15 years ago, Boeing presented to the world the F-15 Silent Eagle, a 'radar-invisible' version of the legendary old McDonnell Douglas fighter plane. With the promise of transforming the consolidated fighter jet into a more lethal aircraft compatible with modern aerial combat, the stealth Eagle ended up not being successful. However, its legacy still lives on in an even more capable version of the F-15.
The F-15SE emerged at a time when the only operational stealth fighter was the F-22 Raptor, still less than five years in service. The program of F-35 Lightning II – which would only come into operation 10 years later – was already experiencing delays, problems and budget overruns.
With this in mind and mainly seeking to meet the requirements of international customers (since the F-22 was banned from export by law), Boeing engineers returned to the drawings of the F-15, which made its first flight in 1972. Studying the project of the fighter, they made as many adaptations as possible to the aircraft's design to make it more 'invisible'.
In March 2009, the company presented the modified aircraft, based on the F-15E Strike Eagle fighter-bomber. Visually, the biggest difference was in the drifts, which were angled at 15º, improving aerodynamics and (theoretically) serving to 'deflect' radar waves.
The conformal fuel tanks (CFT), installed on the sides of the fuselage, were modified to serve as weapons bays, capable of internally carrying AIM-9 Sidewinder, AIM-120 AMRAAM missiles and JDAM and SDB (Small Diameter Bomb) bombs. The aircraft was displayed with the conformal bays (CWB) open, armed with a pair of AIM-120.
The aircraft should also receive RAM (Radar Absorbent Material) coating, to further reduce the radar signature. Inside, a complete revitalization of avionics, combat and self-defense systems. The would receive a panoramic screen and pilots would use the JHMCS II helmet with integrated display; the electronic warfare (EW) suite would be BAE Systems' Digital Electronic Warfare System (DEWS), which would work in conjunction with an AESA radar.
The F-15 Silent Eagle it would have about one-fifth the RCS of the original aircraft. An incredible feat, considering a project from the 1960s that had absolutely no stealth whatsoever. It is worth noting that a stealth aircraft already incorporates stealth characteristics in its design, complemented by the coating and EW systems.
This and a little more at a cost of approximately US$100 million, more than the F-35 but a better option that is cheaper to operate and introduce into service for customers who already operated the F-15. Boeing also planned modernization programs for existing aircraft.
And it was precisely from s of the F-15 that the 'new fighter' caught the attention. Boeing focused its offers on Japan, Israel, Saudi Arabia and South Korea. The Silent Eagle even participated in the South Koreans' FX Phase III Program, initially winning the dispute, but the F-35 ended up winning the contract.
Without any order, the Silent Eagle ended up being abandoned. The fighter never flew with the drifts 'lying down', being tested only in a wind tunnel. The modified CFT was flight tested with an F-15E prototype, firing an AMRAAM missile.
Although it was cancelled, the F-15SE was not forgotten and erased from history. The knowledge gained from the F-15 stealth project was applied to newer versions of the aircraft, such as the F-15SA and QA of Saudi Arabia and Qatar. These variants, in turn, served as the basis for the F-15EX Eagle II, the newest and most capable model of the fighter.
The F-15EX received the panoramic display, AESA radar, JHMCS II helmet, an even more capable EW suite, the AN/ALQ-250 Eagle ive Active Warning Survivability System (EPAWSS) and a mission computer that, according to Boeing, is the fastest in the world. Some improvements that were designed more than 10 years ago for the Silent Eagle.
The Eagle II will replace the older F-15C/D Eagle, while complementing the capabilities of the 22th generation F-35 and F-5 fighters. The US Air Force has ordered 104 aircraft, Israel has acquired 25 planes and Indonesia wants 24 units of the newest F-15.
With information Airforce Technology, Aviation Geek Club, National Interest
