On The Airbands

The controller transmitted . . . “Buckshot triple-one, request your angle of bank and maximum ‘g’ forces. ” Buckshot 111 replied with . . . “85 degrees AOB, and we are pulling a max of 4. 5g’s. ”

A split second later, a crew member of the 727 queried the Tower controller with . . . “what airline’s that?” Quick Tower reply: “Bob Hawke’s!”

That little piece was submitted by Terry McMahon from Tugun in Queensland, and was his maiden offering to these pages. Hope it won’t be your last contribution Terry! * * * Some frequencies from central Queensland for some company operations you may be interested in monitoring are supplied courtesy of young Karl Jaques, a regular “airbander”. CHAT (Central Highlands Air Taxis) 126. 4; Utah Mining/Mt Isa Mines (bizjets) 126. 4; Lloyds/Piccolo 126. 4; Sunstate 130. 25; Australian 129. 5; Ansett 130. 6. While using his Yaesu FRG-8800 to monitor 17904kHz for the South Pacific area, Karl recently heard Honolulu discussing “gas levels in the cabin” of an aircraft somewhere in the Honolulu FIR. Karl was studying while listening, and after hearing that downed the books and turned up the speaker volume.

There had actually been a plane crash on or near to Yap, which is located in the Caroline Islands in Micronesia. The time was approximately 0300 zulu when a Navy aircraft, callsign “Navy 837” came up of the frequency stating . . . “I can see personal effects on the surface of the water!” The unfortunate aviators were the crew from a light aeroplane being delivered to Singapore. The aircraft apparently went down in the water very close to land, immediately following takeoff. At least one passenger survived the impact and was treated at the scene by an attending physician. Karl didn’t actually hear anything about the fate of the pilot, as Honolulu cut sort a Sitrep by the crew of Navy 837, a message which was certain to contain those details. Considering Karl only intended to hit the books that day, the afternoon was certainly spent very differently to the way Karl expected to spend it. You just never know what will happen while monitoring the aviation bands! These situations do happen, and if you are monitoring the frequency in use at the time, you will hear what’s going on. * * * During the recent Gulf War, Lawrence Harris, a lecturer at Plymouth University in the United Kingdom, totally amazed the British Ministry of Defence by ingeniously monitoring communications carried out through transponders of the European

Space Agency’s Meteosat-4 satellite. He was in fact monitoring he Allied military buildup, in addition to keeping an ear on weather conditions in the Gulf day-to-day. Lawrence commented that if he could do it so easily, then so could the Iraqis, and they most likely were doing just that! The British Ministry of Defence even considered having the satellite link shut down when they heard about “Hacker Harris” and his activities. The simple beauty of this story is the equipment Lawrence used: one homemade chicken-wire satellite dish, and bargain priced satellite receiver and low-noise amplifier! * * * During my visit to the US last year I met an extremely interesting and very keen airband monitor named Ed Flynn, from San Rafael near San Francisco. Ed is heavily into monitoring AGARS downloads from overflying aircraft on frequencies 131. 55 and 130. 025. The latter frequency has only been in use for a relatively short time. Australian aircraft flying domestic or international routes are at present downloading on 131. 55 using 2,400 baud commercial packet. At one stage, I believed the speed to be 9,600 baud, but it is in fact the slower of the two. Ed Flynn monitors the Aeronautical Communications Addressing and Reporting System after learning about its intricacies from an American FAA employee. The FAA man, Bill Tobin, eventually sent Ed a computer program for his Tandy Model 4 computer. Under Bill Tobin’s direction, Ed built up a small “black box” interface unit to tie his radio into the computer, with encouraging results at first. Ed admits he is no computer expert or electronics technician, and at the present time states that he is experiencing a few problems. In fact, ninety percent of what he is monitoring on AGARS is coming out “garbage”. The aircraft are receiving only messages addressed to the “tail number”, and the ground only hears messages addressed to the relevant company. Ed’s monitoring station receives everything on the frequency . . . and he thinks this may constitute part of the problem, although he hasn’t gone into more detail on what his suspicions are. He has another problem . . . being line-of-sight properties of the VHF radio wave. Living at San Rafael, which is 30kms to the north of San Francisco, he seems to be missing a great many ground station replies, or when he does receive the ground station, the text is highly corrupted. Not all airlines in continental USA use AGARS, but its usage is growing with the addition of new two crew arrangements, and increasingly computerised flightdecks. American, United, Delta, USAir and TWA are currently the biggest users of the system.

They tried it out on the HF bands but gave it away due to text corruptions caused by band interference.

