Friday, May 29, 2009

A Superior Aviator...

...uses superior judgment to avoid situations requiring superior skills.


Oops.

One of my students wanted a little more cross-country practice before setting out on his own. He's done well on his dual cross-countries, but confidence is confidence, so I was happy to help.

I decided to take him out to visit a couple of the strips in the Idaho desert. "Let's go to Midway," I said, "and then the airport closest to Midway." I made it into a scavenger hunt. Predictably, he chose Arco as the nearest airport; the open circle at Big Southern Butte doesn't really look like an airport, does it?

The state Department of Aeronautics' web site shows conditions at back-country strips. "Rough," it said of Midway, but "Good" at Big Southern. So our plan was to do a low pass at Midway, then land on Big Southern, then head home.

It was a beautiful calm evening, and we sped across the desert to Midway. We circled it a couple of times in disbelief, then headed over to Big Southern by pilotage.

"Let me show you how to drag the field," I said. That means to fly just over the runway, off to one side, so you can see if it's in good enough condition to land. If it was, we'd go back and touch down. I was looking forward to the loud sound of wheels on gravel.


I set up downwind, base, and final, nailing the speed for a short field landing. Our aim point was the numbers.

"But there aren't any numbers!" he protested.

"We'll aim for where the numbers would be."

We saw right away that we wouldn't land. There were tire tracks in the gravel, and the surface looked soft. I added a little power and moved off to the right edge.

"Why are you on the right?" he asked.

"So you can look at the runway. But watch out for the wind sock." I distinctly remember looking up at the wind sock.

The stall warning chirped. I looked over at the airspeed, and was surprised to see the needle at 2 o'clock rather than at 3. Gulp.

I gave it full throttle, took off the carburetor heat, lowered the nose, and raised the flaps just this much. We got 5 more knots. We got 8 more knots. I raised the flaps just a little more. We crossed the fence at the far end, where I finally looked ahead. Everything in front of us was higher than we were.

But we had flying speed. I raised the flaps just a little at a time. We started to climb.

"You have the flight controls," I said, "but be gentle." He turned a little toward the mountain, but straightened out and we headed for home.



So where was the accident chain broken?

Nowhere. The accident chain was never broken!

No, we didn't have an accident, but I did have to use serious stick-and-rudder skills to prevent the accident from happening. Too many pilots have stalled in this situation; low-level maneuvering is one of the big accident causes.

This accident sneaks up on pilots. But we can't ask them, since the accident is usually fatal, so we have some guesses.

Here's one: sightseeing in a twin, 1,000 hours in type, it's VFR, what could go wrong? You slow up to tighten the turn, and stall. You have an aft CG, so the elevator is less effective in the (failed) stall recovery. Or you fly through final in a PC-12, pull back to tighten the turn, and stall. Or you're at circling minimums in a King Air, losing sight of the airfield, so you tighten the turn a little, and stall. The Champ isn't climbing in the thin summer air. You raise the nose to clear the trees, and stall. The glider won't make it to the runway, so you try to stretch the glide, and stall.

As an old friend put it, "Stall - Spin - Crash - Burn - Die."

Don't.

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Thursday, May 28, 2009

Walking (not running) the Ridge


Ridge running is one of the joys of glider flying. Air moving perpendicular to a ridge line has to go somewhere, and the only place to go is up. When the ridge is working you can fly for hours. And that means fly. Flying something like a King Air is to ridge running what riding a glass elevator is to rock climbing.

But there's more to life than flying. Really.

That's why the kids and I went hiking on Monday (Memorial Day holiday in the USA). We have it good: to go hiking we put the dog on a leash, walk out the front door, and turn left.

It's a steep hill, and the sun was hot, and there was no wind. I was more concerned about water than anything else; no point in getting dehydrated.

We climbed until the slope leveled. The trail was a fire break along the ridge line, cut about 20 years ago during a devastating fire on the other side of the ravine. The trees have not grown back. It's wide enough to land on, and the slope is shallow enough, too, if it weren't for the knee high boulders.

We climbed about 1000 feet to the National Forest boundary, a logical place to stop. We admired the view and started down. I had a lot on my mind, a lot of good stuff: watching the kids, watching the dog, watching my step, the good feeling of exercise, and admiring the view. But there's always one corner of my mind that stays in the air. The breeze was light, first from the left, then the right, then ahead, then from the left. "Not a good day for ridge soaring," I thought.


