The United States Air Force boasts some of the best fighter jets in the world including the star stealth fighter duo, F-22 Raptor, and F-35 Lightning II, as well as the globally popular F-16 Fighting Falcon and F-15 Eagle.
The Boeing F-15, which entered service in 1976, has been modernized to maintain its relevance in the 21 century, with several modifications like the F-15 Strike Eagle and the latest F-15EX, to name a few.
It is indeed one of the most successful and combat-proven jets in the American and Israeli arsenal. In aerial combat, it has a staggering 100 confirmed kills and zero losses.
In an earlier report by The EurAsian Times, a USAF pilot had admitted that the ‘mighty’ F-22 Raptors would avoid a dogfight with Sukhoi Su-35 jets and instead call on the F-15 fighters to tackle the Russian threats.
Recently, a batch of F-15C and F-15D fighter planes from the United States Air Force arrived in Poland recently on a mission to “improve NATO’s collective defense posture” and assist the region’s permanent Baltic Air Policing (BAP) mission. This is indicative of the faith reposed even in these aging variants of the F-15 that are nearing retirement.
The newer models of the F-15 have more durable airframes, powerful CPUs, and improved flight control systems. The latest F-15EX is equipped with improved radar and other USAF-exclusive components. It may also see itself deployed as a possible standoff platform in conjunction with the F-22 Raptor, as previously stated by the EurAsian Times.
Among American jets, the F-15EX is regarded as one of the best dogfighters. The F-35 and F-15EX planes, according to Air Force Magazine, cost roughly $80 million each. While the former is famed for its stealth, the latter has more firepower and is capable of flying higher, further, and faster.
In support of the F-35 fighter jet, the F-15EX may carry a large number of missiles and deliver firepower to eliminate targets detected by the F-35 during offensive operations.
The F-35 is referred to as a “battlefield quarterback” by the US Air Force, as it can track incoming threats while the F-15EX can remove them. The ultimate combat jet in the US inventory, the F-15, stands distinguished by its offensive capability, its ability to carry a heavy payload as compared to its stealth counterparts, and its agility and ground-strike capability on the battlefield.
The aircraft still remains in great demand in countries around the world, even the ones that have already purchased the F-35. For example, despite possessing the F-35I, the Israel Air Force is reportedly seeking the advanced version of the F-15 Eagle from the United States.
On the other hand, while Japan is the country with the most F-35s in its Self Defense Air Force outside of the US, it has signed an agreement for upgrading its F-15s with the most advanced systems.
The flyover by the Air National Guard at Fenway. Always great.
— Josh Brogadir (@JoshBrogadirTV) April 2, 2021
While this aircraft has seen several upgrades over the years, there was one variant that could have trumped even the F-22 Raptor, touted as the world’s most powerful air superiority fighter. The fact is that it was never allowed to see the light of the day.
The F-15 Variant That Never Took Off
The original F-15 Eagle was created as an air superiority fighter. “Not a Pound for air-to-ground” was the slogan during the F-15’s development, and it worked. Until the creation of the F-22 Raptor, the F-15 was the best dogfighter in the world.
The Eagle’s huge, hefty structure, two-seater feature, and powerful engines, made a multi-role F-15 an appealing possibility. This is how the F-15E Strike Eagle or the F-15EX ‘Eagle II’ were born; the latter was inducted into the US Air Force last year.
In fact, focusing on the potential of the F-15 aircraft, Boeing even converted the Eagle into a stealth version. Over 35 years after the maiden flight of the F-15, Boeing debuted the F-15SE ‘Silent Eagle’ in March 2009.
The Silent Eagle was created primarily for export to international customers as an alternative to the F-35 Lightning II stealth fighter. It is an enhanced version of the F-15E Strike Eagle variant. The demonstrator plane was built from a first-generation F-15E and flew for the first time in July 2010.
The F-15SE shared the same fundamental design as the F-15E. However, new components were introduced to achieve stealth performance. A conformal weapons bay (CWB) and fuel tanks were among them, according to Business Insider.
Boeing reduced the aircraft’s radar cross-section (visibility on an enemy radar) by incorporating these modules into the airframe. The CWB also had the added benefit of expanding the Silent Eagle’s internal carrying capacity by four air-to-air missiles.
The tail of the aircraft was altered to create the F-15SE. On the Silent Eagle, the Eagle’s famous twin vertical stabilizers were canted outwards by 15 degrees. The aircraft received more rear lift as a result of this angle while using less weight. Overall, the aircraft’s range was expanded by 75 to 100 nautical miles.
Two General Electric F110-GE-129 turbofan engines with a thrust of 29,000lbs or two Pratt & Whitney F 100-PW-229 engines with a thrust of 29,000lbs were planned for the F-15SE.
The F-15SE was to be equipped with air-to-air missiles like the AIM-120 and AIM-9, as well as air-to-ground weapons like JDAM and globules admire. The F-15SE could reach a top speed of 2,655 kilometers per hour. It could also climb at a pace of 15,240 meters per minute.
The Silent Eagle’s radar signal was further reduced with a specific coating on some components. The aircraft was planned to be a stealth fighter jet, although it could be converted to a non-stealth aircraft if necessary.
The CWB and fuel tanks on the F-15SE could be removed and replaced with non-conformal modules depending on mission needs. The F-15SE became more adaptable as a result of the end user’s flexibility to alter the aircraft as needed.
The Silent Eagle was pitched to Saudi Arabia, Israel, Japan, and South Korea after successful wind tunnel tests in 2012.
Saudi Arabia chose the traditional F-15/C/D/SA Eagle fighters, while the rest of the world chose the F-35. As of today, F-35 is the most popular stealth fighter in the world that has seen a consistent trajectory in its sales over the years, according to Business Insider.
Why ‘F-15 Stealth’ Didn’t Succeed?
But the question is why this F-15 variant did not pique the interest of air forces. The primary reason seems to be the fact that there’s a significant performance gap between the quasi-stealthy and a stealth plane.
“This is because for every order of magnitude (factor of ten) RCS decreases by, detection range decreases only by 43.7 percent. Thus a 1 m2 RCS will not be detected at one-tenth the distance that a 10 m2 RCS will, but something more like three-fifths the distance. That’s why true stealth jets like the F-22 and F-35s have had their cross-sections reduced to around the size of a golf ball and a marble: .001 to .0001 m2,” according to a previous report of the National Interest
“An F-15SE is thought to have a cross-section comparable to the Super Hornet with possibly a .1 m2 cross-section from the front and 1 or higher from other angles. This is a useful edge — but not a decisive one,” it said.
The F-15SE was developed primarily for export purposes. However, most countries that were being offered the aircraft decided to buy an actual stealth fighter, like the F-35, instead of a refurbished one that had certain stealth components.
For example, the Silent Eagle was offered by Boeing for roughly $100 million each plane, but South Korea ultimately decided to spend up to $176.5 million per F-35 to have 40 fully stealth jets.
The high cost coupled with less than stealthy characteristics led to this Silent Eagle being shelved due to a dearth of buyers. However, the F-15 still remains the best dogfighter in the American fleet and the creation of the Silent Eagle revealed its adaptability and confirmed its importance in the 21st century.