Airspace Management

GROUND: “Oh… about ten thousand kilometres I’d imagine!”

It’s short, but sweet. Thank you Phil for the story, and keep them coming in. Now that we all know how fast the guys and girls in Melbourne Tower/Ground staff are with quips, here’s an article actually sent in to me by the staff at Melbourne Tower! And, surprise surprise … it has to do with the tractor-tug crews!

I’ll let the Tower staff take up the story:

“The tugs operating at Melbourne Airport have various ways of moving aircraft around the area. Some aircraft are towed forward, some are pushed backwards for considerable distances, whilst others are pushed forward with the tug positioned behind the nose undercarriage.

Recently we in Melbourne Tower asked a tug driver pushing a British Airways 747 from one side of the International terminal to the other why he was doing an underbelly push.

TOWER: “Yellow 2, why do you do an underbelly push?”

YELLOW 2: “Ahh … we find it easier in some of these older tugs (short pause …) Some prefer to do it underneath, and some like to push from behind, and some like to pull from the front!”

UNIDENTIFIED: (not confirmed, but the suspect is a 767) “It depends on her!”

I’m grateful to the always friendly staff at Melbourne Tower. Hope to hear from you again soon.

Mark Kavanagh lives near Kempsey Airport, on the mid north coast of New South Wales. He became interested in monitoring the local CTAF and area frequency about the time he started flying training for his PPL (Private Pilot’s Licence).

During the past year, Mark has monitored and observed some spectacular sights in relation to nonstandard aircraft seen in the Kempsey CTAF, the first being an F-111, (using an 82 Wing callsign) “RAMROD”. Mark monitored this aircraft on area frequency 122.6 MHz, providing all its details to Sydney FlightWatch, and was surprised when he heard it at 15nm (28km) south of Kempsey, at 500 feet AGL. He quickly went outside, radio in hand, to get a visual sighting, and heard it call inbound on the Kempsey CTAF 126.7 MHz:

“Traffic in the Kempsey CTAF, Ramrod 14, an F-111, ten miles to the southwest of the field, inbound at 500 feet, tracking runway heading for a low level pass”.

When Mark heard this, there was no other traffic, and he saw the very best sight imaginable. One very sleek F-111 roaring past his house down Runway 04, then climb and bank hard right, to follow the coast to the Evans Head range. An event not to be forgotten.

The next incident was a Qantas 767 calling inbound to the Kempsey CTAF! On board were a number of terminally ill kids, the flight sponsored by the Ronald McDonald House on a sightseeing sortie over the town:

“All traffic Kempsey CTAF, Qantas 767 Oscar Golf India is orbiting overhead the township at 3000 feet for the next two minutes, then we’re tracking coastal to the north for Brisbane.”

Again, there was no other traffic in the CTAF area at the time this occurred.

Mark Cavanagh says that the only other large aircraft he has actually seen touch down at Kempsey (which is a small country airstrip) was an RAAF C-130 Hercules on a training mission! Mark has ordered “Climb into the Cockpit by Radio” from us, which is the most detailed aviation radio monitoring book anywhere in the world, and the only one produced in the southern hemisphere! It’s $22.95 including post from Airband Communications, PO Box 16, Georges Hall 2198. Bankcard, Mastercard and Visa accepted.

We don’t seem to devote much space to space! Who monitored the Space Shuttle and MIR during the historic docking mission by Atlantis? It was the first docking of American and Russian spacecraft in 20 years, and was very complex, requiring a great many communications circuits to make it happen.

Shuttle Commander Robert Gibson said after returning from the 10 day mission that “two such massive objects have never docked before in space”. After the successful docking and stay with the Russians, Atlantis conveyed Cosmonauts Vladimir Dezhurov and Gennady Strekalov, along with NASA Astronaut Norman Thagard, back to earth. The Cosmonauts had been in space on board MIR for more than three months, and Thagard had been the first American to fly on a Russian space station. Yes, there were lots of “firsts” on this mission.

