Questions tagged [radar]

Radar is a surveillance technology that uses radio waves to determine the range (and azimuth) of an aircraft. It works by measuring the time difference between a radio transmission and the echo or reply to that transmission. Radars are the most common surveillance equipment used by ATC.

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An Aircraft is a flight level 150 the DME is at sea level find maximum and minimum range?

I have taken this question from keith williams book. I know that we can find the maximum range of DME by line of sight formula which is R=1.23(Ht + Hr). But I don't know how to determine it's minimum ...
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Why is MH370's location data from the Malaysian military considered reliable if the altitude data isn't?

This is another question originating from the video "The Vanishing of Flight 370", by Lemmino. At 13:52 he says The data recorded by the Malaysian military ...
Purple P's user avatar
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Could the radar on a passenger plane be used as a makeshift AWACS?

I'm aware that an airliner doesn't have a way to transmit data over datalink, but could an airliner at least tell other aircraft what they see on radar? Is an airliners radar powerful enough? (Source ...
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What protections does the designation for aeronautical spectrum provide?

Stated differently: As an aviator, what benefits do I receive from the radio frequencies used by my avionics and ATC being designated "aeronautical protected spectrum" as opposed to just ...
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What is the purpose of MCP/FCU and FMS selecte altitude?

in Radar Mode S Asterix message, the Mode S Enhanced Surveillance (EHS) provides FMS Selected Altitude. MCP/FCU Selected Altitude. What is their purpose? What is the differnte between FMS and MCP/...
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Can doppler radar be used to detect stealth aircraft by focusing on the characteristic flow field instead of the aircraft itself?

Any aircraft traversing through the air would impart velocity, pressure, and temperature gradients to the surrounding air, then there are some phenomenon which are unique to all winged bodies such as ...
Tony Stark's user avatar
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Why are only discrete SSR codes allotted for aircraft identification?

What happens if we assign a non-discrete squawk code (ending on 00) like 0200? Is there any particular reason for non-discrete squawk codes to be used only for special purposes and not for ...
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Is the F-117 actually inferior in its RCS than the F-22 and B-2?

This might seem like a purely opinionated thing, but bear with me. I think there is some general statement to be made here not based on guesswork. Question: Is the F-117 actually inferior in its RCS (...
AlphaCentauri's user avatar
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What is the N001VEP symbology in the Su-27SM?

I saw on Wikipedia that the N001VEP radar in the Su-27SM can track 10 targets at a time and engage 4 of them at a time. So, what is the symbology of the N001VEP in the Su-27SM that allows it to do ...
JustACoder's user avatar
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Who are the audience of ADS-B?

If an aircraft has only Mode-A xpdr, then ATC with the help of Primary radar (for Position determination) and secondary radar (for receiving squawk), places a blip(only squawk code/callsign, position-...
Krishna Kanth's user avatar
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What is the difference between RTCA and EUROCAE standardisation?

We know that RTCA and EUROCAE working to develop standards for international civil aviation (air surveillance systems) My questions are: Do RTCA and EUROCAE work together for air surveillance ...
Uniform's user avatar
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How conductive is Carbon fibre in aircraft skins?

I ask this question in relation to radar cross section returns, Are the EM reflection properties of carbon epoxy composites similar to aluminum? Also how well are EM shielding characteristics of CF ...
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If ADS-B is on majority of aircraft, why don't we start seeing ASR dying out?

Are radars still needed, or will radars start coming down soon?
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How does the secondary surveillance radar calculate the aircraft velocity?

In radar surveillances systems we have PSR ( primary surveillance radar) and SSR ( secondary surveillance radar) And they provide informations to be use it by air traffic controller, one of these ...
Uniform's user avatar
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Aside from primary radar, how did ATC monitor planes' locations before ADS-B? [duplicate]

From what I understand, air traffic controllers can monitor planes with radar, often called primary radar, or with ADS-B. I've seen ADS-B called "secondary radar," although it isn't really ...
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Radar fuel level sensor

Do any aircraft use radar to measure the level of fuel in their fuel tanks?
Wail Saifaldeen's user avatar
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Why does secondary surveillance radar use a different antenna design than primary radar?

In radar surveillance we use primary and secondary surveillance radar for different purposes. I'm wondering about the antenna that use in both system: Secondary Radar uses an array antenna Primary ...
Uniform's user avatar
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What are the terrain-following radar modes of the B1-B?

The Rockwell B-1 Lancer is a supersonic-capable variable-sweep wing large bomber operated by the US Air Force. One of its "key features" is terrain-following radar and a fast, heavily-...
Landak's user avatar
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Can fake air defence radars be built to fool anti radiation missiles? [closed]

Running air defence radar can be a dangerous business because of anti radiation missiles like AGM-88. Radar operators learned to switch radar of trying to prevent hits. Missiles were upgraded to ...
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Is there a VFR mobile app that shows other aircraft in real time?

In the UK, are there any apps available that show a real time radar / GPS of other aircraft and ideally their callsign? As I fly Microlights, I only fly VFR, but in a high wing and often with low ...
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Why does the B2 bomber's trailing edge sawtooth shape negatively effect its stealth characteristics?

I read an article about how the new B21 would have (in theory) a W shaped trailing edge, which was the initial shape intended for the B2 before the gust alleviation system was added to the ...
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Are there reasons why hypersonic missiles can't be seen on radar? [closed]

military.com claims that hypersonic missiles cannot be seen on radar: And it's so fast that the air pressure in front of the weapon forms a plasma cloud as it moves, absorbing radio waves and making ...
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Two low flying large planes made bank turn - not on radar [closed]

On Thursday March 10, 2022, at approx. 7:30pm in Monroe, Connecticut, I witnessed two full sized planes following one another extremely low and then make an incredible bank turn. These planes did not ...
Tattoo Kt's user avatar
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From what distance can a man hear and see an airplane flying overhead, without any equipments?

Suppose I stand at p = (latitude,longitude) on earth. I want to manually check for any airplane flying overhead in my neighborhood with naked eye and without any ...
Zeta.Investigator's user avatar
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What is the reason behind updating the radar tracks on the CWP in chunks instead of updating them all at once?

Some time ago, I noticed that the controller's screen (CWP) of a particular system in a European ACC. was not updating all the visible tracks at once but it was following this pattern: The screen ...
Stelios Adamantidis's user avatar
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What is the minimum and maximum altitude reading for the average radar altimeter?

The valid range for latitude is -90 to 90 degrees. The valid range for longitude is -180 to ...
lolololol ol's user avatar
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1 answer
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Why does the MVA have 1000 ft height buffer?

As per definition the Minimum Vectoring Altitude (MVA) in each sector provides 1000 ft above the highest obstruction [...]. I am curious where these 1000 ft stem from. Why not 500 ft? Why not 300 ft,...
Erik's user avatar
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Can military radar detect all civilians aircraft at inflight altitudes regardless of transponder status?

Not the same as this one Can radars detect all planes, including military ones? because it implies civilian radar systems. Simply military radar systems must be able to detect all civilians aircraft ...
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What is the significance of radar cross section (RCS) for air defense?

From the internet or any other medium of information I came to know that some cutting edge stealth aircraft have radar cross sections of a bird (or something similarly small). I don't have the in ...
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Can single engine/smaller aircraft turn off ADS-B?

I was just looking at the adsbexchange website, and was wondering if it was possible for smaller, private aircraft to turn off their ADS-B? I was wondering this because id figure that maybe not ...
Obama. The real obama.'s user avatar
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Does 'RADAR' include MLAT or ADS-B, etc?

Nowadays, There are many surveillance systems other than PSR or SSR, such as ADS-B or MLAT, etc. And ATC system such as ARTS uses various surveillance sensors including ADS-B to indicate track for ...
Min's user avatar
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18 votes
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What is that airport equipment that looks like an SMR but rotates like a windmill?

— YouTube The one rotating horizontally looks like a standard Surface Movement Radar (SMR). But the one next it, rotating vertically (like a windmill or wind turbine), what is that? Wouldn't that be ...
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4 votes
1 answer
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Can pretty much anyone run/operate a primary radar? [closed]

Thinking about increasing the amount of information one receives beyond that from one's own 1090 MHz ADS-B in receiver when following aircraft as a hobby, is it perceivable and possible to operate a ...
Martin's user avatar
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11 votes
2 answers
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Did WWII fighters do a roll before engaging to identify themselves to radar operators?

There's some folklore in the radar world about the Nazi fighters doing a roll before engagement to mark them to a German radar operator. This makes a lot of sense because it allows you to change your ...
b degnan's user avatar
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29 votes
5 answers
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How is radar used to help aiming a gun on fighter jets?

I know gatling gun is fixed mounted to the airframe of the plane, thus cannot be rotated left/ right or up/down. However watching DCS pilots dogfighting with opponents they sometimes mention their ...
svizko's user avatar
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4 answers
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What type of chart is displayed on ATC radar screens?

I am looking to make an emulation of the radar screen familiar to Air Traffic Controllers, such as the pictures below. I have been having a very hard time finding what type of chart/map is being used. ...
Zero's user avatar
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6 votes
2 answers
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What causes the radar phenomenon of ‘far-shore brightening’?

In Larry Milberry’s text on CAE (Canadian Aviation Electronics), in a discussion of the development of digital radar land mass simulation (DRLMS) for the Dutch Lynx mission simulator, far-shore ...
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How do Luneberg lenses hide a stealth aircraft's real signature?

I thought aircraft was supposed to be stealth and not show up on radar under the right conditions. This article says Removable Luneburg lens type radar reflectors are sometimes attached to military ...
Nederealm's user avatar
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Tail Warning Radar on the P-51

One of the "features" of the P-51 was a tail warning radar that was supposed to let pilots know if an enemy fighter was on your tail. However, a P-51 pilot told me that they generally ...
Phil Crowther's user avatar
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1 answer
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Why does a radar altimeter show negative values on the ground?

This applies to the Airbus 320 or Boeing 737, among others: Although it is useless on ground, the radar altimeter will repeatedly display a value (including negative) for a specific runway and airport ...
Sniper's user avatar
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1 answer
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Why bits are mixed up (interleaved) during ATC transponder mode A and mode C reply format?

In the image above from radartutorial.eu, we can see that the sequence of bits are c1 a1 c2 a2 c4 a4 during the reply of ATC transponder mode A. Why are the bits not transmitted like c1 c2 c4 then a1 ...
Tough questions's user avatar
1 vote
1 answer
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Is it possible to use multiple primary radars to determine an object's location in three-dimensional space?

My question is this: if, for example, I have multiple radars across an area, tracking a particular airborne object, can I use the returns from the radars to determine the geographical location of an ...
Sagi zawi's user avatar
1 vote
1 answer
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Weapon vs normal aircraft track

I've read that some radars can detect stealth aircraft or aircraft with low radar cross section but are not powerful enough to allow a "weapons" track or allow a missile or another aircraft ...
Nederealm's user avatar
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10 votes
2 answers
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How does the F-22 Raptor radar reflector work?

The F-22 Raptor (and other stealth aircraft) can be made more visible to radar by using radar reflectors, or in other words, radar cross section (RCS) enhancers. In the comments section of this answer ...
Jpe61's user avatar
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Do jetliners carry radar that can detect other aircraft?

If not, why not? For example, if a civilian jetliner is flying at night over the Ocean, or a remote area with no airports/ground radar stations, and another airplane is also heading towards it on a ...
Mr X's user avatar
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How are both squawk and altitude transmited when operating a Transponder in Mode C?

I know that in Mode $3$ (which includes Mode A and Mode C) the aircraft transmits $12$ information pulses. That corresponds to $2^{12}=4096$ squawk combinations in Mode A which are sent to ATC to ...
Darjan's user avatar
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5 votes
1 answer
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What is this part on the Me 262?

I have seen this part on a me 262 model kit but I don't know what it is... I've make some research on it but I find nothing! Maybe it can be radar, or a weapon? Do you know what is this? And also its ...
L'aviateur's user avatar
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How will the update from DO-260A to DO-260B improve safety and efficiency in air traffic management significantly?

From what I know, the version update from DO-260A and DO-260B offers new features such as on-ground vs airborne source selection logic, ADS-B failure annunciation, the split of the quality indicators ...
Agha's user avatar
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1 answer
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Where is flight following available?

What local facilities are required for me to get flight following services? It seems that if I'm 100 miles from any control tower then I won't be able to get flight following. How close does a ...
SurfandSky's user avatar
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7 votes
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What is the broadcast rate of an ADS-B message?

From what I know, ADS-B (DF=17) message structure is 112 bits long. In terms of type of messages it transmits, there are aircraft identification, surface position, airborne position with baro altitude ...
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