Subject: Fighter Series--Northrop F-5 (1 of 11)

From: [email-masked]
Date: 25 Jul 94 16:52:34 GMT

>From [email-masked]

The development of the Northrop F-5 began as far back as 1954, when a 
Northrop team toured Europe and Asia to examine the defense needs of 
NATO and SEATO countries.  The result of the tour was a 1955 company 
design study for a lightweight supersonic fighter that would be 
relatively inexpensive, easy to maintain, and capable of operating out 
of short runways and secondary airstrips as well as from small 
aircraft carriers.  The powerplant was to be the General Electric J85 
turbojet, which had originally been intended as a powerplant for the
GAM-72 Green Quail decoy drone.  

The proposal was given the company designation N-156F.  At the same 
time, a two-seat advanced trainer version was also proposed under the 
designation N-156T.  Both versions were to be powered by a pair of 
General Electric J85 turbojets grouped closely together in the rear 
fuselage and fed by a pair of lateral air intakes on the sides of the 
lower fuselage.  The very thin wings had leading edge slats and 
trailing edge flaps, and the all-flying horizontal tail was mounted 
low on the fuselage underneath the engines.  The fuselage was designed 
according to the Area Rule, with the cross section of the fuselage 
being narrowed in the region of the wing to present a nearly constant
total cross-section area to the airflow passing over the aircraft.

The Navy turned down the Northrop proposal, since it had already 
decided to take its small aircraft carriers out of service.  The Air 
Force did not initially look favorably upon the proposal either, since 
it perceived no need for a lightweight fighter.  However, it did need a 
new trainer to replace the Lockheed T-33, and in June of 1956 the
Air Force announced that it was going to acquire the N-156T trainer
version under the designation T-38.  The name *Talon* was chosen.

Undaunted, the Northrop company decided on February 25, 1958 to 
proceed with the development of the N-156F as a private venture.  
The N-156F drew heavily on the design of the N-156T (T-38).  The
low-mounted wing had no dihedral or incidence, and was sweptback at 
quarter-chord by 24 degrees.  The N-156F wing differed from that of
the T-38 in having a forward-angled fillet or leading-edge extension
(LEX) at each root.  The removable wingtip tanks were area-ruled, a 
rather unusual feature for the time.  Hydraulically-powered sealed-gap 
ailerons were provided at approximately mid-span, with light alloy 
single-slotted flaps inboard.  The leading edge was provided with 
continuous-hinge flaps of full-depth honeycomb construction.  
Armament was to have consisted of two 20-mm M39 cannon in the upper
nose plus a AIM-9 Sidewinder missile at each wingtip.  Additional
offensive loads could be carried underneath a centerline pylon
and on two underwing stores stations.

The mockup was inspected by the Air Force early in 1958.  In the meantime,
the Air Force had studied the N-156F in greater depth and had come
to recognize that the fighter proposal had great promise as a low-cost 
fighter for many of America's allies who could not possibly hope to 
afford the expensive interceptors that were at that time entering USAF 
service.  In May of 1958, the Air Force ordered three prototypes from 
Northrop under the company designation N-156T and to be called 
*Freedom Fighter*.  The USAF serials were 59-4987/4989.  In addition, one
static test airframe (59-4993) was ordered. 

In early 1959, Northrop management began discussions with overseas
manufacturers who might be interested in license production of the 
N-156F.  Companies approached included SABCA of Belgium, Fokker of
Holland, and Fiat of Italy.  Talks also took place with Austrialia and
with Fairey Aviation of the UK.  Northrop's president stated that
he anticipated the potential worldwide market for the N-156F to be
4000 aircraft!  As it turned out, these European companies turned
down Northrop's overtures, and opted instead to build the Lockheed
F-104 Starfighter.  

Undaunted, Northrop pressed onward with its private venture. As it
turned, license production arrangements were later to be worked out
with Canadair of Canada, with CASA of Spain, with FFA of Switzerland,
with Hanjin of South Korea, and with AIDC of Taiwan.

The first N-156F (59-4987) was built in just over a year.  It was 
initially powered by a pair of non-afterburning General Electric 
YJ85-GE-1 turbojets rated at 2100 lb.s.t. each.  It took off on its first 
flight on July 30, 1959, test pilot Lew Nelson being at the controls.  
The cannon armament was not fitted at the time of the first flight.

