Tower Frequency DOC
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Joined: May 2002
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From: A long way from here.
Tower Frequency DOC
Good evening!
Yesterday at IOM, I overheard (while waiting for some SLF to arrive) an interesting conversation on IOM tower frequency. There was a barely readable (to us) transmission from a Clifton (CLF) callsign, to which the tower responded with:
"Clifton 10, how do you read?"
A further, unreadable transmission from the CLF aircraft. Then, again, TWR responded with:
"Clifton 10, how do you read?"
Nothing this time from the CLF. Then, a BEE aircraft helpfully responded with something along these lines:
"TWR this is BEExxx, CLF10 has acknowldged your transmission, he's trying to contact Kemble tower."
TWR: (rather grumpily) "Yes, I know. I'm just trying to get a point across......he should know what the DOC of a tower frequency is."
OK, so a couple of questions-
What's the DOC of a tower frequency? Does it vary from field to field? And where's it written down? I certainly don't remember it being mentioned in any of my training, but that doesn't mean it wasn't!
Also, is that the kind of thing you ATCers imagine that we know? My captain didn't either...
Cheerio!
CC
Yesterday at IOM, I overheard (while waiting for some SLF to arrive) an interesting conversation on IOM tower frequency. There was a barely readable (to us) transmission from a Clifton (CLF) callsign, to which the tower responded with:
"Clifton 10, how do you read?"
A further, unreadable transmission from the CLF aircraft. Then, again, TWR responded with:
"Clifton 10, how do you read?"
Nothing this time from the CLF. Then, a BEE aircraft helpfully responded with something along these lines:
"TWR this is BEExxx, CLF10 has acknowldged your transmission, he's trying to contact Kemble tower."
TWR: (rather grumpily) "Yes, I know. I'm just trying to get a point across......he should know what the DOC of a tower frequency is."
OK, so a couple of questions-
What's the DOC of a tower frequency? Does it vary from field to field? And where's it written down? I certainly don't remember it being mentioned in any of my training, but that doesn't mean it wasn't!
Also, is that the kind of thing you ATCers imagine that we know? My captain didn't either...
Cheerio!
CC
Joined: Oct 1999
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From: Anywhere
UK AIP GEN 3.4.3.2
2.2
2.2
Use of VHF R/T Channels
(a) Geographical separation between international services using the same or adjacent frequencies is determined so as to ensure as far as possible that aircraft at the limits of height and range to each service do not interfere with one another.
In the case of en-route sectors these limits correspond to that of the ATC sector concerned and those for international aerodrome services are appropriate a radius of 25 nm up to a height of 4000 ft (TWR) or 10000 ft (APP).
(b) Except in emergency, or unless otherwise instructed by the Air Traffic Services, pilots should observe these limits. Services other than international services are provided on frequencies which are shared between numerous ground stations and have to operate to a higher utilisation in order to satisfy the demand for frequencies. Pilots using these frequencies should assist in reducing interference by keeping communications to a minimum and by limiting the use of aircraft transmitters to the minimum height and distance from the aerodrome that are operationally necessary. In the case of TWR, AFIS and A/G facilities, communications on these frequencies should be restricted as far as possible to heights up to 1000 ft in the immediate vicinity of the aerodrome concerned and in any event within 10 nm and 3000 ft.
(b) Except in emergency, or unless otherwise instructed by the Air Traffic Services, pilots should observe these limits. Services other than international services are provided on frequencies which are shared between numerous ground stations and have to operate to a higher utilisation in order to satisfy the demand for frequencies. Pilots using these frequencies should assist in reducing interference by keeping communications to a minimum and by limiting the use of aircraft transmitters to the minimum height and distance from the aerodrome that are operationally necessary. In the case of TWR, AFIS and A/G facilities, communications on these frequencies should be restricted as far as possible to heights up to 1000 ft in the immediate vicinity of the aerodrome concerned and in any event within 10 nm and 3000 ft.
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It's often in the AIP - although, interestingly, neither IOM or Kemble have included it. If ATC people want to make a point it would be a good starting point to publish the info. As far as I know, th only other place that it is specified is on the radio station approval/licence.
Joined: Apr 2000
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From: a galaxy far, far,away...
Used to work at what was then a v busy training field. Tfc along the lines of 4 or 5 in the circuit, 2 or 3 in the stack with another on the procedure & a bunch or arrs and deps. Single freq twr & app procedural , working my bum off & get interrupted by airline c/s calling airport on same or close freq some 150 miles south of us for the wx. He's at f330 or something & blocking my freq for blummin ages.
Didn't happen just once but on many occasions. A phone call to the big airline's chief pilot helped, but crikey! what if I'd had an emergency? Wouldn't have been able to do a thing!
It's not so much the tower DOC but how strong the a/c's tx's are from altitude. HUGE safety implications that pilots need to be aware of.
ap
Didn't happen just once but on many occasions. A phone call to the big airline's chief pilot helped, but crikey! what if I'd had an emergency? Wouldn't have been able to do a thing!
It's not so much the tower DOC but how strong the a/c's tx's are from altitude. HUGE safety implications that pilots need to be aware of.
ap
aceatco, retired
Joined: Sep 2002
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From: one airshow or another
We get serious pee'ed off at Old Warden with CAT calling Connaught/Knock way outside the DOC for the weather and then passing the passenger load, fuel requirement and how many wheelchair lift offs they have!!! Grrrrrrr.
On occasions the CAT tell me to be quiet so they can copy the weather! S'funny, I always have something else to say at that point.
Seriously though, during the actual display we are suppose to have a quiet frequency. We are talking to Gatwick about the problem.
On occasions the CAT tell me to be quiet so they can copy the weather! S'funny, I always have something else to say at that point.
Seriously though, during the actual display we are suppose to have a quiet frequency. We are talking to Gatwick about the problem.
More than just an ATCO
Joined: Jul 1999
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From: Up someone's nose
`VintageATCOBack when we were younger remember Luton and Maastricht both used 120.2 as TWR Freq. Dependant on WX it was often possible to hear traffic in the other circuit +250 n.m. away
Thread Starter
Joined: May 2002
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From: A long way from here.
Interesting stuff, thanks chaps.
I think that the DOC issue is something that various ATCOs (thank-you, Chilli) could make a case for pilots knowing. However, if it ain't made clear to us (eg on an approach plate etc), then it might well be something, in practical ops, that gets missed out.
Have a nice Sunday!
CC
I think that the DOC issue is something that various ATCOs (thank-you, Chilli) could make a case for pilots knowing. However, if it ain't made clear to us (eg on an approach plate etc), then it might well be something, in practical ops, that gets missed out.
Have a nice Sunday!
CC
Joined: Nov 2005
Aviation Qualifications: PPL
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From: Wildest Surrey
DOC's are being added to each airfield's AIP entry; if Jeppesen or AERAD fail to notify them to users then it's not the fault of the individual airfields, it's the fault of the TAP publisher.
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From: Anywhere
Chevvron - teach them the contents of the AIP section I quoted, during the Comms part of the PPL/CPL/ATPL, and airfields wouldn't have to publish them in the first place!
Come on - Which part of "Line of sight" and "Finite number of frequencies" is so difficult to understand?
This should be required knowledge, which shouldn't need to be published on the plates as it's the same everywhere.
Come on - Which part of "Line of sight" and "Finite number of frequencies" is so difficult to understand?
This should be required knowledge, which shouldn't need to be published on the plates as it's the same everywhere.
