123.45

cherokeeflyboy

cherokeeflyboy

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Cherokeeflyboy
I notice that there have been reference's (both here and aopa)to using 123.45 as a freq that folks are using for air to air communication. IIRC my flight instructor told my this is a reserved freq not to be used.
If this is correct what are the ramifications for doing so?
 
cherokeeflyboy said:
I notice that there have been reference's (both here and aopa)to using 123.45 as a freq that folks are using for air to air communication. IIRC my flight instructor told my this is a reserved freq not to be used.
If this is correct what are the ramifications for doing so?
Click to expand...


It is not to be used in the CONUS. But a lot of people do.
 
It's used extensively in NJ. On the shore it's used by banner towing folks heavily, and it's called "Beachball".
 
MSmith said:
It's used extensively in NJ. On the shore it's used by banner towing folks heavily, and it's called "Beachball".
Click to expand...
You'll hear people say they're going to "finger", meaning 123.45.
 
It is reserved.
No one can ever seem to remember the two proper frequencies so that is what gets used. Maybe in deference to the constant use, the FCC would allow a switch?
 
FCC Rules, Part 87.303(a) reserves 123.45 for flight test operations with the following restriction: Mobile station operations on these frequencies are limited to an area within 320 km (200 mi) of an associated flight test land station.

Unless the banner tow operations are flight test (which I highly doubt), they are in violation of the FCC rules when using the frequency.

I do agree, however, that the (mis)use of 123.45 is wide spread.

Interestingly enough, while I remember 122.75 and 122.85 being called out for fixed wing air to air communications when I was a student pilot, FCC Rules Part 87.187(j) only calls out 122.75 for fixed wing (and 123.025 for helicopters) air to air communications. 122.85 is now called out for multicom or aviation support functions. Don't know when this was changed, but the latest revision to 87,187 occured on June 14, 2004.

It's true, a pilot is always learning...
 
Thanks Ghery,
Thats the info (ammo) I was looking for....wonder what the penalties
are for using the wrong freq's??
 
Let'sgoflying! said:
It is reserved.
No one can ever seem to remember the two proper frequencies so that is what gets used. Maybe in deference to the constant use, the FCC would allow a switch?
Click to expand...

Fat chance although it kinda makes sense ala 555-1212 for directory assistance. WRT the original question, 123.45 is assigned by the FAA for flight testing by aircraft manufacturers. And it is "illegally" used by many pilots all over the country. I suspect that the legitimate users of 123.45 get quite ticked off about the casual use of this frequency simply because it's easy to remember. The frequencies assigned for air to air (airplanes) are 122.85 and 122.75.
 
cherokeeflyboy said:
Thanks Ghery,
Thats the info (ammo) I was looking for....wonder what the penalties
are for using the wrong freq's??
Click to expand...

The FAA does have the authority to levy some pretty heavy fines, but AFaIK the most likely "penalty" is the ire of a legitimate user. Then again if you managed to obstruct a flight test costing hundreds of thousands of bucks, you might get sued for that.
 
Can't remember specifically, but isn't 123.45 the air to air frequency in Canada?
 
As noted elsewhere, 123.45 is designated for interplane comm in the Oceanic areas, but is reserved for flight test ops by Boeing, Lockheed, etc., in the Continental US. Don't be jamming up their operations -- that could get someone hurt on a test flight. 122.75 and 122.85 are the only general use interplane freqs authorized in the CONUS (plus 123.025 for helos). See AIM 4-1-11 for details.
 
Ron Levy said:
As noted elsewhere, 123.45 is designated for interplane comm in the Oceanic areas, but is reserved for flight test ops by Boeing, Lockheed, etc., in the Continental US. Don't be jamming up their operations -- that could get someone hurt on a test flight. 122.75 and 122.85 are the only general use interplane freqs authorized in the CONUS (plus 123.025 for helos). See AIM 4-1-11 for details.
Click to expand...

Ron, check my comments above. The FCC Rules only call out 122.75 for air-to-air these days. They give 122.85 to other purposes. It changed somewhere in the past few years. If the AIM is still saying 122.85 is available for air-to-air, it needs updating.
 
Interesting, I wonder when it changed. I also found this:

(bb) The frequencies 121.950 MHz, 122.850 MHz and 127.050 \1\ MHz
are authorized for air-to-air use for aircraft up to and including 3 km
(10,000 ft) mean sea level in the vicinity of Grand Canyon National Park
in Arizona within the area bounded by the following coordinates (all
coordinates are referenced to North American Datum 1983 (NAD83)):
---------------------------------------------------------------------------

\1\ Until further notice this frequency is available for air-to-air
use as described in the Grand Canyon vicinity. Availability is a result
of the FAA's assignment of this frequency. If the FAA reassigns this
frequency the Commission may require air-to-air use to cease.

36-27-59.9 N. Lat; 112-47-2.7 W. Long.
36-27-59.9 N. Lat; 112-48-2.7 W. Long.
35-50-00.0 N. Lat; 112-48-2.7 W. Long.
35-43-00.0 N. Lat; 112-47-2.7 W. Long.
 
I don't think its going to hurt anyone, but I'd shoot for using another frequency if possible. No one is going to know its you unless you start using your tail numbers, desinations and full names. :) If I heard anyone on there, I'd probably go find another freq to use.

Plus, unless you're up high, that VHF signal isn't going too far. Wait, I take that back... Half the country doesn't have 'mountains' to block the signal... :)
 
Ghery said:
Ron, check my comments above. The FCC Rules only call out 122.75 for air-to-air these days. They give 122.85 to other purposes. It changed somewhere in the past few years. If the AIM is still saying 122.85 is available for air-to-air, it needs updating.
Click to expand...
The latest change to the AIM (Change 3, effective 8/4/05) still shows 122.85 as an air-to-air frequency in Table 4-1-3, although I see the information you posted on the official CFR web site with a latest revision date of June 14, 2004.

http://a257.g.akamaitech.net/7/257/2422/12feb20041500/edocket.access.gpo.gov/cfr_2004/octqtr/47cfr87.187.htm

Guess someone ought to get the FAA and FCC talking to each other -- and not on 122.85.
 
