The F-22 Raptor

The F-22 Raptor is combination of stealth, supercruise, maneuverability, and integrated avionics, coupled with improved supportability, represents an exponential leap in warfighting capabilities. The Raptor performs both air-to-air and air-to-ground missions allowing full realization of operational concepts vital to the 21st century Air Force.

F-22A Print
This print is available in multiple sizes from AircraftProfilePrints.com – CLICK HERE TO GET YOURS. F-22A Raptor 192nd Fighter Wing, 149th Fighter Squadron, FF/04-4082 – Langley AFB, VA – 2014

The F-22, a critical component of the Global Strike Task Force, is designed to project air dominance, rapidly and at great distances and defeat threats attempting to deny access to our nation’s Air Force, Army, Navy and Marine Corps. The F-22 cannot be matched by any known or projected fighter aircraft.

In short, the F-22 was designed to be a no compromise air to air killer that would be able to defeat anything in air to air combat. The cost was painful even for the US Air Force (USAF) as a result of this attitude. Other designs that are supposed to be much cheaper don’t have the same F-22’s all-aspect stealth let alone the same stealth from the rear.

The F-22 Uses Rectangular Exhaust Nozzles (and F-35, Su-57 and Chinese Stealth Fighters don’t), here’s why
F-35B

The F-22 exhaust nozzles

“The F-22 exhaust nozzles are very expensive and are the only exhausts to provide rearward stealth over a reasonable radar frequency range in a fighter plane,” Mark Knight, a pilot and an aviation expert, says on Quora. “To provide thrust vectoring using a circular nozzle would produce slightly more thrust from the same engine, but a circular nozzle would compromise the stealth of the F-22 from many rearward angles. Yes, the F-35 has a circular nozzle, and yes, it does compromise the stealth of the F-35 from some rear hemisphere angles. The philosophy with the F-35 design was to concentrate on forward hemisphere stealth and not to spend so much on rearward stealth. The F-35 still has reasonable rear hemisphere stealth, but it cannot come close to the F-22 in that regard.”

The F-22 Uses Rectangular Exhaust Nozzles (and F-35, Su-57 and Chinese Stealth Fighters don’t), here’s why
Su-57

The radar in fact will see the F-35 nozzle as a curved continuous surface which will generate specular reflections. “In a very narrow band of frequencies it is stealthy from the rear, but nowhere near as wide a range of frequencies as the F-22,” Knight explains.

“This is one of the most subtle problems that has to be solved in the stealth design world,” he points out. “The fact that radar systems don’t necessarily see the shape of the actual object, but their own version of the shape dependent upon the relationship between surface feature sizes, surface curvature and wavelength. As wavelength significantly exceeds surface feature size the feature effectively becomes rounded over to the radar and it will reflect as if the object was a different shape. That’s why the subtle curvature of the F-22 nozzle is better, because it is effective until much lower frequencies than the F-35 nozzle.”

J-20

Frontal stealth as a priority for Russian and Chinese Stealth Fighters

Knight continues. “The Su-57 was going to have F-22 style nozzles developed for it but once the engineers got started and discovered how expensive it was going to be the Russian government decided that the improved rear aspect stealth was not worth the extra cost. So, the Su-57 was developed with frontal stealth as a priority. The Chinese did not even consider such designs for their stealth fighters as front hemisphere stealth was all that they considered important.”

The F-22 Uses Rectangular Exhaust Nozzles (and F-35, Su-57 and Chinese Stealth Fighters don’t), here’s why

However, the rectangular exit port of the F-22 nozzle design is not the most important part of it from the point of view of its stealth. “The stealth comes from the pointed projections and the complex shape of the exterior parts of the nozzle. I have highlighted some of these features on the picture included [Below].”

Knight concludes: “These stealth considerations forced the cross section of the nozzle into the rectangular shape as a side effect. The exterior parts that provide the stealth are not rectangular but have a series of subtle curved and saw-toothed shapes that avoid reflecting radar energy back the way it came from a wide range of angles. This cannot work so well with a circular nozzle.”

F-22 Raptor model
This model is available from AirModels – CLICK HERE TO GET YOURS.

Photo credit: Mark Knight via Quora, Capt. Dale Greer / U.S. Air Force