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23

The F-22 is intended (and the competing YF-23 was intended) to be an air superiority fighter to replace the F-15. The F-15 was a twin-engine model, as was the F-4 Phantom that it replaced. Twin engine planes have excellent "survivability," meaning they can take a lot of hits and still stand a chance of making it home (you can lose an entire engine and ...


21

The purpose of the roll posts is to let the pilot have some control authority in hover and stabilization, along with controlling aircraft attitude. Basically, the Rolls Royce Lift System used in the VTOL F-35 has three components connected by drive shaft (along with the engine): The LiftFan at the front Three-bearing swivel module (3BSM), which turns the ...


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 ...


18

Stealth. The F-35's nozzle is designed in that manner to reduce the IR and radar emissions from the aircraft (sometimes called Low Observable Axisymmetric Nozzle (LOAN)). From the press release which announced the test results: GE Aircraft Engines' new LO Axi (Low Observable Axisymmetric) Exhaust System was successfully tested recently ... testing being ...


16

To try and change lift by changing fan blade speed would be too slow to modify the lift for "tiny" and "delicate" changes in how the plane hovers. Like a helicopter, the F-35 is able to maneuver in very small movements and change very fast (in fact likely better than a helicopter). So the pilot can "nod" to you, and move around ...


15

The answer to both of your questions lies in the vertical takeoff and landing (VTOL) capability of the F-35. In order to provide vertical thrust, the rear part of the engine rotates downward. This is much easier to accomplish if the engine exhaust is not kept on top of the plane, as in your YF-23 example. This rotating ability is also much easier to ...


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 ...


15

Your assumptions (constant thrust for both lift fan and exhaust) are wrong. From wikipedia: "For pitch control, the areas of exhaust nozzle and LiftFan inlet are varied conversely to change the balance between them while maintaining their sum, and with constant turbine speed" So yes, the thrust is modulated to accomplish this.


13

I would like to make some general comments, as having worked on programs stood up to build sensors for various military threats. In these programs we were always attempting to get data on relevant threats. The more challenging the signature the more it drove the sensor technology, hinting at areas of improvement. In the sensor research we often met with the ...


12

From what is available on the internet, the F35B's lift fan is more than just a simple shrouded fan. There is at least some variable guide vanes functioning as nozzle. So to answer your question, no, the lift from front and back seem to be completely (lift fan by variable guide vanes, engine nozzle by, well, a variable nozzle) adjustable.


9

No, it cannot, at least there is no reason for it to do so... A) The stick while in "hover mode" does not control the pitch/roll of the aircraft, but the forward/lateral position of the aircraft. This means that the aircraft can only shoot forward in a level attitude, it can't pitch up/down to hit a target. B) When in "hover" mode, the landing gear are ...


9

The F-35 has what is called the Rolls-Royce LiftSystem. This Contains one lift fan in the middle of the aircraft, and a rotating jet exhaust to provide vertical thrust, and two rotating nozzles to provide stability. The pilot pushes a button, and doors on the aircraft open for the lift fan, while the exhaust nozzle rotates downward. The pilot controls the ...


9

There is no major problem to be solved by moving the cockpit inside. The canopy adds minimal drag, considering how much drag the whole of a fighter's airframe produces. It also offers the highest quality of vision. To expand on the latter, let's define a few items that go into visual quality: Field of view Acuity, including in motion Noise Dynamic range ...


8

Why does the F-35 have only one engine unlike the older models The USMC wanted the aircraft to have S/VTOL capability. This meant that the aircraft should have a single large engine as the best configuration would be to have a single engine with swiveling nozzle aft of center of gravity for supersonic flight. Having multiple engines in a VTOL aircraft is ...


8

The F-35 is a plane that relies on safety via stealth, rather than armor. The F-35 fuselage can be dented much like any other plane. The F-35 uses a variety of methods to reduce the its radar signature, most of which revolve around the "skin" of the fuselage - the way the fuselage is physically shaped is meant to reduce the reflection of radar, and there are ...


8

With very select exceptions like the Su-34, and the A-10 if you consider it modern, they are not. Even in these cases only the pilot and a few critical parts are armored. Most of the aircraft's skin offers no meaningful resistance even to small arms. Extensive armor coverage that could withstand modern air-to-air or surface-to-air weapons simply isn't ...


