Machine kaputt

(translated by Juergen Matthes)


One of the highlights working for Air Traffic Control was the fact that we were entitled to the so called ‘experience flights’, in our jargon called SE-Flug. In regular intervals, about every two years, we were assigned to an SE-flight by our ‘belle etage’. These flights, which you participated as a fully accounted cockpit crew member (without a ticket), were supposed to provide experiences and views into the workload of the flying crew in all imaginable situations. Therefore you participated in a whole rotation together with the crew.

It was logical that these flights were supposed to be provided for the operational staff of ATC only. Unfortunately the ‘belle-etage’ managed time after time to assign members of the administrative staff to one of these flights. Of course the crew noticed the missing operational background of such a person and was, so to speak, not amused!

It was my turn again, I was presented with a rotation Frankfurt – Nuremberg – Frankfurt – Vienna – Frankfurt. The aircraft was a Boeing 727. At that time I was working at Karlsruhe UAC (radar control unit working the upper airspace above 25 000 feet), radio callsign Rhein Control.

Such a rotation comprises everything the cockpit-crew is required to do, including several briefings, that meant getting up early to be on my way for Frankfurt!

First you visit dispatch, get flight-plan data, fuel, weather data. Then the cockpit-briefing takes place, it deals with emergency procedures and also my role in them: I therefore got an introduction to the usage of the oxygen mask, learned to operate the intercom and radio panel and got familiarized with the security belts / harness and the handling of them. All that took place in the terminal.

Then briefing with the cabin crew. Once again emergency procedures, and most important: What’s for lunch! After that taken care of, Lufthansa crew bus took us to the aircraft.

Since the plane had just been through its mandatory check in a hangar, I skipped outside check, I didn’t want to miss how a ‘cold and dark’ airplane was brought back to life.

Our captain was, like you always picture a captain: tall, serious, white streaks in his hair, with a deep, calm voice. Very impressive! The co-pilot (nowadays first officer) was the exact contrary: A tendency to being a bit overweight (I try to be polite), jovial, frankonian dialect, but somehow a bit unpleasantly importunate, a real smart alec. On the 727 there still were flight-engineers, those are always the same type of persons: tall and lean, as you know them from submarine movies!

After the captain had conducted takeoff in Frankfurt, he handed control over to the co, who was supposed to fly the aircraft until Nuremberg including the landing. The crew didn’t show any specific interest in me, except for the flight engineer (FE). I didn’t mind though, since I liked to watch, and the FE explained quite a few things which were new to me.

About 15 minutes before landing the co, now acting as pilot in command (PIC, nowadays pilot flying) was going through the landing preparations. For that he slid his seat back as far as it went, and then he even cranked down his back rest until it was almost horizontal. Lucky me, I was sitting behind the captain, otherwise I would have been crushed! Then the co leaned back, he almost looked like a first class passenger relaxing and waiting for service. I only thought, he doesn’t have any more outside view, strange.

The two up front were discussing the landing now, I didn’t understand a word, but I have to admit, I didn’t try hard either, because I was curious how one can land an aircraft from such a sitting position!

At 10 miles final we were on the ILS. Since I had ridden up front several times before, I noticed an excessive angle of attack of the aircraft right a way. When I looked back into the cabin (at that time the cockpit door was still supposed to be open), all passengers seemed to be downhill, way below me!

Maintaining this angle of attack we touched down on the runway. The co kept pulling the yoke, more and more, towards himself, this explains his sitting position, and this kept the nose up. When the aircraft couldn’t hold this attitude any more, the nose slammed onto the runway and the bird decelerated using only the brakes, without using the reversers.

We had landed, but how had we landed! How the co could see the runway from his sitting position – remained his secret, I could hardly try for myself how you could see outside from his seat. From the pale faces of the passengers leaving the plane I concluded that they counted that landing as almost a crash.

The crew continued to ignore me, for sure they had had some administrative couch potato along on their last experience flight and were fed up, so I decided to accept the offer of the FE to go along for an outside check. The mickey mice (hearing protection) were put on, then outside! We checked the landing gear, especially the tires, the APU, the leading edges of the wings, the flaps and the sensors.

Then we went back inside via the aft staircase. On both sides, in the tail of the aircraft, were small doors which puzzled me, so I asked the FE. They were to be able to check the engines in the tail, did I want to have a look. Sure I did, when else could you have a look at something like that.

He opened the right door and cleared the way. “Look at the fan blades”, he stated, “they must be bent, but consistent”. And there must not be any damages visible”. So I had a look and – yes – they were bent, but by no means consistent.

So I said – “boy, they are bent, but not consistent”. Then I only heard – “WHAT?!” I was shoved aside.

The FE took a long look, but came to the same conclusion: “Yes, they are bent, but crooked”! He ran to the door on the other side and tore it open. Then he shoved me towards it and said “that’s the way they are supposed to look”. I had to confirm, they looked ok. “Doesn’t help”, he said, “the technicians have to go for it”.

