Thursday, August 20, 2009

Big Bear - Santa Paula / Cessna 152 (N709YL) / VFR

Since I practically have the Big Bear - Santa Paula route memorized, I figured I could risk an evening flight in the extremely Spartan Cessna 152. I survived, but I still messed it all up.

With no DME and only one VOR, navigation is a challenge in the evening. I started out at sundown, so I still had light at Big Bear. I made my take-off and took note of my anemic climb rate, but that wasn't a problem because I was over the lake, with plenty of room to gain altitude. Passing over the dam, I turned into the valley through which Bear Creek runs. It was misty and only marginally VFR, but I know the way out of the mountains, so I did okay. So far, so good.

I entered the valley below the mountains and had my one-and-only VOR set to the 258 radial inbound to Pomona (which is on V16). I had a terrible time stabilizing my altitude, even though I've done well in some previous flights; there must have been some turbulence or updrafts. I finally got that sorted out, and I held my course reasonably well, given that there was a substantial wind and I was drifting significantly.

Beyond Pomona I experienced my first period of confusion. I'm not used to the slow speed of the 152, and I seemed to be flying forever after crossing POM. I was sure that I had busted the Class B at some points. I set my VOR to the 275 radial inbound to VNY after POM, and for good measure, I set the ADF to El Monte. Everything checked out, but I still felt that I was too far west, and the thought of getting into trouble for wandering into the Bravo worried me. The needles didn't seem to move for a long time, even as I flew ever west. I told myself that the instruments don't lie, so if they say I'm clear of the Bravo, I'm clear of the Bravo—assuming I wasn't messing up in the way I was using them, of course, which was still an open question in my mind.

Finally, finally, the needles started to move. The ADF had been pointing resolutely west without any obvious motion for quite some time, but finally it started to turn. And the needle on the VOR finally started to ease its way towards the center. This was quite a relief since it proved that I really was still east of the Bravo and out of harm's way. It took ages for the needles to move far enough to where I was ready to turn onto V186, but they finally did. My speed was only about 85 KIAS, very modest compared even to, say, one of my Dakotas (140 KIAS) or even one of my 172s (120 KIAS).

I got myself centered on V186 and proceeded to VNY. But here again, I encountered the same problem I had with POM: How do I know how far I am from the VOR? The rate at which the needle moves is one indication, but it doesn't change much until you're practically on top of the VOR. When you lose the VOR, you know you're passing over it, although it might be a little late to make plans by then. It was frustrating.

My workaround was to find some NDBs and tune the ADF to locate them. I used El Monte while passing POM. On the way to VNY, I used Pacoima. By watching the changing angles on both the VOR and ADF, I could get a fair idea of where I was in relation to the VOR, roughly. This helped warn me of my pending overflight of VNY, so I could prepare for the next station (Fillmore). The switch to Fillmore went well.

I had started my flight at about 7500 feet, only about 1000 feet AGL. As soon as I cleared the mountains, I started a descent to 6500. I stayed there until I crossed VNY, then I started a 500-fpm descent as I continued on to Fillmore. I know from the chart that there's nothing above 3000 feet on the way to FIM, so I could descend 3500 feet on the way, and I need to descend because Santa Paula is practically at sea level. My plan was to fly to FIM, then outbound on the 267 radial for about 6 miles (roughly 5 minutes of flight), then turn to 220 to head to KSZP. But I started messing up on the way to FIM.

It was the same problem that confused me: How far was I from FIM? It was dark, so it was hard to see landmarks. No DME, of course … and this time, no friendly NDB to cross-check with. Again, it seemed to take forever to reach the VOR. I flew and flew, gradually descending, and starting wondering just what was going on. At about four miles from the VOR (although I didn't know my distance at the time), I foolishly thought that maybe I'd better turn. Like an idiot, I turned to 220, thinking I'd be heading to KSZP. In fact, I was still 10 nm southeast of KSZP.

I flew and flew, with increasing anxiety because nothing looked familiar. There were dark spots among the lights, which could be the airport (KSZP has no beacon or runway lights). There were bigger dark spots that were probably rising terrain. This didn't reassure me. I found something that looked like the airport, but as I approached it, I realized that wasn't it. I kept looking in all directions for something familiar, and finally I realized that I was lost.

I tried setting the VOR for the 250 radial out of FIM, which crosses the airport, but I couldn't seem to get on the radial (here again, it was the slow speed of the aircraft that tricked me into believing that I was doing something wrong—had I just flown longer, I would ended up on the radial).

After a while, I gave up on that radial, and groped back and forth a bit trying to see something that looked like an airport. Finally I did see a fairly large airport (too large to be Santa Paula), and realized that I was looking at Camarillo. So now I knew roughly where I was. I tuned the Ventura VOR, and headed for the 344 radial, which crossed Santa Paula. This time I tried to be patient, flying doggedly west, reasoning that I had to hit the radial sooner or later. Sure enough, I did. When I reached it I turned carefully north to 344.

There were hills in front of me that made it hard to determine if I was going in the right direction for a time, but I recalled that Santa Paula is just north of some hills. The chart said that some of them peaked at 2700, and I was somewhat below that, so I climbed to 3500 or so. The mountains were mostly dark silhouettes, but I could see city lights beyond, and I remembered that the spot ahead of me that remains stationary in my visual field is the spot towards which I'm flying, so I put some lights at that point to be sure I'd clear terrain. At one point, I could vaguely see trees below lit by my landing light, so I was only clearing terrain by a few hundred feet, but that was enough. After I got past the hill, I could see the two dark riverbeds that merged just southeast of KSZP, and I figured I was nearly home.

Sure enough, the closer I got, the more everything fell into place, and this time I was certain that I was approaching KSZP. I made a left base approach to the airport, kind of messy and crooked, but I landed very smoothly at very low speed. From there I parked on the ramp.

The lessons learned here were that I should not yield to speculation and not assume that I've messed up if nothing in the instruments indicates that I have. The slow speed of the aircraft made me worry, but the instruments always showed which way I was going, and so, for that matter, did the landmarks outside the window. In the future I'll try to be more patient in the 152, and more confident in my navigation, and not assume that I'm lost when I'm actually not (since assuming I'm lost may lead to me getting lost!).

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