Questions tagged [radio]

Radio equipment, including antennas, receivers, two-way radio systems, and more.

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Why is the quality of radio communication bad?

Why don't modern planes and ATC centers have good-quality audio for communication? For example in this video: Or basically any other example of pilot communication(...
ScienceSamovar's user avatar
23 votes
5 answers
9k views

Does ATC hear the same poor audio I hear on LiveATC?

When listening to air traffic control (ATC) communications on something like LiveATC there is a lot of feedback/static that often makes it difficult to hear. Do controllers hear the same feedback and ...
user avatar
19 votes
3 answers
5k views

Do pilots ever talk directly to each other over radio?

Do pilots ever talk directly to other pilots over air band radio, or only to air traffic control?
Someone's user avatar
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17 votes
1 answer
14k views

What is the night effect?

I read the night effect takes place in radio navigation, especially VOR and NDB. My questions are: What is its nature? Why does it occur? What are the consequences of it?
wiaim's user avatar
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15 votes
2 answers
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Do transoceanic airliners monitor marine VHF emergency frequencies?

I know that modern jetliners often have a multitude of radio equipment on board, including VHF, HF, satellite, etc. From what I've read (such as here), it's customary for jetliners to monitor 121.5 ...
heypete's user avatar
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15 votes
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What radio frequency bands are associated with the long wire antennas, why do some aircraft have them and others don't?

On many older aircraft, and in vintage aircraft photos, you can often see long wire antennas strung from some point on the top of the fuselage to the top front of the vertical fin. On newer aircraft, ...
Anthony X's user avatar
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15 votes
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Can I fly with an airband receiver in the United States?

I'm flying with American Airlines on a cross-country flight soon and was thinking about bringing along my airband receiver/scanner since it'd be fun to listen to ATC. It looks like I'd be unable to ...
Jeff B's user avatar
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15 votes
3 answers
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Why shouldn't you use HF radio while refueling?

FCOM limitations for many aircraft state: DO NOT USE HF RADIO WHILE REFUELING Why is this? I have heard from people that it's because most of the big airliners have a 'notch' antenna for HF; it's ...
Praveen Pillai's user avatar
14 votes
2 answers
13k views

OBI, RMI, HSI... What combination do GA aircraft w/o glass typically have?

I'm learning about radionavigation, and all the various analog displays that can be used: Automatic Direction Finder (ADF) - Provides basic bearing information to practically any radio source the ...
KeithS's user avatar
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11 votes
4 answers
10k views

Can normal PC headsets replace 'aviation' headsets?

Aviation headsets have noise reduction and a larger jack (1/4") than most PC headset counterparts (1/8"). But there are many excellent quality PC headsets with sound-proofing materials which ...
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11 votes
4 answers
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How would ATC try to establish contact with a VFR craft?

Example: I'm in a 172 tailed N1234A, on a pleasure hop between Hicks Field and Addison, circling around DFW International to the north, flying at 1500ft within DFW's Mode C veil under VFR (so I'm ...
KeithS's user avatar
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10 votes
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How does the emergency frequency work?

When I'm flying from my airfield, I usually am out of range of the airfield's radio within 50 miles or so, at low altitudes. How does the emergency frequency (121.50) work? Where is the location of ...
Cloud's user avatar
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10 votes
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Why don't transponders have active and stand-by value like radios?

This answer explains how pilots when switching code on transponder should either carefully avoid temporarily squawking one of the emergency codes, or should temporarily put the transponder in stand-by....
Jan Hudec's user avatar
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How to record Intercom / ATC in a small aircraft like a Piper Archer?

For making videos it would be nice to have some more sound than the engine sound recorded by my GoPro. What ideas do you have to record the aircraft intercom? It won't be a problem for me to have two ...
Falk's user avatar
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Why do some airport towers avoid monitoring 121.5?

In the USA airport facilities directory (AFD), some towers (eg KSJC) are listed with the note: Emerg frequency 121.5 not avbl at tower. Why do these facilities not monitor guard? Does the note ...
Peter's user avatar
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9 votes
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5k views

Can VOR indication be reliable if one of its antennas breaks?

What will be the reliability of the VOR indication inside the cockpit if one of the two outside antenna is broken ? Can we trust it to make a VOR approach? What will be the consequences assuming ...
Thomas's user avatar
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1 answer
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What's the meaning of underlined frequency in sectional chart nav aid box?

There is a statement to describe the underlined frequency in legend, it says: Underline indicates no voice on this frequency. What does this mean? We still need to ident the Morse code, doesn't it?...
JuanLoveJesus's user avatar
9 votes
2 answers
2k views

How can I find the location and coverage of aviation VHF transmitters?

