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"Really Below Minimums"


Seth

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After my last IMC approach last weekend (hand flown, no autopilot - rental aircraft, cielings 400 on an ILS with decision height of 200) I remembered my first real IMC approach and popped out with the runway right in front of me. Great feeling - a close number two to your first solo. It then reminded me of a story I had read in the past so I searched online and found it about a pilot who three times flew below minimums. I never intend to fly below minimums, but this is a good read:

Lionel Alford, Jr., "Military Aviation Adventures"

Really Below Minimums

by L. D. Alford

I do not intend to brag about the first two landings, but I will take full credit for the third. The first two were entirely unintentional while last one was accomplished with foresight and planning. This account does not include the many approaches I have accomplished at minimums to successful landings nor approaches that were made in spite of what others thought were below minimum conditions but really were not. These were approaches made under weather conditions no-kidding lower than theoretically possible to make a successful approach and landing.

OV-10AGrey.jpgThe first two were under similar circumstances and to the same airfield. They happened while I was flying in West Germany during the cold war. I was a Forward Air Controller (FAC) flying an OV-10. The OV-10 is an awesome FAC aircraft that was designed for Vietnam, but it could have been used anywhere around the world for its primary purpose—to get fighter and bomber ordinance on target. The OV-10 was also a great LARA/COIN aircraft—Lightly Armed Reconnaissance Aircraft/Counter Insurgency. It carried two UHF radios, two VHF radios, an FM military band radio, and a 400 Watt HF radio. While flying over the German countryside in the OV-10, you possessed more broadcast power than radio free Europe. The OV-10 had twin turboprop engines with the engines connected to booms that extended back to form the two vertical tails. The horizontal stabilizer stretched between the vertical tails. It was an outstanding aircraft as long as it was not overloaded or the temperature was not too high. In case of difficulties, it was a jettisonable aircraft with near zero/zero ejection seats.

OV-10AFormation.jpgBoth of my lower than documented instrument minimum approaches occurred at Alhorn Air Base, Germany. Alhorn was a forward operating location where the USAF kept fighters based alongside German aircraft to protect West Germany from Soviet Pac aggression. When we were visiting, the F-4s were being moved out and the A-10s moving in. The OV-10s were there to provide FAC work and coordination with the ground attack A-10s and the F-4s. In reality, we just flew up from Sembach Air Base, flew around for a few days, had a great time with the German Air Force Officers every night, and flew home.

The Germans really knew how to take care of their flying officers. They served breakfast in the squadron, provided fantastic wine, and had an O-Club with excellent food. If you needed it or not, they would give you a box lunch that included a small bottle of white wine. We really liked to visit Alhorn. Usually we deployed in groups, but many times, we went up as a single ship.

I was alone, unarmed, and unafraid the day I flew out of Alhorn on a four hour FAC mission into northern and central West Germany. I messed around in the low fly areas for a while, but the weather really was getting bad, and there wasn’t anyone else out in the airspace to play with. All the fighters were sitting on the ground. They had decided early that the weather was too bad to launch. They were right. My fragged landing time was 1600 local. The FRAG is the joint document that includes the directed Air Tasking Order (ATO) for the day. The ATO is what your flight times, loads, and missions are based on. So at around 1530, I picked up an IFR (Instrument Flight Rules) clearance from the local controller and headed back to Alhorn RTB (Return to Base).