So back to the cockpit and report the incident. The captain called the technicians and postponed boarding by 10 minutes. I only thought “what an optimist!”

The technician came, had a look in the back and then only shook his head, someone should get to the engines from the outside with a ladder, have a look and take some measurements. Being friendly, he added an estimate right a way: It would take about half an hour. The captain passed that on to the gate: Delay!

The ladder was brought, a technician climbed it, took some measurements with a gauge, came down again, the ladder was removed. He then came to the cockpit and stated: Flying is tricky, if one of the blades gets torn off he wouldn’t like to be in the aircraft, flying with passengers is impossible.

The crew started discussing. Is there a possibility to get this fixed here at Nuremberg? If not, should we fly empty to Frankfurt? And how do the passengers get to Frankfurt? The captain decided to discuss the problem with the technical department at Frankfurt and then make a decision. So he left us and made a phone-call to Frankfurt from the terminal.

10 minutes later he was back and announced his decision: The passengers are taken to Frankfurt by bus, as well as the cabin crew. Of us four everyone should decide for himself if he wanted to fly or take the bus. He also stated that everyone who would vote for flying, would have to sign a statement that he would do that on own risk, that Lufthansa was freed of all responsibilities. Everyone voted for flying.
Since the technicians checked the other engines, we had time to get a meal from the first class trolley and leisurely enjoy it. “Last Meal!” Gosh, they talked to me, I hardly hadn’t noticed before!

Then we refueled, the doors were closed by the FE, and we prepared for startup. Clearance came from the tower and at the same time from the fire trucks. One on each side, very calming!

The FE calculated our takeoff weight and recommended to use number 3 (the damaged engine) only for takeoff and if needed for landing and otherwise let it idle. This would reduce the risk considerably of a turbine blade been torn off. The captain agreed.

The engines were running now, the FE went to the back to the described door and had a look at the engine. He tried to listen whether he could hear something unusual, but everything sounded normal. So far, so good!

We all were full of respect for the coming flight, you could tell by the lively discussions we were all having. You blabber your fear off!

We decided that I should conduct talking to air traffic control, and to hint to them that we had a “minor” problem.. “Hinting” was important, because if we would encounter a stubborn controller, he could inquire whether we would declare an emergency, if not, we should be handled as any other normal flight. Therefore it was my task to softly point out our problem and request appropriate handling.

Our air traffic control network is astonishingly efficient, because already the ground controller asked how we intended to perform taxi to the runway. So I explained that we could use engine 3 only to a limited extend, taxiing with 2 engines should be no problem, but it would be great if he could pass this information to the following controllers.

We taxied, escorted by the fire brigade, to the runway. The captain had calculated, if No. 3 would run with 80% power-setting, the length of the runway would be more than sufficient. Let’s go! During takeoff roll the FE hung over the thrust levers and paid close attention. Shortly before the end of the runway the captain carefully pulled the nose up, at least we were flying!

At positive climb No. 3 was reduced to idle, which resulted in a drift to the right, but that could be compensated by trim. Flight level 160 allowed a splendid view across the landscape passing underneath us.

Each sector controller handled us like a raw egg, they were superb, even holding (normal to Frankfurt) was not for us this time! They planned us for the southern runway in Frankfurt, we wouldn’t mess up things so much there.

Landing was not so spectacular as at Nuremberg, it was a ‘greaser’! The fire trucks were there also, they reminded us of our defect. We taxied directly to the hangar and learned from the technicians that before the flight to Nuremberg the aircraft had been perfectly ok. Bending of the blades must have happened during the flight to Nuremberg.

The flight to Vienna and back, naturally in a replacement aircraft, went pleasant and uneventful except for the order of the captain “you don’t go out of the aircraft and look at nothing no more!” Since I complained about this order, I got a great meal in first class as a compensation!

We turn the Runway Around

[translated by Juergen Matthes]

Twin Otter
Twin Otter

Naturally you don’t turn a runway around, you “switch runways”, that means according to wind directions and speeds you change the direction of takeoffs and landings. Wind still is a major factor in aviation.

As passenger in a jet you can experience this yourself. Let’s say you are on a flight from Frankfurt to Miami. You have a small portable GPS device with you, and you play with it close to a window during the flight towards Miami, right over the Atlantic Ocean. You realize your speed over ground is displayed as 400 miles per hour. You wonder, your airplane is supposed to travel more than 500 mph. On the return flight, again over the Atlantic Ocean, going east, you play with your toy again and it shows 610 mph. What’s going on?

Very easy: the airplane travels always with the same speed in relation to the surrounding airmass, about 500 mph. On your way to North America you normally will have a headwind with about 100 mph, this results that you travel that much slower. On the way back you travel with 500 mph in an airmass moving itself with 100 or 110 mph in your direction of flight, therefore you are now faster (over ground).