The non-afterburning turbojets were soon replaced by production-type 
J85-GE-5s, each rated at 2500 lb.s.t. dry and 3850 lb.s.t. with 
afterburning.  The second N-156F (59-4988) soon joined the flight test 
program, but the third N-156F (59-4989) was shelved before completion,  
pending the decision by the Defense Department on whether the N-156F
merited a production contract. 

In early 1962, the first prototype was tested by the US Army as a
possible candidate to meet an Army requirement for a fixed-wing
close support aircraft.  Other contenders for the Army contract were
the Fiat G-91 and the Douglas A4D Skyhawk.  The prototype was
painted in Army markings for the tests.  Although Army pilots were
impressed with the N-156F, the Defense Department decided not to
allow the Army to acquire fixed-wing close support aircraft, 
restricting the service to operating only helicopters for this role. 

On April 25, 1962, the Department of Defense announced that it had 
chosen the N-156F for its Military Assistance Program (MAP).  
America's NATO and SEATO allies would now be able to acquire a 
supersonic warplane of world-class quality at a reasonable cost.  The 
USAF was to act as the purchasing agency for the program and was put 
in charge of crew training.  The planes were to carry USAF serial 
numbers for record-keeping purposes.  On August 9, 1962, the Model 
N-156F was given the official designation of F-5A and was given the 
official name *Freedom Fighter*.  At the same time, a two-seat combat 
trainer version was ordered under the designation F-5B.  It was to 
retain the full combat capability of the F-5A.  

The original configuration of the F-5A provided for only minimal 
fighter capability.  Following approval of the F-5A project, the 
Defense Department called for the addition of two internal 20-mm 
cannon and provision for nose fuel tanks and cameras.  In addition, 
trials with the first two prototypes had indicated the need for a 
stronger wing structure that could accommodate an additional stores 
station underneath each wing and a stronger undercarriage to 
accommodate the added load.  It was expected that up to 6200 pounds of 
ordnance could be carried on four underwing pylons and one under- 
fuselage pylon.  

These changes were built into the third N-156F (59-4989), which became 
in effect the first production F-5A.  At the same time, uprated 
J85-GE-13 turbojets were fitted, each offering 3050 lb.s.t. dry and 
4080 lb.s.t. with afterburning.  59-4989 took off on its maiden 
flight on July 31, 1963 with Hank Chouteau at the controls.  The first 
and second prototypes were subsequently brought up to F-5A production 
standards.  

An initial production contract for 71 F-5s was awarded on October 22, 
1962, and a further contract for 99 was awarded on August 27, 1963.   
About 1 out of 9 of these machines were to have been two-seat F-5Bs.
Each plane was to have cost about $600,000, with the bill being
paid partially or wholly by the US government under the provisions
of MAP.  A production rate of twelve F-5s per month was to be
attained by the end of 1964, with first deliveries taking place early
in 1965.  

The first two genuine production F-5As (63-8367 and -8368) joined the 
test program at the end of 1963.  Initial deliveries, beginning in 
April of 1964, were to the 4441st Combat Crew Training Squadron based 
at Williams AFB in Arizona, where the USAF trained the pilots and 
maintenance personnel of nations receiving F-5s.  This base acted as 
the instructional center for foreign personnel who were to act as 
instructors on the F-5 in their own countries.  

The F-5A is optimized for the air-to-ground role and has only a very 
limited air-to-air capability.  In the interest of achieving low cost, 
the F-5A was not equipped with a fire-control radar, the weapons being 
aimed by a simple optical sight acting in conjunction with a small 
Emerson radar ranging set installed in the extreme nose.  The initial 
avionics fit was rather austere, the standard electronic equipment 
including an AN/ARC-34C UHF radio, PP-2024 SWIA Missile AVX, AN/AIC-18 
interphone, J-4 compass, AN/APX-46 IFF and AN/ARN-65 Tacan receiver.  

The F-5A has very docile handling attributes.  It is almost 
unspinnable, and exhibits little, if any, wing drop at the stall.  By 
grouping the two J85 engines so closely together, Northrop has greatly 
reduced engine-out asymmetric effects.  

Production of the F-5A by Northrop ended in June of 1972, after 617 
examples had been manufactured.  

