McDonnell F-15A Eagle

Last revised February 20, 2000


The F-15A was the first production version of the Eagle. There was no XF-15, since the aircraft had been ordered "off the drawing board", with no prototypes being built. A total of 384 single-seat F-15A were built, including 18 Full-Scale Development (FSD) aircraft.

The initial F-15 contract called for 20 FSD aircraft--a preliminary batch of 10 single-seat F-15A (71-0280/0289) and two TF-15A two-seat (71-0290 and 71-0291) Category I versions, plus eight Category II FSD aircraft, all of them in F-15A single-seat form (72-0113/0120). Category I flight tests are carried out with the manufacturer's test pilots. Category II testing involves flight testing by a USAF joint test force consisting of pilots from Air Systems Command and the Tactical Air Command. Category III testing is the follow-on operational test and evaluation program carried out by units in the field.

One of the more unusual aspects of the Eagle development program was the use of large 3/8-scale glider models of the F-15 which were dropped from an NASA-operated NB-52B (52-0008) at the NASA Dryden Flight Research Center. The models were made of aluminum, wood, and fiberglas. They weighed 2425 pounds each and were 23 feet long. During the drops, the models were under radio control from the ground, and were directed through high angle of attack, stalling, and spinning maneuvers. At the end of the flights, the models deployed a parachute and were recovered in midair by a helicopter.

The first F-15A (sometimes called YF-15A, with the Y-prefix indicating service-test duties), serial number 71-0280, was rolled out in a ceremony at St Louis on June 26, 1972. It was dismantled, loaded aboard a C-5A, and transported out to Edwards AFB in California. It made its first flight there on July 27, 1972, company test pilot Irving Burrows being at the controls.

The first 10 single-seat Eagles were allocated to Category I of the test program. Each of the planes was allocated to a specific task in the flight test program, as follows:

Serial First Flight Function 71-280 July 27, 1972 Open the flight envelope, explore handling qualities, check out external stores carriage. 72-281 September 28, 1972 Tests of F100 engine 72-282 November 4, 1972 Avionics development, calibrated air speed tests. First to be equipped with APG-63 radar. 72-283 January 12, 1973 Flying structural test airframe 72-284 March 7, 1973 First F-15 to be equipped with the M61A1 cannon. Internal gun, external fuel jettison and armament tests. 72-285 May 23, 1973 Second avionics test aircraft. Avionics tests, flight control evaluation, missile fire control. 72-286 June 14, 1973 Armament and external fuel stores tests 72-287 August 25, 1973 Spin recovery, high angle of attack, and fuel system tests. 72-288 October 20, 1973 Integrated aircraft/engine performance tests. 71-289 January 16, 1974 Tactical electronic warfare system, radar and avionics evaluation.

Some of the 12 Category I test aircraft were later delivered to the Air Force.

By October 29, 1973, 11 of the 12 Category I Eagles had flown, and a maximum speed of Mach 2.3 and an altitude of 60,000 feet had been reached. Remarkably, very few problems were encountered during flight testing. However, early in the test program, problems were encountered with buffeting and wing loading problems at certain altitudes. The solution to the problem was found to be the removal of four square feet in wing area diagonally from the wing tip, giving the Eagle its characteristic raked wingtips. A flutter problem discovered during wind tunnel testing required that a dogtooth be cut into the leading edge of the horizontal tail. The dorsal airbrake was found to cause excessive buffeting when it was in the fully-open position, and it was found necessary to increase its area from 20 to 31 square feet so that the required drag could be achieved with lower extension angles.

Production of an initial batch of 30 F-15A/B fighters was announced on March 1973. The first Eagle to be delivered to an operational USAF unit was TF-15A 73-0108, formally accepted by the 555th Tactical Fighter Training Squadron of the 58th Tactical Training Wing at Luke AFB, Arizona on November 4, 1974 in a ceremony presided over by President Gerald Ford. This wing served as the Replacement Training Unit (RTU) for F-15 operations during the initial phases of the introduction of the Eagle into service.

During the winter of 1974-75, McDonnell modified F-15A serial number 72-0119 in an attempt to set world time-to-climb records. The project was given the name Operation Streak Eagle. In an effort to save weight, all non-mission critical systems were deleted, including the flap and the speed brake, the armament, the radar, and the fire control system. The paint was even stripped off, leaving a bare metal aircraft. It weighed 1800 pounds less than the stock F-15A. The record attempts were carried out during the winter at Grand Forks AFB in North Dakota to take advantage of the cold temperatures. During the record attempts, only enough fuel was carried to make the specific flight and return to base. The aircraft broke eight existing time-to-climb records previously held by the F-4B and the MiG-25:

Altitude Time Date Pilot 3000 meters 27.57 sec January 16, 1975 Maj. R. Smith 6000 meters 39.33 sec January 16, 1975 Maj W. R. Macfarlane 9000 meters 48.86 sec January 16, 1975 Maj W. R. Macfarlane 12,000 meters 59.38 sec January 16, 1975 Maj W. R. Macfarlane 15,000 meters 77.02 sec January 16, 1975 Maj D. W. Peterson 20,000 meters 122.94 sec January 19, 1975 Maj R. Smith 25,000 meters 161.02 sec January 26, 1975 Maj D. W. Peterson 30,000 meters 207.80 sec February 1, 1975 Maj R. Smith

The Streak Eagle aircraft is now on outdoor display at the USAF Museum at Wright Patterson AFB at Dayton, Ohio. Most of these records were later broken by the Soviet "P-42", which was a prototype for the Sukhoi Su-27 interceptor.

Production of an initial batch of 30 F-15A/B fighters was announced on March 1973. The first Eagle to be delivered to an operational USAF unit was TF-15A 73-0108, formally accepted by the 555th Tactical Fighter Training Squadron of the 58th Tactical Training Wing at Luke AFB, Arizona, on November 4, 1974 in a ceremony presided over by President Gerald Ford. This wing served as the Replacement Training Unit (RTU) for F-15 operations during the initial phases of the introduction of the Eagle into service.

Deliveries to the first combat-ready wing, the 1st TFW at Langley AFB in Virginia, began in January 1976. The F-15s replaced the F-4Es that had previously been flown by this wing. In 1977, F-15As and Bs were issued to the 36th Tactical Fighter Wing based at Bitburg, Germany, marking the first overseas deployment of the Eagle. That same year, the 49th TFW at Holloman AFB in New Mexico, began to receive the Eagle. The 57th Fighter Weapons Wing at Nellis AFB, Nevada received its first F-15A/B Eagles in 1977. These were issued to the 433rd Fighter Weapons Wing and were used to train pilots destined for new Eagle squadrons.

In 1978, Eagles went to the 32nd Tactical Fighter Squadron based at Soesterberg in the Netherlands. The 32nd TFS was under Dutch Air Force control as part of its NATO mission. That same year, the 33rd TFW at Eglin AFB in Florida received F-15A/B Eagles.

The introduction of the F-15 into USAF service was not without its problems. The pilots at Luke AFB with the Tactical Training Wing found that they could not mount the planned number of sorties. There were difficulties with parts and maintenance, but the most serious problem was with the engines. The Air Force had underestimated the number of powercycles per sortie and had not realized how much the Eagle's maneuvering capabilities would result in frequent abrupt changes in throttle setting. This caused unexpectedly high wear on key engine components, resulting in frequent failures of key engine components such as first-stage turbine blades. These problems could be corrected by more careful maintenance and closer attention to quality control during manufacturing of engine components. However, the most serious problem was stagnation stalling.

There were frequent groundings and delays in engine deliveries while an attempt was made to fix these problem. Strikes at two major subcontractors delayed the delivery of engines. By the end of 1979, the USAF was forced to accept engineless F-15 airframes and place them in storage until sufficient numbers of engines could be delivered. A massive effort by Pratt & Whitney helped to alleviate this problem, but the F-15 suffered from an engine shortage for a long time.

Early problems with the reliability of F100 engines were largely overcome by modifications plus improvements in materials, maintenance and operating procedures. The installation of a quartz window in the side of the afterburner assembly to enable a flame sensor to monitor the pilot flame of the augmentor helped to cure the problem with "hard" afterburner starts. Modifications to the fuel control system helped to lower the frequency of stagnation stalls. In 1976 the F-15 fleet had suffered 11-12 stagnation stalls per 1000 flying hours. By the end of 1981, this rate was down to 1.5. However, the F100 even today still has a reputation of being a temperamental engine under certain conditions.

In the mid-1980s, the 21st Composite Wing (later Tactical Fighter Wing) received F-15A/B Eagles. There was an embarrassing incident on March 19, 1990, when a pilot of one of the Wing's F-15s accidentally fired a live Sidewinder round which struck and damaged another F-15. This incident caused the commander of the Wing to be relieved, although the damaged aircraft was able to land safely, emphasizing the high degree of structural strength and survivability that had been built into the F-15 design.

The last of the 360 F-15As and Bs that were built were delivered to fighter interceptor squadrons that had been assigned by the Tactical Air Command to the aerial defense of the United States. This organization was a descendant of the now-defunct Air Defense Command (known in its last years as the Aerospace Defense Command), which had turned over its resources to TAC in October of 1979. TAC reorganized these assets into the Air Defense Tactical Air Command (ADTAC), headquartered at Colorado Springs. The headquarters were later moved to Langley AFB. A further organization change in 1985 resulted in ADTAC becoming the First Air Force. Four TAC squadrons (5th, 48th, 57th, and 318th Fighter Interceptor Squadrons) took the F-15A/B on charge in the interceptor role, replacing the Convair F-106 Delta Dart. Some of the Eagles operated by these squadrons were wired to carry the Vought antisatellite weapon, although the ASAT program had been officially dropped at Congressional insistence in the early 1980s. The role of the Eagle in the air defense of the United States was a brief one, with the bulk of the air defense role now being carried out by the F-16A Fighting Falcon. The First Air Force's Eagle interceptor squadrons were deactivated during the early 1990s, and their planes were passed along to the Air National Guard.

A Multi-Stage Improvement Program (MSIP) was developed in 1982 for the F-15A/B, which would have operated in parallel with that of the MSIP for the F-15C/D (which was known as MSIP II). However, the MSIP for the the F-15A/B was cancelled because it was deemed too costly. Subsequently, it was decided that it was worthwile to upgrade those F-15A/Bs that were still in good condition with portions of the MSIP II designed for the F-15C/D. Under this partial MSIP, the APG-70 radar of the F-15C was not fitted, but the improved ECM suite and some cockpit changes were applied. The F100-PW-100 engines have been raised to -220E standard, being rougly equivilant to the -220s of the F-15C/D. In 1997, an F-15 test bed flew with an upgraded APG-63(V)1 as a replacement for the APG-63 radar. The APG-63(V)1 uses some portions of the APG-70 of the F-15C/C and gives a much better speed and reliability as compared to the APG-63.

Those early A/B aircraft not deemed worthy of going through MSIP have been placed in storage at AMARC, sent to Israel for use as spares sources, or are about to be retired.

Serials of F-15A Eagle:

71-280/281		McDonnell Douglas F-15A-1-MC Eagle
				281 bailed to NASA in 1975.  Returned
				to USAF in 1983, now on display at Langley AFB
71-282/284		McDonnell Douglas F-15A-2-MC Eagle
				0284 to GF-15A
71-285/286		McDonnell Douglas F-15A-3-MC Eagle
				0286 to GF-15A
71-287/289		McDonnell Douglas F-15A-4-MC Eagle
				0287 bailed to NASA in 1976 as 835
72-113/116		McDonnell F-15A-5-MC Eagle
 				0116 delivered to Israel, Peace Fox I
72-117/120		McDonnell F-15A-6-MC Eagle
				0117,0118 delivered to Israel, Peace Fox I
				0119 set 8 world time-to-height records as
				part of Operation Streak Eagle - This plane is 
				on display at WPAFB Museum.
				0210 delivered to Israel, Peace Fox I
73-085/089		McDonnell Douglas F-15A-7-MC Eagle
73-090/097		McDonnell Douglas F-15A-8-MC Eagle
73-098/107		McDonnell Douglas F-15A-9-MC Eagle
74-081/093		McDonnell Douglas F-15A-10-MC Eagle
74-094/111		McDonnell Douglas F-15A-11-MC Eagle
74-112/136		McDonnell Douglas F-15A-12-MC Eagle
74-143/157		cancelled contract for McDonnell Douglas F-15A/B Eagle
75-018/048		McDonnell Douglas F-15A-13-MC Eagle
75-049/079		McDonnell Douglas F-15A-14-MC Eagle
75-090/124		cancelled contract for McDonnell Douglas F-15A/B Eagle
76-008/046		McDonnell Douglas F-15A-15-MC Eagle
76-047/083		McDonnell Douglas F-15A-16-MC Eagle
76-084/113		McDonnell Douglas F-15A-17-MC Eagle
				0086 used for trials with Vought ASM-135A
				ASAT.
76-114/120		McDonnell Douglas F-15A-18-MC Eagle
				0120 delivered to Israel
76-121/123		cancelled contract for McDonnell Douglas F-15A Eagle
76-1505/1514		McDonnell Douglas F-15A-17-MC Eagle 
				For Israel, Peace Fox II
76-1515/1523		McDonnell Douglas F-15A-18-MC Eagle 
				For Israel, Peace Fox II
77-061/084 		McDonnell Douglas F-15A-18-MC Eagle
				0084 used as test bed for APG-63 radar
77-085/119 		McDonnell Douglas F-15A-19-MC Eagle
77-120/153 		McDonnell Douglas F-15A-20-MC Eagle

Specification of McDonnell Douglas F-15A Eagle:

Engines: Two Pratt & Whitney F100-PW-100 (JTF22A-25A) axial-flow turbofans, each rated at 12,420 pounds dry, 14,670 pounds at full military power, and 23,830 pounds with afterburning.. Maximum speed: 1650 mph (Mach 2.5) at 36,000 feet, 915 mph at sea level. Cruising speed 570 mph. Initial climb rate 40,000 feet per minute. Service ceiling 65,000 feet. Maximum unrefuelled range 3450 miles. Dimensions: wingspan 42 feet 9 1/2 inches, length 63 feet 9 inches, height 18 feet 5 1/2 inches, wing area 608 square feet. Weights: 27,000 pounds empty, 40,000 pounds combat, 41,500 pounds gross, 66,000 pounds maximum takeoff. Fuel: Maximum internal fuel 1790 US gallons. Three 610-gallon drop tanks can be carried, one on the fuselage centerline and one on each of the underwing pylons, bringing total fuel capacity to 3620 US gallons. Armament: One 20-mm General Electric M61A1 Vulcan cannon n the starboard wing root with 940 rounds. Provision for four AIM-7F/M Sparrow missiles on hardpoints attached to the lower outer edges of the air intake trunks, two on each side. Four AIM-9 Sidewinders infrared-homing missiles are carried on the underwing pylons, two on each side.

Sources:


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

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

  3. Combat Aircraft F-15, Michael J. Gething and Paul Crickmore, Crescent Books, 1992.

  4. The American Fighter, Enzo Angelucci and Peter Bowers, Orion, 1987.

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

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

  7. Boeing/McDonell Douglas F-15 Eagle Variant Briefing, John D. Gresham, World Air Power Journal, Vol 33, Summer 1998.