Article 4055 of sci.military:
Xref: ssbunews sci.military:4055
Newsgroups: sci.military
Path: ssbunews!nntpa!gw1.att.com!fnnews.fnal.gov!mp.cs.niu.edu!vixen.cso.uiuc.edu!howland.reston.ans.net!news.sprintlink.net!uunet!ranger!military
From: uscbu.ih.att.com!jfb (Joseph F Baugher) 
Subject: New Fighter Series--McDonnell Douglas F-15 Eagle (10 of 26)
Message-ID: <D3pMED.F3J@ranger.daytonoh.ncr.com>
Sender: military@ranger.daytonoh.ncr.com (Sci.military Login)
Organization: AT&T Global Information Solutions
Date: Thu, 9 Feb 1995 01:49:25 GMT
Approved: military@ranger.daytonoh.ncr.com
Lines: 275


From uscbu.ih.att.com!jfb (Joseph F Baugher) 

In the late 1970s, McDonnell Douglas and Hughes Aircraft collaborated 
in a privately-funded study of the feasibility of adapting the basic 
F-15 Eagle to the air-to-ground role.  Back in the late 1960s, the 
F-15 had originally been conceived as a multi-role aircraft, but the 
fighter role had become paramount, and in 1975 the air-to-ground role 
had been set aside.  

As part of this program, the McDonnell Douglas company converted the 
second F-15B (71-0291) under a project known as *Strike Eagle*.  The 
aircraft first flew on July 8, 1980.  It was equipped with a modified 
APG-63 radar that equipped to use synthetic aperture radar techniques 
to do high-resolution ground mapping.  The back seat was configured 
for a Weapons System Officer (WSO) who would operate the weapons 
delivery systems.  The aircraft was equipped with the FAST conformal 
fuel tanks that had been introduced on the F-15C/D.  The aircraft was 
equipped with six stub pylons on the lower corners and on the bottoms 
of each of the FAST packs for the carriage of bombs.  

The *Strike Eagle* prototype was later equipped with a centerline gun 
pod and was provided with a *Pave Tack* laser designator pod (as 
carried by some F-4Es and F-111Fs) carried on the port side of the 
forward air intake.  This made the aircraft capable of delivering 
"smart" laser-guided bombs without the assistance of a separate 
designator aircraft.  

The *Strike Eagle* aircraft was displayed at the September 1980 
Farnborough air show in the hope of attracting customers.  In the 
meantime, the USAF had begun studying possible concepts for an 
Enhanced Tactical Fighter (ETF) that would replace the General 
Dynamics F-111.  The USAF wanted an aircraft which could conduct the 
strike mission alone, without any need for fighter escort, electronic 
jamming aircraft, or AWACS support.  In the interest of cost 
containment, the Air Force decided to explore the possibility that 
conversions of existing aircraft such as the F-15 or F-16 could meet 
the ETF requirement rather than to try and develop an entirely new 
aircraft.  One of the aircraft initially considered was the Panavia 
Tornado, but it was ruled out fairly early in the game because of its 
short range and its obvious political disadvantage of not being made 
in the USA.  

The ETF studies led to a fly-off competition between the F-15 and the 
cranked arrow-wing F-16XL (sometimes known as the F-16E).  McDonnell 
Douglas provided four Eagles for the flyoff, one of them being the 
*Strike Eagle* demonstrator.  F-15D serial number 80-0055 flew weapons 
separation tests at Eglin AFB.  The *Strike Eagle* demonstrator 
aircraft flew tests at Edwards AFB evaluating the efficiency of the 
Synthetic Aperture Radar.  F-15C serial number 78-0468 flew sorties 
from Edwards AFB to studyfully-instrumented performance and flying 
qualities.  F-15D 81-0063 completed 36 operational evaluation flights 
from Edwards AFB.  General Dynamics provided two cranked arrow-winged 
F-16XLs for the competition.  

