CA. To make best use of this time, the Air Force is also implementing numerous other F-117 modifications and repairs. The entire process takes approximately five months for each aircraft. The first completed production aircraft to undergo the modification was delivered to Holloman in April 2000. Holloman is the only base in the Air Force that flies the F-117.
With a goal to obtain MK-84 and BLU-109 Joint Direct Attack Munitions weapons certification for the F-117A Nighthawk aircraft, the Seek Eagle Office at Eglin AFB, Fla., sponsored a weapons separation test in AEDC's 4-foot transonic aerodynamic wind tunnel. Additional test customers included Lockheed Martin Skunk Works, manufacturer of the F-117A, and Boeing, St. Louis, manufacturer of the JDAM weapons system.
Lockheed-Martin Aero modifies nine F-117 aircraft per year at its Palmdale facility. The Air Force thinking is that it will phase out the Nighthawks after 2018.
Specifications:
Primary Function: Fighter/attack
Contractor: Lockheed Aeronautical Systems Co.
Power Plant: Two General Electric F404 engines
Unit Cost FY98: $122 million
Crew: One
Date Deployed: 1982
Inventory: Active force, 54; ANG, 0; Reserve, 0
Dimensions:
Length: 65 feet, 11 inches (20.3 meters)
Height: 12 feet, 5 inches (3.8 meters)
Weight: 52,500 pounds (23,625 kilograms)
Wingspan: 43 feet, 4 inches (13.3 meters)
Performance :
Speed: High subsonic
Range: Unlimited with air refueling
Armaments:
Internal weapons carriage with two each of:
