PRELUDE
Charles Svoboda's Story of 1965
This is a true story narrated by a copilot about professionalism and I have used it to set up the base for my story about flying in zero-zero weather.
It happened sometime in 1965, in Germany. I was a copilot, so I knew, everything there was to know about flying, and I was frustrated by pilots like my aircraft commander. He was one of those by-the-numbers types, no class, no imagination, no “feel” for flying.
You have to be able to feel an airplane. So what if your altitude is a little off, or if the glideslope indicator is off a hair? If it feels okay then it is okay. That’s what I believed. Every time he let me make an approach, even in VFR conditions, he demanded perfection.
Not the slightest deviation was permitted. “If you can’t do it when there is no pressure, you surely can’t do it when the pucker factor increases,” he would say. When he shot an approach, it was as if all the instruments were frozen – perfection, but no class.
Then came that routine flight from the Azores to Germany on our C-124 Globemaster. The weather was okay; halfway to the European mainland, the weather started getting bad. I kept getting updates by HF radio. Our destination, a fighter base, went zero/zero. Our two alternates followed shortly thereafter. All of France was down. We held for two hours, and the weather got worse. Somewhere I heard a fighter pilot declare an emergency because of minimum fuel. He shot two approaches and saw nothing. On the third try, he flamed out and had to eject.
We made a precision radar approach; there was nothing but fuzzy fog at minimums. I started to sweat a little. I turned on the instrument lights. When I looked out to where the wings should be, I couldn’t even see the navigation lights 85 feet from my eyes. I could barely make out a dull glow from the exhaust stacks of the closest engine, and then only on climb power. When we reduced power to maximum endurance, that friendly glow faded. The pilot asked the engineer where we stood on fuel. The reply was, “I don’t know… we’re so low that the book says the gauges are unreliable below this point.” We didn’t carry parachutes, so we couldn’t follow the fighter pilot’s example. We would land or crash with the airplane.
The pilot then asked me which of the two nearby fighter bases had the widest runway. I looked it up and we declared an emergency as we headed for that field. The pilot then began his briefing.
“This will be for real. No missed approach. We’ll make an ILS and get precision radar to keep us honest. Copilot, we’ll use half flaps. That’ll put the approach speed a little higher, but the pitch angle will be almost level, requiring less attitude change in the flare.”
Why hadn’t I thought of that? Where was my “feel” and “class” now?
The briefing continued, “I’ll lock on the gauges. You get ready to take over and complete the landing if you see the runway – that way there will be less room for trouble with me trying to transition from instruments to visual with only a second or two before touchdown.” Hey, he’s even going to take advantage of his copilot, I thought. He’s not so stupid, after all.
“Until we get the runway, you call off every 100 feet above touchdown; until we get down to 100 feet, use the pressure altimeter. Then switch to the radar altimeter for the last 100 feet, and call off every 25 feet. Keep me honest on the airspeed, also. Engineer, when we touch down, I’ll cut the mixtures with the master control lever, and you cut all of the mags. Are there any questions? Let’s go!” All of a sudden, this unfeeling, by the numbers robot was making a lot of sense. Maybe he really was a pilot and maybe I had something more to learn about flying.
We made a short procedure turn to save gas. Radar helped us to get to the outer marker. Half a mile away, we performed the Before Landing Checklist; gear down, flaps 20 degrees. The course deviation indicator was locked in the middle, with the glideslope indicator beginning its trip down from the top of the case. When the GSI centered, the pilot called for a small power reduction, lowered the nose slightly, and all of the instruments, except the altimeter, froze. My Lord, that man had a feel for that airplane! He thought something, and the airplane, all 135,000 pounds of it, did what he thought.
“Five hundred feet,” I called out, “400 feet……..300 feet…….200 feet, MATS minimums….. …….100 feet, Air Force minimums; I’m switching to the radar altimeter ……..75 feet nothing in sight……50 feet, still nothing….25 feet, airspeed 100 knots,”
The nose of the aircraft rotated just a couple of degrees, and the airspeed started down. The pilot then casually said, “Hang on, we’re landing.”
“Airspeed 90 knots….10 feet, here we go!”