In the USA, is there a way to find locations of VHF transmitters that are used for air traffic communication, and the frequencies they transmit/receive on? There are some places (Northern Bay Area, CA)...
CJBS's user avatar
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8 votes
6 answers
3k views

Is there a solution to radio interference?

I was reading about the Tenerife Disaster and came across what seemed to be the probable cause behind the accident. A simultaneous radio call from the Pan Am crew caused mutual interference on the ...
Prodnegel's user avatar
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8 votes
3 answers
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What radios are airliners / large aircraft equipped with?

I know that pilots have to talk to the tower over the radio, and apparently you have to tune the radio to the right tower frequency. I've also heard that in an emergency, you're supposed to "squawk ...
raptortech97's user avatar
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Is it legal to use a home-made Airband radio receiver in the United States?

I work at a local small airport (very small, if we get more than about 10 or 15 airplanes taking off/landing it's a "busy day") and I mow the runways (we have multiple grass ones). Because of the ...
RPiAwesomeness's user avatar
8 votes
2 answers
1k views

What licenses do I need to transmit on AirBand frequencies?

I am not a pilot, but at my company we are trying to figure out what FCC licenses we need to use to talk to our pilot when we are on the ground and they are flying. My research has led me to mixed ...
Max's user avatar
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8 votes
2 answers
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What is transmitting this radio signal @~110.515MHz and for what purpose?

I was scanning the local aviation radio frequencies, and came across an odd signal (listen to a recording here). It's at around 110.515MHz, and it seems strong within a 30 mile radius of Shropshire, ...
sircompo's user avatar
  • 121
8 votes
2 answers
2k views

Which FCC license do I need to operate an aviation radio on the ground?

I'm in the process of buying a handheld radio as a backup for when I go flying. According to the owner's manual, I'd need a ground station license to operate it when I'm not actually in an airplane, ...
HiddenWindshield's user avatar
7 votes
3 answers
2k views

Why is radio communication still used?

Why is radio still the method of communication from the ground to air? If i'm not mistaken, cellular services should be much better in quality and reliability
Nicholas Smith's user avatar
7 votes
2 answers
2k views

How unusual were MH370's final ATC exchanges?

There are 2 noteworthy occurrences in the ATC radio transcript within just minutes of a 3rd noteworthy, quite unprecedented occurrence in aviation history: At 01:07:55 MH370 unnecessarily reported ...
summerrain's user avatar
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7 votes
3 answers
11k views

How many antennae are there on a typical small aircraft, and how are they connected to the avionics?

As far as i know there are a bunch of antennas on board of a small (EASA CS-23) plane: GPS is for GPS navigation in MHz VHFVOR is for NAV and Glideslope/Localizer ADF is for ADF DME is for DME ...
MightyMirko's user avatar
7 votes
1 answer
627 views

Question about congestion of the 1090MHz frequency

I'm no expert so there's likely to be a lot of mistakes in this post. ADS-B - Automatic Dependent Surveillance - Broadcast, (out) transmits (in) receives position data from/to other aircraft and to ...
Rory McDonald's user avatar
7 votes
1 answer
554 views

Which radar altimeters are susceptible to 5G C-band altimeter interference?

There is apparently a great deal of consternation over the pending expansion of 5G The emergency petition claimed that interference from the C-Band "will cause irreparable harm and jeopardize ...
Machavity's user avatar
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6 votes
2 answers
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What requirements are there for radio systems in aircraft?

What are the requirements for radio systems in aircraft? For example, are there requirements about: Reception ability Transmit ability Transmit power This is primarily about voice communication ...
fooot's user avatar
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6 votes
2 answers
1k views

Do left and right mic buttons control both headset microphones?

The aircraft I was flying today has a push to talk integrated button on each control yoke. I was sitting in the right seat, but my headset was plugged into the jacks on the left side of the cockpit. ...
Lee's user avatar
  • 61
6 votes
4 answers
3k views

How do pilot and copilot operate and coordinate the radio?

How do the pilot and copilot of a large commercial jet operate the radio when talking to ATC? Is there a push-to-talk button, or some voice-triggered mechanism? Also, how do they coordinate it? How ...
DrZ214's user avatar
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6 votes
2 answers
943 views

What will be in 'radiotelephony privileges' part of EASA PPL without practical RT examination?

My question is addressed to pilots who recently obtained PPL in Europe (preferably in Czech Republic, but not so important). As I understand, EASA itself does not require separate radiotelephony ...
avtomaton's user avatar
  • 532
6 votes
1 answer
2k views

Is there anything better than LiveATC to get accustomed with RT phraseology?

