Subject: Number 117 in the Series--Lockheed F-117 (1 of 3)

From: [email-masked]
Date: 23 Mar 94 17:58:22 GMT

>From [email-masked]

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 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 Work engineers began working on an aircraft which 
would have a greatly reduced radar cross section that would make it 
all but invisible to enemy radars, but would nevertheless still be 
able to fly and carry out its combat mission.  The technique that 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 aircraft 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 aircraft which was inherently 
unstable about all three axes--pitch, roll, and yaw.  

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, noone knew that 
*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 some time 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 which were 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 when they were being 
tested 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 to 10,000 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.  The wreckage was secretely 
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 1890, 
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.  

It was found that the application of the RAM was rather tricky, and 
that ground crews had to be careful to seal all joints thoroughly 
before each flight.  RAM came in linoleum-like sheets which was 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 show up like a "barn door 
coming over the horizon" 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 fire got so intense that the hydraulic 
fluid lines were burned through.  Lt.Col. Dyson was forced to eject, 
and 1002 was a total loss.  It too was secretely buried somewhere on 
the Nellis test range complex.  

No further *Have Blue* aircraft were built, since the general concept 
had been proven.  

Specification of the *Have Blue* (approximate): 

Two non-afterburning General Electric J85 turbojets.  Maximum speed: 
600 mph at sea level.  Dimensions: wingspan 22 feet 0 inches, length 
38 feet 0 inches, height 7 feet 6 inches.  Gross weight 12,000 pounds.  
No armament was carried.  Most other details are still classified.  

Sources:

  The F-117A Stealth Fighter, Steve Pace, Tab Aero, 1992.

  F-117A Stealth Fighter, Andy Sun, Concord Publications Co., 1990.

  F-117 Stealth in Action, Jim Goodall, Squadron/Signal Publications,
  1991.

  Observers Aircraft, William Green and Gordon Swanborough, Frederick
  Warne, 1992.

  Lockheed F-117A, Bill Sweetman and James Goodall, Motorbooks
  International, 1990.  

Joe Baugher		AT&T Bell Laboratories   	
2000 North Naperville Road      Naperville, Illinois 60566-7033