7

3-4 seconds may lead to a detection, but then again 1-2 seconds could too with a sophisticated radar system. The important thing is that 3-4 seconds is short enough that a detection would be extremely hard to exploit; by the time a missile could be launched the contact would have disappeared. If by some chance a station managed to get a missile off in that ...


6

The most probable reason is because of commonality, to reduce costs and support logistics. But, it also increases operational flexibility. The UK MOD want to operate them off the Queen Elizabeth carriers, and they do not have a catapult launch, but a ski jump. Only the B version can get airborne with this setup. So, the RAF had to go with the B version also. ...


6

As to the first question, it appears as fuel cooling of electronic components and other equipment is integral in the F-35 design, all branches of the armed services will not be able to remedy this problem and it will have to be solved with only fueling the aircraft with cold fuel. The Air Force has opted to use fuel trucks painted white in order to keep ...


6

Those are Luneberg Reflectors. They enhance the radar cross section of the aircraft. For two reasons; to be more safe around civilian traffic due to being easier spotted by traffic control radars, and where they do not want adversaries to train their radar systems on it to gain knowledge of its strengths and weaknesses. Not sure if those on the picture is ...


6

Unless you can have a continuous display over the entire field of vision WITH fail-safes I dont think it'll ever happen. Anything less will either require transitioning from one display(screen) to another or from display to display. If you've ever used a car GPS you will know the lag in shifting from the in-car display to outside view. Mark 1 eyeball is ...


6

In addition to all the other reasons: Every camera-to-screen system has lag. Lag in a dogfight can be fatal. There will be some distortion between the camera and the screen, no matter how well designed. Distortion can be fatal too. Cameras and screen cannot reproduce depth perception (yes there are ways to do it but they are a LOT more complicated than ...


5

The F35's skin consists of a/several composite(s). Although it's obviously classified, I suspect the main reason it's chosen has something to do with stealth rather than strength. Interestingly, there seem to be more information about the F22 than F35, which is supposed to be, err, more secretive? For example, the F22's airframe bulkheads and twin booms are ...


5

"Modern fighter jet" and "F-35" are not synonymous. The F-35 is just one out of 20-30 fighter jets currently in full-scale production (depending on how you define "full-scale"), and it's not representative of the rest of them at all. The majority of fighter jets have their skin made out of aluminum, of about the same thickness or a little thinner than on ...


5

It was due to flow issues. Here's an excerpt form Air & Space Magazine We discovered a few things that would need to change before the aircraft entered production. On the X-35B’s STOVL variant, the doors above the lift fan had a bi-fold arrangement: They folded and slid outward, creating an opening for air to enter the fan. However, when the ...


4

Simple answers: First stealth means two things: 1. Reduced Radar Cross Section (RCS) or reflective target as might be detected by primary radars. Primary radars are ones which rely on reflected energy (as opposed to transponders). And, 2. Stealth also implements other passive and active measures. The passive ones include reducing ALL emissions from the ...


4

the F35 has a ton of electronics that the Harrier could only dream about, but I will focus on propulsion differences. The biggest is that the F35B uses a separate lift fan in front of the engine, oriented to provide vertical lift that balances the vectored thrust from the rear of the engine. The lift fan is disconnected when flight speed is obtained and ...


4

Traditionally many single seater aircraft have had nuclear weapons capabilities. To name a few: A-4 F-104 F-105 F-84 F-16 A-7 (I think) F-102 F-106 F-88 F-101 This list isn't exhaustive. The release of the weapon will typically be authorised before takeoff, the pilot then having the electronics on board to enter the final arming codes that will bring ...


4

The human eye is 576 Megapixels. When a helmet mounted "virtual reality" type of helmet display comes out some day, in conjunction with cameras and hardware that can record and process at that resolution, then you might see a canopy-less fighter. By that time, the pilot will be software, or at minimum, located remotely anyway.


3

The answer is yes. The damage done and to what extent the airplane’s RCS was compromised depends on the type of bird that hit, the location of the hit, the speed at which the impact took place and the total damage done. Birdstrike can puncture holes in airframes, shatter canopies, damage engines and wreak all kinds of havoc. If this compromises the shape ...


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