February 15, 1999 A O S

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by	Linda D. Pendleton

About the Author ... Linda D. Pendleton is Manager of Computer Graphics and Animation for King Schools. She is also the author of a book, Flying Jets, and scriptwriter for several of the training videotapes published by King Schools, including "Navigation from A to Z," "METAR/TAF Made Easy," and "Handling Emergencies." Linda is an ATP with Citation 500 and Learjet type ratings, and a CFI with airplane, instrument and multiengine ratings. In her 10,000+ hours of flight experience, she's flown US Mail, freight, corporate, charter, commuter, and served as an FAA-designated examiner for the Citation 500. King Schools

The instrument rating checkride was the next morning. I was ready. N8236N was washed and polished and oiled and fueled and I had the logbooks thoroughly analyzed. There were bookmarks (these were the olden days, kids, we didn't have sticky notes) to note the location of all required inspections and ADs. The static system and altimeter had been freshly inspected and proclaimed healthy and I had my nifty VOR accuracy test log with entries almost every three hours for the past several weeks. I had VOT tests, airborne tests, ground tests and tests of one VOR against the other. I could explain it all.

I had a stack of charts and flight logs. I had analyzed every possible destination within range of my Cherokee and could discuss all the possible approaches at all the airports. There wasn't a line or tick mark on the charts I couldn't expound upon. I had been watching the weather and knew all possible permutations — as well as anyone can think they know the weather — and was prepared to discuss deviations to alternates and vectors around weather systems.

I had my test reports tucked into my logbook, which was bookmarked to enable quick location of records of all required signposts along my road to my instrument ticket. My second-class medical and my newly minted temporary commercial pilot certificate were clipped to my carefully typed and properly endorsed application form — along with the check for the examiner's fee. (It cost $60 for an instrument rating checkride in those days.)

I was ready for whatever the morrow would bring. Except for AOS.

My instrument training had gone quite well. I had started with my instructor, John Goodpaster, a few days after I got my private certificate in July of 1974. (We took a brief hiatus from the instrument training in September and October to work on my commercial ticket. There was an FAR change effective November 1, 1974,  upping the requirements for commercial, and I chose to complete the ticket prior to that date. I got my commercial certificate October 28, 1974. Just in time.) My Cherokee — N8236N — had dual nav/comms, a glide slope and an ADF-what more could you want in an instrument platform-and since she was a 1969 model, she had the now-standard arrangement of the flight instruments.

We started out with the typical chore of getting me able to keep the shiny side up and pointy end forward "solely by reference to instruments." Doesn't sound like much when you read it on the page, but for one so fond of looking out airplane windows as I am, it was quite an undertaking. The hood we used was one of those big plastic bucket affairs which, I am convinced, was invented to see how long it could be worn before it snapped your neck. About an hour under the hood was all I could take, but we kept plugging away.

Unusual attitude recovery fit right into the curriculum. I would attempt to fly straight and level. John would declare it an unusual attitude and direct me to recover. No problem. (It was during this phase of my training that I discovered that I have absolutely no propensity towards motion sickness!) Finally I got to the point that I could maintain altitude, airspeed and heading — and sometimes more than one at a time.

We flew almost every day, and each day when we returned, John would sign my logbook. "Flight by reference to instruments — heading, altitude and airspeed. Straight and level flight. Recovery from unusual attitudes. AOS." (Actually, it read more like "flt/inst — hdg/alt/as, S&L, recov UA, AOS"). After a few lessons, I got used to John's abbreviations — and handwriting — and could decipher the entries.

Except for AOS.

John was a stern taskmaster and insisted that I approach each lesson fully prepared, so I read and studied and attempted to know — immediately — everything there was to be known about instrument flying. I bought every book I could find on the subject. (I'm a great believer in book lurnin' and an avid reader, so Sporty's has made a tidy little sum during my aviation career.) I hadn't come across AOS yet in my studying, but I was sure I would soon — or John would explain it to me during one of our lessons.

I began the daunting task of VOR orientation and tracking. John commented that I had mastered S-turns during my private and commercial training and there was no need to continue to practice them during my instrument training. Hmph! I called it bracketing and he called it S-turns. (I'll never forget my surprise the first time I saw a VOR from the ground. It seemed firmly rooted in place and I had always thought they kept them on the back of flatbed trucks. "Oh, oh! Here she comes Harry. Shift that damn thing about two miles south, and get a move on it. She's getting close. Oh, oh, Harry. She's turning. Hustle it back north, now.") I got to know the Chicago Heights VOR better than I ever wanted. I would have dreams in which I would hear, over and over again "dah dit dah dit-dah dah dit-dah. Chicago Heights ... Vortac. dah dit dah dit-dah dah dit-dah. Chicago Heights  ... Vortac. dah dit dah dit ..."