The pilot reached up and cut the mixtures with the master control lever, without taking his eyes off the instruments. He told the engineer to cut all the mags to reduce the chance of fire. CONTACT! I could barely feel it. As smooth a landing as I have ever known, and I couldn’t even tell if we were on the runway, because we could only see the occasional blur of a light streaking by.
“Copilot, verify hydraulic boost is on, I’ll need it for brakes and steering.” I complied.
“Hydraulic boost pump is on, pressure is up.” The brakes came on slowly---we didn’t want to skid this big beast now. I looked over at the pilot. He was still on the instruments, steering to keep the course deviation indicator in the center, and that is exactly where it stayed.
“Airspeed, 50 knots.” We might make it yet.
“Airspeed, 25 knots.” We’ll make it if we don’t run off a cliff. Then I heard a strange sound. I could hear the whir of the gyros, the buzz of the inverters, and a low frequency thumping. Nothing else. The thumping was my pulse, and I couldn’t hear anyone breathing. We had made it! We were standing still!
The aircraft commander was still all pilot. “After-landing checklist, get all those motors, radar and unnecessary radios off while we still have batteries. Copilot, tell them that we have arrived, to send a follow me truck out to the runway because we can’t even see the edges.”
I left the VHF on and thanked GCA for the approach. The guys in the tower didn’t believe we were there. They had walked outside and couldn’t hear or see anything. We assured them that we were there, somewhere on the localiser centreline, with about half a mile showing on the DME.
Then I remembered the story from Fate Is the Hunter. When Gann was an airline copilot making a simple night range approach, his captain kept lighting matches in front of his eyes. It scarred and infuriated Gann. When they landed, the captain said that Gann was ready to upgrade to captain. If he could handle a night-range approach with all of that harassment, then he could handle anything.
At last I understood what true professionalism is.
Being a pilot isn’t all seat-of-the-pants flying and glory.
It’s self-discipline, practice, study, analysis and preparation. It’s precision.
If you can’t keep the gauges where you want them with everything free and easy, how can you keep them there when everything goes wrong?
PART II
Over 90% of today's tourists travel by air. Its so much faster that the time saved more than compensates for the extra cost. In truth, even that statement is not really true in today's modern conditions. The advent of no-frills low-fare airlines have made the cost of flying cheaper than by rail, road or sea.
That said, travelling by air has its own limitations. These are mostly weather related and, in the odd case, aircraft availability. Sometimes, it is a combination of the two, when your specific aircraft gets held up ay another airport because it has a snag that needs attention, or the prevailing weather does not permit flight.
Automation will soon make flying possible in what we pilots call zero/zero conditions. An official definition of zero/zero exists: "atmospheric conditions that reduce cloud ceiling and visibility to zero." Current Instrument Landing Systems-ILS- have become so advanced that today's airliners require a Runway visual range (RVR) of 46 metres. The ILS transmits two beams, the Localiser (LOC) along the runway centre line and the Glidepath, along the aircraft's descent path. Both are displayed on one instrument, and the pilot has only to keep them centred to come down safely.
Runway visual range (RVR), in aviation terms, is the distance over which a pilot of an aircraft on the centreline of the runway can see the runway surface markings delineating the runway or identifying its centre line. RVR is normally expressed in metres. In the US, which has to be different, it is expressed in feet. RVR is used as one of the main criteria for minima on instrument approaches.
Category III is subdivided into three sections:
Category III A – A precision instrument approach and landing with:
a) a decision height lower than 100 feet (30 m) above touchdown zone elevation, or no decision height (alert height); and
b) a runway visual range not less than 200 meters (660 ft).
Category III B – A precision instrument approach and landing with:
a) a decision height lower than 50 feet (15 m) above touchdown zone elevation, or no decision height (alert height); and
b) a runway visual range less than 200 meters (660 ft) but not less than 75 meters (246 ft). Autopilot is used until taxi-speed. In the United States, FAA criteria for CAT III B runway visual range allows readings as low as 150 ft (46 m).
Category III C – A precision instrument approach and landing with no decision height and no runway visual range limitations. This category is not yet in operation anywhere in the world, as it requires guidance to taxi in zero visibility as well. "Category III C" is not mentioned in EU-OPS. Category III B is currently the best available system.