The F-15 was named the winner of the Dual-Role Fighter competition on 
February 24, 1984, partly on the basis of cost estimates.  The 
production version of the *Strike Eagle* was designated F-15E.  Full 
scale development of the F-15E began in 1984, with the first 
production F-15E (86-0183) flying on December 11, 1986, with test 
pilot Gary Jennings at the controls.  

The F-15E is externally and dimensionally similar to the two-seat 
F-15D.  However, the F-15E is internally redesigned with a stronger 
structure so that it can safely operate at takeoff weights as great as 
81,000 pounds.  The structure is cleared for 16,000 hours, double the 
lifetime of earlier F-15s.  Space for additional avionics is provided 
at the expense of a slight decrease in internal fuel capacity to 2019 
US gallons.  The entire rear fuselage pod is manufactured from 
superplastic-formed and diffusion- bonded titanium, which results in a 
neater, lighter, and more capacious engine bay.  

The heart of the F-15E's electronics suite is the AN/APG-70 radar.  It 
is intended to be used without being detected by an enemy's air 
defenses.  The radar supposedly can be quickly switched on to obtain 
an single-sweep synthetic aperture radar image of a target area 
located as much as 45 degrees to either side of the aircraft's flight 
path, then rapidly switched off seconds later, making it difficult for 
an enemy to pick up the emissions and track the F-15E's location and 
flight path.  The radar map can be "frozen" on the screen, and updated 
periodically by new sweeps as the aircraft gets nearer to the target.  
The radar display terminals process the radar signals received and can 
provide a bird's eye view of ground targets that are of higher 
resolution and taken from further away than the images produced by 
previous radars.  Roads, bridges, and airfields can be identified as 
far as 100 miles away, and as the F-15E nears the target image 
resolution becomes progressively sharper and smaller targets such as 
trucks, aircraft, and tanks can be distinguished.  

Another key element of the F-15E's weapons delivery system is the 
LANTIRN (which is an acronym standing for Low-Altitude Navigation and 
Targeting, Infra-Red for Night) system, which consists of two pods, 
one carried underneath each air intake.  The starboard pod is used for 
navigation and contains a FLIR (Forward-Looking, Infra-Red) which can 
be used to display a high-quality video image of the oncoming terrain 
on the pilot's heads-up display, enabling high-speed low-level flights 
to be made at night under clear weather conditions.  The navigation 
pod also carries a terrain-following radar which is also effective in 
bad weather.  The pilot can manually respond to cues from the system 
or can couple the system to the flight controls for "hands-off" 
automatic terrain-following flight at altitudes as low as 200 feet off 
the deck.  The port pod is a targeting pod which contains a 
high-resolution tracking FLIR, a missile boresight correlator, and a 
laser designator.  The boresight correlator is used to guide the 
Maverick air-to-surface missile and the laser designator is used for 
weapons such as laser guided bombs that home in on reflected laser 
light.  

Front and rear cockpits are upgraded with multi-purpose cathode ray 
tube displays for improved navigation, weapons delivery, and systems 
operations.  The pilot's cockpit has redesigned controls, a wide field 
of vision heads-up display, and three cathode ray tubes which provide 
multi-purpose displays of navigation, weapons delivery, and systems 
operations.  The rear-cockpit weapons system officer has four cathode 
ray terminals for radar, weapons selection, and monitoring of enemy 
tracking systems.  

The WSO has at his disposal an updated ALQ-135 electronic warfare 
system which features a new broadband jammer.  The antennae for this 
system are located at the trailing edge root of the left horizontal 
atablizer and in the leading edge roots of both wings.  This replaces 
the blade antennae located under the nose of the A, B, C, and C 
versions.  