Here are some communications facts and frequencies you will want to know about. Primary downlink communications from the Shuttle to Houston Mission Control take place on S-band microwave 2287.5 MHz, which are digital, wideband, multiplexed transmissions. Another S-band channel, 2250.0, is used to relay engine telemetry data and TV signals from the Shuttle back to earth. Both of these S-band frequencies work through the use of two special orbiting communications satellites, known as TDRS, or “Tracking Data Relay Satellites”, located above 41 degrees West and 171 degrees West, deep in space. There are a few more downlinks, on 2217.5 MHz, 2214.0, and 2205.0 MHz. Uplinks are on 2106.4, 2041.9, 1831.8, and 1775.9 MHz.

The Shuttle is also on numerous Ku-band channels near to 15.003 GHz, using high speed digital data links. But forget all these. You have to have some pretty sexy equipment before you’ll copy the S-band channels, and I tell you … you won’t copy anything on the Ku-band links. Dial up the old “Project Mercury” UHF channels, which the Shuttle uses as a backup, for when they can’t access one of the TDRS satellites, or when the main channels are otherwise “tied up”. The UHF channels are also used during blastoff (launch) and during all spacewalks.

Unlike the other equipment, the EVA (Extra Vehicular Activity) packs in the space suits they use on the walks are not communications encrypted. It’s all in the clear and able to be copied on your scanner, using any half decent antenna. Some monitors can even copy the Shuttle using nothing more than a hand held scanner with its stock-standard rubberised antenna.

Spacewalks are in Duplex Mode, with Astronaut “A” using channel (Mode) A to transmit and B to receive. His offsider in space uses channel B to transmit, and A to receive. They transmit continuously, unless they select backup mode, in which case communications are simplex. Power output is 250 milliWatts (a quarter of a Watt!) But at between 100 to 200 nautical miles above you, there is no problem with that small power being used. You will hear it, as long as the Shuttle is orbiting directly overhead at the time!

Shuttle Mode A Modeb Backup

296.8 (T) 259.7 (T) 279.0 (T) 259.7 259.7 (R) 296.8 (R) 296.8 (R) 296.8 279.0 (R) 279.0 (R) 259.7 (R) 296.8

Also check out 136.8 MHz, 140 kHz, and 200 kHz. And then there’s the Shuttle Amateur Radio VHF (2 metre) frequencies: 145.550 MHz (TX), and 144.91 (RX), with additional RX 144.93, 144.95, 144.97, 144.99, and while over Europe 144.70, 144.75, and 144.80 MHz. Shuttle packet communications (computer keyboard data link) are on 145.825 MHz.

There are some HF channels re-transmitting Space Shuttle audio during non-Defence related missions: 3860, 7185, 14295, 21390, 21395, and 28650 kHz, in USB mode. You can also hear Cape Radio talking to Ascension Islands Tracking Station on 20192, and Ascension Islands speaking to ships and planes involved in support the Shuttle missions on 5190, 10780, 5810, 9002, 13218, 13480, 19640, 19990, 19995, and 22760 kHz.

With the MIR Russian Space Station, tune them up on VHF Salyut frequencies 142.4, 142.4175, 142.6, 143.144, 143.625, and on amateur radio 2 metres channels 145.525 and 145.575.

When the Space Shuttle and MIR are next interacting, their docking operations can be heard on 121.75 FM, and 130.1625, these frequencies being Soyuz ferrycraft channels. Power is either 100 milliWatts, 5 Watts or 10 Watts. Expect to hear a blend of Russian and English on air!

Ian Hewson of Canberra wants to pose a question. He states “On domestic flights, the last three letters of an aircraft’s registration are used as the callsign, however for international flights, this is replaced by the callsign of the airline plus a flight number suffix. How do I know what actual airliner is being used when International aircraft use their flight numbers on the radio for a callsign?”

Well Ian, that’s why HF listeners collect selcal codes from aircraft. When an international airliner calls up on HF preflight for a selcal check, they frequently say their selcal code. If you already have a list of codes, matched to airliner registrations in that particular fleet, the problem is solved.

