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July 1990, Vol. 73, No. 7
After nearly ten years of flying--and one combat mission--the
F-117 finally appears in public.
The Black Jet
By Jeffrey P. Rhodes,
Aeronautics Editor
THE Air Force and Lockheed got the F-117 A fighter built and
flying in a mere thirty-one months, but kept it under wraps for
eleven years. Now the world is getting its first close look at
one of history's most unusual combat aircraft.
Nearly a dozen years ago, in December 1978, the Air Force decided
to develop a full-scale, radar-evading fighter. First flight came
in June 1981. Only in November 1988, however, did the Pentagon
even acknowledge that the F-117A existed, and then it said little
more than that the aircraft had been built for maximum stealthiness.

The Lockheed F-117 A may look as if it were built for use by
alien beings, but it is actually flown by flesh-and-blood humans
like Capt. Phil McDaniel (above), a pilot with the 37th Tactical
Fighter Wing. (Staff photo by Guy Aceto) |
This spring, the curtain of secrecy finally began to part.
On April 21, two F -117 pilots flew their planes from Tonopah
Test Range, Nev., to Nellis AFB, Nev. They circled, touched down,
and taxied to a reviewing stand filled with onlookers. It was
the first time anyone outside the program, including the families
of the unit's pilots and maintainers, had seen the mysterious
F-117 up close.
In the mid-1970s, the Defense Advanced Research Projects Agency
provided funding for development of an airplane that would feature
low radar, optical, and infrared signatures to counter the increasing
sophistication of Soviet radar and surface-to-air missiles. The
classified program, called Have Blue, produced and flew several
subscale proof-of-concept air vehicles.
Soon after, the Air Force decided to proceed into full-scale
development. Lockheed's Advanced Development Projects (ADP) section--popularly
known as the "Skunk Works "--got the task of building
a production "stealth" fighter. "It is an odd-looking
flying machine," says Ben Rich, Lockheed's executive vice
president and general manager of the Skunk Works, "but we
got it operational in record time."
Fast Track, Tight Secrecy
Using streamlined management methods and operating under tightest
secrecy, cadres from Lockheed and Air Force Systems Command's
Aeronautical Systems Division cooperated closely to get the F-117
built and flying just two and a half years after work began. Bill
Park, Lockheed's chief test pilot, took the F-117 aloft for the
first time on June 18, 1981, Mr. Rich's fifty-sixth birthday.
The buildup of aircraft was swift. The 37th Tactical Fighter
Wing (known then as the 4450th Tactical Group) achieved initial
operational capability with the F-117A on October 26, 1983, a
mere twenty-eight months after first flight.
"Using proven components from other aircraft allowed us
to reduce risk," notes Mr. Rich. "This gave us confidence
to proceed concurrently with full-scale development and low-rate
production." Such components either were transferred directly
to the F-117 or were used in modified form.
Some of the components modified for the F-117 include its quadruple-
redundant flight-control system (based on the one in the General
Dynamics F-16) and cockpit environmental control system (a portion
of the ECS in a Lockheed C-130). The F-117's two General Electric
F404-GE-FID2 engines are nonafterburning derivatives of the powerplant
in the Navy's McDonnell Douglas F/A-18 fighter/attack aircraft.
Examples of direct transfers include the F-117's inertial navigation
system (the same highly accurate one used on a B-52), its ejection
seat (the McDonnell Douglas ACES II seat found in F-15s, F-16s,
and A-10s), and its brakes (the same type used on a Gulfstream
III executive jet). Many of the plane's avionics black boxes were
also taken directly off the shelf.
"The Skunk Works gave us a perfectly usable product as
quickly as possible," says Lt. Gen. Peter T. Kempf, commander
of 12th Air Force. He adds that Lockheed did not attempt to deliver
a "perfect" airplane, an effort that surely would have
brought long delays in deployment of a "good enough"
aircraft.
For developing and fielding the F-117 in complete secrecy and
at such a rapid pace, the National Aeronautic Association awarded
the 1989 Collier Trophy, the most prestigious award in American
aviation, to Mr. Rich and the entire Air Force/Skunk Works team
this past spring.