The F-15E retains the conformal fuel tank of the F-15D.  The 
air-to-ground weapons load is raised to a maximum of 23,500 pounds by 
adding six tangential stubs on the corner of each conformal fuel tank 
for the carriage of external ordnance.  The F-15E retains the 20-mm 
M61A1 cannon of the F-15D, although the ammunition capacity is reduced 
to 512 rounds.  However, the F-15E retains the full air-to-air 
capability of the F-15D version, and can carry AIM-7M Sparrow 
medium-range missiles on the conformal fuel tank stubs and AIM-9M 
Sidewinder short-range missiles on the underwing pylons.  

The F-15E is powered by the F-15C/D's pair of 24,000 lb.s.t.  
afterburning Pratt & Whitney F100-PW-220 turbofans.  However, the 
engine bays were adapted so that these engines could eventually be 
replaced by more powerful turbofans in the 30,000 pound thrust class.  
Plans to deliver F-15Es with the twenty-percent more powerful 
F100-PW-229 engine beginning in August 1991 were delayed slightly.  
However, the -229 turbofans were duly installed in succeeding F-15Es.  

In June 1990, the F-15E experienced its first competition with other 
aircraft in the USAF's *Long Rifle* gunnery meet.  It scored first and 
second in the contest.  

The low-altitude ride in the F-15E can be quite a bit rougher than 
that in the F-111 because of the lower wing loading and the higher 
gust response.  The F-15E is better in diving attacks and low-level 
high-speed dash than it is in sustained low-level high speed flight.  
High-speed weapons separations trials performed at low level over the 
Nevada desert where vicious thermals are common, provided some crew 
discomfort.  However, the accuracy and precision of the delivery of 
weapons in all-weather conditions was excellent.  

Following completion of operational test and evaluation at Edwards AFB 
and *Seek Eagle* weapons carriage and separation tests carried out at 
Eglin AFB, F-15Es were first delivered to the 425th TFTS, 405th TTW at 
Luke AFB for crew training.  The first operational F-15E squadron was 
the 336th TFS, 4th TFW at Semour Johnson AFB in North Carolina, which 
received its first planes in early 1989.  Limited operational 
capability was obtained with the F-15E in October 1989, with full 
operational capability being projected for August 1990.  

Integration of the LANTIRN system with the APG-70 radar proved to be 
much more difficult than expected, and the F-15E was still not fully 
compat-ready by the time of *Desert Storm*.  The F-15E had only just 
begun to operate with the LANTIRN navigation pod and did not yet have 
the system's targeting pod, so it was at least temporarily capable of 
delivering only "dumb" bombs.  Although the F-15E was still not fully 
combat-ready, 48 F-15Es flew in the Gulf War.  F-15Es joined other 
Coalition aircraft in searching for and attacking Iraqi "Scud" missile 
launchers.  These Scud hunt missions were largely unsuccessful, but 
the F-15Es attacked many other Iraqi targets of opportunity.  Most of 
these sorties were flown at medium altitudes, and the F-15E did not 
get much of a chance to demonstrate its low-level capabilities.  The 
full LANTIRN system was not available until near the end of the Gulf 
War, and even then the targeting pod still experienced problems and 
was not employed in combat to its full capability.  Although only some 
of the F-15Es were equipped with their LANTIRN targeting pods by the 
end of the Gulf War, pilots claimed that 80 percent of the 
laser-guided bombs dropped by F-15Es hit their targets.  

Wartime experience with the F-15E was handed on to the F-15 Combined 
Test Force (CTF) at Edwards AFB, which is doing work on F-15E engine, 
software, radar, weapons, and LANTIRN development.  Even after the 
Gulf War was over, work still had to be done to clear the F-15E for 
the full set of weapons it could carry, including the Mk 20 Rockeye 
and CBU-87 cluster bombs, Mk-82 and Mk-84 500-lb and 1000-lb bombs, 
AGM-65 Maverick missiles, and GBU-10 and GBU-15 laser-guided weapons.  