Finally, I mastered it. I could tune any station, center the needle, and, with complete certainty, determine whether we were airborne or not. John recorded the progress in my logbook. "VOR orn/trk, intrcpt/trk, CGT, JOT. AOS." There it was again. AOS. I had come to the point now where I was reluctant to ask John to explain AOS. I just knew that the answer was going include something about my lack of preparation and seriousness about the whole deal. John was gonna say "If you had read everything I suggested, you would know what AOS is. Study harder." I wasn't ready to admit defeat yet, so I redoubled my efforts.

Now, there's one thing the government is good for, and that's developing acronyms, and aviation certainly has received its share. Why, we even have an acronym for our collection of acronyms! (You don't think so? What about the AIM?) I looked through them all. AOA for angle of attack. ASOS — close but not invented yet. I kept looking. And the training went on.

John and I moved on to ADF orientation and tracking and what a challenge that became. I love ADF work now, and I'll be sorry to see it go in a few more years, but that was NOT the case in 1974! 36N had a fixed-card ADF, and it was on the far right side of the panel. Digital tuning had not become a reality yet and so station identification was even more important than today — and more frustrating. But those were not my chief difficulties with ADF. I had no problem finding where in space a station was, and I could even home to one with a high degree of reliability, but the skill of intercepting or tracking a predetermined bearing eluded me for quite some time. John began muttering about S-turns and descending spirals and some stuff I chose not to understand. But I finally got it.

And all was dutifully logged. "ADF tune/ID/orn/trk/intrcpt/trk. AOS." This thing was taking on a life of its own. I became more frantic to solve the mystery and more and more reluctant to ask John for an explanation. I could just hear his response: "What do you mean 'what's AOS?' You mean you don't know? If you'd done the reading and studying I told you was necessary, you'd know what AOS is! You've got to get serious about this." And so I continued to search.

Finally, in the first week of October things began to click. I could maintain airspeed, heading and altitude — all at the same time. John found it necessary to induce unusual attitudes for me to practice recoveries. It was time to begin practicing approaches. We'd conquered all the pieces, now it was just time to put them all together. I was also able to stand almost two hours under the plastic bucket before the pain became too severe to tolerate longer.

What a joy it was to slide down an ILS and find the runway right there in front of me where it had been advertised to be. I had a bit more trouble with non-precision approaches. For a few hours, the technique of maintaining the airspeed and descending at maximum rate seemed uncomfortable. I was much happier with a nice tidy ILS, but even NDB approaches soon became routine. Circling approaches were also — and still are — uncomfortable. There's just something about so much maneuvering close to the ground and in low viz that doesn't seem healthy to me. (I still accept a hefty crosswind before I'll consent to circle.)

We were coming down to the wire. Only the instrument cross-country remained. And an explanation for AOS.

The instrument cross-country was one of the most satisfying flights I've ever had. I was on top of it from the preflight to tie-down. It may take me longer than some to learn things, but once I've got it, by golly, I've got it. And I've got it good! We departed 3HO and picked up the clearance for the Purdue University Airport. That wonderful little Cherokee of mine hooked onto the airways and just tracked the centerline like she was born to fly VOR radials. The NDB approach was a non-event and we landed for a welcome cup of coffee. Back airborne, we headed for Indianapolis and an ILS to a missed approach at IND. On the way to the South Bend Airport (now called Michiana Regional) I felt like I was on top of the world. The flight was a thing of perfection. I had never before — or probably since — flown as precisely as I did on that magical flight. After a pit stop at SBN we were on our way home. John played ATC and gave me an ASR approach to Hobart and we touched down on runway 18 at Hobart Sky Ranch.

And there it was in my logbook. The final entry for my instrument training: 3HO-LAF-IND-SBN-3HO. NDB 10 LAF, ILS 22R IND, VOR 18 SBN.

And no AOS!!!

What made this flight different? Didn't AOS apply to cross-country flights? Did John just forget to log it? I had less than two days to find out. I was scheduled for my checkride on November 16. It was now late afternoon November 14. I rushed home to begin a final search through my references. When I got to my apartment, the day caught up with me and I collapsed in the couch in one exhausted heap. I rarely get tired while I'm flying — the adrenaline rush is too much — but I cave in in a hurry once the flight is over.

I spent all day on the 15th studying. By that evening I was frantic and I still hadn't found the definition for AOS. I was tempted to let it go, but I then I would hear the words of the examiner. "You don't know what AOS is? You come down here and waste my time asking for an instrument checkride and you don't know what AOS is? What kind of pilot are you? Take this pink slip home and come back when you've studied more." Which was worse — admitting my failure to John or taking my chances with the examiner? I decided to bite the bullet and call John. I just couldn't stand the thought of a pink slip after all my hard work.

I made the call. It seemed to ring forever before John answered. Then I lost my voice. My throat was so dry I couldn't talk. Just before John was ready to hang up, I croaked "It's me. I have a question. What's this AOS you logged on almost every flight?" And I braced myself.

"AOS?" He seemed confused, too. "Oh, yeah. AOS. Well that's for 'and other stuff' in case I forget to log something we did."

And other stuff. AND OTHER STUFF. I almost got an ulcer over AND OTHER STUFF?

But I guess I should have asked.