Any way you look at it, the F-117A is an unusual aircraft. Its
design and development were also out of the ordinary. The F-117
is the first aircraft to exploit low-observable, or stealth,
technology. Here, an F-117 tanks up in flight, just as those
on their way to and from Panama did several times last December. |
Hide in Plain Sight
"The F-117A is a one-mission, unique aircraft," says
Col. Tony Tolin, the 37th TFW Commander. "It is flown autonomously
at night, to go after high-priority targets with pinpoint accuracy.
It is not a close air support platform." The Colonel concedes,
however, that "it sure doesn't look like any other aircraft."
What gives the F-117 its unusual look is its faceted design.
The planar surfaces set at unusual angles scatter incoming radar
beams instead of reflecting them to a source. This dramatically
reduces the aircraft's radar cross section, which is an object's
"footprint" on a radarscope. The Northrop B-2 Stealth
bomber, on the other hand, uses compound curves to achieve the
same effect.
Additionally, the F-117's primary structures, thought to be
made mostly of aluminum, are covered by radar-absorbent material
(RAM). The material soaks up radar beams, yielding minimal reflection.
Other major F-117 structures, such as fully movable (above the
fuselage join) V-tail ruddervators, are made of radar-resistant
composites.
Designers also "buried" the engines in the fuselage
and put the highly radar-reflective turbine blades behind intake
screens equipped with faceted crosspieces. The F-117 has auxiliary
intake doors on the fuselage above and behind intake screens.
They are opened on taxi, takeoff, and landing to allow more air
to feed into the engines.
The plane's infrared (heat) signature has been reduced. First,
hot engine exhaust mixes with bleed air to cool it. Then the air
is dispersed through baffles in the harmonica-like tailpipes. In
addition, a "ledge" fixed on the bottom of the fuselage
directs the exhaust upward, further reducing the IR signature.
The nozzles can only be seen from above.
Two other methods of detecting aircraft--visual and acoustic--have
been addressed. RAM on the exterior offers a dull black finish
that reflects little light, and the engines produce almost no
smoke. Buried engines and absence of afterburners make the F-117
extremely quiet. At the Nellis flyby, the two aircraft sounded
much like business jets as they circled. Only when the first pulled
up after its near touch-and- go landing was any significant noise
heard.
Little detail emerged about how the airplane performs its mission.
The aircraft does have what appears to be a steerable forward-looking
infrared set under the windscreen (allowing the pilot to see at
night or in bad weather). The F-117 apparently does not have a
radar.
The cockpit features a head-up display; Capt. Joe Salata, a
37th TFW pilot, notes, "We are very proficient on instrument
flying." Officials would not comment on the use of or need
for night vision goggles. The digital avionics suite is complemented
by a specially developed automated mission planning system.

The "TR" on this F-117 means it is based at Tonopah
Test Range, Nev., where much of what goes on remains shrouded
in mystery. |
The glazing in the rear-hinged, upward-opening canopy has a
reddish- bronze tint, indicating electromagnetic interference
protection. "You can't see much of the fuselage from the
cockpit," says Capt. Philip McDaniel, a 37th TFW pilot. "It's
like riding on the tip of a spear." The canopy's apex appears
to be either a periscope for improved rearward visibility or a
light to illuminate the air-refueling receptacle.
A shallow depression on the fuselage underside on the right
side of the nose-gear well appears to be a laser designator for
directing the plane's ordnance, which is carried in an internal
bay. The F-117 has been described as being capable of carrying
a wide variety of tactical weapons, including some specifically
designed (or, more likely, modified) for the airplane.
Officials did not disclose what types of munitions are used.
The two F-117s used in Operation Just Cause (the F-117A's first
use in combat) each dropped a single BLU-109/B 2,000-pound bomb.
Officials say the F-117 has a self-defense capability, but close
examination did not reveal an external gun port. Self-defense
may hinge on the plane's stealthiness and evasive tactics, though
it probably has an internal jammer and chaff and flare dispensers.