But things changed in a hurry. Without warning, the wind was at our backs, tumbling down the slope at 25 knots or so. My son turned to say something, but I couldn't hear him. I held onto my hat. I thought about cutting toward the trees.

I looked back up the slope. The little finger of cumulus that had been hanging above us in the first picture, just a few minutes before, had blossomed into the massive CB in the second. Ouch!

It ended as quickly as it began.

I'll remember this storm the next time I'm ridge running. It's true that walking the ridge can make you better at running it.

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Saturday, May 23, 2009

Mapping Things Out


All pilots are interested in maps. Well, no, but all pilots should be interested in maps. Well, maybe no, but I am fascinated by maps.

Over Spring Break we stopped at the museum at the first capital of Utah, in Fillmore. The old capital building houses a nice museum; we learned a lot about the European settlement of the Great Basin. There is a small National Guard armory next to the museum, where a friendly Guardsman gave my daughter and I an in-depth tour of a Paladin howitzer; she even got to position the gun.

The gift shop had a nice book collection. I picked up Mapping and Imagination in the Great Basin: A Cartographic History, by Richard Francaviglia. Francaviglia details the development of mapping in the Great Basin, which is roughly defined by the states of Nevada and Utah. "Hmm, one of those books that only I would like," I said.

Well, I was right, at least about me liking it. It followed me on recent trips to Boston (on United) and Truckee (in the Cherokee Six). My flights to and from Truckee took me on a diagonal cut across the whole Great Basin. Francaviglia describes the mapping of Virginia City, the Great Salt Lake Desert, various mountain ranges, Pyramid Lake and Lake Tahoe, and the course of the Humboldt River (which I had generally followed). I had just flown over most of it, at fairly low altitude, so my mental pictures were recent and vivid.

Plus, I had been studying the Salt Lake, Klamath Falls, and San Francisco sectional charts, with their effectively infinite amount of information. Francaviglia shows how depictions of terrain have changed over the years. I (indirectly) learned a lot about the imagery on sectional charts.

I have done a fair amount of flying in the Great Basin, including a week based in Winnemucca fighting monstrous wildfires, several trips to Battle Mountain, and glider flying in Minden, NV. And there was the epic two-day (each way) journey to Watsonville, California in my 65 horsepower Taylorcraft. (I followed the same truck from Wells to Winnemucca.)

Explorers came successively on foot, by horse, by wagon, by railroad, by automobile, and finally by air. This does not include our ilk: nobody following a victor airway can possibly be an explorer. But, as Francaviglia points out, the social context of maps includes more than exploration.

The last chapter is about the period 1950 - 2000, and includes some fascinating examples of airline route maps. United's map showing the route from Salt Lake to San Francisco was best. Why? It included navaids! In those days, the navaids were four-course ranges, and the route was the west leg of the Salt Lake range (which was notoriously unreliable), then a heading to pass north of Wendover and intercept the east leg of the Elko range, crossing Battle Mountain and Fallon before crossing Reno, intercepting the northeast leg of the Sacramento range, then to Oakland and, finally San Francisco, roughly following V32, V200, and V6.

Remarkably, the map even shows navaids that are not part of the route.

And this has led to a revelation about airlines and their attitude about passengers:

  • Which airline gave passengers a route map including navaids? United.

  • Which airline lets passengers listen to ATC on the in-flight entertainment system? United.

  • Which airline, pre-9/11, had the most generous jumpseat policy? United.


  • On United, the passenger is a crew member! The only other airline that comes close to this is Southwest, although in a different way. Southwest pilots seem to be more in love with aviation than pilots from other airlines, and more than once a Southwest pilot, seeing the "Crew" tags on my luggage, has come over to strike up a flying conversation.



    I used to carry charts when I flew as a passenger. But now this might seem like suspicious behavior, so I make myself leave them behind, at least for familiar routes. A couple of years ago, riding in a 737 from Bangkok to Krabi, though, I couldn't resist, and my daughter and I noted the cites and airports as we flew by.

    If nothing else, it keeps you ahead of the airplane.

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    Wet and not Wild


    Here's a picture to ruin a glider pilot's weekend. It's instructive (and, at least for me, fun) to see why.

