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From the Tower looking Back ....How to (legally) stretch your fuel

By Rob Russell

I remember that Sunday, in 1984. I had just been signed out on Approach and Area and I was young, keen and full of no knowledge at all! After all, I had just completed a three-month theory course and had done about 100 hours of dual, so I thought I knew it all.

But as in just about any other profession, there is the book and then there is “let me tell you how it actually works!” I had found out, as my training went along, how the latter did not always agree with the book. The one thing I can clearly remember about my on the job training was from one instructor who asked me if I could remember all the stuff they taught me at the College. Oh yes, I keenly replied – I mean after all one should! Well, he replied, take it and leave it in the rubbish bin at the front entrance. We are here to teach you how to do it properly, he said.

The wind that Sunday, was a gentle north-westerly – I think it was about 15, maybe 20kts, a lovely spring day and runway 01 was in use. In those days, there was not much traffic on a Sunday morning and the highlight, if one could use such words, was the SAA SP from London, which arrived about 1030. In fact, there was not much traffic at all!

Being a Sunday morning, and there not much going on, we combined the area and approach sectors – you could do it in those days. I remember when I first qualified; there were a total of 12 controllers that worked at Cape Town ATCC. Not hundreds like today! It was not uncommon to work Tower, Approach and Area at the same time – three sectors and one controller. Never a problem and we were always keen to do it – especially us youngsters. We wanted hours and Sunday was always a bonus, as it was overtime and extra pay. The older chaps were only too happy to give up a Sunday to us youngsters!

Gosh those were the days, but I digress

Back to that Sunday morning, in September. One of the things we were taught is that aircraft land and take off into the wind. If my memory serves me correct, there were a total of nine factors that we took into account when the runway was decided, and the wind direction and strength were near the top. It was quite safe to land with a few knots tailwind. Ask any pilot and they will tell you that if the controller says the wind is light and variable, you must expect a ten know tailwind!! Not like nowadays, where the Tower controllers would think nothing to change the runway if the wind went from northerly at 1 knot, to southerly at 1 knot!

In those days we only had radar coverage up to 140 nm from Cape Town – and that was on a good day and depended on the technician on duty! The surveillance radar was sited about where stand B20 is now on the apron. It was half-buried in the ground – what for no one could really tell me either!

So this blip appeared on the radar at about 140nm North West of Cape Town. It could only be SAA231 from London – it was the only time we saw aircraft up there. I duly made contact with the aircraft and told them it would be radar vectors for runway 01 and the weather was partly cloudy with a northwesterly wind of not very strong. The usual stuff one tells an aircraft on the first contact, The youngish voice sort of acknowledged it and it went silent. After a few minutes, he came back and asked for straight in onto runway 19, ie landing from the north. I can remember his voice was a bit nervous and short. No, I said! It was runway 01 in use and it would be radar vectors.

As I said earlier, about choosing a runway one of the other factors was the traffic flow. It wasn’t really busy at 1030 on a Sunday – so either runway was available, but the wind favoured runway 01, ie an approach from the South.

The pilot made another request for straight in on runway 19 and again I said runway 01. After all, I was full of newfound knowledge and thought I knew what I was talking about. There was a silence of another minute or two when the decidedly older voice appeared on the frequency. Ah, the Captain was now awake and around up there! I was about to learn very quickly about the SAA re-dispatch procedure.

“Youngster” came this old voice “ we are landing on runway 19 and there will be no more discussions about this on the frequency”! Roger, I replied, or at least I think I did!

A quick look around at my more senior and older colleague and I asked for help. Oh, he said – welcome to the re-dispatch system! I had heard about this system, whilst I was on course but did not really pay much attention to it or what it meant and how it worked.

In essence, a flight is required to have enough fuel to fly to its destination, hold somewhere for a certain length of time if there is unfavourable weather and then divert to a nominated alternate airfield and land there, if unable to land at its destination. These two airfields were also put on the flight plan, so ATC could see them. There was no stipulation as to where the alternate airfield has to be. It could be any airfield, as long as it was in range of the destination and the aircraft had the fuel to be able to get there.