The size of the F-117 slightly exceeds that of an F-15, both
in wingspan (the F-117's forty-three feet, four inches, vs. the
F-15's forty-two feet, 9.75 inches) and in length (sixty- five
feet, eleven inches, vs. sixty-three feet, nine inches). With a
height of twelve feet, five inches, the F-117 stands shorter than
the F-15's eighteen feet, 5.5 inches. The F-117, at 52,000 pounds
gross, weighs in 18,000 pounds under the F-15C.
The F-117's wings feature split, wide-chord flaps, swept back
at an angle of about sixty-seven degrees. The aircraft, which
flies on JP-4 aviation fuel, has a tailhook for barrier engagements
and, in a throwback to earlier days, a drag parachute. The parachute,
located in a recessed fuselage compartment just forward of the
fins, is released when the nose wheel hits the ground on landing.
The main canopy is pulled clear of the tail by a small drogue.
Just Call It "Black Jet"
All of the 37th TFW pilots present at the ceremonies at Nellis
this past spring praised the aircraft's handling and maneuverability.
They strongly refuted claims that the airplane is not very nimble,
a belief that has led some outsiders to coin the name "Wobbly
Goblin" for the F-117A. Captain Salata maintains that its
handling is similar to that of other Air Force aircraft. "We
take offense at the term 'Wobbly Goblin.' We just call it 'the
Black Jet.' " The F-117 has no official nickname, though
"Nighthawk" is in popular use among crews and maintainers.
Getting the F-117 on the ramp is one thing, but learning to
operate and fix it is another. The F-117 program, in fact, had
more concurrency (simultaneous procurement and development of
a system) than the B-2 development effort has now. "The learning
curve was just not there in the beginning," notes Colonel
Tolin. "But we are now close to maturity with the aircraft."
In the eighty-one months since the F-117A achieved IOC, mission
reliability (the probability of successful completion of a mission
and dropping weapons with specified accuracy) has improved forty-eight
percent. Maintenance hours per flight hour has improved sixty-nine
percent. The wing's fully mission-capable rate now compares favorably
with that of a typical F-15 or F-16 wing.
One maintenance item peculiar to the 37th TFW is the radar-absorbent
material. All F-117 access panels are covered by RAM, which must
be removed to reach the F-117's insides (and must later be replaced).
Ninety-five percent of needed tools come right out of the standard
toolbox, but some special items, possibly for working with RAM,
are needed.
"We learned as we went along," says TSgt. Randy Charland,
an F-117 crew chief. "The more we learned, the better we
got, and the easier it became. All the systems are fairly accessible
and are very reliable."
"There is no depot maintenance program so far," says
Capt. William Ogden, the officer in charge of the 37th TFW's 415th
Aircraft Maintenance Unit. "What we have been doing is upgrading
the aircraft. The airplanes are taken to Palmdale [Calif., to
Lockheed's facility at Air Force Plant 42] to do the upgrades,
and we will continue to do that." The Sacramento Air Logistics
Center at McClellan AFB, Calif., oversees upgrades.
Every Plane Is Different
Each aircraft emerged from Lockheed's Burbank, Calif., assembly
plant slightly different from every other. One F-117 would get,
for example, a new type of digital moving map, color multifunction
displays, or autopilot, and the system would later be retrofitted
on others. One modification in progress will replace the aircraft's
ruddervators with fins made of a new, stronger, thermoplastic
graphite composite.
The last of fifty-nine F-117 As will be delivered soon. The
Air Force recently revealed the final cost of the program (called
Senior Trend in classified budget documents) to be $6.56 billion
in current dollars--nearly $2 billion in development costs, $4.27
billion in total procurement costs, and $295.4 million in military
construction costs. By Air Force calculations, the F-117's unit
cost came to $42.6 million.

The faceted shape and radar-absorbent material covering give
the F-117 its low radar cross section. The plane's exhaust (to
the left of the movable ruddervators) can only be seen from above.