This effect has to be considered during takeoffs and landings. You take off and land preferably against the wind. Number one – it is safer, and number two – you save some fuel. A takeoff with a tailwind means the airplane has to accelerate to a higher speed to achieve the airspeed needed for flight. Let’s say you need an airspeed of 120 knots for take off, a tailwind with 10 knots prevails on the runway, so that requires a speed of 130 knots (on your wheels) to achieve 120 knots airspeed. With a 10 knot headwind you only need a speed of 110 knots (on your wheels).

So it makes sense, to adapt the directions for takeoffs and landings to the wind conditions. Therefore wind and its constant changes is an important factor on any control tower. Now the wind at an airport normally hasn’t the desired effect to reverse its direction completely to the opposite within a short period of time. No, wind acts as it pleases! So it is the responsibility of the tower-crew, to constantly monitor the wind, its tendencies of direction and speed, and to switch runways if needed.

Düsseldorf Tower, a nice day, the wind blows from the west with 15 knots. Approaches and landings are proceeding towards the west, as they normally do under these conditions. The weather bureau has forecasted a change of wind towards the north-west within the next 20 minutes.

This is no problem for takeoffs, they will a bit more jerky. For landings it is a different story, they have to point their nose into the wind (crab angle) until shortly before touchdown when they will straighten out the airplane. For us in the tower cab this is great, we have something spectacular to watch! It is always interesting to watch such landings with a crosswind component.

The wind continues to shift towards the north. Now a good crosswind, the pilots have to show their skill! For crosswinds we have specifications in the tower we have to follow, dictating which strength will require the airport to be closed. But – it’s a long way until that will happen.

But if the wind continues to shift to the east, we will have to switch runways. Naturally it continues to drift to the east. Good air traffic control service means, to be able to handle all imponderabilities and yet provide an orderly and safe flow of air traffic!

The imponderabilities today – it is the period of rush hour, so very high traffic density. The tower controller, the feeder (he is responsible for the sequence of approaching aircraft) and the two approach controllers (handling the northern and southern sectors) are now discussing the best timing to switch runways.

Most times this will result in the statement “after landing of the KLM you can go ahead and switch”. The apron controller guides all aircraft ready for departure from now on to the western end of the runway and strings them at the holding point of the “new” runway.

Feeder announces the KLM arrival at 10 miles final, and there she calls in on tower frequency.
Tower: “KLM 83, Wind 050 with 15 (knots), cleared to land runway 24.”

To understand the following, you must comprehend the relations of speeds. Everyone knows this situation, you are driving on a freeway with 85 mph and suddenly you see a speed-limit sign showing 50 mph. What will you do? Some will take their foot off the gas-pedal and let the car slow by itself until it reaches 50 mph (or slightly faster). They take into consideration that they might be speeding well after the speed-limit sign, but this procedure will aid the traffic flow because nearly everybody is acting like this. But there are also those who will step on the brakes passing the sign and therefor obey the speed-limit precisely.

Both behaviours are present in aviation too. We also have speed-limits, which have to (should) be obeyed. Approaching an airport there is a limit of 250 knots IAS below 10 000 feet, then minimum clean (the slowest speed an aircraft can fly without deploying flaps) and finally any speed-limit an air traffic controller issues to ensure separation to other traffic.

In ATC even small errors get on your back, sometimes a bit later, but they surely do! The decision to switch runways after the landing KLM and the designated time gap before the first landing on the new (now opposite) runway had been selected a bit too short! A Lufthansa Airbus A310, who called in at 10 miles final to the runway facing east, was way too early.

KLM, on the other side, was a slowpoke! She was overly correct and had slowed like stepping on the brake when getting the first glimpse of the speed-limit sign, in short she still needed a while for her landing.

The situation was now (pardon my language) – shitty! KLM was on final westbound, Lufthansa A310 on final eastbound (remember: same physical runway), approximate meeting point was the western end of the runway. This constellation is called a “double decker!”

Solution to this problem is quite easy: You instruct the A310 to go around (overshoot), a sharp left turn afterwards, but you cannot be sure that it will work out. KLM could be forced to overshoot as well (by some unforeseen factor), and then you would have a near miss or even worse!

In our case all went well, the Lufthansa A310 overshot and thundered across the hospital, KLM landed safely! Right away the telephone connecting the tower to the outside world rang, and sister Agate (one of the head-nurses of the hospital) was on the line complaining about the tremendous unbearable noise.

This telephone-call, which happened every once in a while, was major punishment for all of us up here! Sister Agate was always right! She chewed us, kings of the airport, up and spat us out in pieces! What a disaster to our confidence.

I had the (doubtful) pleasure to get to know sister Agate personally, she actually was a fine woman taking care of her patients. After I explained to her, that we also took care of our clients, she relaxed a bit and future telephone calls from her were less mortifying …