I personally like the American idea of having all airline aircraft identify with flight numbers. I thought that we were going to see it here on the merger of Australian Airlines into Qantas Airways, but it didn’t happen. But there are many other radio monitors who desperately want the present system to continue, because they find it very easy to keep track of domestic airline aircraft. Their argument is that by obtaining airline timetable booklets, they can work out from the times departed or arrived and the route flown, frequency used etc. what the flight number is for a particular airline registration.

American Airlines is very well aware that it is lagging behind many of its major competitors in the airline industry when it comes to the fitting of satellite technology and the resultant interactive passenger services. But was this lapse just poor management? Was it a failure to see … the future? No it wasn’t! American Airlines has been well aware of the satellite technology revolution within the airline industry. But it took a decision early in the piece to wait and see how the technology developed, and when it is sure it has developed to the point of perfection, it will move in and buy the best and latest of the proven equipment!

Northwest Airlines got its fingers singed when it encountered major teething problems with its newly fitted Hughes Avicom Interactive Data Management System, which is known as IDMS. The problems were so severe that in September 1994, Northwest deactivated the system, at a cost of many millions of dollars. 86 Australian Aviation October 1995 American Airlines, meanwhile, stood back and watched, and evaluated systems by Matsushita, GEC Marconi, and B/E Aerospace Systems. Another airline being terribly careful not to buy until the product is right is British Airways.

And speaking directly about the satellite components, Collins Commercial Avionics from Rockwell International has supplied SAT-906 systems for a Virgin Atlantic Airways Airbus A340, and an All Nippon Airways Boeing 767. Last year, Virgin made the choice of the Rockwell Collins SAT-906, married to the Bendix/King/Dassault Electronique SAT-48 low profile satellite antenna, to be eventually fitted to four Airbus A340s and two of its Boeing 747-400s. While All Nippon is opting for the SAT-906 six channel satellite system, it has chosen the Ball Aerospace satellite antenna. All Nippon already has two 747s up-and-running for full satellite communications.

Gordon B Wilson is primarily a dental surgeon. He’s also an “On the Airbands” reader, and a keen monitor of the airline airwaves. This contribution was overheard on a company frequency which Gordon prefers to keep to himself. But he is more than willing to share the content of the story with us. And believe me … Gordon has every reason to take an interest in this story. It’s something he can really get his teeth into … you might say!

Aircraft First Officer

“One of our passengers has just been ill in one of the rear toilets. They’ve compounded the problem by throwing in their teeth as well! I would like someone on hand to look for these articles on arrival please.”

Gordon could not hear the reply from the Company, but the remaining words from the flight deck a few seconds later gave him a fairly good idea of what had been said!

Aircraft First Officer

“No way … I’m not joking. Yes … I understand it could well be a search-and-destroy mission!”

Knowing how partial people are to their teeth … Gordon wonders if anyone except himself (being a dentist!) will find this story amusing. Don’t know Gordon!

Our last item this month allows us to visit Maitland Airport, courtesy of an anonymous pair of contributors, who collaborated to get the story down pat. We’ll call our people Joe and Pete. Both gentlemen have Unrestricted Private Pilot’s Licences, and on this Sunday morning, Joe was occupying the left seat. As they approached the field, Joe allowed Pete to fly the descent and join up with the circuit.

Joe was listening to another aircraft in the circuit, a Cessna 152, and he recognised the voice of the CFI (Chief Flying Instructor) on board. Joe made the call joining crosswind, with Pete still flying, and watched the Cessna 152 with the CFI slot in behind. Joe said to Pete: “Make it a neat and tidy one mate, the CFI’s behind us!”

Then to Joe’s horror, he realised the transmit light was still illuminated, and his press-to-talk (PTT) switch had been jammed on as he warned Pete about the CFI being behind them. He thought carefully, and realised they hadn’t used any colourful language. As soon as the button was freed, the CFI on the Cessna 152 replied: “I’ll watch your landing with great interest!”

The moral to this story: Always check your transmitter PTT switches before you talk idly in the aircraft. You never know who could be listening. Maybe even one of the monitoring fraternity hooked on every word of this column!

Talk to you again in the circuit in November. Enjoy your monitoring and write to me with your stories from the aviation bands, regardless of how long ago the situations occurred. Send your contribution to me, at PO Box 16 Georges Hall 2198.