Serial numbers of F-5A Freedom Fighter:

59-4987/4989		Northrop YF-5A-NO Freedom Fighter
59-4993			Northrop XF-5A static airframe c/n N6000 
63-8367/8437		Northrop F-5A-15-NO Freedom Fighter
64-13306/13376		Northrop F-5A-20-NO Freedom Fighter
64-13389/13408		Northrop F-5A/B Freedom Fighter - cancelled contract
65-10476/10581		Northrop F-5A-25-NO Freedom Fighter
66-8405/8515		Northrop F-5A Freedom Fighter - cancelled contract
66-9119/9229		Northrop F-5A-30-NO
66-14457/14466		Northrop F-5A-30-NO
67-14775		Northrop F-5A Freedom Fighter - cancelled contract
67-14894/14905 		Northrop F-5A-35-NO Freedom Fighter
67-21153/21218		Northrop F-5A-35-NO Freedom Fighter
67-21236/21258		Northrop F-5A-35-NO Freedom Fighter
67-21259/21271		cancelled contract for Northrop F-5A Freedom Fighter
67-22548/22555		Northrop F-5A-35-NO Freedom Fighter
68-9043/9085		Northrop F-5A-40-NO Freedom Fighter
69-6462/6483		Northrop F-5A Freedom Fighter - contract cancelled
69-7091/7134  		Northrop F-5A-45-NO Freedom Fighter
69-7174/7177  		Northrop F-5A-45-NO Freedom Fighter 
70-1373/1407		Northrop F-5A-50-NO Freedom Fighter
71-0260/0276		Northrop F-5A-55-NO Freedom Fighter
71-1276/1317		Northrop F-5A-NO Freedom Fighter
71-1377/1390		Northrop F-5A-55-NO Freedom Fighter  

Specification of Northrop F-5A Freedom Fighter: 

Two General Electric J85-GE-13 turbojets, rated at 2720 lb.s.t., 4080 
lb.s.t. with afterburning.  Maximum speed: 925 mph (Mach 1.4) at 
36,000 feet.  Maximum cruising speed without afterburning: 640 mph 
(Mach 0.97) at 36,000 feet.  Stalling speed 147 mph with flaps 
extended.  Initial climb rate 30,400 feet per minute.  Service 
ceiling: 50,500 feet.  Takeoff run: 2650 feet with two Sidewinder 
missiles.  Landing run from 50 feet with braking parachute was 3900 
feet.  Range with maximum fuel was 1387 miles.  Combat radius with 
maximum payload 195 miles.  Combat radius with maximum fuel and two 
530-pound bombs 558 miles.  Two internal fuel tanks composed of 
integral cells with total usable capacity of 583 US gallons.  One 150 
US gallon drop tank could be carried on the fuselage centerline pylon, 
two 150 US gallon droptanks could be carried underneath the underwing 
pylons, and a 50-gallon tank could be carried at each wingtip, 
bringing total fuel capacity to 1133 US gallons.  
Dimensions: wingspan 25 feet 3 inches, length 47 feet 2 inches, height 
13 feet 2 inches, wing area 170 square feet.  
Weights: 8085 pounds empty, 11,477 pounds combat, 13,433 pounds gross, 
20,677 pounds maximum takeoff.  
Armed with two 20-mm cannon in the fuselage nose.  Two AIM-9 
Sidewinder missiles could be carried at the wingtips.  Five pylons, 
one under the fuselage centerline and four under the wings that can 
carry up to 6200 pounds of ordinance or fuel tanks.  A 2000-pound bomb 
or a gun pack can be carried from the centerline pylon.  Underwing 
loads can include four air-to-air missiles, Bullpup air-to-surface 
missiles, bombs, up to 20 unguided rockets, bun packs, or external 
fuel tanks.  

Sources:

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

  Jane's American Fighting Aircraft of the 20th Centry, Michael J.H.
  Taylor, mallard Press

  The World's Fighting Planes, William Green, Doubleday, 1964.

  Modern Air Combat, Bill Gunston and Mike Spick, Crescent, 1983.

  United States Military Aircraft Since 1909, Gordon Swanborough and
  Peter M. Bowers, Smithsonian, 1989.

  Post-World War II Fighters: 1945-1973, Marcelle Size Knaac,
  Office of Air Force History, 1986.

  The World Guide to Combat Planes, William Green, Macdonald, 1966. 

  Fighters of the United States Air Force, Robert F. Dorr and
  David Donald, Temple Press/Aerospace, 1990

  The World's Great Attack Aircraft, Gallery, 1988.

  Northrop F-5/F-20, Jerry Scutts, Ian Allan Ltd, 1986.

Joe Baugher				AT&T Bell Laboratories
1000 E. Warrenville Road		Naperville, Illinois 60566-7013