One must also remember that the first generation of wide-body jets did not have the most fuel-efficient (nor quiet) engines. In those days, fuel was dirt cheap and easy to get hold of, and they weren’t built to keep Gretha’s grandparents happy and quiet. They were actually of no importance in those days and airlines paid very little if any attention to their occasional mutterings. So efficient engines were not high on the list of choices, as they are now.

Another factor that SAA had to take into account, which was very much out of their control, is that they could not fly over Africa and had to fly around the bulge. That meant on many northbound flights, they had to stop over at Illa de Sol, to uplift fuel, as they did not have the range to get to many of their destinations. A massive inconvenience and added a few hours on to the flights. Of course, the crews did not mind! A few days of the island, some extra allowances and a fine time was had by all.

Southbound was a completely different kettle of fish. They could not legally get from London to Cape Town, without having to stop along the way to uplift fuel. However, it was only a matter of time before someone came up with the clever idea of filing a flight plan to a point en-route and using Cape Town as the alternate airfield. It was perfectly legal and within the legislation. So that is what SAA came up with. What, in effect happened is that for years they filed a flight plan to Windhoek, from London and Cape Town became the legal diversion airfield. Within the law, and nothing wrong with it at all.

The flights were filed by a, what was to become a very well known point, at 18South and 10 east. This was the southwest corner of Angolan airspace and the northwest corner of Windhoek’s airspace. At that point, the crew did some calculations, took into account the weather from there to Cape Town and in consultation with their despatch office at Johannesburg made a decision to divert to their alternate. Perfectly legal and nothing wrong. There was nothing that said you could not fly direct to your alternate airfield. And so that is what happened, that morning. A decision was made that there was enough fuel on the aircraft and rather than turn left and go to Windhoek, they flew onto Cape Town.

(The same procedure was used to their flights to Johannesburg. Except than rather than land at Windhoek, they overflew it and carried on to Joburg. That same procedure is now still used by some airlines and has become refined and a well developed and safe procedure.)

So that fateful Sunday morning the aircraft carried on down to Cape Town, but either they hit unexpected headwinds, or the tailwinds were not there, but when it came to "top of descent" there really was not much fuel on board to fly the whole approach from the south. Hence a few nervous voices from the cockpit, me frantically getting a crash course in how the re-dispatch system worked and an approach from the north!

As I muttered earlier, Sundays were known for not much traffic and we were able to safely accommodate the SP landing on runway 19. I can remember remarking how much quicker it looked on final and also being a bit higher than normal. But I am sure the crew had everything fully under control up there! It landed what appeared to be a bit faster than normal and used a bit more runway to stop, but it got down onto the ground safely and without any incident. One thing I can remember is a colleague saying their voices seemed noticeably less tense and relaxed once they had gotten on the ground!

In those days, the SAA engineer’s apron office was known as the hut. Cape Town was a small airport and everyone knew everyone and we all knew where everyone worked. I had a break a few hours later and took a drive down to the hut, determined to find out more about this procedure. The hut was an appropriate name for their office, It was literally a hut, situated alongside the temporary international building, which is now roundabout where stand A6 is. I asked the duty engineer, Smithy, I think it was – most of them had that nickname – what was the reason they landed on runway 19 and all he muttered was something to the effect that the aircraft had arrived on not much fuel and the crew needed fresh underpants!

I think there were a few relieved flight crew members that day and a very happy bunch of passengers who arrived in Cape Town blissfully unaware of how tense things had been up in the cockpit!

Of course with the second, and subsequent, generations of wide bodies, engines became very efficient things and ranges increased substantially and hence they were able to legally fly to Cape Town without having to use this system.

The area around 18S10E later became an infamous point. It was on the 13th September 1997, when a Luftwaffe Tupolev 154 passenger jet routing from Niamey to Cape Town and a USAAF C141 Starllifter transport aircraft, routing from Windhoek to Wideawake Island was involved in a fatal mid-air collision, with the tragic loss of 33 people. With the modern technology that is available to aircraft nowadays, such a tragedy would not have occurred, of that I am sure.



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