Navigation, the art of getting lost – Part 1
Faultless navigation plays an all important role in the safe operation of aircraft. There are scores of instruments both in the cockpit and on the ground, the purpose of which is to make sure that pilots and controllers are constantly aware of where their airplanes are flying. Of course, not all the available systems are of equal sophistication, while some provide direct readout of position, others require quite a bit of interpretation. Different aircraft may have different equipment installed and under certain conditions controllers on the ground are the only ones who can really tell at a glance the position of a particular plane.
Constant positional awareness of the flight crew is helped by specialized charts quite unreadable to the layman. What you see is a maze of lines, circles, symbols, figures and arrows, but to a pilot they tell all he needs to know. Controllers mainly rely on their radar to keep track of what is happening but they can read a navigation chart as well as any pilot can. Still, navigational errors do occur, almost always leading to hot situations in the cockpit and on the ground. Here are a few of the more notable ones from our experience.
Shitbombers and the mountains
If you loose your way in the sky while flying over flat ground on a bright summer day, though awkward, things are not likely to take a nasty turn in a hurry. You can always try to read the name of a nearby railway station or if this fails, call in to ATC for some friendly advice. However, if there are mountains around, you are flying in clouds and radar has difficulties tracking your flight, it is better to watch your every step.
Remember the old Chinese saying “Luck never comes in pairs or disaster alone”? Well, this seems to be especially true for flying. The five shitbombers (we called the agricultural sprayers shitbombers) were plodding along in a tight formation, heavily loaded with fuel, on a ferry flight bound for the Middle East.
They were also flying low, just about maintaining a safe altitude above the mountains surrounding the Danube-bend. They must have had a spectacular view of that lovely, wooded area. As they were so low, our radar had difficulty following them, and we kept loosing their track on the screen. Radio contact was Ok, however, and they reported passing all the right beacons, so there had been no cause for concern. Even with their rudimentary instrument-fit, they should have been able to stick to their planned route. They should have been, had the lead aircraft’s navigator not made an error in dialing in the frequency of the next ground beacon. He had, however, and not being familiar with the route, they blindly followed a track to the wrong beacon, a track that diverged from their route by almost 45 degrees.
By now radar had lost them completely. Due to their slow speed it also took us several minutes to realize that something was wrong. Very wrong indeed, if the readings from the automatic direction finder (ADF) were anything to go by. This clever little instrument gave a digital readout of an aircraft’s bearing from our station each time the pilot transmitted on his radio. As we were getting worried, a series of questions and answers flashed back and forth between the controllers and the shit bombers and by simple geometry it was easy to see from the ADF indicator that the little birds were all over the place, except where they should have been. To make matters worse, they were heading towards an area where a combination of even taller mountains and lower cloud ceilings were waiting, like a deadly trap, ready to jump.
The flight leader must have been surprised when he heard the instruction to reverse course and climb, but the urgency in the controller’s voice convinced him this was no time for arguments. As their altitude increased, radar finally picked them up – almost a hundred miles off track, but at least plodding back away from the mountains. A few messages later it was our turn to be surprised, however. Concerned with their fuel state, the shitties wanted to know the reasons for the “detour”, and in the course of the explanation they finally admitted that they were flying without a map, all they had was a makeshift list of beacons to follow. How the off-route beacon’s frequency managed to get into the list was anybody’s guess…
With the help of radar we did managed to put them on the right road once again, but we could only hope their list contained all the right beacons for the rest of the route. It must have, for a few months later we received a real fancy postcard, mailed from Africa, thanking us again for the valuable help. Well, it is all in the day’s work folks…
Sightseeing with BEA
In most cases, flight crews will not argue with a controller’s instructions. But there were flight crews who followed this rule to a fault. These will follow instructions received from air traffic control to the bitter end, even when a query put in edgewise would save the day. Pilots of British European Airways (anybody out there still remembers BEA?) had always been the epitome of discipline who very rarely, if ever, complained about anything. Used to busy Heathrow, they were not easily jolted out of their legendary calm.
On this particular day approach control wasn’t overly busy, and the BEA Trident had been given a heading that would take it a few miles east of and parallel with the runway. As they were descending to 2000 feet, the radar controller set about bringing in a few more arrivals. The British captain reported reaching 2000, but as approach was not yet ready to turn them in, they were instructed to continue on their assigned heading. This they did, and as time slowly passed, so did they pass out of radar coverage. How and why the controller managed to forget that there was another fella out there, we will probably never know, but the fact remains, he did forget. And good old BEA just flew on and on, as told, never doubting, never questioning…
I do not rightly know what might have happened, had the operations officer of a military airport about fifty miles downwind from our field not telephoned, complaining about a low flying jet, with nice red wings, disrupting his local traffic. This immediately rang the correct bells and the Trident was turned back towards our airport, to land safely twenty minutes later (and half an hour late…), as if nothing untoward had happened. Typically, the British captain didn’t say a word and there was no written complaint either.