Here’s what I learned about the West German base approach controllers. First, they are the best approach controllers in the world. Second, they get off at 1600 every day, and they are not willing to compromise those hours because of any aircraft flying anywhere. Alhorn did not have an ATIS (Automatic Terminal Information Service). An ATIS is a dedicated radio frequency you can dial up to get the current weather at the base. The only way to get the weather at that time was to ask approach. When I called up, the approach controller said the weather was 300 foot ceiling and one mile visibility and offered me the PAR (Precision Radar) approach. They weren’t grumpy about it, and the weather was bad enough, I was expecting the PAR. A PAR is a great approach that is hard to find now. In the United States, only the Navy keeps them up. They require a specially trained controller who watches your aircraft’s skinpaint on a special high performance radar and calls heading and glideslope information to you. They basically talk you down through the weather to landing. A PAR requires a well trained aviator and a well trained controller—these PAR controllers are the guys of legend: deep clear voice, practiced perfect cadence, quiet, calm, competent. That’s exactly the kind of controller I received going into Alhorn. I could hear the PAR final approach controller mentally crack his knuckles as I was passed to him. He again relayed the weather as 300 and one. His cool German accented voice came clearly over the radio. By the experience in his voice, he could have been one of the guys who called PAR approaches for the Luftwaffe in World War Two.

The approach went great. I was right on course and slightly below glideslope all the way. In Europe, the frequent terrible weather taught us to fly PAR approaches “slightly below” and ILS (Instrument Landing System) approaches half a dot below because that gave you a better chance of seeing the runway environment and landing in really bad conditions. The OV-10 is a fantastic instrument aircraft once you get used to it. Like all overblown prop wings, it can give you problems if you are ham fisted with the throttles, but I’m pretty good at instruments.

I was mesmerized by the controller. The way things work on a PAR approach is you just follow the controller’s directions. The controller tells you everything—including when to go around. You are supposed to watch the altimeter and back up the controller, but many PARs go down to 100 and one quarter of a mile visibility. You barely have any time to make a decision by yourself. I should have realized something was wrong when I arrived at 300 feet AGL on the altimeter, and I had no runway lights in sight. By that time, things are happening pretty fast, and the controller didn’t wave me off, so I continued down the approach. Although I was technically limited by TAC (Tactical Air Command) and USAFE (United States Air Forces Europe) regulations to 300 and one, the approach was legal down to 200 and one half. At minimums, 200 and one half, you are supposed to go around. The controller is supposed to declare minimums, and you go. The controller did not and I was starting to see something—I wasn’t sure what. Your altimeter can be up to 75 feet off and still be good for flight. The PAR track is 100 times better than that. I arrived at 100 feet and I was thinking hard about a missed approach, then I caught the white runway lights rushing by. I never saw the end lights or the sequenced flashers. I couldn’t read any distance markers, but I was just a hair below the glideslope and right on course. I landed between the lights and came to a halt.

I couldn’t see the next set of lights. I couldn’t taxi. When I was flying at 120 knots, the lights came by quickly enough that I could see them during flight, on the ground, they were spaced far enough apart that I was sitting between two and I could not see the next set ahead or behind. Theoretically, NATO standard lights are set at 60 meter increments, that’s about 200 feet apart. That meant I landed when the visibility was less than about 200 feet—total W0CS0F (Weather zero ceiling, surface zero feet). I didn’t do anything for a few minutes and tried to think of how I was going to safely taxi off the runway. The approach controllers knew I was down—they had already gone home. The tower called me, “What are your intentions, Antar 21?”

As calmly as possible, I asked, “Alhorn tower, Could you please send a trust-me truck to lead me off the runway? I can’t see to taxi.”

The Germans didn’t even laugh.

I learned that evening from the German officers that it is always a little bit of a problem coming in near 1600 because that is when the German controllers get off work. They don’t get paid for overtime, and they do not want to have to stick around while they coordinate your divert to another base. Therefore you get “Hans.” Hans was the approach supervisor and only came out of his office to do any control work in just these situations. Just like I thought, he supposedly talked down German aviators during the Second World War. He was a great PAR controller.