The main reason for the delay in using Cat IIIC ILS is its prohibitive cost. It might be required for only 6-8 days in a year! So why spend so much?
Autolanding
The Airbus 380 and Boeing 777/787 passenger airliners and the Dassault Rafale fighter jet have zero/zero capability as well as an autolanding system. An auto landing process is achieved by an autopilot together with the ILS. As the name suggests, the ILS directs where the plane goes and the autopilot ensures that it does so. The auto landing procedure is executed automatically but the Captain may still have to intervene to check that the speed is as desired when the flaps are selected from 0 degrees to landing position.
At 50 feet, the autopilot flares the airplane, a term to describe how it would raise the nose slightly to prepare for a soft landing. The computer would call out aurally the heights every 10 feet and then at around 25 feet, the throttles are closed. At this point, the airplane should sit onto the runway gently and roll along the centreline until it comes to a complete stop by the auto brakes with the pilot aiding it further with reverse thrust. If the Captain is unable to see the taxiway because the visibility has further reduced, he may request a ‘Follow Me’ vehicle to guide the pilot to its parking bay.
THE FINAL BIT
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| The first landing of the Mirage 2000 on the Gwalior-Agra highway |
THE FINAL BIT
My story is about the Mirage 2000 fighter aircraft and flying in the early1990s. My Base Commander was a pedagogue who would not look outside the Rule Book. I was the Air Force Examiner on the Mirage 2000 aircraft and had devised holding patterns, one-in-ten approaches, ILS stacks, etc., things never heard by fighter pilots before. The book said I could fly in RVR of 1000 metres. One day, it so happened that my Base Commander's de jure boss at Command HQ, the Senior Air Staff Officer (SASO), an Air Marshal, had come down to visit the base and see how we conducted bad weather operations.
It was drizzling that morning and the weatherman said that we could soon expect zero/zero conditions. The Base Commander shrugged his shoulders and looked rather apologetically at the SASO. SASO looked at me and said, " Air Force Examiner.. ........ ....Chicken?" I replied in a twang with a hint of an accusation, " Its your published order, sir. Override it and we could go." "Done," he said.
For those who don't know, the Mirage 2000 is the easiest aircraft in the world to fly, but bloody demanding to operate in war, given its multiple capabilities. The Indian Air Force took cognisance of this fact and split the force into squadrons with specific roles. The best aid available on board was the autopilot which could do anything, well, almost. In fact, the very same autopilot is fitted on the Airbus 319 / 320s. I had devised and tested an autolanding system, which I practised in a two-seater by night from the rear seat. Landings from the rear seat at night were not easy-you needed practice to get the hang of it. This was a drawback in the aircraft, in that the rear cockpit had a camera screen that repeated what the front-seat pilot could see through the Head Up Display (HUD) in the front cockpit by filming the HUD. The camera display was far too bright to see anything at all and had to be switched off. You had to approach the runway by looking through the side panels and aligning yourself with the edge of the runway. When about 50 feet above ground, you could see the runway lights, so getting back to the centre-line was easy. I would intentionally fly head down approaches at night, asking the front seat pilot to take over controls if my approach seemed hairy.
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| CAS Air Chief Marshal PK Mehra felicitating me on crossing 1000 hours on type |
The Mirage 2000 is a tailless delta-wing aircraft and faced a problem common to all delta-wing aircraft; the nose of the aircraft had to be raised fairly high to generate the lift required to come in to land at reasonably low speeds. In fact, the Concorde also had this problem, solved ingeniously by deliberately drooping the nose so that the pilot could see what was ahead. In the Mirage 2000, you had to raise your seat fully and change the display on the HUD to what is called the approach mode, which had a landing-oriented but totally different set of symbols on display. Landing after these two actions then became as easy as in the daytime. Rain was a problem, because, even in a drizzle, forward visibility reduced to zero!
