In late January, Lockheed Martin will mark a major anniversary in the astonishing history of its F-16 programme: 50 years since the first flight of a prototype developed for the US Air Force (USAF).
It is no exaggeration to say that the YF-16’s debut outing from Edwards AFB in California on 20 January 1974 represented an unplanned and bumpy start for what was to become today’s most widely-flown fighter, as test pilot Phil Oestricher recalled during a 2012 interview.
“I had intended all the way along to put a little bit of daylight under the wheels, maybe a foot or two, fly it about 1,000 feet down the runway and land it, in the meantime checking out the lateral or roll response sensitivity,” he said of what had officially been planned as a first high-speed taxi test.
“I started the run – the airplane accelerated very smartly, of course – and pulled the power back… [but] we had a wiring problem in the airplane where the exhaust nozzle would not open up, thus killing thrust.
“The airplane was very sensitive in roll: it rolled violently left, I countered with an equally violent right command, then we were instantly in a pilot-induced oscillation, with the airplane rolling back and forth very quickly.”
With the fighter only feet off the ground and turning sharply left, Oestricher had to act instantly. “I could see it was going to go out into the dirt, so I just powered it up and let go of the controls and let it fly away. I made a rather extended turn to the downwind, came around and landed. Most of the flight was done with me barely touching the stick, if at all.”
The surprise debut resulted in light damage, with the aircraft’s starboard horizontal tailplane and port wingtip missile rail found to have struck the ground after it became airborne at about 135kt (250km/h).
Barely two weeks later, Oestricher put the same YF-16 through its first official outing, on 2 February completing a 90min sortie from Edwards. This included taking the fighter to 350kt (647km/h), 30,000ft and manoeuvring at a maximum of 3g.
“The F-16’s maiden flight in 1974 marked a watershed moment. It introduced a highly agile and cost-effective fighter concept that revolutionised modern air warfare,” says Lockheed.
SERVICE REQUIREMENT
Developed by General Dynamics, the single-engined jet was intended to meet the USAF’s broad need for a lightweight fighter (LWF). This drew on lessons learned from the Vietnam War, where its aircraft had fared poorly in close combat against Mikoyan-Gurevich’s more agile MiG-15.
General Dynamics chose the Pratt & Whitney F100 engine – a powerplant already employed with the USAF’s McDonnell Douglas F-15 – for its candidate.
Also pursuing the LWF requirement was Northrop, with the twin-engined and twin-tailed YF-17. Both companies produced a pair of prototypes, under USAF contracts worth approaching $40 million each.
Reviewing General Dynamics’ design in our 7 February 1974 issue – when we also published our first cutaway drawing of the type – Flight wrote of the LWF process: “complete responsibility resides with the [bidding] company and no detailed military specifications have had to be met”.
With this free rein, the YF-16’s designers “combined a host of advanced technologies that had never been used in operational fighters”, Lockheed says. “A blended wing-body, variable camber wings, and forebody strakes provided extra lift and control. Fly-by-wire flight controls improved response time and replaced heavy hydro-mechanical systems with lighter and smaller electronic systems.
“A side-mounted throttle and stick, head-up display, 30° seat back angle, hands-on controls, and bubble canopy improved the pilot’s g-tolerance and situational awareness. The YF-16 was the first to incorporate all of them into a producible design.”
BUBBLE VISION
Referring to the use of a bubble canopy, which gives the pilot 360° vision in the upper hemisphere, Flight’s report noted: “There is a substantial supersonic drag penalty associated with this type of canopy, but General Dynamics points out that visibility in combat was the requirement, and by far the greater part of dogfighting takes place at speeds below Mach 1.”
Following a short flight-test campaign, the USAF selected the F-16 as the winner of its formal Air Combat Fighter requirement in January 1975. Its decision was driven by a “Hi-Lo” operating concept, which would employ the type in partnership with the larger and more expensive F-15.
Lockheed hails the vision of a so-called ‘Lightweight Fighter Mafia’ group in the USAF and US Department of Defense, which “favoured simple and small fighter designs that could change direction and speed faster than their potential adversaries – designs that were harder to detect, and inexpensive to produce, operate and maintain”.
Flight’s coverage after the selection’s confirmation noted strong opposition from some parties who had favoured a twin-engined solution – including the US Navy (USN) – stating: “The decision ignores the strenuous efforts made in recent months to ensure that the selected aircraft would be as attractive as possible to known and expected overseas customers.”
