Upgrading a US Air Force classic Flying F-16s to 2048


David C Isby reviews the disposition of the US Air Force F-16 Fighting Falcon fleet, still the backbone of its combat aircraft fleet

Seen at low-level in California, Block 30 F-16C 86-0304/AK is assigned to the 18th Aggressor Squadron home-based at Eielson Air Force Base, Alaska. The unit deployed to Nellis Air Force Base, Nevada during October to support the US Air Force Weapons School.
Dan Stijovich

The Lockheed Martin F-16 Fighting Falcon ighter is the most numerous ighter in the US Air Force inventory, with 768 single-seat F-16Cs and 155 two-seat F-16Ds as of the start of FY2018.

Since 2001, US Air Force F-16s have been extensively used in combat operations in Afghanistan, Iraq and Syria. US Air Force F-16 units specialise in diferent primary missions. The 35th Fighter Wing based at Misawa Air Base, Japan, and the 20th Fighter Wing based at Shaw Air Force Base, South Carolina, specialise in the suppression of enemy air defences, once again considered a vital mission area. The US National Defense Strategy emphasises readiness against great powers that have sophisticated integrated air defence systems. Some Air National Guard (ANG) and Air Force Reserve (AFR) units hold homeland air defence as their primary mission, but even these units deploy and their interception skills have proven valuable in NATO’s eastern frontiers. While the ANG and AFR are today lying some of the oldest Block 30 F-16 aircraft, Congress has ensured they have access to dedicated funding lines to help keep these aircraft capable.

F-16s have always had a strong air-toair capability, made more lethal by their current missile armament options. An F-16C scored the US Air Force’s most recent airto- air victory, over Kosovo in 1999. Today, however, it is primarily used for air-toground missions, using weapons ranging from its internal 20mm M61A1 cannon – especially in situations when there is a risk of collateral damage – to the Lockheed Martin AGM-158B Joint Air-Surface Standof Missile – Extended Range.

Within the US Air Force, the F-16 receives much less attention than the type that is planned to replace it by 2048, the Lockheed Martin F-35A Lightning II. The latest international versions of the F-16, brand-new of the inal assembly line in Greenville, South Carolina (where it moved from Fort Worth Texas in November 2017), have capabilities far beyond anything in the US Air Force.

The last F-16 was delivered to the US Air Force in 2005, the average age of the fleet is 25 years, and none of them can match the high technology systems incorporated in the latest Block 70G F-16V under development for Bahrain; the Gulf nation is beneiting from a decade of Lockheed Martin-developed upgrades and technology spin-ofs from the F-35 programme. Nor are international F-16Vs the end of the story. There are many friendly countries operating F-16s today that are unlikely to be approved as export customers for the F-35. As such, these nations may buy advanced F-16s and keep production going into the 2020s, creating more upgrades that could be incorporated into ageing F-16s.

While those new F-16s being developed for foreign nations today overshadow the ageing US versions, the US Air Force beneits from the live production line by way of reduced costs of both replacement parts and upgrades, even though the Air Force is no longer buying F-16s.

Operationally, widespread use of F-16s by coalition air arms in the skies of Afghanistan, Iraq, Libya and Syria has made their incorporation into combined air operation, as well as their sustainment, more efective. Even though the F-16s involved varied widely in configuration and capabilities as well as their pilots’ readiness to take part in multinational operations, sharing the same type of aircraft makes sharing everything else easier.

Radar upgrades

The US Air Force is reluctant to invest in upgrading combat aircraft, preferring instead to buy new aircraft. Cancellation, in 2014, of the Combat Avionics Programmed Extension Suite (CAPES) relected the rising cost of introducing the F-35A into service, at the same time as having to deal with the efects of budget sequestration and spending caps.

CAPES was an upgrade destined for 300 F-16C and F-16Ds, involving the Northrop Grumman APG-83 Scalable Agile Beam Radar (SABR) and Lockheed Martin as prime contractor. The APG-83 SABR is an active electronically scanned array (AESA) radar capable of detecting small targets amidst surface clutter for anti-UAV missions and cruise missile defence.

The CAPES upgrade was also to have included a new central display unit and cockpit display, the Terma North America ALQ-213 Electronic Warfare Management System, the integrated broadcast system, datalink enhancements and integration of new cockpit avionics.