    Ridge soaring in northern Utah depends on a west wind, but those bands of cirrus are coming from the east. According to the Rapid Update Cycle model sounding, the wind at the top of the ridge will be out of the northeast at about 10 knots. There will be no ridge soaring this weekend. Worse, the airport will be on the back side of the ridge, so a glider trying to get back from the ridge will be flying in sinking air. Yucko.

    The east wind is too weak to produce wave lift.

    The high cirrus means that the ground won't heat up enough to generate thermals.



    My soaring season began last week with four flights in the club Blanik. First came a tow to about 1700' above ground level, where I did some turns and stalls before entering the traffic pattern to land. No surprises. There was a little lift, which was encouraging, and while the surface wind was from the northwest and a little gusty, the wind above the airport was from the west.

    Then came two quick patterns. I concentrated on pattern emergencies, which would mean either rope breaks or tow plane problems.

    Now I was legal to carry passengers, so I moved into the back seat while a prospective club member got into the front. We took a high tow up to the ridge. The ridge was working weakly, and we flew the ridge for almost an hour. Then, as is often the case, all of a sudden there was no ridge lift to be found. The day had died.

    We still had plenty of altitude, so we fooled around over the city, looking for sources of thermals from Wal-Mart (big heat generator) to the university (lots of hot air there) to the skating rink (which often generates a thermal, for no reason that we can discern). We had some periods of zero sink, but nothing worth circling in. There was one weak thermal right over the airport. We were down to around 900 feet, a little low for trying to circle in it; I tried it because any sink we found would only make us use a different runway. But there wasn't enough lift, so we landed.

    We had flown more than an hour in weak conditions. I think it was a good introduction to soaring.



    But not today. Today there is a cabinet door hinge to replace, a sticky door knob to look at, and dinner to cook. Cirrus clouds above may kill the soaring, but things bode well for something on the grill.

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    Monday, May 18, 2009

    I shouldn't have...

    ...but I did.

    Back in January I whined that my wanderlust was unsatisfied. I am logging lots of time, and having lots of fun doing it, but I wanted to go somewhere. I made a day trip in March, but now it was May and my friend in California said that the fishing was good. School was out. I'd been bringing lunch to work, so I had a little money. It was time to go flying!

    Our club's airplanes are IFR but not modern IFR (see this post, but it's an axiom of aviation that if you pick a day to fly VFR too far ahead the weather will turn on you. In this case, the weather turned near the Idaho-Nevada line; I was down to 7200, and the terrain ahead was at 7500, always a bad plan! I turned tail to Twin Falls where I landed, ran inside, and filed IFR. (My apologies to the student pilot who watched me do this; I hate to let a teaching opportunity pass, and he was curious to learn more, but my friends were waiting for me at the airport in California.)

    I walked out to the airplane and taxied out.

    "60N, I see you filed the SNAKO departure, would you rather turn directly to the airway?"

    Gulp. "Um, yeah, I was in too much of a hurry to check the crossing restriction. What is it?" The departure goes straight out for 10 miles over low terrain, then follows a DME arc. It basically adds 10 miles to the flight. But, being lazy, I chose the safe route. This was silly: I had just flown over the area with a sectional open on my lap, and knew that I could outclimb the terrain.

    He removed the DP from my clearance and I just turned down V293.

    The MEA is 12,000 and the bases were around 11,000; I spent the morning bashing in and out of the clouds. The temperature was right at 0C, so there was a chance of icing, but I was using the "reasonable and prudent pilot" interpretation. Since the bases were high and it was warm at the surface, the probability of a dangerous icing encounter was negligible: if the ice got bad I would find a hole, cancel IFR, and descend to warmer air.

    There was a little ice. By the Aeronautical Information Manual, it was somewhere between a "trace" and "light;" there was no hazard.

    But the flight was quite easy. I hunkered down and watched the gauges. The key to smooth instrument flying is practice, practice, practice. I got 1.9 hours of actual IFR time.

    Nevada is pretty empty, and the only time Center called traffic to me was east of Reno. "I'm IMC," I replied, when he told me of opposite direction traffic 1,000 feet above. I tried to look up into the clouds, but that was pointless. Then "Mooney XXX has the traffic in sight."