Such concerns were to prove ill-founded, even though the defeated YF-17 would evolve into the also highly successful F-18, first flown in November 1978. Produced by McDonnell Douglas and later Boeing, the type was sold to the USN and US Marine Corps, plus export customers Australia, Canada, Finland, Kuwait, Malaysia, Spain and Switzerland. Production of the current F/A-18E/F Super Hornet will end in 2025.
With its selection made, the USAF funded General Dynamics to start work on eight full-scale development (FSD) aircraft, which featured major, but mostly internal design changes.
“The YF-16 validated the aerodynamics, propulsion, and handling qualities of the aircraft’s basic design. With the major design issues out of the way, engineers concentrated on internal details, such as the electrical system, hydraulics, and avionics, with the FSD aircraft,” Lockheed says.
“The evolution of the production F-16 became a balancing act between adding and improving capabilities and maintaining the original design’s optimised performance.”
Changes meant the fighter gained an extra 13in in length, and its nose “acquired a slight droop to accommodate the Westinghouse APG-66 multimode radar”.
“To respond to the need for larger air-to-ground [weapon] payloads, the wing and tail surfaces were enlarged to carry the extra weight,” Lockheed says. Wing area was increased to 27.8sq m (300sq ft), from 26sq m, the horizontal tail and ventral fins by about 15%, and flaperons and speed brakes by roughly 10%.
The airframe was also strengthened, enabling an additional two hardpoints to be added under its wing, boosting its total count to nine. Its canopy was improved, to withstand impact by a 1.8kg (3.9lb) bird at 350kt.
Combined, the enhancements meant that the fighter would be capable of an unrivalled 9g performance with a full internal fuel load.
A first production F-16A built for the USAF made its debut flight in December 1976, and its first operational examples arrived at Hill AFB in Utah in January 1979. The service officially named the model the Fighting Falcon, although it is widely also nicknamed the Viper.
European Partner Air Forces Belgium, Denmark, the Netherlands and Norway had also ordered a combined 348 of the type, with their aircraft to be assembled in Belgium and the Netherlands.
CAPABILITY UPDATES
Multi-role capability followed from 1981, when the enhanced C/D model – with a maximum take-off weight (MTOW) of 17,000kg – achieved initial operational capability. Further updates to the type, which is powered by either an F100 or GE Aerospace F110, were declared in service by the USAF in 1989 as the Block 40/42 version and 1994 for the Block 50/52.
The USAF notes that during Operation Desert Storm in 1991, its F-16s flew “more sorties than any other aircraft” and struck “airfields, military production facilities, Scud missile sites and a variety of other targets”. The region also provided the first air-to-air kill for an F-16 in its service: a successful ‘no-fly’ zone engagement of an Iraqi air force MiG-25 using a Raytheon AIM-120 AMRAAM, during the subsequent Operation Southern Watch.
Shortly afterwards, Lockheed in 1993 acquired General Dynamics’ tactical military aircraft business, including the F-16’s Fort Worth final assembly line in Texas. This grew to be a mile long, and now hosts completion of Lockheed’s F-35 stealth fighter. The last F-16 delivery from the site was made in 2017, with the aircraft bound for service with the Iraqi air force.
In 2023, first shipments were completed from a new production facility in Greenville, South Carolina.
Some 4,591 F-16s had been built as of mid-December, with the global fleet having recorded over 13 million sorties and 19.5 million flight hours. Lockheed notes that over the life of the programme, around 140 versions have been produced, through various blocks, models and national-specific adaptations.
Today, F-16s are in frontline use in 25 nations, with Slovakia and Bulgaria to follow and Ukraine in 2024 to begin fielding at least 61 examples which F-35 buyers Belgium, Denmark, the Netherlands and Norway will transfer from surplus stocks. Partially in support of the pending equipment transfer to Kyiv, Lockheed in late 2023 established a new European F-16 training centre at Fetesti air base in Romania.
Cirium fleets data indicates that the current active F-16 inventory totals 2,852 military aircraft (see table, below), with another 327 recorded as currently in storage.
Lead operator the USAF has progressively reduced its active F-16 fleet to slightly below the four-figure mark: some 948 were in use as of mid-December. The service’s frontline C/Ds are aged between 18 and 41 years, while its fleet total also includes 62 A/C-model examples modified by Boeing into QF-16 target drones, and examples used by the Thunderbirds aerobatic display team.