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| Base Cdr congratulating me on completing 1000 hours on the Mirage 2000 |
I got the SASO kitted up and into the rear seat quickly enough. As we taxied out, the fog came in and visibility reduced to 30 metres. I handed over controls to the SASO and asked him to taxy out. He coped well, because the taxy-tracks were 30 metres wide and he could see the centreline and the grass beyond the taxytrack edges. As we moved further away, visibility dropped to 10 metres and I had to take over controls again. ATC piped in with a warning that RVR was 20 metres and dropping. Without informing the SASO, I switched the ILS on and used the localiser to get onto the runway centreline. I asked the SASO if he would like to take off. He declined, saying,"I can't see anything." I insisted he take off, saying that the aircraft was on the centreline and would stay there for the 450 metres required for take off. In any case, I was there to assist or take over if anything went awry. He agreed and the take off was uneventful.
We climbed out of all clouding by 9,000 feet. SASO started to throw the aircraft around, enjoying himself. Later, I took him down to 1,000 feet above ground level in a flattish and safe sector and, whilst still in cloud, showed him the ground mapping and safety modes of the multimode radar. I showed him how to distinguish roads from rail tracks, how to assess heights of hill features, what rivers and bridges looked like, danger warnings, etc. He was more than impressed with the quality of the display and what all could be achieved. Soon it was time to get back. I took over controls and said, "See for yourself how this aircraft autolands, sir," adding sotto voce that it was time to have a relook at orders issued at higher levels of command and control without really knowing what was actually possible in the field.
I got in touch with our local radar and informed him we were doing an auto-ILS and requested back up. I started to slow the aircraft down from 450 to 200 knots, punched the required buttons, raised my seat, selected auto-ILS and changed the HUD to the landing mode. I then showed SASO my hands and said, "I won't touch controls unless required."The aircraft autonavigated to the holding point and as my speed dropped below 225 knots, the "lower undercarriage" command prompted me to lower the landing gear. The aircraft had climbed to the stack safety height of 2,600 feet above sea level by then and entered the holding pattern at 200 knots. Since we were the only aircraft in the air, we exited the stack on our first turnaround.
I informed ground radar of our exit, lowered the landing gear and, as we approached the ILS LOC beam, the aircraft turned and captured the localiser. As mandated, I called out LOC capture. I then reduced power to hit approach angle of attack(ά) of 13° and maintained it. Soon we were on glidepath and the aircraft automatically commenced descent. Radar called out,"You're on glidepath and centreline. RVR is now zero in light drizzle. Wind is calm. Recheck wheels down and locked. Acknowledge." The Mirage 2000 has a beep signal that is transmitted on three frequencies at one time, when a button is pressed, but only if the wheels are down and locked. This signal confirms to the ground controllers that the wheels are actually down and locked. Radar, in turn, acknowledged the signal and we were now on ATC frequency on our second radio set. All this while we were in cloud. ATC called us and said that all runway lights and the AVASI (Abridged Visual Slope Indicator) were on. We would never see them. I then put the aircraft's 2000 watt landing lights on.
I had selected Radio-altimeter visual warning to 20 feet. As the aircraft silently descended through clouds, radar kept telling us,"On glide, on centreline." My hands were visible to SASO, who said,"Can't see a sausage outside." "Look at the Head Down Display, sir," I added. It showed our height, speed and glideslope. At 350 feet on radalt, I disconnected ILS glideslope, its minima being 300 feet-not even a Cat I ILS. I kept the last used glidepath on the autopilot and retained auto-centreline control. We were aligned perfectly down the centreline. At 100 feet, radar said, "Approaching our minima, on advisory if requested." I responded, "Yes, please."
He continued,"On centreline, crossing threshold, height should be 30 feet." It was. As the radalt warning came at 20 feet, I throttled back to idle and allowed the aircraft to sink, allowing the ά to increase to 14°. Close to the ground, at 15 feet and less, the air compressed under the large delta wings of the Mirage 2000 tends to cushion its landing. Radar said, "Approaching touchdown." As we touched down smoothly, the autopilot disconnected by default. I just stayed on the ILS line and asked SASO,"Shall we do another one, sir?" He declined. I gently brought the aircraft to a halt and asked for the follow me jeep. My engine noise and flashing lights were picked up by the follow me jeep, and I kept my landing lights on. This was reflected by the orange stripes of the jeep and we followed him all the way home at a sedate 10 kph. On the long stretch back, SASO waxed eloquent, totally impressed with the aircraft (and the Indian Air Force Examiner?)
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