Northrop’s YF-17 Lightweight Fighter

October 27th, 2007
Raul Colon
PO Box 29754
Rio Piedras, Puerto Rico 00929

Throughout its military aviation history, the United States had fielded some of the most advanced fighters in the world. They also have been some of the heaviest planes ever. When the United States entered the Korean War in the 1950s, they were surprised by the advances of the Soviet Union’s fighter planes. The new Mig fighters were lightweight and more manoeuvrable than their US counterparts. Only the skills and training of the US Air Force pilots, not their aircraft, provided America with air dominance over the Korean sky.

As the war progressed, the US became more worried about a perceived Soviet advantage in fighter design. As a result, the Lockheed Company began a crash coarse in the design and development of the next generation US fighter, a fighter so advanced that it could had ruled the skies for two decades. The result of this massive effort was the F-104 Starfighter. Although the F-104 was conceived to be America’s primary air superiority fighter, the Air Force fiddles with the original design specifications and made the aircraft a fighter-bomber. The F-104, beside its main objective of achieving air dominance over the projected battlefield, was also designed to carry nuclear ordinance. Thus the aircraft never achieved its pre-design objective. The US next successful, true air superiority fighter would be the F-4 Phantom. The F-4 proved itself over the skies in South-eastern Asia.

Duelling with Mig fighters it proved the worth of its design. By the mid 1960s, the US Air Force again, worried about the nimbleness of Soviet fighter planes, and in the midst of a generational change on its top brass structure; the old bomber-supporter generals were being pushed out from mid to upper level positions and replaced by fighter planes supporting majors and generals. It was at this time that the Air Force, pushed by the new “fighter establishment”, decided to commence a brand new fighter program. The programme would stress the reduction in weight and the manoeuvrability of aircraft above the multi-role profile that had dominated US recent fighter development. This program would lead to the design and eventual development of America’s first true lightweight fighter of the modern jet age: the F-16 Fighting Falcon.

Since late 1966, the Northrop Corporation had been developing an aircraft that would fit the Air Force’s new specification requirements. Its first major design breakthrough was the P-530, codename Cobra. Although the design never made it past a mock-up project, the P-530 possessed many of the attributes, both avionics packages and aerodynamics characteristics that were to dominate post-Vietnam era fighter development in the United States. Armed with this revolutionary design, Northrop entered the Air Force’s competition for America’s next generation fighter development program in the early 1970s. Based on massive amount of data collected during Northrop’s designer Lee Begin’s research into lightweight fighter platforms and the on the mock-up project P-530; Northrop began the design of a new type of aircraft. The YF-17 project was born. The YF program was Northrop’s entry into what was later refer to as the “The Deal of the Century”. The “Deal” pitted the YF-17 platform against the FY-16 design.

Engineers at Northrop designed the 17 into an all-weather fighter. Every advanced avionic package, electronic system, and aerodynamic characteristic were implemented into the new 17 fighter. What emerged was a truly remarkable flying machine. The first test production FY-17, tail number 72-01569 was fitted with two General Electric YJ101-GE-100 Turbojet engines with afterburning capable of generating 14,415lb of thrust. The engines were mounted close together in order to reduce the asymmetric effects on handling in the event of an engine malfunction. The 17 fuselage was made primarily of graphite composite alloys. The FY-17 was the first aircraft design to incorporate leading edge root extensions. These extensions gave the FY-17 excellent stability at a high angle of attack.

The wing structure implemented a system of full span leading edges and half span trailing edges flaps to provide the aircraft with good low speed performance. A set of conventional ailerons and differential tailerons provided the 17 with its roll control system. The wingtips were fitted with launch rails for mounting air-to-air missiles. A twin tailfin configuration, canted outwards in order to keep them out of the wake from the wing, was incorporated. The aircraft’s rudders were relative small, reaching only to halfway up the fins. A conventional cockpit was incorporated with the purpose of providing the pilot with an excellent viewing area. The three wheel landing mechanism was simple. It was composed of single-shock struts and high pressure tires placed on each of the landing wheels.

Platform Specifications

Length 55’-0”
Height 14’-6”
Wing Area 350sq ft
Span 35’-0”
Maximum Weight Capacity 30,567lb

Operational Range 2,790 miles
Service Ceiling 59,800’

Maximum Speed 1,316mph at 40,000’

Weapon System Capability

One General Electric 20mm M61a1 Vulcan Cannon
Two AIM9 Sidewinder Missiles
Pylons for Two Mk 84 bombs

On the morning of June 9th, 1974; the FY-17 took to the air for its maiden fly. A second prototype was built, tail number 72-01570 for testing purposes only. Between the two units, they logged over 600 flights. The aircraft was highly regarded by the sixty test pilots who flew it. There were rumours that the 17 flew mock combat missions against capture Mig 17s and 21s over the Nevada desert and that the aircraft performed beyond expectations, but ultimately, the FY-17 lost the “Deal” competition and the FY-16 went on to become NATO’s mainstay, front-line fighter. Although stunned by the decision made by the Air Force, Northrop still planned to produce the aircraft. But export orders for the FY-17 were slow to come and the program was terminated soon after its showdown with the FY-16. But the demise of 17 design concept was short-lived. In September 1974, the McDonnell Douglas Corporation agreed to develop a naval version of the 17, which was called the Hornet. The Hornet and its successor, the Super Hornet have become the United States Navy’s main fleet defence fighter as well as attack and reconnaissance aircraft.