They fooled me again a week later. You would think I would have learned. I just was taken in by the audacity of the whole thing. They again called the weather at 300 and one. I believed it, and I received Hans again. That should have clued me in. The second approach went just like the first. By the book, I know I should have gone around, but I trusted Hans, and I liked the club at Alhorn. That was the second time I had to ask for a trust-me truck to lead me off an active runway. To my and the Germans’ credit, the weather was a little better this time. Chalk the whole episode to a young aviator’s inexperience colliding with a very experienced ground controller, and a lot of WOM (Word of Mouth) that you can only learn by experience. You know what? I’d do the same thing today—given the same quality of controller. When you risk your life with a trained PAR controller like that, the risk is the same whether you are at 300 or 100 feet. Now days we mostly just trust the instrument systems. They can’t make human errors by themselves, but they sure can kill you just as quickly—they just don’t experience any remorse.

The third time I had the opportunity to fly an approach below minimums it was done quite legally and intentionally. In the Air Force Materiel Command (AFMC) the same rules apply as they did to the Federal Aviation Administration (FAA). At the time, if the weather went below minimums and you were beyond the Final Approach Fix (FAF), you could continue the approach to minimums. If you picked up the runway environment and were able to land safely, you could land. These were not the rules the rest of the Air Force played by. In all the other Air Force commands, the moment the weather went below minimums, you were required to go missed approach and divert.

My good friend and test pilot buddy Jeff B. and I were taking the Sabrecross CT-39A out to Edwards AFB for some flight testing. I can’t tell you everything about the Sabrecross, but I can tell you that at the time, it was the most advanced EMCM (Electromagnetic Counter Measures) testbed in the world. It could do stuff that would rock your socks off. It was also the least aerodynamic T-39 in the world. One inch square Radar guides ran from wingtip pod antennas to the fuselage. A six inch wide by one inch high radar guide ran from the nosecone to the first passenger window on the copilot side. The aircraft was a pig. It could barely make half the range of a normal T-39 with a full tank of gas. Since the Air Force kept threatening to put it in the bone yard, we never upgraded the copilot’s instrument cluster.

T-39ACockpitanotated.jpg

Now, here is a beautiful thing that was lost when we put the Air Force T-39s in the bone yard. When I flew them, the T-39s had a T-38 instrument cluster on the pilot’s side. The T-38 instrument cluster is likely the best steam-gauge IFR (instrument flight rules) flight cluster ever designed. Steam-gauge means a non-electronic display. A great flight cluster is designed in a cross-T with a big Attitude indicator (ADI) at the top in the middle. An ADI tells you the pitch and roll position and rates of the aircraft and allows you to keep the dirty side down in weather. Below the ADI is a Horizontal Situation Indicator (HIS) that shows your corrected gyro magnetic heading—heading indicator. To the left of the ADI is the airspeed indicator and to the right the altimeter.

T-39BCockpitanotated.jpg

On our T-39Bs, the co-pilot instrument cluster was an updated T-37 set up. This was a cross-T with a small old ADI above a simple non-correcting gyro compass. At the left of the gyro compass was a Course Direction Indicator (CDI). In the T-37s we called the CDI the toilet bowl. When that’s all you have, that’s all you have—it sucks.

Unfortunately, our T-39As possessed the original T-39A copilot instrument cluster. The original T-39 instrument cluster was the same as the old T-37 instrument cluster which was similar to the original new USAF style World War II cluster. This instrument cluster was the best example of a badly designed instrument setup since the original World War II ones that killed so many aviators.

The original T-39A instrument setup had six instruments all of the same size in two rows. The top row included airspeed indicator, gyro compass, and ADI. The bottom row had an altimeter, CDI, and Vertical Velocity Indicator (VVI).

So we had three different instrument setups in our aircraft. The reason this was so great is that on the same day, I could take you out flying and let you experience three improving flight instrument clusters. When you flew the original T-39A copilot cluster, you would say—this sucks, but it was generally intuitive and pretty basic. It is the kind of display most aviators had to put up with until the early 1960s. When I put you in the T-39B copilot cluster, you would say—this is much better. It is a basic cross-T so it is very reasonable to fly. When I put you in front of the pilot’s instruments, you would say—now, this is really great. You’d never want to fly the other instrument setups ever again. From a test standpoint, when I let you fly any of the modern non-steam gauge e-displays most of them actually have a higher measured workload and are harder to fly than the T-38 standard display set.

