Boeing F-15SE Silent Eagle

The Boeing F-15SE Silent Eagle is a proposed upgrade of the F-15E strike fighter by Boeing using stealth features, such as internal weapons carriage and radar-absorbent material.^[3]

Design and development

A demonstration version of the F-15SE was first displayed by Boeing on 17 March 2009. The F-15SE will use fifth generation fighter technologies to reduce its radar cross-section (RCS). Distinguishing features of this version are the conformal weapons bays (CWB) that replace the conformal fuel tanks (CFT) to hold weapons internally and the twin vertical tails canted outward 15 degrees to reduce radar cross section. Weapons storage takes the place of most of each CWB fuel capacity. This variant will also have radar absorbing material where needed. The Silent Eagle was aimed at current F-15 users such as Israel, Saudi Arabia, Japan, and South Korea, among others.^[3][4][5]

The F-15SE is to have the level of stealth allowed for export by the U.S. government.^[6] Boeing has stated that this stealth will only be in the range of fifth generation aircraft such as the F-35 Lightning II from the frontal aspect.^[7] The F-15SE will have a Raytheon AESA radar, and a new electronic warfare system from BAE Systems. This stealth will be optimized for air-to-air missions (against X-band radars) and much less effective against ground based radars (which use other frequencies).^[8]

In March 2009, Boeing formally launched the F-15 Silent Eagle and began to offer it for international sales. The aircraft is capable of carrying both internal weapons and external weapons mounted on hardpoints under each wing. The F-15SE's lower cost compared to fifth generation fighters is intended to aid the aircraft's appeal to the export market. The aircraft would require export licenses similar to the F-35.^[8][9]

Unit cost has been estimated by Boeing at approximately US$100 million, including spares and support.^[9] The company has been seeking other companies to be risk sharing partners to reduce its development costs.^[10] Studies of different possible levels of reduction in radar cross-section (RCS) are underway.^[11] In June 2009, Boeing stated it planned for a demonstration flight of the Silent Eagle in the third quarter 2010.^[12]

During August and September 2009, Boeing performed radar cross section testing on an F-15E with different radar absorbent coatings to select a coating for the Silent Eagle.^[13]

Although Boeing had been in tentative talks with South Korea since 2009 regarding the purchase of the Silent Eagle, it was unable to market the aircraft to international customers before it received an export license from the United States government.^[14] The company filed for an export license in early 2010,^[15] and received it in July 2010.^[16] In August 2010, clearance was granted to export the radar cross-section treatments and electronic warfare suite of the Silent Eagle to ROK.^[17]

The first production F-15E (86-0183) was modified to the F-15E1 configuration to serve as a Silent Eagle demonstrator. It first flew on 8 July 2010 with a left-side conformal weapons bay^[1][16] and on 20 July 2010 launched an AMRAAM from the CWB.^[18]

New build Silent Eagles will be lighter and more fuel efficient than Strike Eagle conversions because of the canted tails, fly-by-wire controls, and digital EW equipment.^[19] This allows them to mount two additional weapons stations on the wings.^[20]

In November 2010, Boeing signed an agreement with Korea Aerospace Industries for KAI to design, develop, and manufacture the conformal weapons bay for the F-15SE.^[21] KAI had previously produced wings and forward fuselages for F-15K and F-15SG. A report in the Korea Times in January 2012 indicated that only 10% of the design work on the conformal weapons bays had been completed, the same report indicated that development of the canted vertical tails had been suspended in 2010.^[22] However, Boeing had stated that development continued with scale model wind tunnel tests scheduled for the spring of 2012.^[23]

Failed export bids

Diplomatic sources reported that on 6 July 2010, in a face to face meeting Israeli Prime Minister Benjamin Netanyahu asked U.S. President Obama to expedite the export of the "stealth F-15E" but received no reply.^[24] Israel had held a number of initial discussions regarding the fighter and its capabilities, considering it an alternative to the F-35 Lightning II.^[25] In August 2010, Israel chose to buy the F-35.^[26]

The Silent Eagle was bid for the Japanese F-X project. But Japan instead decided to purchase the F-35 in 2011.^[27][28]

In September 2009, Saudi Arabia was reported to be considering the purchase of up to 72 F-15 strike aircraft.^[29] Although they initially showed interest in the Silent Eagle,^[30] they ordered the less advanced F-15SA version in 2012.^[31][32]

For the South Korean F-X III fighter program, Boeing bid the Silent Eagle against the F-35 and Eurofighter Typhoon. Boeing would use existing F-15s for a flyoff against the Typhoon, and an F-35 flight simulator.^[33][34] On 18 August 2013, the South Korean Defense Acquisition Program Administration (DAPA) announced that the F-15SE was only remaining candidate. The F-35 had exceeded the budget and the Typhoon was disqualified for flaws in bidding documents. Ex-Air Force chiefs insisted that a stealth airplane should be chosen regardless of price and on 24 September 2013, the defense ministry rejected the award and said a new competition would be held.^[35] On 22 November 2013, it was reported that the ROK Air Force will purchase the F-35A. There is an opportunity for South Korea to buy other fighters, but Boeing has shifted from the F-15SE to the "Advanced F-15".^[36]

Specifications

Basic specifications listed are for the F-15E Strike Eagle, on which the F-15SE is based.

Data from USAF F-15E fact sheet,^[37] Davies,^[38] and Boeing Silent Eagle^[39]

General characteristics

• Crew: 2
• Length: 63.8 ft (19.43 m)
• Wingspan: 42.8 ft (13.05 m)
• Height: 18.5 ft (5.63 m)
• Wing area: 608 ft² (56.5 m²)
• Airfoil: NACA 64A006.6 root, NACA 64A203 tip
• Empty weight: 31,700 lb (14,300 kg)
• Max. takeoff weight: 81,000 lb (36,700 kg)
• Powerplant: 2 × Pratt & Whitney F100-229 afterburning turbofans, 29,000 lbf (129 kN) each

Performance

• Maximum speed: Mach 2.5+ (1,650+ mph, 2,650+ km/h)
• Combat radius: 800+ nm (720 nmi for stealth A/A mission)^[40] (920 miles (1,480 kilometres))
• Ferry range: 2,400 mi (2,100 nmi (3,900 km)) with conformal fuel tank and three external fuel tanks
• Service ceiling: 60,000 ft (18,200 m)
• Rate of climb: 50,000+ ft/min (254+ m/s)

Armament

• 1× 20 mm (0.787 in) M61 Vulcan 6-barreled Gatling cannon with 510 rounds of ammunition
• Four internal hardpoints in conformal weapons bays for low-observable capability, or
• External load the same as Strike Eagle's with standard CFTs, including targeting pods and additional external fuel tanks.^[41]

Avionics

• APG-82 active electronically scanned array (AESA) radar
• BAE Systems Digital Electronic warfare system (DEWS)
• Digital "Fly-by-Wire" Flight Control System (DFCS)
• Lockheed Martin Sniper advanced electro-optical targeting system and Infrared Search and Track (IRST) system
• Link-16 fighter data link

See also

Related development

• McDonnell Douglas F-15E Strike Eagle

Aircraft of comparable role, configuration and era

• Boeing F/A-18E/F Super Hornet
• Dassault Rafale
• Eurofighter Typhoon
• Lockheed Martin F-35 Lightning II
• Mikoyan MiG-35
• Shenyang J-11B
• Shenyang J-16
• Sukhoi Su-35BM

Related lists

• List of fighter aircraft
• List of military aircraft of the United States

References

Notes

Bibliography