The way it is, any aircraft at 27,000ft or above within Continental USA is in range of an AGARS station, so the Americans have complete nationwide VHF AGARS coverage.

Ed Flynn has put in a lot of great work on AGARS decoding, and recently supplied me with copious printouts of his results. Notwithstanding his problem areas, the transmissions he can decode are all-revealing, from entire flight plans, alternate terminal information, fuel figures, “tail” numbers, serial codes, passenger problems and illnesses, cabin staffing requirements and amendments. You name it . . . it’s there! And if you ask me, Aussie monitors are going to have to address the need to install AGARS decoding equipment if we wish to fully enjoy our aircraft monitoring hobby in the future.

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From Hayden Brown, who lives on the other side of the Pacific “pond” from Ed Flynn, in Timaru, New Zealand, we have this story.

AIR NEW ZEALAND 131: ”Auckland, Auckland, New Zealand 131 on 5643, pre-flight check, bound for Brisbane. ”

AUCKLAND OCEANIC: “New Zealand 131 this is Auckland, I read you fives, primary 5643, with secondary 8867, go ahead your selcal code. NEW ZEALAND 131: ”Ahh . . . heh . . . Auckland, you’ll have to bear with us here, ah . . . standby, the . . . ah . . . registration plate has just fallen off the dash panel, and we know not where it is!”

Pause . . .

NEW ZEALAND 131: “Well . . . err, alright . . . we found it now Auckland . . . heh . . . it’s Echo Papa Juliett Lima the selcal!” AUCKLAND OCEANIC: ”A little bit like losing your wallet!”

Hayden monitors the HF bands using a new Philips D2999 phase-locked loop (PLL) receiver with digital tuning, and sixteen memories. The receiver is hooked up to a 30m copper wire, strung between house and water tank. All Hayden’s VHF monitoring is handled using a WIN-108 handheld, from Global Aviation Support, which he saw advertised in this magazine near our feature. He says he is delighted with the radio’s performance. Thanks for the letter Hayden, and the appraisal of the WIN-108.

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Peter Leigh from LloydHelicopter Group based at Latrobe Valley Airport writes to say he was returning to Latrobe Valley from an ambulance tasking one Christmas Eve in Bell 412 tail number VH-UAH. They were transferred from Melbourne Control to Melbourne Flight Service.

Peter Leigh’s fun-loving co-pilot Murray Colvin called up the FIS station: “Melbourne, this ishelicopter Uniform AlphaHo-HoTel, maintaining five thousand five hundred. ”

Flight Service replied in a super deadpan voice: “Uniform Alpha Ho-Ho-Tel, area QNH is one-Ho, one-Ho!”

Appreciate the letter Peter, . . . (and Murray!)

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Some more callsigns to add to your military list, the first three courtesy of Jorge Washington from Fleet Support at Naval Air Station Nowra.

Spider – Learjet 35a involved in RAAF target towling duty; Cobweb- same aircraft type, same duty; Baldock – Learjet 35a involved in Naval target towing.

Greg Wilson from Western Australia can’t help me with the one I’m chasing from the USAF that came into Richmond just once, from the USAF, callsign “MOJO”. But he reveals the following USAF calls monitored recently to our north.

Astra- B-52s from Diego Garcia to Guam; Thor – same aircraft, same routes; Hoser- KC-135 tankers operating from Clark AFB in the Philippines; Stuk- KC-10 tankers; Medevac – DC-9 Nightingales;

And from the RAAF, “Destroyer Black”, used for the first time recently by Blackhawk crews on exercise in WA with the SAS.

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A reader who supplied all details of his name and address but doesn’t want them published supplies the following story. Our correspondent comes from South Australia.

The exchange occurred a few years ago in the oilfield country of far western Queensland where there was the usual banter between the “real men” (chopper pilots) and the “wimps” (flying fixed wings).

A Cessna 402 was having problems with the wheels not showing down prior to making an approach. There was lots of radio communication traffic from everyone aloft.

NORM (chopper pilot): (trying to behelpful) “Err, I’m twenty minutes away, and I can fly near you and look. ”

CESSNA PILOT: (very agitated) “Look man. . . . tm not waiting twenty minutes for you to inspect my plane!”

NORM (chopper pilot): “I don’t want to inspect your plane, I just wanta watch you land it!”

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Apparently I very much upset some CAA people with a small editorial last December. I will be presenting their replies next issue, hopefully. So look forward to that. Contributions please to Bob Bell, PO Box 301, ChesterHill, NSW,