What has this got to do with flying below minimums? Well, the Sabrecross CT-39A Jeff and I were flying had the great pilot instrument display and the terrible copilot instrument display. I was logging instructor time from the right copilot seat, and I was flying the leg. When you fly in a crewed aircraft with a pilot and a copilot, you take turns flying each leg. On each leg, one guy completes the pilot duties and the other guy completes the copilot duties. That’s the way it works. I was acting as the pilot for this leg. We were flying our first leg from Wright-Patterson AFB in Dayton, Ohio to Scott AFB, near St Louis, Missouri. That’s how bad this T-39 was; it could barely make 1.5 hours in the air, and I was flying with the worst instrument cluster left in the Air Force.

The weather at Scott was scoshe—that means it was really bad. It was near minimums all day with high cross winds, rain, and fog. We didn’t have many options because of our gas load and the gas-guzzler we were flying. When we descended into the airspace, I chose the ILS to runway 32L and there was still a 15 knot crosswind. The minimums were 200 foot ceiling and 2400 Runway Visual Range (RVR) (one half mile), and that was the reported weather. Technically, if you have the gas, you don’t have to worry about the ceiling and you can fly a visibility only (only visual weather requirements) approach. We had enough gas to complete an approach, missed approach, and go to our alternate, so we were good for vis only. As we hit the FAF, the controller called the weather below minimums at 100 and 1600 RVR (1/4 mile visibility) and asked, “Swift 61, what are your intentions?”

I nodded to Jeff, and Jeff told them, “We will continue our approach.”

“Sir, the field is below minimums.”

“We will continue the approach.”

I was flying on the poor instruments using a CDI sitting on the toilet bowl as we called it in Undergraduate Pilot Training (UPT). Jeff was watching everything carefully on his side and searching out the windshield for the runway. I used the techniques many years and many hours taught me. I flew one half a dot low, and put the course about a quarter dot to my side. That would let me see the runway and lights first. Jeff was making the radio and altitude calls. Right when he called minimums, I caught sight of the sequenced flashers on my side. I centered the aircraft and made a perfect landing. It was really beautiful. Jeff looked over and smiled—he thought it was a pretty slick approach.

The problems started after we shut down engines and entered base operations. I received a call from the base commander and the wing commander. Since this was Military Air Command (MAC) headquarters, I was surprised I didn’t get a call from CINCMAC. The base commander and the wing commander wanted to know how we landed when the field was below minimums. I had to explain to each of them about AFMC regulations.

The real problems continued when I had to call our Wing Operations Officer and ask him to give us a waiver to take off with the weather below takeoff minimums. Although MAC let its crews takeoff using dual alternates under these conditions, AFMC did not. We told our Wing Operations Officer what we were planning, and he approved the waiver right away. After we were refueled and had lunch, we took off uneventfully for our next destination out to Edwards.

So I really did land three times below instrument minimums and lived to tell about it. I suggest that if you ever get the opportunity, unless you are trained, very experienced, have a great crew, and follow all the rules, don’t even think about it. I was lucky as a young aviator to have the help of a fantastic ground controller. Admittedly, a controller that was more interested in going home than my safety, but remember, if I had a difficulty that would have really delayed his time off. In the other case, I had a test pilot on my left, and I am a test pilot. We followed the rules to the tea, and we knew what we were doing. Except in an emergency, even contemplating an approach when the weather is below minimums can lead you to a very risky situation. My advice—forget about it.

- The End -

The author is a retired Air Force test pilot. His other aviation, technical, and fiction writing can be referenced at www.ldalford.com.

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What a great story! Not one I would care to try myself, especially considering the assistance I received on my last surveillance approach . . . Thankfully it was a practice run for the controller and not something I needed. I'll be looking for the author's website.

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