Sunday, May 22, 2011

A really cool flight - simulated instrument and finding myself

This is the story of my first simulated instrument flight and a little exercise in finding myself. All I knew about this flight before we took off was we would do some simulated instrument work, and I needed to have my sectional and AFD available.

Some Background

Some background... a Private Pilot License allows you to fly under Visual Flight Rules (VFR) which means, simply enough, you have to be able to see to fly. You can't fly in fog or clouds because you can't see to fly. You have probably noticed commercial flights don't have that issue, they under fly Instrument Flight Rules (IFR) which means they can fly "by instruments" instead of looking out the window. This is where ATC comes in... they see where all of the IFR planes are via radar and they ensure planes don't hit each other or solid objects.

There is the problem of "continued flight into instrument meteorological conditions (IMC)" that causes many pilot deaths. This is the most common cause of pilots flying into terrain, called "controlled flight into terrain" or CFIT. IMC = clouds, fog, dust storms, heavy mist, anything where you can't see a horizon to fly by. When you fly into IMC, your senses cannot reliably tell you up from down or left from right or if you are turning, descending or going up. Spatial Disorientation its called. This is what the NTSB believes killed Robert Kennedy years ago.

The FAA doesn't want pilots and passengers dying in IMC, pilots don't either! So to get your private pilot license you have to have 3 hours of "simulated instrument" training. In spite of the fact that it is illegal for you to fly in IMC without an instrument rating and filing a flight plan and being under ATC control. This means you spend three hours flying with special glasses or a hood so you can't see out of the airplane and all you can see is the instruments. FAA does this to give the average Private Pilot a snowballs chance of getting out of IMC if they end up in IMC and not dying (I think). My CFI says he does it to scare us enough that we never get into it in the first place!

My First Simulated Instrument Flight

Here's how it went, we took off, got a downwind departure, and then my CFI handed me the "foggles" and I put them on. Then all I had to fly with was the instruments... here's a pic of the instruments I'm talking about. The 6 instruments in the box in the picture are the ones you use to figure out if you are going up / down, left / right, what speed, what heading, what altitude, what ascent or descent rate.

Imagine making sure you are flying a plane first of all. Then you are flying straight and level and turning to different directions and ascending and descending all on the basis of what these things say. Well, it was easier than I thought it would be. I flew for a while just going whatever direction or altitude I was told. Then he had me close my eyes and he did weird things with the plane, turned it various directions, etc. I assume the intent of this maneuver was to make absolutely sure I had no idea of which direction we were going. Then he had me open my eyes again and keep flying in "simulated instrument" conditions. We did that for a bit over a half an hour. It felt like an hour!

Finding Myself

He finally asked me where I thought we were and I laughed and said, "Somewhere in the state of California, Northern California I'm sure." Then he has me take off the foggles, I'm flying over a low mountain range with a valley and another range in front of me. This is a google earth view of approximately what I was looking at when the foggles came off.

Then he says "Figure out where you are, find the nearest airport and land there. You can use all available information, except the GPS". (That's because the GPS on the plane has a NRST button you can hit which will give you the nearest airport instantly. Useful for emergencies!) So the to main resources I had were my eye balls, the instruments and navigational aids in the plane, and my sectional chart. Here's a picture of the chart showing the area I was looking at:

Do you know what I was looking at? I didn't either.

The first thing I did was reset the heading indicator (HI to Compass) to the magnetic compass. I knew I hadn't re-set the HI once since we took off and I knew the HI "drifts" more and more from the true magnetic direction you are headed the longer you fly. So I knew it would be inaccurate. I wasn't too surprised the HI was close to 180 degrees off. So I just reset it to the correct magnetic heading (almost exactly due South) and took that as my 2nd data point. I was headed South perpendicular to a low mountain range a valley and another greener mountain range.

The next thing I did was do a 360 degree turn to see what was around me. I noticed the mountain range to the south was greener than the mountain range to the north again. Also saw a road going through the range I was over. But nothing else terribly remarkable. So, I decided to continue on the current heading, South, to see what was in this valley area. Valley's tend to have towns, highways, and rural towns tend to have little airports, so that should give me some clue.

As I flew further into the valley I started to see a couple little towns and a highway going through the approximate center of the valley. I started to get an idea... in Northern California most mountains run mostly north/south, not as east/west appearing as the ones I was looking at. With one exception, as you go south of the Bay area, California's land mass swings east, so the coastal ranges take more of an east/west direction. Also, the mountains in front of me were greener than the ones behind me, typical of a coastal range. So I guessed I was facing what I call the Salinas valley (the valley that extends south of Salinas between the coastal range and the range with the Pinnacles National Park). I don't know what its official name is.

Here's a zoomed in picture of the sectional for the area I was looking at:

I continued to fly South and I saw a town that I thought was Greenfield. So I started to look up the highway for the prison and down the highway for King City (which has an airport). As I got closer to what I thought was Greenfield I realized that town had an airport right next to it (on the north side)! Ah Ha! I pointed to the airport and said, "There's an airport right there!" I turned the plane to the airport. I was planning to overfly it and see if it has its name painted on the taxiway (many do) or at least I could get the runway numbers which would validate it was the airport I thought it was. I was almost 100% sure I was headed straight at King City at that point.

But, my CFI wouldn't let me off the hook that easy. He admitted many airports have their names painted on them but he wanted me to figure out another way to know where I was for sure. So I used VORs to triangulate my position. Those are the pencil lines you see on the chart near King City. The spot where those lines crossed (above the numbers 821) is where I was on the chart. I needed to have some idea of where I was to use the VORs in order to choose two VORs that were close enough to me for me to receive their signals and triangulate. That's why knowing in general where I thought I was, my guess at the valley I was over and the airport I was looking at, helped me pick the right VORs.

Now Land

Position triangulated, airport identified, I was ready to figure out what the pattern was at this airport, how I should approach it, what its CTAF was, weather available, what runways to use, etc. All "on the fly". The sectional gives you some of the needed information, the Airport/Facilities Directory gives you the rest. In the case of King City, there is no weather available locally to tell you what the winds are (winds determine what runway to use). So I dialed up Salinas weather. Salinas is almost 30 miles away, which means its likely the winds at King City would not be the same as Salinas at all, however, it was what I had. Salinas winds indicated I should use runway 29.

I flew away from the airport and descended to pattern altitude... flew back towards the airport and saw a plane take off using runway 29. That made me feel better about using 29. I did my radio calls and approached and landed. The landing wasn't great at all, but it was a bit better than previous ones. Taxi off the runway... and clean up. Then all I had to do was figure out how to get back. :)

I drew another line from the Salinas VOR to King City airport, figured out what to dial the VOR to and took off. Back under the foggles I go for more simulated instrument time. We get back eventually and land at RHV.


As we debriefed after the flight it was apparent my CFI was pleased with the flight (except the landing). He had an interesting question for me. He asked how did I know we were south when I came out from under the foggles when we kept flying headings north and east. He thought I said we were south when I said we were headed south. Ahhh... that explained why the HI was so far off from the actual compass heading. When I had my eyes closed he reset the HI almost exactly opposite the actual heading. But that trick didn't work on me because I assumed the HI would not reflect reality already.

The other thing I though was amusing. It turns out, when he had me take off the foggles over that low mountain range, we were pointed almost directly at King City and its airport. Of course I couldn't see it from where we were. He's a devious one.

In the end ... I got 1.2 hours of simulated instrument time and I am finally approved to plan for my first solo cross country flight. And guess where I'll be going? King City. This time on purpose!

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