Oops… wrong runway
Getting lost while flying on instruments probably looks like the natural thing to a layman. What with all those dials and unintelligible gibberish coming from the radio, getting lost is the natural consequence… Every controller and every pilot knows, however, that the opposite is true. You learn to read your instruments and you grow to trust them. Eyeball navigation is nice but it has its limits.
Finding the runway at the end of an instrument flight is not a particularly difficult task, especially since the introduction of the Instrument Landing System (ILS), on which you can fly your bird to touchdown with more precision than backing your car into your garage. We, the controllers, will vector the aircraft onto an intercept course for the appropriate ILS, and from then on the pilot can do his bit without sweat. As each runway’s ILS operates on a radio frequency unique to that runway, there is little danger of landing on runway “A”, when you wanted to go to runway “B”.
This is the theory. In practice, when the visibility is good, a lot of pilots were tempted to revert to the good old procedure of a visual approach. If the airport is not particularly busy, it is a fair bet that sooner or later a request for a “visual” will come in from one of the big birds. Most airlines require that all approaches be made on instruments, regardless of visibility, but only a few expressly forbid visual approaches. So, the temptation is high, after all no pilot worth his grain is immune to the exhilaration of hand-flying a multi-engine jet on a short visual approach. To watch such an exercise is equally fascinating for the controller, so if circumstances allow, we are glad to oblige.
This had been exactly the case on that quiet Saturday afternoon when the pilot of a certain European airline reported having the runway in sight, at the same time requesting clearance for a visual approach. With no clouds around and unlimited visibility, approach control promptly transferred the flight to the care of the tower. As there was no other aircraft within a hundred miles, approach never bothered to take a second look on their radar to check where their former charge was actually going.
With things so very quiet, the tower had issued the clearance to land although they could not at that time visually spot the incoming machine. The fact that there lurked a military field a few miles west of ours, with the same runway alignment, did not seem to enter the picture.
As time passed and there was still no sign of a plane gliding towards the runway, the tower controller finally requested a position check from the pilot. The reply “Two miles out, on final, ready to land.” came in a completely self assured manner, momentarily throwing the controller off balance. He still could see no plane on final, but if the captain says he is there. ..? His confusion only increased when a few seconds later the same captain reported having landed… and then continuing in the same sentence with a report of being airborne again on a south-easterly heading, requesting radar assistance. All this time there wasn’t a shadow of a plane to be seen anywhere.
Later we could only bless those military engineers who had built their runway long enough to make such a touch-and-go by a heavy commercial bird possible. Of course, our captain had spotted the military field’s runway and once committed to eyeball navigation, they never bothered to tune their navigation sets to the civilian beacons. These would have shown them the progressive divergence from the proper track. As they have never before landed at our field, the first sign of something amiss had been the nice rows of fighters peacefully parked in front of their shelters. This was more than enough to send our flight back in the air as fast as her engines would take her.
If you think the approach controller had paid less attention to his duties than he should have, you are right. But consider this. The military controllers never complained of an extra flight making a touch-and-go at their field…
Speaking as an ex-BEA Trident driver, I might admit under extreme pressure that there were those among us who would never say Boo to an ATC goose… but they would almost certainly be in the minority in that three-crew cockpit. The Trident was equipped with a (then, 1960s) state of the art Map Display, a device that used a paper roll chart to scroll through the route with navigation data supplied by a Doppler radar and gyro heading . It was the job of the third pilot, P3 (who sat in what in other airlines would have been the engineer’s position, but we were always different), to set up the system, to change charts as required and to update the position if needed when a suitable fix was available. As a precise navigator it hardly compared to GPS, but as a situational awareness device it was fantastic. So the crew you mention may well have politely declined to complain about the lousy vectoring, but they were probably very well aware of where they were. BEA was responsible for a lot of innovation, Fail Op Cat lll for starters, but for 40 years we also had approach charts with deceptively clever terrain contours, of which Jeppesen has managed only a poor imitation only recently, and whihc helped raise terrain awareness to a point that even GPWS cannot meet.
Alex,
Back then we were not allowed to come anywhere near the aircrat of a Western airline and I do not think anyone was really aware of the degree of sophistication in the Trident cockpit. What did know was that BEA crews (and later British Airways) almost never complained about anything. This had the curious side effect of controllers bending over backwards to give BA flights the best possible service at all times (within the available capabilities to be sure). The incident I described was a cock-up that did not happen often:))))
The Budapest TMA was often described as a deep hole surrounded by mountains… The minimum entry and exit levels were around FL140 and 160 and the distence to the airport was fairly short. Aircraft types that were not too good in descending (excess speed like the TU-134) or in climb had to do a lot of fancy footwork to satisfy the restrictions around the TMA. Most of the complaints came from airlines who for some reason were not aware how crazy the set up really was. I remember clearly how appreciative were were of crews who helped instead of complaining. BEA and later BA were certainly among those who helped.
The station manager was an ex-pat Hungarian and he was also the chair of the airline reps committee at the airport. He was a very polite gentleman and used to come to see our boss regularly to present the airline “wishes”. Afterwards, he would drop in to approach control and chat with the controllers. He was a good diplomat…
I am not sure how they feel about BA these days but back then BEA was seen as politeness incarnate.