AirBaker said:
Plus, unless you're up high, that VHF signal isn't going too far. Wait, I take that back... Half the country doesn't have 'mountains' to block the signal... :)
Click to expand...

This is a pilot forum and not a ham radio forum so I won't go too technical into the radio stuff. But since I am a ham I have to chime in with a comment to dispute that. The ham radio VHF band is at 144MHz (20MHz higher than the airband) in that band and with reasonable power, from the Midwest I have spoken to 20 countries on VHF.

I have antennas optimized for it and the propagation was excellent but it is still possible for VHF line-of-site signal to travel vast distances. From an airplane up high they could go quit far. One of the propagation modes that can really cause the signals to go far is when the aurora borealis is active. Another is when there are thunderstorms around that will cause the signal to duct through the atmosphere, plus some other atmosprehic conditions.

Scott
K9PO
 
smigaldi said:
This is a pilot forum and not a ham radio forum so I won't go too technical into the radio stuff. But since I am a ham I have to chime in with a comment to dispute that. The ham radio VHF band is at 144MHz (20MHz higher than the airband) in that band and with reasonable power, from the Midwest I have spoken to 20 countries on VHF.

I have antennas optimized for it and the propagation was excellent but it is still possible for VHF line-of-site signal to travel vast distances. From an airplane up high they could go quit far. One of the propagation modes that can really cause the signals to go far is when the aurora borealis is active. Another is when there are thunderstorms around that will cause the signal to duct through the atmosphere, plus some other atmosprehic conditions.

Scott
K9PO
Click to expand...

Just curious, about how much do you have invested in your system ? It sounds quite capable.
 
Dave Krall CFII said:
Just curious, about how much do you have invested in your system ? It sounds quite capable.
Click to expand...

Probably about $4000, my radio station grows ans shrinks depending on what I want to be doing with it. Sometime I like to expiriment with new modes. It is starting on a down cycle and I will be selling stuff.

The big expenditures are the radio, antennas, and transmission line (coax). I don't have any huge power amps and at those frequencies I can only run 50 watts. But I do have big gain type beam antennas, so I can put the power where I need to. The big thing I have been doing lately is bouncing signals off of the trails of meteors. Managed to contact a guy in California using only 5 watts of power at 50MHz.

amail me if you wnat mor einfo, I don't wish to completely hijack the thread.

Scott
 
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AirBaker said:
Plus, unless you're up high, that VHF signal isn't going too far. Wait, I take that back... Half the country doesn't have 'mountains' to block the signal... :)
Click to expand...

Wednedsay, I heard the airborne half of a conversation between a pilot on an American Eagle flight and his Dad on the ground. The pilot was as FL370 and was over south Florida. I was at 2500' over middle Georgia. I could hear the pilot as clearly as if he'd have been in the pattern with me.:)
 
smigaldi said:
This is a pilot forum and not a ham radio forum so I won't go too technical into the radio stuff. But since I am a ham I have to chime in with a comment to dispute that. The ham radio VHF band is at 144MHz (20MHz higher than the airband) in that band and with reasonable power, from the Midwest I have spoken to 20 countries on VHF.

I have antennas optimized for it and the propagation was excellent but it is still possible for VHF line-of-site signal to travel vast distances. From an airplane up high they could go quit far. One of the propagation modes that can really cause the signals to go far is when the aurora borealis is active. Another is when there are thunderstorms around that will cause the signal to duct through the atmosphere, plus some other atmosprehic conditions.

Scott
K9PO
Click to expand...
Hi Scott i too am a ham operator N3XBN, and i see we both fly the same kind of plane too 1980 PA28-161 Dave G
 
Shipoke said:
Hi Scott i too am a ham operator N3XBN, and i see we both fly the same kind of plane too 1980 PA28-161 Dave G
Click to expand...

There seems to be a fairly high percentage of ham/pilots. Do you operate any ham equipment form your plane?
 
smigaldi said:
This is a pilot forum and not a ham radio forum so I won't go too technical into the radio stuff. But since I am a ham I have to chime in with a comment to dispute that. The ham radio VHF band is at 144MHz (20MHz higher than the airband) in that band and with reasonable power, from the Midwest I have spoken to 20 countries on VHF.

I have antennas optimized for it and the propagation was excellent but it is still possible for VHF line-of-site signal to travel vast distances. From an airplane up high they could go quit far. One of the propagation modes that can really cause the signals to go far is when the aurora borealis is active. Another is when there are thunderstorms around that will cause the signal to duct through the atmosphere, plus some other atmosprehic conditions.

Scott
K9PO
Click to expand...

Well, I too know the 'possibilities' of VHF travelling farther. AMSAT, Moonbounce, tropospheric ducting, etc.... Its just not that realistic. :)

We have 10? watts from a little vertical antenna? No amplifiers and multi element beam antennas. :)

My point being that the size of the disturbed area by your transmission would be relatively small.

Keith Lane said:
Wednedsay, I heard the airborne half of a conversation between a pilot on an American Eagle flight and his Dad on the ground. The pilot was as FL370 and was over south Florida. I was at 2500' over middle Georgia. I could hear the pilot as clearly as if he'd have been in the pattern with me.:)
Click to expand...

You can see a long ways from up there.. Like I said earlier, you don't have the Sierra Nevada mountains in your way either! ;)



Chris
KC6PPD
 
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