I would like to "train my ear" for RT communications and I tried to listen to approach of Dublin's Airport. I simply can't understand more than 50% words because of loud background whistle and poor (...
super jet 100's user avatar
5 votes
3 answers
2k views

Exactly what kind of radios are prohibited for passengers inside an aircraft?

I know that passengers are asked to put their cell phones on flight mode. But some carriers allow use of WLAN on-board. So, what radios should passengers refrain from using? Also, if a person uses a ...
pri's user avatar
  • 155
5 votes
2 answers
9k views

How to check if (small) aircraft's radio is working properly?

Is there a standard way to test/check aircraft's radio without calling anybody (Ground/Tower) to see if it is receiving and transmitting? Is there a way to check aircraft radio with your own ...
pmoubed's user avatar
  • 2,025
5 votes
2 answers
2k views

What was the range of a low-frequency radio range station?

The low-frequency radio range is a historic navigation aid that was in use from the 20's to the 70's. I find it quite interesting. Using AM frequencies, what was the range of a high power LFR station?...
user avatar
5 votes
2 answers
10k views

How does the PTT button on the radio work?

I've always seen a button either built into the yoke or attached to the yoke with velcro on older aircraft. However, the other day my instructor used an older-looking headset that had a push to talk ...
Pugz's user avatar
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5 votes
2 answers
523 views

How to avoid talking over others when using different send/receive frequencies?

Related to this question about flight services: when I talk to FSS over the generic or the local receive-only frequency while listening to the VOR voice channel, how do I avoid talking over others on ...
Simon Richter's user avatar
5 votes
1 answer
2k views

Does radar altimeter work over the ocean?

I'm wondering if radio waves are reflected by the sea. If so then the usual radar altimeter would work. If not, then is there any other fallback besides barometric altimeter? According to the wiki ...
DrZ214's user avatar
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5 votes
1 answer
559 views

What does a DME indicator do in HOLD or RNAV mode?

I found this DME indicator on the Cessna 210. Its mode switch has four positions - NAV1, NAV2, RNAV and HOLD. NAV1 and 2 are clear - it uses the NAV1 and 2 freq respectively. I'm wondering what the ...
TheEagle's user avatar
  • 1,394
5 votes
1 answer
791 views

What are the ways to perform air traffic control on long distance flights? [closed]

I have a few questions on air traffic control. From my understanding, there are three major ways of sending control messages to an aircraft: 1) Direct radio link from control as long as the aircraft ...
Teodorism's user avatar
  • 455
5 votes
1 answer
1k views

What do the radiation patterns of ADS-B transmissions on large airliners tend to look like?

In the recent article Flightradar24 gears up for a new wave of flight tracking I've read about FR24's experimental Wave Glider ADS-B receiver - essentially a self-propelled, solar power buoy as a ...
uhoh's user avatar
  • 5,808
5 votes
2 answers
2k views

As a passenger, can I use my handheld radio in commercial flights?

During flight from one country to another, can I use my hand held radio during flight to listen to ATC?
pmoubed's user avatar
  • 2,025
5 votes
1 answer
400 views

Did the Westland Lysander have a helmet/face mask for radio communication during WW2?

I have a character in some war-time fiction I'm writing 'acquiring' an aircraft (a Westland Lysander). Just need to know: was there a helmet/face mask for radio communication for these aircraft? And,...
Grateful_Jim's user avatar
4 votes
2 answers
2k views

Is there an ATC radio backup?

I was thinking, what would happen if the radio systems for an ATC tower fail due to power loss or faulty systems? Is there any kind of backup radio that would be used to contact the planes and/or ...
Mark's user avatar
  • 49
4 votes
2 answers
2k views

What can cause my radio to transmit nothing but a terrible noise?

I have replaced the noise filter and checked the jacks. It does not matter what headset or jacks are used. I replaced the audio panel and had the radio serviced. When I transmit all I hear is a low ...
Jeff Leard's user avatar
4 votes
2 answers
3k views

How strong would a servo motor need to be to power the control surfaces of a fixed wing ultralight aircraft?

I'm looking to build an ultralight aircraft. The video above shows a good example of how one is controlled with wires or with metal fulcrums/levers, but I am ...
TrapAlcubierreDrive's user avatar
4 votes
1 answer
232 views

Just how inaccurate are (Las Vegas) VOR radials?

I was discussing VOR-based navigation with a pilot, and he mentioned that VOR doesn't provide a very high level of integrity and safety (at least, compared to GPS or DME). He explained that the FAA ...
Cody P's user avatar
  • 6,783
4 votes
1 answer
578 views

Can aviation HF radios receive while transmitting?

I was listening to Gander Radio on HF at 5616 kHz today and I've noticed that operator at Gander would often start transmitting reply before the airplane finished transmission, as if trying to ...
AndrejaKo's user avatar
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