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Boeing has marked the maiden flight of the first new F-15EX for the U.S. Air Force, paving the way for the first two examples to be delivered during the first quarter of this year. The first flight of F-15EX-1 took place on Feb. 2, 2021, from Boeing’s facility at Lambert International Airport in St. Louis. It marked an incredible milestone for the F-15 that came some 48 years after the maiden flight of the first McDonnell Douglas YF-15A in July 1972.
With Boeing F-15 chief test pilot Matt “Phat” Giese at the controls, the aircraft completed a 90-minute test flight before returning to the airport. Boeing said the flight was used to check out the avionics, advanced systems, and software. A test team monitoring the data collected during the flight in real time confirmed that the aircraft performed as planned.
“Today’s successful flight proves the jet’s safety and readiness to join our nation’s fighter fleet,” said Prat Kumar, Boeing vice president and F-15 program manager. “Our workforce is excited to build a modern fighter aircraft for the USAF. Our customer can feel confident in its decision to invest in this platform that is capable of incorporating the latest advanced battle management systems, sensors and weapons due to the jet’s digital airframe design and open mission systems architecture.”
“They go out and load the airplane up to 9G,” said Boeing test pilot Dan “Dragon” Draeger, as he commentated on the maiden flight. He added that the flight included general handling at 30,000 feet and then dropping down lower to 18,000 ft, including checking that the roll and G limiters were working throughout the flight envelope.
The F-15EX is the latest variant of Boeing’s so-called Advanced F-15, with the USAF having ordered an initial eight aircraft under a $1.2-billion deal that was announced in July 2020 as part of the U.S. Fiscal Year 2020 defense budget. The USAF is set to procure a minimum of 144 new F-15EX Eagles under an indefinite-delivery/indefinite-quantity (IDIQ) contract worth up to $22.89 billion, with the first 80 jets planned over the next five years.
The USAF has not purchased any new Eagles since the last F-15E Strike Eagle was built back in 2001. In recent years, fighter procurement has focused on Fifth-Generation stealthy platforms like the F-22A Raptor and F-35A Lightning from Lockheed Martin. While F-15EX procurement has drawn criticism from some former senior officers who say buying new Eagles is a retrograde step, the current USAF leadership says that it represents the most efficient and cost-effective means to replace its aging F-15C/D Eagles. Indeed, such is the pressure on Air Combat Command to recapitalize its fighter fleet, that it is also now evaluating a purchase of new F-16s from Lockheed Martin.
The decision to purchase the F-15EX as an off-the-shelf solution came following an extensive analysis of the USAF’s F-15C/D fleet and an upgrade proposal known as the 2040C. It was decided that procuring brand new aircraft from the “hot” F-15 production line represented far better value for money. In 2019, the then USAF Chief of Staff Gen David Goldfein said: “When we stopped [producing] the F-22, the plan was to put that money into an accelerated plan for the F-35. If that plan had been executed at the time we canceled the F-22, I should have 1,100 F-35s on the ramp today. I have less than 300. So I’ve got four fourth-generation [aircraft types] that are part of the inventory that I’ve got to maintain into the 2030s to keep the capacity I need to be able to meet combatant commander requirements. One’s not going to make it, and that’s the F-15C.”
“The only option that was available [and] was an affordable option was to leverage the hot line that currently exists — that has investment from both Saudi Arabia and Qatar — that allows me to put an F-15EX in the same hangar, use the same support equipment, have a local checkout for both maintainers and operators, and do it on a timeline that I can maintain the capacity I need,” said Goldfein. “So the F-15EX is to solve only one challenge I have and that is that the F-15Cs are not going to continue flying and I have to have that capacity. I’m not willing to put a nickel of F-35 money into the F-15EX — this is not a trade-off, this is capacity I need to fulfill a shortfall that’s staring me in the face.”