The 200th and last F-15E was delivered to the USAF in June of 1994.  
However, the Royal Saudi Air Force has ordered a batch of 72 F-15Es, 
scheduled for delivery in 1997-1998.  If this order is allowed to 
stand, the Eagle production line at St Louis will be in business until 
the end of the century.  

In mid 1994, there was a prolonged grounding of many F-15Es because of 
problems with their F100-PW-229 engines.  The problem seems to be with 
stress-related cracking of the engine's fourth-stage turbine blades.  
This affects 75 F-5Es at Elmendorf AFB, RAF Lakenheath, and Lellis 
AFB.  


71-0291			McDonnell Douglas F-15B-4-MC Eagle
				Used for evaluation of FAST Pack conformal
				fuel tanks and LANTIRN pod.  Also became
				development aircraft for F-15E Strike Eagle
86-0183/0184		McDonnell Douglas F-15E-41-MC Eagle
86-0185/0190		McDonnell Douglas F-15E-42-MC Eagle
87-0169/0189		McDonnell Douglas F-15E-43-MC Eagle
87-0190/0210		McDonnell Douglas F-15E-44-MC Eagle
87-0211/0216		cancelled contract for McDonnell Douglas F-15E
88-1667/1687		McDonnell Douglas F-15E-45-MC Eagle
88-1688/1708		McDonnell Douglas F-15E-45-MC Eagle
89-0471/0506		McDonnell Douglas F-15E Eagle
90-0227/0262		McDonnell Douglas F-15E Eagle
91-0300/0335		McDonnell Douglas F-15E Eagle 
92-0607/0608 		McDonnell Douglas F-15E Eagle
 



Specification of McDonnell Douglas F-15E Eagle:  

Two Pratt & Whitney F100-PW-229 turbofans, each rated at 17,800 
lb.s.t. dry and 29,100 lb.s.t. with afterburning.  
Performance:  Maximum speed Mach 2.54 (1676 mph) at 40,000 feet 
(short-endurance dash), Mach 2.3 (1520 mph) (sustained). Maximum 
combat radius 790 miles.  Maximum ferry range 2765 miles.  
Weights:  31,700 pounds empty, 81,000 pounds maximum takeoff.  
Dimensions:  wingspan 42 feet 9 3/4 inches, length 63 feet 9 inches, 
height 18 feet 5 1/2 inches, wing area 608 square feet.  
Armament:  One 20-mm M61A1 rotary cannon with 512 rounds.  A maximum 
ordnance load of 24,500 pounds can be carried on the centerline and 
two underwing stations plus four tangential carriers attached to the 
conformal fuel tanks.  In the air-to-air mission, up to four AIM-9L/M 
Sidewinders can be carried on the underwing stations and four AIM-7F/M 
Sparrow missiles can be carried on the conformal fuel tank 
attachments.  Alternatively, up to eight AIM-120 AMRAAM missiles can 
be carried.  

Sources:

   McDonnell Douglas Aircraft Since 1920, volume II, Rene J.
   Francillon, Naval Institute Press, 1990.

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

   Combat Aircraft F-15, Michael J. Gething and Paul Crickmore,
   Crescent Books, 1992.
   
   The American Fighter, Enzo Angelucci and Peter Bowers, 
   Orion, 1987.

   The World's Great Interceptor Aircraft, Gallery Books, 1989. 

   F-15 Eagle, Robert F. Dorr, World Airpower Journal, Volume 9,
   Summer 1992.

Joe Baugher			  **************************************
AT&T Bell Laboratories		  *  "Why are you here, Q?  Have you   *
1000 E. Warrenville Road	  *  been banished from the            *
Room 1N 308			  *  Continuum AGAIN?"                 * 
P. O. Box 3013			  *  	      Capt Jean-Luc Picard     *
Naperville, Illinois 60566-7013	  *              ST-TNG		       *
USA				  **************************************
Phone: (708) 713 4548
jfb@uscbu.ih.att.com
			    Who, me?  Speak for AT&T?  Surely you jest!	