In the years since the cancellation of CAPES, the Air Force has looked at less expensive upgrade options. In 2015 and 2016, the F-16 Radar Modernization Program carried out developmental testing of both the SABR and its competitor, the APG-79- derived Raytheon Advanced Combat Radar at Edwards Air Force Base, California. Test results were used to help meet a 2015 urgent operational need (UON) for ANG units assigned to the North American Air Defense Command for acquisition of a limited number of AESA radars to upgrade some F-16C and F-16Ds in the homeland air defence mission. A response to the UON was delayed as the Air Force studied whether to upgrade ANG Block 30 F-16s or, instead, other later Block F-16s, and whether the radar should be integrated with other Air Force systems (with air-toground capabilities included in the radar) or procured on a standalone basis.

A recent colour scheme to appear with the Eielson-based 18th Aggressor Squadron features a three-colour splinter pattern as seen on Block 30 F-16C 86-0310/AK.
Dan Stijovich
A Block 52 F-16C assigned to the 157th Expeditionary Fighter Squadron on the boom during a close air support mission over Iraq in support of Operation Inherent Resolve. The aircraft is armed with two 500lb GBU-54 Laser JDAMs (left pylon) and at least two 250lb GBU-39/B Small Diameter Bombs (right pylon).
SSgt Keith James/US Air Force

Given that Raytheon did not submit a bid, on May 31, 2017, the Air Force awarded Northrop Grumman a contract for 72 APG-83 SABR radars. The first deliveries of operational F-16s retrofitted with the APG-83 radar are scheduled to take place by January 2019. Previous unconfirmed reports have said that the District of Columbia ANG’s 121st Fighter Squadron will be the first unit to receive AESAA recent colour scheme to appear with the Eielson-based 18th Aggressor Squadron features a three-colour splinter pattern as seen on Block 30 F-16C 86-0310/AK. Dan Stijovich equipped F-16s, because of its role in the air defence of the national capital area, as well as having a deployment capability. The 121st Fighter Squadron is based at Andrews Air Force Base, Maryland, which is located approximately 15 miles (24km) from Washington DC.

The Air Force is still looking at providing AESA radars and a range of other upgrades (including avionics and electronic warfare capabilities) for an undetermined number of F-16s under its Long-Term Viper Program. The future of F-16 upgrades may depend on what the Air Force decides to do about its F-15C and F-15D Eagle force. Retiring the F-15C in the near-term future and without accelerating F-35A procurement, which appears to be the most likely option, means additional AESA-equipped F-16s will be needed to take over air defence missions currently flown by F-15Cs.

SLEP and structure

Years of deployments to conflicts worldwide since 2001 required many flight hours by US Air Force F-16s. The F-16 Service Life Extension Program (SLEP) – which strengthens the structure rather than providing new capabilities – followed static testing conducted under the Full Scale Durability Test (FSDT) program undertaken between 2012 and 2017. The SLEP will extend the fatigue life of Block 40, Block 42, Block 50 and Block 52 F-16Cs and F-16Ds to 13,856 equivalent flight hours – the figure demonstrated as achievable through the FSDT – from their original 8,000-hour service life. The SLEP will replace structural bulkheads and longerons, modify wing and wing-box assemblies, install new structural brackets and beam supports and reskin the upper fuselage.

Block 40 F-16C 88-0454/HO is the current mount of the 8th Fighter Squadron commander, seen on take-off from March Air Reserve Base, California during a cross country flight from its home base, Holloman Air Force Base, New Mexico.
Dan Stijovich

A request for proposal (RFP) for the SLEP was issued by the Air Force in November 2017. The scope of the RFP was for some 841 aircraft, an increase from the 300 that had previously been considered (although the number that will actually go through the process remains unknown).

The work, carried out at Ogden Air Logistics Complex at Hill Air Force Base, Utah, involves installation of SLEP kits comprising parts provided by small suppliers with support from Lockheed Martin. Each F-16 going through the nine-month SLEP process at Hill will cost some $2.4 million. The first of four SLEP validation and verification aircraft, an F-16C once flown by the Thunderbirds display team, went through the upgrade in April 2018. Production is to run to FY2023 with an option to extend to FY2025.

Software and systems

Reportedly, a quarter of F-16 losses have been caused by controlled flight into terrain. This risk, especially of crashes caused by a pilot’s loss of consciousness, has been reduced by installation of the Lockheed Martin F-16 Automatic Ground Collision Avoidance System (Auto GCAS).

