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41

The canister contains a small parachute and either a spring or an explosive charge to kick the chute out when it is needed. It is a precaution for spin flight tests, that's why it is called a spin chute. See here for a video of the spin chute of the F-35. I guess now I should explain how a spin chute works. When an aircraft spins, it will rotate around a ...


27

It is a spin recovery/stabilization chute, installed during testing for high AoA test flights. The following image shows it being deployed on the ground. Image from fas.org


23

It's a Jet Fuel Starter (JFS) system, used by the F-16 and other jet fighters. On-board compressed air (called Stored Energy System) is released onto a turbine, which starts a small gas turbine engine, which then mechanically engages with the engine's gearbox to spin it. F-22 calls it Auxiliary Power Generation System. On the F-16 the JFS allows two bursts/...


22

First off, very rarely will you shoot at an unidentified aircraft. Most engagements require a visual ID, or a hostile action, prior to engagement. However, you will also program your aircraft with specific ROE logic that will indicate that certain aircraft are friendly, as identified by IFF transponders, Link 16, etc. You can still lock up friendly ...


19

ymb1 is right - stealth and not styling determine the looks of both the F-22 and the F-35. But there is more to it. Watch Lockheed test pilot Tom Morgenfeld talk about them in this video: The juicy bits are at 37:15' and at 43:35' into the video. Concerning the F-22 he says: Northrop built the F-23 exactly to what the Air ...


19

It certainly seems so. Stealth aircraft are not invisible to radar, only less visible. Under certain conditions the adversary will be able to get a radar lock: At close distance With very high (focused) radar energy At certain angles of incidence Given these risks and the low weight of chaff, it wouldn't be be wise to not carry it. One source that ...


17

This is a case of divergent design, and you can't know the answer without asking why current aircraft are designed they way they are. Following the work of Col. John Boyd in the 1960's in developing the 'Energy-Maneuverability Theory', the U.S. and allies primarily designed combat aircraft and tactics around the idea that an aircraft's specific energy state ...


17

In general, land based aircraft do not lend themselves well to carrier conversion. On the other hand, conversion in opposite direction is (relatively) easy, as shown by F-4 and F-18. Conversion of aircraft to carrier use require a number of modifications: Tail hook has to added and rear fuselage reinforced for arrested landings. Landing gear has to be ...


16

Circular nozzles have these advantages: They can be swiveled in any direction, so both pitch and yaw moments can be produced. Square nozzles only allow to create pitch forces, because their panels can only be moved around one axis. When moved differently in two-engined aircraft, limited roll moments are also possible. Round nozzles are lighter. As long as ...


15

The edgy—no pun intended—looks are an example of form following function. The F-22 and F-35 are stealth aircraft, the edges (flat surfaces, sharp angles) help deflect the enemy's radar so they remain undetected. Modern stealth aircraft first became possible when Denys Overholser, a mathematician working for Lockheed Aircraft during the 1970s, adopted a ...


14

Part 1 - TVC Perception The US also ran several programs with TVC: F-15 STOL/MTD and ACTIVE. F-16 VISTA / MATV. AVEN: F-18 HARV (High Alpha Research Vehicle). Overview pdf. F-22 (almost 200 produced) X-31. X-36. (Yaw only.) X-44 MANTA (proposed F-22 variant) (All photos from their respective wiki pages except ...


12

For military aircraft on "alert", there is a position called cocked on (or as some news sites call it, "hot-cocked"). This procedure is run before the aircraft is placed on alert, and does a pre-flight check of all the instruments and then places them in a state that allows power application in a rapid manner. This way, only minimal steps are required for ...


11

The wing design is different between F-16 and F-22 (which is similar to YF-23) because the requirements were different. The wing of F-22 (and that of F-23) were designed with stealth in mind, with the wing (and control surface) edges parallel to each other. There was no such design requirement in case of F16. F-16 is a highly maneuverable aircraft in its ...


8

The rudders on modern fighters are canted mostly to reduce their radar cross section. A straight vertical tail would produce a corner reflector in combination with the fuselage or the wing and would send radar waves straight back to their source. To reduce the detection radius, such a behavior must be avoided. The first aircraft to use this trick was the SR-...


8

They're very different aircraft, built to different requirements, meant to fill very different roles. Large tails are good for pitch authority and high-alpha---which are good for maneuvering and dogfighting, but not very relevant to the F-117's missions. The F-117 was a medium-altitude, tactical bomber that spent its life trucking around a pair of large, ...