Lockheed Martin F-16 global fleet | |||
---|---|---|---|
Country | Active | Ordered | On option |
Bahrain | 24 | 14 | |
Belgium | 52 | ||
Bulgaria | 8 | 8 | |
Chile | 46 | ||
Denmark | 43 | ||
Egypt | 218 | ||
Greece | 154 | ||
Indonesia | 32 | ||
Iraq | 34 | ||
Israel | 224 | ||
Jordan | 59 | 12 | |
Morocco | 23 | 24 | |
The Netherlands | 31 | ||
Oman | 23 | ||
Pakistan | 75 | ||
The Philippines | 12 | ||
Poland | 48 | ||
Portugal | 25 | ||
Romania | 20 | 32* | |
Singapore | 60 | ||
Slovakia | 1 | 13 | |
South Korea | 167 | ||
Taiwan | 139 | 66 | |
Thailand | 49 | ||
Turkey | 243 | ||
Ukraine | 61* | ||
United Arab Emirates | 78 | ||
USA (Air Force) | 948** | ||
USA (Navy) | 21 | ||
Venezuela | 15 | ||
Total | 2,852 | 125 | 32 |
Source: Cirium fleets data/Lockheed Martin | |||
Notes: *Secondhand **Includes 62 QF-16 target drones |
The three leading users behind the USAF are the air forces of Turkey (243), Israel (224) and Egypt (218). Other notable users include the United Arab Emirates, which flies 78 E/F-model examples in the advanced Block 60 standard, which introduced an active electronically scanned array (AESA) radar with the type.
NON-MILITARY USERS
US adversary training provider Top Aces, meanwhile, has become the first such operator to field F-16s, with 10 N-registered examples – nine As and one B – in use, aged up to 43 years.
Other non-military users are listed as Lockheed, with two, and single examples are with Calspan, Israel Aerospace Industries and NASA.
In terms of engine choice, Cirium records a fairly even split: of all F-16s currently flying, 53% are F100-powered, while the remainder use the F110.
By December 2023, Lockheed had handed over three Greenville-built aircraft in the F-16’s latest Block 70 standard. Initially to be employed in support of pilot training in the USA, these include the first two of 16 examples for Bahrain and one of 14 ordered by Slovakia.
New capabilities embedded with the Block 70/72 standard include Northrop Grumman’s APG-83 AESA radar, plus “advanced avionics, a modernised cockpit with new safety features, advanced weapons, conformal fuel tanks [CFTs], an improved-performance engine, and an extended structural service life of 12,000h” – equivalent to at least 40 years of operational use.
MTOW also climbs to almost 21,800kg, with engine thrust in the 29,000lb (129kN) class.
Lockheed notes that the CFTs – which increase internal fuel capacity by almost 1,360kg – provide extended range “without sacrificing the aerodynamic performance of the jet”.
The company also notes that its automatic ground collision avoidance system has saved the lives of 13 USAF personnel since its introduction in late 2014.
“There are currently 125 F-16s for five countries in the production backlog,” Lockheed says: its other customers are Bulgaria (8), Morocco (24) and Taiwan (66). To date, the majority of buyers for the enhanced version have selected GE’s F110 engine: only Morocco’s examples will have the F100.
Bulgaria plans to boost its acquisition by another eight jets, and Jordan intends to buy 12. And in 2023, the Philippines emerged as another potential future customer, with a need for a dozen advanced fighters.
Lockheed notes that its current production activity is supported by roughly 470 suppliers globally, with “major components produced in eight countries”.
Deliveries will run through at least late this decade, but the company has previously said that it expects to secure additional orders in “Europe, Asia and Africa”. Opportunities include an Indian air force requirement for which Lockheed is offering a rebadged F-21, to be produced in the country if selected.
“We leverage emerging technologies to advance F-16 performance for future production as well as upgrades and modernisation activities,” the airframer says. Greece, South Korea and Taiwan – which fly a combined 460 examples – plus another undisclosed operator are in the process of updating their fleets with the APG-83 radar, a high-resolution centre pedestal display and replacement modular mission computer, it notes.
DEFENDING UKRAINE
2024 will again see much focus placed on the F-16, as the type bolsters the capabilities of the war-depleted Ukrainian air force. Its 50th anniversary will also be one of the show themes for the 19-21 July Royal International Air Tattoo in the UK, with multiple nations due to proudly exhibit their aircraft.
Describing the jet as “the most dominant and capable fourth-generation fighter ever produced”, Lockheed says: “This foundation of innovation, versatility and affordability has been integral to the F-16’s enduring global success over the past five decades. The jet stands as one of the most iconic fighters in history. It is a symbol of enduring partnerships, industrial collaboration and security.
“The fundamental strengths of the original design remain,” it adds. “At the heart of every Fighting Falcon is the lightweight fighter concept championed by Colonel John Boyd and the other members of the Lightweight Fighter Mafia.”