Several measures, such as "burying" the engines and
dispersing exhaust through baffles, are taken to reduce the efflux. |
To date, every F-117 has been delivered in unusual fashion--at
night, in the cargo hold of a C-5-to its base at Tonopah, Nev.,
160 miles north of Las Vegas. The airfield is about ten years
old and has a 12,000-foot runway, fifty-four hangars, and about
a dozen other buildings. Once part of a California oil-drilling
site, the buildings were bought from Chevron for $1.5 million
and packed off to Tonopah. A separate housing area for the wing's
2,500 military personnel and 1,000 civilians was later constructed.
Once a week for eight years, F-117 pilots and maintainers living
on or near Nellis would pack up, say goodbye to families, board
a contract 727 run by Key Air, and go to work. Four days later,
they would return. Wing members could not tell anyone, except
those directly involved in the program, where they had been or
what they had done.
Flyers and fixers adapted to a night-shift routine. "On
Monday night, when we are unsure about their crew rest, pilots
only fly one sortie, and they are finished early," says Colonel
Tolin. "On Tuesday, when we have a guarantee of their crew
rest, we can go longer into the night." Dorms are locked
and have blacked-out windows to ensure that the crews get enough
sleep.
Early on, work often did not begin until an hour after sunset,
the better to ensure secrecy. "After the plane was revealed,
we could start at sunset and fly longer," adds Colonel Tolin.
"We could also fly and train in the day. It is a lot easier,
especially on your first ride in a single-seat airplane, if you
can see outside."
First flight is aided by a highly realistic simulator built
by Link. "We don't have any two-seat F-117s," says Colonel
Tolin, "so if you can fly the simulator, you can fly the
aircraft." The simulator is also helpful in developing cross-check
habit patterns for the F-117's unusual cockpit layout.
The F-117's cockpit-panel design is cited as a contributor
to two operational accidents, in July 1986 and October 1987. Spatial
disorientation was the primary cause of both. A third F-117 was
lost in an accident prior to delivery. Three mishaps in nine years
of flying gives the F-117 one of USAF's best safety records.
Nothing but Volunteers
All 37th TFW personnel are volunteers who undergo thorough
screening before starting their three-year tours. Pilots must
have at least 1,000 hours of flight time, an indicator of maturity
in the cockpit. Pilots fly with one of two operational squadrons,
the 415th and 416th TFS. The F-117 "schoolhouse," the
417th Tactical Fighter Training Squadron, familiarizes pilots
with the plane.
Each month, pilots in the two operational squadrons get fifteen
to twenty hours of flying (mostly at night) and perform two or
three night air refuelings. Dual-qualified pilots get an additional
five or six hours in Northrop AT-38Bs assigned to the wing. These
totals are slightly less than TAC's average.
New maintainers enter a school at Tonopah, complete with part-task
trainers, and come out fully qualified. They then go through an
on-the-job training program at one of the aircraft maintenance
units.
To further incorporate the F-117 into the operational warplans,
the wing has participated in one Blue Flag (tactical air warfare
battle management) and two Red Flag (basic tactical fighter employment)
exercises in recent months.
The F-117 has also been involved in one real-world action,
with less than stellar results. Prior to the Army attack on the
Panamanian Defense Force barracks at Rio Hato during Operation
Just Cause, two F-117 pilots were to drop their bombs within fifty
feet of the building to "stun, disorient, and confuse"
PDF troops. The attack plan changed at the last minute, and, as
a result of confused communications, the first F-117 pilot dropped
his bomb where the second pilot was to drop his. The second pilot,
thinking the attack had reverted to the original plan, dropped
his bomb 325 yards wide.
The Air Force, violating a cardinal tenet of air warfare, apparently
did not perform a battle damage assessment, and word of "direct
hits" was passed to Washington. When Secretary of Defense
Richard Cheney was shown pictures of the locations of the craters,
he ordered an investigation, the results of which had not been
concluded by late spring.
The F-117 surely will become more visible. In the third quarter
of FY 1992, the 37th TFW is scheduled to move to Holloman AFB,
N. M., which is a much more accessible and public base. The 37th
TFW will replace the 479th Tactical Training Wing at Holloman,
which will be deactivated. The move will eliminate the need for
Key Air, which is currently flying 22,000 passenger trips on 300
flights to Tonopah per month.
Copyright Air
Force Association. All rights reserved
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