    "That's a good trick," I said on the air, "since I'm in the clouds." Was my tail sticking up like a shark fin?

    "TCAS," he said. Whatever.



    With nobody to talk with, I critiqued myself. One thing I noticed is that it takes a lot of concentration to keep the pitch corrections small. My students, and I, tend to jam the nose right back to where it should be after a bump, but a slow, delicate slide works better. But being delicate is doubly difficult in the clouds or under the hood, so I am going to try having my students learn this maneuver by watching the horizon. It's amazing how slowly you can move the nose up and down, and slowly is the right way.

    Except when you hit the mountain wave and start sinking at 10 knots (1000fpm)! But that's another post.

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    Wednesday, May 13, 2009

    The Real Apache


    Which is the real Apache, Piper's or the Army's?

    Monday, May 11, 2009

    Lost Communuxqruba

    I promised to pass along some lost communications stories. I might have written nothing, shut down the blog, and called it an object lesson, but I have lost my taste for sarcasm and excessive irony. So let me communicate about not communicating.



    I had just gotten my instrument rating. I was trying to listen to local IFR traffic on a scanner, but all I heard was someone giving instrument instruction to a student. This guy was good; he was patient with the student, and used memorable phrases. "Missed approach!" I heard, "Pitch, power, trim." I learned a lot from listening to him coach his student. "Missed approach!" I say, "Pitch, power, trim." Just like him.

    The problem is that I was not his student. I was driving around in my car, and he had a stuck microphone, and nobody else could use the frequency. In other words, he was lost comm (or NORDO, as the controllers say), and so was everyone else on the frequency. It was an approach control frequency for a Bradley (Hartford-Springfield), a busy Class C airport, during the rush.




    I was a student on the downwind at Carlsbad-Palomar, a busy Class D airport. No answer from tower. No answer from tower. No answer from tower. "Better call them on ground," my instructor said.

    Years later, I was on the downwind to Boise, another busy Class C airport. It was VFR. Airplanes are checking in with the tower, but the tower had become the Roach Motel ("Roaches check in, but never check out."). So I called ground, "Boise Ground, 00X, tower's not answering, we're on the left downwind for 28L." "Clear to land," they replied, "Somebody turned off the transmitter."



    It was IFR and I was going into Olympia, Washington. Radar vectors for the ILS. Downwind, then base, then

    "Approach, Skylane 1234X, I departed from Klamath Falls about two hours ago, VFR, on top, red with white and yellow trim, my wife's on board, and, um, we're squawking 1200, 4 thousand 500, going to Bremerton, and, um..." He went on and on and on and on. Guess what? That makes me "lost comm." No equipment has failed, except for the space between someone's headsets, but lost comm is lost comm.

    I'm getting close to the localizer, wondering whether I should turn in, when the guy finally let go of the button. "Seneca 4BR, this is a vector through the localizer, turn left heading ... ." The controller got it all out quickly.

    This is an incredible dangerous situation. If you are on base for the ILS to runway 17 at Salt Lake City and some confused VFR pilot ties up the frequency like this, it could kill you: you only have a couple of miles to sort it out and you are already below the mountains.




    You do check the volume on the receiver every time you change frequencies, right?



    Departing London, Ontario (CYXU) eastbound, tower says "Clear for takeoff, contact Cleveland Center on xxx.yy when airborne." Shoot, I was at 3,000 MSL in an Archer, there was no way my little GA transmitter could hit Cleveland Center all the way across Lake Erie.

    Then things got spooky. I flew over an airport than wasn't on my charts (it was Aylmer, an abandoned RCAF field). A DC-3 flew directly over me, 1,000' above, heading in the opposite direction. I started to feel a little, well, panicky. So I did the right thing, and called London Tower.

    "Oh, right, you're still a little far away, try him again in 10 minutes."

    This used to annoy me going into Jackson Hole, Wyoming. Salt Lake Center would hand me off to the next sector before I could hit their transmitter, which seems to be deep in some valley. There was no problem as far as traffic, but a few times I flew by the IAF for the approach I wanted while waiting for them to answer, which meant a big turn. I tried asking for the approach from the previous sector, but they would never give it to me. Luckily, I usually flew this route empty, so the passengers didn't think I got lost.