The F-15EX enables the USAF to leverage existing pilot training pipelines, infrastructure and experience to seamlessly replace the F-15C/Ds with the new two-seat F-15EX. The first two aircraft are being provided on a fast track to support ongoing USAF test work involving the new Eagle Passive Active Warning Survivability System (EPAWSS), which is centered at Eglin Air Force Base, Florida. The F-15EX is fitted EPAWSS, and it is also an upgrade for the existing fleet of F-15E Strike Eagles. Following aircraft are destined to join an operational evaluation program, the USAF Weapons School at Nellis AFB, Nevada, and the F-15 Formal Training Unit at Kingsley Field in Klamath Falls, Oregon, which should receive its first new jets in 2022. The first operational F-15EX unit is planned as the Air National Guard’s 142nd Fighter Wing, based in Portland, Oregon.
The first flight of the EX came less than a year after the maiden flight of the first F-15QA for Qatar, which took place on April 14, 2020. Boeing had been able to leverage long-lead items and add the F-15EX into the existing QA production line to help speed up the build process for the initial pair of jets. Qatar has 36 F-15QAs on order, and the F-15EX is broadly based on this variant, with a sprinkling of USAF-specific extras, such as EPAWSS. The F-15QA is in turn based on the F-15SA (Saudi Advanced), of which 84 planned examples have been delivered to the Royal Saudi Air Force (RSAF).
The F-15SA was the first of a new-generation of two-seat Eagles, known by Boeing as the Advanced F-15, which is the first Eagle to feature new flight control computers and a Digital Fly-By-Wire system, as well as digital avionics architecture. This has resulted in a far more robust flight control system, improved stability, and expanded weapons capability with the addition of two new wing hardpoints. It means the aircraft can act as a versatile “weapon truck,” and able to carry the kind of large hypersonic weapons that are in development.
The F-15QA builds on the SA through two key enhancements. Both the front and rear cockpits feature a new 11- by 19-inch Large Area Display, and the jets also incorporate structural enhancements that include the latest production techniques and give these Eagles a 20,000-flight-hour service life. Like other Advanced F-15s, the first F-15EXs will be powered by General Electric F110-GE-129 engines due to the urgency of the program. However, Pratt & Whitney will submit a proposal for its F100-PW-229 engines as an alternative powerplant for a planned competition for later examples.
Like the F-15QA, the F-15EX features the Raytheon AN/APG-82(v)1 Active Electronically Scanned Array (AESA) radar, which has also been retrofitted into USAF Strike Eagles. Unlike the Qatari aircraft, which feature a bespoke software suite, the F-15EX will field the Suite 9 Operational Flight Program, which aligns them with the latest F-15E Strike Eagle standard.
The Advanced F-15’s success has re-invigorated the sales market for the Eagle. In late January, Boeing was cleared to begin marketing activities with India for a derivative of the F-15EX. “Now that we have the marketing licence, it allows us to talk to the Indian Air Force directly about the capability of the fighter,” Ankur Kanaglekar, Boeing’s India Fighters Lead, told Reuters. Indeed, conversations were expected to continue this week during the Aero India tradeshow in Bengaluru.
The Indian Air Force has procured 36 Dassault Rafales, but still has a burgeoning requirement for another 114 fighters as part of its follow-on Multi-Role Fighter Aircraft (MRFA) requirement. Boeing is also expected to offer the Block III version of the F/A-18E/F Super Hornet to India, which recently demonstrated a ski-jump take-off capability. This is linked to an associated Indian Navy requirement for 57 new fighters to operate from its Short Take-Off But Arrested Recovery (STOBAR) aircraft carriers. Also in the running for the Air Force’s MRFA program are the Lockheed Martin F-16 Block 70/72 (known as the F-21, which is a specific Indian variant), the MiG-35, the Sukhoi Su-35, the Eurofighter Typhoon, the Saab Gripen E, and the Rafale. Israel, too, has expressed an interest in procuring up to 25 new Advanced F-15s, along with retrofit upgrades for 25 existing F-15Is.
The first flight of the F-15EX is the latest chapter in the remarkable 50-year story of the Eagle. A decade ago, with the final few F-15SGs for Singapore being completed, the St. Louis production line looked in danger of being closed for good. Today, with new production techniques, potential new customers, and a healthy order book, the Eagle’s talons look as sharp as they have ever been.