8

The jet uses a fixed, rhombohedral shaped jet intake combined with a serpentine intake duct. It allows for speeds just north of Mach 2 without the need for a variable geometry inlet to prevent shockwave ingestion.


6

The appearance of being closed/open is a light trick; light reflecting off the tiny transparent window of the missile launch detector. This detector typically sees in IR and would detect the plume of a heat-seeking missile. According to Wikipedia, the model used on the F-22 is AN/AAR-56 (IR based). (There are videos available on YouTube for its output; ...


6

Aerodynamic heating will damage or destroy the composite wing of the F-22, especially around the leading edge where compression heating is highest. See here for the temperatures which supersonic flight causes. Therefore, the F-22 has been restricted to Mach 1.8 for short duration and Mach 1.6 for prolonged flight. More speed will not be needed, anyway. The ...


5

The afterburner is aft of the gas core of the engine in the jet pipe and bypass air from the fan would have already been mixed with the exhaust gases from the core prior to passing through the afterburner flame holders. Supercruise is by definition supersonic cruise flight without the use of afterburning, so augmentation would not be in use here Counter ...


5

In order to reduce the radar cross section (RCS) of the aircraft, the F22 canopies are coated with a thin layer of Indium Tin Oxide (ITO), which gives it a golden tint. From the book F-22 Raptor by Bill Sweetman: The F22 Raptor canopy ... comprises two sheets of polycarbonate, sandwiched between two layers of optical glass, fusion bonded in an autoclave ...


5

Those flaps on exhaust are for thrust vectoring. A simple definition would be: the ability of an aircraft [...] to manipulate the direction of the thrust [...] to control the attitude [...] of the vehicle F-22 uses it like this: [Its] nozzle [...] is the first vectoring nozzle. That means the pilot can move, or vector, the nozzle up and down by 20 ...


5

The F-22 was developed in the 90's, primarily for use by the United States Air Force. This means it was designed to serve specific mission profiles. The F-35 however is going to replace the F-22 and serve all the air branches of the US Military. This means that it needed a broader mission profile. The last F-22 delivery was in 2016. For the F-22 Raptor: ...


4

let's say a friendly aircraft were to fly in front of you when you had sight lock turned on; would the missile fire at the friendly aircraft, or is there a piece of technology in the friendly aircraft which registers that it's with you? There is indeed an important piece of technology which "registers that with you". The piece of technology is called an ...


4

The design philosophy of the F-117 was different from that of the F-22 (or F-18, which was not intended to be a stealth aircraft). The main design driver of the F-117 (in fact, practically the only one) was to reduce the RCS- the result being a distinctly non-aerodynamic design. The inclusion of separate horizontal stabilizers would've reduced the ...


4

Adding to the above answer: These mechanical devises are for thrust vectoring. Their purpose is for super-maneuverability, meaning that the aircraft can maintain pitch and yaw control at extreme angles of attack where other non super-maneuverable aircraft would stall, spin, completely loose control, etc. This ultimately allows a wider flight envelope ...


4

A very important reason is stagnation. US aircraft development has pretty much stopped cold in the mid-late 1980s, with just the F-22 and F-35 entering production since, and those decades overdue. Meanwhile, the Soviets created and fielded all the types you mention. At the time the current operational generation of US aircraft entered service, TV simply ...


4

The inlet spike is not required for supersonic flight, it is just one way to minimize the losses that comes with decelerating supersonic flow. As a general rule, the shallower angle that you force the flow to turn at supersonic speeds, the weaker the shock wave that will form at turn, and the lower the loss (in total pressure) will be. This is why the planes ...


3

No, the F-22 has an Allied Signal APU in the port wing root opposite of the cannon installation, which is on the starboard wing root. From GlobalSecurity.org (http://www.globalsecurity.org/military/systems/aircraft/f-22-fcas.htm) Auxiliary Power Generation System (APGS) The Auxiliary Power Generation System (APGS) for the F-22 is being developed, built, ...


3

The type of nozzle used in the aircraft depends on the design decisions taken. In short, the designers of F-22 chose stealth over manuverability, while the Sukhoi PAK FA designers went the other way around. Circular thrust vectoring nozzles have been used in Sukoi aircraft for quite some time. The main advantages and disadvantages of the two types of thrust ...


2

You can start an f-22 in about 2 minutes or less. The procedure is Master Batt. APU(Auxiliary Power Unit) Flip 2 generator switches flip nav and position lights as required for mission Make sure fuel switches are set right Wait a couple seconds for APU to finish start up push throttles to idle configure MFDs as needed as engines spin up. taxi to ...


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