Auto GCAS, which has been installed on most of the US Air Force’s F-16s through an upgrade that started in 2014 after a prolonged development programme at the Air Force Research Laboratory at Wright Patterson Air Force Base, Ohio, and flight testing at Edwards Air Force Base, California. Auto GCAS automatically overrides flight controls and initiates a pull-up manoeuvre and has already saved unconscious F-16 pilots from crashing. Four saves of US and international pilots were recorded between 2014 and 2016 alone; the number increased to seven by 2018. In December 2016, Raytheon was selected to provide a new Modular Mission Computer Upgrade (MMCU) for US Air Force F-16s.

The MMCU, using commercial off -the-shelf technology, reportedly provides double the processing power of current computers and performance comparable to the mission computer in the F-16V. The first MMCU systems are scheduled to be delivered in 2020. In November 2018, the Air Force selected the Avalex Cockpit Management Unit for a fleet-wide F-16 upgrade as part of the Mobile User Objective System. This will provide F-16s with a new cockpit control panel for networked communications and electronics, replacing current analogue and appliqué controls, as well as controlling the upgraded Rockwell Collins ARC-210 radio.

The longest-running F-16 upgrade, the Common Configuration Implementation Program, started in 2000. It provides common hardware and software capability for US and international Block 40, Block 42, Block 50 and Block 52 F-16Cs and F-16Ds. Installation of the current M7+ Operational Flight Program (OFP) started in 2016, providing software for the Raytheon AIM-9X Block II air-to-air missile, the ALQ-213, GPS/INS navigation systems and radar upgrades; the follow-on M8 OFP is currently under development. Upgrading the software of some 319 Block 30 and Block 32 F-16Cs and F-16Ds operated by the ANG and AFR under the Software Capability Upgrade (SCU) programme, the current version of which is dubbed SCU-9, will provide them with weapon engagement zone capabilities by March 2023.

Integrating the F-16 into networked air operations has been a major objective of network connectivity systems developed in recent years; these systems safely link legacy fighters with the new-generation F-22 Raptors and F-35A Lightning IIs. While the Talon HATE system, housed in a pod, has been used primarily on F-15s, other systems have been flown on F-16s.

Under a contract with Rockwell Collins announced in November 2018, anti-jam GPS receivers will be fitted to F-16s operated by the ANG and AFR, allowing reliable navigation in the face of hostile jamming and meaconing efforts.

Evolution of the basic F-16 design to today’s multi-role network-capable aircraft has been made possible, in large part, by the introduction of pod-mounted systems. One of many examples is the Northrop Grumman ASQ-236 AESA radar pod, a tactical Ku-band system that according to the manufacturer provides all-weather target detection, track and engagement capability with a synthetic aperture radar mode.

Currently operational on F-15E Strike Eagles, the Tucson-based Air National Guard- Air Force Reserve Test Center evaluated the ASQ-236 on F-16s in 2017. A new electronic warfare capability for the F-16 housed in a pod – to be procured under Section 804 rapid prototyping authority – is currently being considered.

The Northrop Grumman ALQ-131 electronic countermeasures pod, used by US and international F-16s, is being upgraded, including a new digital exciter receiver. F-16s use pylons fitted with Pylon Integrated Dispenser System, Universal (PIDSU), a chaff and flare dispensation system. Under a programme started in 2014, Terma North American is upgrading port and starboard pylons carried by 215 ANG F-16s with its improved chaff and flare countermeasures dispenser dubbed Flare-Up. Previously configured as PIDSU, each upgraded pylon is configured as PIDS+ with Flare-Up dispensers positioned such that decoys are dispensed diagonally downward. Flare-up dispensers are managed by the Terma ALQ-213 Electronic Warfare Management System, which is presented with threat information by the missile warning system. Upgrade of all 215 sets of pylons will be completed in 2019.

US Air Force F-16s have also had new weapons added to their arsenal. The BAE Systems Advanced Precision Kill Weapons System, a 2.75in laser-guided rocket system, is now operational. Raytheon’s GBU-53 StormBreaker Small Diameter Bomb II will soon be carried by the F-16 after it enters US Air Force service. While US Air Force F-16s do not currently have the nuclear delivery mission of some NATO aircraft, the new B61- 12 gravity bomb was tested for integration with the F-16 in 2017.

