The IHI XF9 is a low-bypass

afterburning turbofan An afterburner (or reheat in British English) is an additional combustion component used on some jet engines, mostly those on military supersonic aircraft. Its purpose is to increase thrust, usually for supersonic flight, takeoff, and co ...

engine developed by the Acquisition, Technology & Logistics Agency (ATLA) of

Ministry of Defense {{unsourced, date=February 2021 A ministry of defence or defense (see spelling differences), also known as a department of defence or defense, is an often-used name for the part of a government responsible for matters of defence, found in state ...

of Japan (MoD) and

IHI Corporation , formerly known as , is a Japanese engineering corporation headquartered in Tokyo, Japan that produces and offers ships, space launch vehicles, aircraft engines, marine diesel engines, gas turbines, gas engines, railway systems, turbochargers f ...

Overview

The XF9 is a product of an ATLA project ''Research on fighter engine system'' (2015–2019) which followed two preliminary projects, ''Research on main components of next generation engines'' (2010–2015) and ''Research on fighter engine elements'' (2013–2017). Started after development of the XF5 turbofan engine (1995–2008), these research projects are preliminary works for Japan's future fighter program or the successor to the Mitsubishi F-2 fighter. The basic concept is to produce a "slim and high-power" engine, thereby creating more capacity for accommodating fuel and weaponry inside the fuselage of stealth fighter to reduce radar cross section. The concept, dubbed High-power Slim Engine, also appears in an MoD report titled ''A vision for research and development of future fighter aircraft'' (2010) as the powerplant for a conceptual Japanese future fighter, the i³ FIGHTER. While its predecessor, the XF5, was a small engine, the XF9-1 prototype is close to the

General Electric F110 The General Electric F110 is an afterburning turbofan jet engine produced by GE Aviation. The engine is derived from the General Electric F101 and shares its core design, and primarily powers tactical fighter aircraft. The F118 is a non-afterb ...

in size, and is comparable to the

Pratt & Whitney F119 The Pratt & Whitney F119, company designation PW5000, is an afterburning turbofan engine developed by Pratt & Whitney for the Advanced Tactical Fighter (ATF) program, which resulted in the Lockheed Martin F-22 Raptor. The engine delivers thrust ...

in terms of thrust class. With the core that withstands 2,073 K (1,800℃) class Turbine Inlet Temperature, the XF9-1 produces a high thrust, improving fuel economy at the same time. As of 2018, the officially publicized thrust level of the prototype is "11 tons (107 kN / 24,000 lbf) or more" in military thrust and "15 tons (147 kN / 33,000 lbf) or more" with afterburner. The XF9 is designed to be adaptable to a wide range of thrust level, higher or lower, depending on requirement; and the future fighter engine program is conducted with a target maximum thrust of 20 tons (196 kN / 44,000 lbf) in mind, which was unveiled at the ATLA Technology Symposium 2018.

Technical features

The XF9-1 is a twin-spool axial-flow afterburning turbofan with a dual redundant FADEC, consisting of a 3-stage fan, a 6-stage high-pressure compressor, an annular type combustor, a single-stage high-pressure turbine, a single-stage low-pressure turbine, an afterburner, and a convergent-divergent nozzle. The concept, slim and high-power, resulted in an approximately 30% higher thrust per unit cross-sectional area compared to the GE F110 the Mitsubishi F-2 is equipped with. To achieve this thrust level, a higher combustion temperature (1,800℃ class) and an optimized aerodynamic design were needed, which in turn required advanced material, manufacturing, cooling and fluid analysis technologies. Each of the rotors is a

blisk A blisk (portmanteau of bladed disk) is a turbomachine component comprising both rotor disk and blades. It serves as a critical component of the engine compressor to allow a sufficient quantity of compressed air to enter the engine for combustion ...

to contribute to weight reduction and downsizing. The combustor is equipped with patented new-type burners, Wide-angle Swirler, to facilitate stable combustion and more uniform heat distribution at the outlet. To reduce cost, the high-pressure turbine disk is manufactured by forging technique instead of

powder metallurgy Powder metallurgy (PM) is a term covering a wide range of ways in which materials or components are made from metal powders. PM processes can reduce or eliminate the need for subtractive processes in manufacturing, lowering material losses and ...

(PM) employed in the XF5; the material is a nickel-cobalt base superalloy, TMW-24, developed by NIMS, of which heat resistance is comparable to that of PM superalloys. Turbine blades made of a Japanese fifth generation nickel base single-crystal superalloy are friction welded to the disk to form the blisk, which is enclosed in the shroud made of

ceramic matrix composites In materials science, ceramic matrix composites (CMCs) are a subgroup of composite materials and a subgroup of ceramics. They consist of ceramic fibers embedded in a ceramic matrix. The fibers and the matrix both can consist of any ceramic mat ...

. The afterburner is a new type to eliminate the conventional annular flame holders to improve efficiency. As another characteristic, the XF9-1 incorporates a starter generator that outputs 180 kW, meaning that a twin-engine fighter with this engine can be supplied with as much as 360 kW of electricity by engines alone. The capacity is quite large compared to that of conventional fourth or fifth generation fighters such as the Boeing F-15E (76 kW), the

Lockheed Martin F-22 The Lockheed Martin F-22 Raptor is an American single-seat, twin-engine, all-weather stealth tactical fighter aircraft developed for the United States Air Force (USAF). As the result of the USAF's Advanced Tactical Fighter (ATF) program, ...

(130 kW), and the

Lockheed Martin F-35 The Lockheed Martin F-35 Lightning II is an American family of single-seat, single-engine, all-weather stealth multirole combat aircraft that is intended to perform both air superiority and strike missions. It is also able to provide ele ...

(160 kW), allowing for next generation avionics and other high power consuming onboard devices and equipment. XVN3-1 EN

In addition, a research to demonstrate thrust vectoring control and its failure handling technology is conducted from 2016 to 2020 in parallel with development of the engine. This research is aimed at achieving higher maneuverability and smaller control surfaces favorable to stealth aircraft. For the XF9-1, the XVN3-1 three-dimensional thrust vectoring nozzle is available, which can deflect thrust up to 20 degrees in all circumference directions.

Timeline

* 1995-2008 ** Research and development of the XF5 engine * 2010 ** Research on main components of next-gen engines (–2015) * 2013 ** Research on fighter engine elements (–2017) * July 2017 ** Delivery of the core engine * June 2018 ** Delivery of the prototype engine (XF9-1)

Specifications

References

External links