Why are stealth plane undetactable by radar?

Question

And why they're always black?

Answer 1

they're undetected from radar because they're made of bubble gum so they absorb the radio waves instead of bouncing it. this was the joke yesterday i had to tell to a nephew but answerer no.1 says it all and its true.

Answer 2

Because their shape deflects most of the radar energy away from the receiver, because their paint is formulated with RF absorbing material, in some cases, the skin is backed by dummy loads that can be deactivated while flying in an area where they WANT to be tracked.  Black is harder to see at night and reduces glare during the day.

Answer 3

There aren't undetectable, they are just very hard to detect.

There are three reasons:

1- Shape.  Either angular, or smoothly contoured.  Radar works by receiving energy bounced off a target-I'm sure you knew that.  But the energy coming back needs to be almost exactly 180 degrees out from the energy coming to get a good return.  If one can design angles that disperse the energy equally in different directions, that's less signal that gets back to the receiver.

2- Material.  Radar-Absorbent-Material  is exactly what the name implies, the outer covering of the aircraft doesn't reflect that radar energy back.  The canopies are also laced with RAM-otherwise they would be a fairly significant radar reflector.

Combining 1 & 2 gives one radar energy absorbed AND dispersed.  Making it difficult, but NOT impossible to find via radar.

3- They are black both because that's the color the material extrudes in (paint would actually reduce the RAM effectiveness), and to help reduce IR and visual signatures.

IR signature is not just from the engines, the canopy and leading edges also absorb and generate heat.  

Hope that helps.

Answer 4

Stealth Aircraft are hard to detect but the preflight intelligence which allows the flight plan to avoid significant radar threats is important too.

They can be detected, I believe that there was a problem with the B2 being quite visible when flying in rain.

Answer 5

They are black so they are harder to spot at night (when they are mostly used). They avoid being spotted by radar due to their geometry which doesn't allow the waves to bounce back to the sending radar.

Answer 6

Black is the F-117. Used at night. First generation and being retired already in spite of the Darth Vader looks. Geometry was used in it. Now its more materials and coatings. Overall smoothness is important. One protruding fastener head can increase the radar signature dramatically and the F-22 and new F-35 are conventional looking fighters that are stealth aircraft and the most capable fighter planes ever built....Materials used can absorb radar waves and embedded engines avoid heat signatures and radar both. And the F-22 and F-35 can defend themselves, nothing in the world currently flying wants to mix it up with an F-22 and a good pilot. The F-35 is about as good.....High speed has nothing to do with it, the F-117 is very slow in todays terms and if caught it is a sitting duck for a conventional fighter. The F-22 is still having capabilities added but in war games in Alaska a year ago it scored an 80 to 1 kill ratio. The one loss was when an F-16 by accident broke out right on ones tail.....By the way, even an F-16 has a radar return about the size of a golf ball.

Answer 7

1) Their shape - geometrically designed to deflect/reflect radar waves in a random manner (scatter them). This reduces the returns to the tracking radar.

2) Use of absorbent material, coatings and finishes. These absorb radar waves and prevent a lot of them going back to the source.

3) Excellent high speed, low flying and terrain hugging characteristics, thereby giving the radars very little time to lock onto the aircraft.

4) On board counter measures, including electronic.

5) Black - it is the most absorbent colour. It helps absorb the radar waves, and also makes the aircraft invisible at night.

The above, in a nut-shell (in layman's language), answers your question.

Answer 8

Stealth Aircraft are made of R.A.M. Radar Absorbing Material. It is a special material that absorbs the radar wave instead of reflecting the wave back to the radar reciever. They are also black so that they can be hard to see at night...virtually impossible. Therefore, R.A.M. and black. equals a very sneaky sneaky plane.