    Faster airplanes sometimes get out of transmitter range before the controller can hand them off. Usually they'll call another aircraft from the same company and ask for a relay. "American 123, can you call American 456 on Guard (121.5) and tell him to contact Denver on ... ?" Just as often, you'll hear "Any aircraft on Guard, United 789, can you find out what frequency they want us on?"



    These stories might sound a little scary to the uninitiated, but they're not. The lost comm rules mean that everyone knows what do, and the risk of a collision or even a so-called "near miss" is very, very low.

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    Wednesday, May 6, 2009

    A Lost CRAFT

    I think most instrument pilots know about CRAFT: it's the acronym for the order of the elements of an IFR clearance:

  • Clearance limit;
  • Route;
  • Altitude;
  • Frequency;
  • Transponder code.

    My IFR Ground School has reached the point where we are starting to try to understand Air Traffic Control (ATC). Where do you begin understanding such a complicated system? I have always taught that the answer to every IFR puzzle begins "Well, in the event of lost communications, ..." That's where we began.

    The lost comm rules (14CFR91.185) have puzzled pilots for years. Most of it is logical: if you fly into a big hole in the clouds, continue under VFR, and land as soon as practicable. Call Flight Service and tell them what happened, and continue on your way VFR. You don't even have to shut down.

    You fly the highest (i.e. safest) of the minimum IFR altitude, the altitude you were cleared to, and the altitude you were told to expect. Still pretty simple.

    You fly the route you were cleared, or told to expect, or what you filed. OK.

    But when do you start down? The rule is complex, and I have heard a lot of silly interpretations over the year, some of them from my mouth, I am ashamed to say. "Just land and get out of their way" is the most common one. But what do the rules really say? And are they that hard to interpret?

    Yes, they are that hard to interpret. The difficult time is when ATC clears you to someplace other than the airport. They may or may not give you an Expect Further Clearance (EFC) time. You do different things in each case. Let's look at an example and see what the rules say.

    Let's fly from Provo, Utah (KPVU) to Idaho Falls, Idaho (KIDA). Checking skyvector.com shows that V21 goes from Fairfield VOR (FFU) to Idaho Falls VOR (IDA). The Departure Procedure takes you to FFU, so you file "FFU V21 IDA."

    This route crosses the Salt Lake City Class B airspace, and a typical clearance is "Cleared to the Fairfield VOR via the Provo Three Departure, Squawk 4321." The altitude and Departure Control frequency are on the chart, so ATC leaves them out. The chart also says "...Expect clearance for filed route and altitude within 10 minutes after departure."

    So far, the clearance limit is FFU, which is not an Initial Approach Fix for KIDA. The regulation is clear: your clearance limit is not an initial approach fix, and you do have an Expect Further Clearance (EFC) time. Start a timer when you're cleared for takeoff. If there is a communications problem, fly the departure procedure, hold at Fairfield until 10 minutes have passed, and proceed on your way. What has happened here is that ATC has given themselves 10 minutes to clear a path for you if something goes wrong. It's about 19 miles from KPVU to FFU via the Departure Procedure, so your 10 minutes will probably be up when you get to FFU.

    If nothing goes wrong, as you get close to Fairfield you hear something like "Cleared to the Idaho Falls airport via fly heading 330 to intercept V21, then as filed, climb and maintain 11,000." The heading is a radar vector, so if you lose communications you know to fly toward V21.

    Is this in the a gray area? The clearance limit, that is, the airport, is not an Initial Approach Fix. But since the airport is not an IAF, and you don't have an EFC time, if you lose radio contact you go to an IAF, then start the approach at your ETA. There should be an IAF in your flight plan route.

    Approaching Idaho Falls, you hear "Proceed direct Idaho Falls VOR, expect ILS approach." The clearance limit is an IAF and but you have no EFC time, so if you lose communications before Idaho Falls then you hold there until your ETA. You are given a route to "expect," too, so that's the route to fly.

    If it's busy, they'll spin you. "Hold South of the Idaho Falls VOR as published, maintain 11,000, expect further clearance at ... ." Now your clearance limit is an IAP, and you have an EFC. If the radios go bad, you leave IDA at the EFC and fly the approach.

