I Learned About Flying From That

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It was on a short final into Palo Alto in a Grumman Tiger that things began to go weird.

I was a relatively new private pilot and it was my first flight in the Grumman; in fact, it was my checkout flight. For several months I had been making maintenance runs for my flying club in various single-engine Cessnas and Pipers, perhaps flying a 172 from the club's base in Palo Alto to the mechanic in Hayward for an annual, then running some engine parts in a freshly serviced 152 down to Reid Hillview south of San Jose, then heading home. It was a bit more purposeful than just hacking around, it was free, and it provided good practice navigating the Bay Area's complex airspace.

My instructor, who by this time had become a friend and flying mate, thought I should get checked out in a newly acquired Grumman Tiger so I could expand my maintenance flight role. That hardly took any convincing at all, and so off we went.

The glass canopy was a novelty, the wing looked too small to hold us up, and the handling seemed sprightly. The free-swiveling nosewheel took a little getting used to, but with some trial and error we ended up pointed the right way.

We flew from Palo Alto across the bay to Hayward and out to Livermore, doing airwork and touch-and-goes along the way. I focused on the higher approach and landing speeds and on keeping the nosewheel off the runway as long as possible.

Then it was back to San Carlos, where I made an uneventful full-stop landing and taxied back for takeoff. San Carlos airport lies less than 10 miles northwest of Palo Alto and is oriented in the same direction. When flying from one to the other, many pilots don't have time to pick up the ATIS and simply confess to the tower that they're "negative ATIS." This usually doesn't bother the receiving tower and it didn't this time; it is simply part of the busy local environment.

At Palo Alto our downwind was extended for traffic and the tower finally called our base near Moffett Field, a former naval air station and home to huge blimp hangars. This was almost routine and it left us set up on a long final approach. My instructor was a bit distracted; it was a clear though gusty day, I had been handling the airplane well, and perhaps she was tired. As every pilot knows, sometimes flying seems very pedestrian. But just because the tiger didn't bite you yesterday doesn't mean it's tame today.

As usual with an extended final, we stayed level at the beginning and kept the speed up, then slowed and started downhill.

Things soon seemed strange. I had a clear sensation that something was not adding up but the cues were too subtle to interpret, or even to be sure there was any signal at all in the noise. My inputs weren't getting the expected results, but I wasn't sure if it was me or the unfamiliar aircraft or something else.

"Feels like we're going a lot slower than 75," I said to my instructor.

She looked at the airspeed indicator, which showed 75 knots, and glanced outside. "Yes," she agreed with a shrug that said: Just one of those things.

It felt like we were almost hovering over the ponds and flats at the edge of San Francisco Bay. But perhaps the winds aloft were unusually strong. Meanwhile the bumpy air rocked the wings and I worked to stay on the extended centerline. Despite juggling power adjustments and the descent in this unfamiliar airplane, I had little trouble keeping the airspeed needle on approach speed. In retrospect that was a clue.

The runway grew and the wind noise outside the aircraft began to sound odd. It sounded like it was getting slow, like the change in tone and pitch you hear before the stall horn in a 172. But we'd been flying this airplane all day and the airspeed indicator said we were fine. I had just landed it at San Carlos less than 10 minutes before. I was faced with either adding power when we were already too fast on short final, or else stomaching the awkward feel of not adding power.

It felt wrong to add power. But it felt more wrong not to.

I added power. No change on the airspeed indicator. Another ignored clue but I was busy keeping on the centerline, keeping wings level and preparing to land. At least things sounded and felt better. Whatever dim alarm bell had been ringing in my head was muted.

Over the numbers I rounded out and started to flare. The stall horn chirped once and the airplane quit flying. Apparently that wing really was too small because we dropped three feet and landed hard on the mains. There were some startled words. As we rolled out the airspeed indicator said we were still flying at 70 knots. It said the same thing as we turned onto the taxiway. And it said the same thing when we stopped.

As was now obvious, the airspeed indicator had suddenly gone bad. It was working one moment, then it froze.

I trusted that gauge. I really trusted it because it has been working all day. During those few critical moments of final approach the possibility that it had gone belly up never entered my mind.

Had we been at 100 feet and stalled, we might have ended up in another section of this magazine, one with terse language about the NTSB's findings that the pilot failed to maintain control and sufficient altitude and airspeed. Like a modern technological Siren, that airspeed gauge tried to lure us to our doom. Ironically, it was the music of the slipstream that saved us. The landing was both hard and surprising but nothing was bruised or bent.

In retrospect I was too complacent, too trusting and not analytical enough. There were several cues that we were slow, and while I heeded those I did so without a full understanding of the situation. Some form of Pavlovian conditioning worked; the stimulus was the sound of being slow and the response was to add power. A better response would have been to realize what had happened to the airspeed indicator.

We are often taught to trust the instruments but it is equally important to be constantly aware that they can and do fail. The information was there -- in the power settings, angle of attack and even the sounds. Trust the instruments, but avoid blind faith in them.

To see more of Barry Ross' aviation art, go to barryrossart.com.