Air/Ground Antarctica

[majoco]

Now that summer is here (the rain is warm!) I'd like to copy the aircraft in and out of McMurdo and Christchurch NZ. However I notice that all the frequencies end in 0.5kHz such as..

K11256.5 US-5 LONG RANGE AIR/GROUND K1 ANTR MCMURDO STATION

...but I have never heard a peep out of any of their frequencies. Does this mean that they have published the frequencies in the old military fashion giving the centre of the USB channel rather than the suppressed carrier frequency?

I see that SWLD gives this frequency as 11256, no decimal.

 

[autovon]

Most of the US transport fleet has modern communications gear like SATCOM, sat telephones and other data links. It is possible that they are using those means instead.

 

[n0nhp]

Yes the military (SPAWAR) does the frequency coordination for the USAP.
The window frequency will be 1.5 KHz below the listed freq so the window will be 11255 on your example.
It has been almost 20 years since I put the transmitters in McMurdo station but at that time there were only 2 5KW and the balance of the base TX were on 1KW transmitters.

I found the disclaimer on the last frequency list I had:


All HF frequencies are assigned frequencies.
To determine the window frequencies, for HF frequencies ending in .5 subtract 1.5,
for frequencies ending in .4 subtract 1.4,
and for frequencies ending in a whole number subtract 2.

Good luck, Hope this helps

Bruce

 

[majoco]

Most of the US transport fleet has modern communications gear like SATCOM, sat telephones and other data links. It is possible that they are using those means instead.

Yes, but you can't talk to ATC directly via Satphone or whatever and it's always helpful to hear other aircraft and know where they are.

Thanks, Bruce, for backing up my thoughts.

 

[autovon]

Is that frequency for ATC or command/control?

 

[majoco]

Well, I got the frequencies from here...

SWLD - Shortwave Listeners Delight - Civilian HF Aviation Frequencies for Antarctica

...and it does mention that "Operated by US Navy & Air Force in NZ and Antarctica" so I guess it's not really "Civil Air". I wouldn't have thought that Satphone would work very well down there, you couldn't have a geostationary satellite that would give coverage below 60South - you might have an "over-the-pole" contact but only every 90 minutes or so for a few minutes only. All the aircraft that come down here must have HF as they fly civil routes in transit - most of the Hercs that used to pass through Christchurch were New York National Guard Reservists crewed - and boy could they drink....

...and a rather old chart I have stored away called the "USAP Band Plan" - haven't got a clue where it came from.

 

[Markb]

According to these logs:

https://www.solarix.net/?s=Mc+murdo

It appears they are using SATCOM, most likely supplemental to HF.

 

[majoco]

Thanks for that, MarkB, I'll plug those frequencies into my R7000 and see what I get.

 

[n0nhp]

They used satcom for comms while transiting to and from NZ. and if HF was poor would use Iridium for on-continent comms. That was when Iridium was much more expensive. I don't know what the policies are at the moment.
The HF is used by both civil and military aircraft in the US/NZ zone for ATC and weather.

The Hercs are still under the command of the New York Air National Guard but pilots from other services and ANG units are fairly regularly rotated through to get LC-130 (Ski equipped C-130) experience (as well as to get the paid trip to the 7th continent).

The Ice XX call signs will be the cargo/passenger flights in wheeled aircraft to and from Christchurch. These will change per the flight.
The LC-130 aircraft will use Skier xx call signs exclusive to the aircraft.


From my recollections, just about anybody headed to or from Antarctica had a handle on putting away copious quantities of antifreeze in Ethyl-alcohol form including the Kiwis.

Bruce

 

[majoco]

They were probably stocking up internally as I guess there's no "anti-freeze" available on McMurdo but there's copious quantities just down the road at Scott Base.....

 

[k7ng]

There was all the anti-freeze for human consumption I ever needed at McMurdo when I was there.

But I had to go over to Scott Base to drink a yard...

 

[VK3RX]

In the past they regularly used SATCOM frequencies in the UHF military range clear voice, either talking to MAC CENTER or DEEP FREEZE OPS in Christchurch.

I scan a couple of SATCOM band plans but I haven't heard them thus far. However last season (late February this year) heard only a couple of times followed by data/digital comms on the same frequency.

They've also used 9032kHz to talk to MAC CENTER but I've not been able to hear anything from here.

More info in various threads in the SATCOM forum under Deep Freeze threads.

 

[majoco]

I don't quite understand what SATCOM is all about. I'm assuming it means "Satellite Communications" but which satellite and where is it? Is it geostationary so I can point a beam at it - 220MHz or so should be quite easy to receive - I have received the LEO NOAA's on just a discone before with satisfactory results.

I have 9032kHz had permanently on for three or four weeks now and I'm getting tired of continual lightning crashes!

 

[N9JCQ]

Martin, this may be a start but its geared towards North America. It may point you in a direction. UHF SATCOM Downlinks Receivable in North America

 

[majoco]

Very good, thanks, it will take me a while to digest all that!

 

[invergordon]

Hi Martin,

Last season I regularly heard the 'Ice' flights from/to CHC on either 8867, 11256, 13261 or 9032kHz, in fact 9032kHz was a good frequency with Mac Centre heard reasonably well. Auckland were heard on the usual MWARA freqs of 8867 and 13261kHz and on 9032 and 11256kHz.

I hope this helps.

 

[majoco]

Thanks for that, Mike. I used to get them loud'n'clear when I lived in Christchurch but I didn't keep a note of the frequencies when I moved up here. That was 20-something years ago when everyone was on HF. I have 9032 and 11256 plugged in to my receiver but nary a peep which is why I was interested in the Satcom. Now that I have some co-ordinates I'll try pointing an antenna at the general direction.

 

[VK3RX]

The U.S. military satellites used UFO-F4 & UFO-F8 are at Longitude 171.8E and 177.8W or thereabouts. While technically in geostationary orbit, the last time I looked at their orbital elements, over the year they did a figure 8 pattern N & S of the Equator. The impression I got was that they moved N & S to support either Arctic and Antarctic activity.

These frequencies right now have continuous data on them, so if you can hear them your antenna is pointed in the right direction for the above satellites (due North from you should suffice, based on the map link below):

258.450
257.050
262.200
258.550
262.100

If you have SDR capability, have a look at the range 251-270MHz and if your system is working, you should see signals all over that range.

https://zaufanatrzeciastrona.pl/wp-content/uploads/2015/07/flsat011.jpg

 

[pastian]

Did you ever run across my Dad Eugene "Gene" Pastian at McMurdo?

 

[majoco]

Thanks Damien, that's very handy. I'm at 175.7561 East so as you say due North True should be close enough. I may have to build a crossed yagi from all the band ll TV antenna bits I have lying around here! If I make the elevation the same as my Sky dish that should be good.....
Thanks for the chart - wish I'd found that a long time ago!