    That's not so bad, is it? Of course it is. Not. But one way to learn is to imagine a few scenarios of your own. What if the destination is your favorite Class B airport? What happens if the destination is shut down by weather (I once had to divert from Laramie because the VOR had been hit by lightning, and all they had was a VOR approach. I didn't want to go there, anyway.) Playing "What if..." is a great way to sort this stuff out.

    Just remember to begin your answer with "Well, in the event of lost communications... ."




    Next: Unusual lost comm scenarios.

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  • Friday, May 1, 2009

    Will We All Get Sick?

    This is not about swine flu, or even type A(H1N1) flu. It's about airplanes.

    I love navigation, every aspect of it. I have taught courses, I have done research, I even wrote a book about it. Navigation strikes the perfect balance between action and contemplation. I like to think that I have explored every corner of the subject, but this week I learned something new.

    One of my instrument students is working on adding to his cross-country time. He needed to pick up a friend at an airport a couple of hundred miles away. I helped him with some flight planning, but the morning of the trip the weather was less than perfect VFR. Of course I would be happy to come along, I said. We spent some time going over my interpretation of the weather; it was important for him to understand why I thought it was safe.

    My motives were a little less than pure. I am thinking about upgrading my handheld GPS, and he owns one of the ones I am considering. I figured that it was a good chance to play with the unit in anger.

    The trip out was rough. There were scattered snow showers. Some were light enough to fly through, but some were not, and we had to divert a few times.

    But the turbulence was worse than the snow. "Continuous light and occasional moderate, and I mean continuous, every inch of the way," was how I put it to Flight Watch. (For those of you overseas, Flight Watch is actually Enroute Weather Advisory Service; and an inch is about 2.54cm.)

    "He's gonna get sick," was how my student put it, referring to his friend.

    And he was right. The climbout was rough, and it stayed rough, just a little smoother than before. I went on playing with the GPS and pointing things out on the charts, both IFR and VFR, and keeping a flight log, and playing with the camera on my iPhone. I even took out my circular E6-B and figured a new ETA when the headwind proved a little stronger than anticipated. I dug out the printed weather briefing and pointed out that the winds aloft were forecast to decrease as we got closer to home. It was a fine afternoon for flying, and for satisfying someone's curiosity about how to do longer cross-countries in more conditions.

    But it got quiet in back. Pretty soon I heard the headsets fumble in the intercom, and then I heard the sound of a bag in use.

    I pointed an air vent to keep the smell away and went on with my business. My student wanted to try something on the GPS, but was having trouble holding heading and altitude while he was distracted. I offered to take the flight controls. I like to think I fly smoothly, even when it's rough.

    "Oops, that was a mistake," he said.

    "Do you want the controls back?"

    "Oh, yes, please." Being at the controls helps keep the stomach under control.

    So while he stared out the window I did all the navigating. I thought I was fine, but let's just say that after we landed I didn't feel like eating for a while.




    The big lesson was about the physiology of being a navigator. Navigating is pretty easy these days; we don't follow in the footsteps of navigator Riiser-Larsen on Amundsen's expedition to the North Pole in the airship Norge (that's a hard 'g', by the way). Unable to take a sextant sight from the control car, Riiser-Larsen climbed to to the top and took the sextant sight in -40 degree air at 60 knots indicated. Ouch! And we don't have to do the calculations anymore. Most people find that a real advantage.

    But think about the poor navigator in, say, a DC-3 or DC-4 or even B-52. He's the second most nerdy guy on the crew (the radio operator being the nerdiest). He sits and does his calculations at a chart table, far from center of gravity. When it's rough, he really gets tossed around. But he doesn't get sick! (We'll omit the part about enjoying the trigonometry calculations; we all know pilots don't go for that.)

    Lots of pilots get sick. Gordon Baxter wrote about it in his columns for Flying. Many glider pilots spend their first flight or two of the season in absolute agony, returning with filled gallon zipper-lock bags.

    One afternoon, two of use were headed home empty in a Cessna 414. We were both coming up on recurrent training, and I, as the instructor, got the bright idea that we should dig out the POH and quiz each other on the airplane systems. After a couple of minutes of reading questions to me, Al closed the book and said "That's it." He stared straight ahead. I gave the controls to him and read about systems until it was time to start down.

    So, let's all have a little respect for the navigator. He's the nerdy guy with the iron stomach. Aviation would never have gotten anywhere without him.

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