All tooled-up. Block 52 F-16C 93-0533 assigned to the 157th Expeditionary Fighter Squadron configured with a weapon payload comprising two AIM-120 AMRAAM and two AIM-9 Sidewinder missiles, two 300-gallon drop tanks, two 500lb GBU-54 Laser JDAMs, four 250lb GBU-39/B Small Diameter Bombs, and an AAQ-33 Sniper pod.
SSgt Keith James/US Air Force
Spangdahlem-based Block 50 F-16C 96-0080/SP is the current mount of the 480th Fighter Squadron commander. The jet is seen on take-of from Kallax Air Base, Sweden during the recent NATO exercise, Trident Juncture 2018.
Christian Timmig/Svenska Flygvapnet

Unmanned and unafraid

Boeing is the prime contractor for converting early-production F-16s into QF-16 Full-Scale Aerial Targets (FSATs). The first of the 126 QF-16s ordered by the Air Force was delivered in March 2015, and the type achieved initial operational capability in 2016. Removed from storage at Davis-Monthan Air Force Base, Arizona, the QF-16s were put into service as FSATs for a unit cost of $1.3 million. Since then, the QF-16 has replaced the McDonnell Douglas QF-4 Phantoms previously used at Tyndall Air Force Base, Florida (where a number of QF-16s were destroyed by a hurricane in October 2018) and, in 2017, at Holloman Air Force Base New Mexico.

At Edwards Air Force Base, California, in March 2017, the two-week Have Raider II demonstration examined the operational capability of an unmanned version of the F-16 with a manned ground control system, and the capability for autonomous light.

The Air Force also demonstrated in-light teaming between manned and unmanned F-16s, as part of its work on a concept known as Loyal Wingman, which would use manned and unmanned aircraft with similar performance as part of a single light. The unmanned aircraft would be directed to carry out autonomous manoeuvres by the manned aircraft, rather than being lown remotely as with current UAVs.

Operations and availability

The US Air Force F-16 fleet has to deal with the requirement set out by Secretary of Defense James Mattis, in the autumn of 2018, that the mission availability rate for several ighter types, including F-16s, is to be raised to 80% from the current level of about 70% (the highest fleet wide baseline of any ighter afected) by the end of FY2019, while simultaneously reducing operations and maintenance costs.

Notable in this on-the-boom shot of a 157th Expeditionary Fighter Squadron Block 52 F-16C is a launcher pod on the right side pylon loaded with ten APKWS 2.75-inch rockets.
SSgt Keith James/US Air Force

This will require the Air Force to reprogramme funding and will likely lead to a number of F-16s – presumably older and less reliable aircraft – being cannibalised for spare parts and struck of charge, so they can no longer drag down the mission availability rate. The Air Force is also planning to make nearterm increases in its use of data collection and analysis to identify sustainability issues.

A Government Accountability Oice study, released on September 10, 2018, identiied the F-16 as one of the few types of aircraft with operating costs that had decreased over a ive-year period, largely due to savings in depot-level maintenance, despite the continuous ageing of aircraft. Diminishing manufacturing sources and delays in maintenance were identiied as reducing F-16 mission availability rates.

Under current planning, the US Air Force F-16 force structure will gradually reduce as the aircraft are replaced by F-35A Lightning IIs. The first operational F-35 wing, the 388th Fighter Wing based at Hill Air Force Base, Utah, had previously operated F-16s.

Vermont ANG’s 134th Fighter Squadron based at Burlington International Airport has passed its inal qualifications on its Block 30 F-16Cs and F-16Ds before it transitions to the F-35A as the first ANG F-16 unit to convert to the F-35A.

Luke Air Force Base in Arizona has for decades been the main Air Force F-16 training base, but the monumental facility near Goodyear is also starting to change. Most US Air Force F-16 pilot and technician training has moved to Holloman Air Force Base, New Mexico, Kelly Field, Texas, and Tucson Air National Guard Base, Arizona.

Despite assuming more of the US Air Force’s F-16 training mission, Arizona ANG’s 162nd Wing still made time to carry out its first overseas deployment in 31 years in September 2018, participating in Ample Strike 2018, a NATO exercise in the Czech Republic.

The next 30 years

As of today, the Air Force is looking ahead to another 30 years of service from its F-16s. Since it entered US Air Force service in 1978 with the then 388th Tactical Fighter Wing at Hill Air Force Base, Utah, the F-16 has made the efectiveness of US and coalition airpower possible by achieving and maintaining the ine balance between combat capability and afordability. Originally designed by General Dynamics, the F-16 will continue as a vital component of US Air Force airpower for decades to come. However, this will require investment now in upgrades that will allow the Fighting Falcon to remain viable in the face of emerging and more-lethal threats