Density-Altitude Debacle Leads To Near Disaster

Departing a high-elevation airport in warm weather strains the capabilities of a Grumman Tiger

plane flying over cows illustration
A near-disaster in the desert.Barry Ross

Back when I was a fledgling aviator with less than a thousand hours in my logbook, I ferried airplanes for various aircraft brokers throughout the United States to build time. My goal was to gain 1,200 hours of flight time so that I could hopefully become employed flying canceled checks with a Part 135 operation. The brokers would buy an airplane and call me to reposition it to their home hangar. They liked using me because at the time I worked for a major airline with flight benefits and this saved them a good deal of money.

This particular trip would start out in Palo Alto, California, with my final destination being Dayton, Ohio. Early that morning I took an airline flight from my home in Orlando, Florida, to San Francisco and continued by ground transport to Palo Alto Airport (PAO) where I was to ferry a Grumman Tiger AA-5B. This was my first flight in a Tiger and I was looking forward to flying this little pocket rocket across America.

In my humble opinion, the Grumman Tiger is one of the finest light single-engine aircraft ever built, but it has its quirks. First, it has a free-castering nose wheel that can give pilots fits.

Entry is through a sliding canopy that can be flown opened—really cool!—but which can sometimes leak in heavy rain even when fully closed.

Climb performance is good at sea level, but as I would soon find out it’s poor at higher elevations. The Tiger has a service ceiling of just 13,800 feet. But the strong points of this airplane are numerous. The Lycoming 0-360 engine can propel it to 135-knot cruise speeds burning about 11 gallons per hour.

Who doesn’t want to fly that fast in an airplane with a fixed-pitch propeller and fixed gear? Handling is crisp and light, great for VFR flying, but not so much for tracking the ILS down to minimums. Need more cargo space for golf clubs, luggage or waterskis? Just put the rear seats down. This is a very desirable aircraft on the used airplane market.

After retrieving the keys from the FBO and topping off with fuel, I performed a thorough preflight, which included an inspection of the maintenance logbooks. I checked the logs, and like most planes I had ferried it had a high-time engine. After a run-up and pre-takeoff checks, I deemed the airplane airworthy and was cleared for takeoff. The little Lycoming O-360 ran well as I pushed the throttle forward and soon I was on my way to Prescott, Arizona, where I would spend the night. The next morning I was up at the crack of dawn and looking forward to what I expected to be an uneventful flight.

After takeoff from Prescott, I planned to make my next fuel stop in Las Vegas, New Mexico. The clear blue sky and phenomenal visibility lulled me into false sense of complacency. I soon had Las Vegas Airport (LVS) in sight and was cleared for the visual approach by ATC. It was about noon when I landed.

After landing, I shut down and opened the canopy. It felt comfortably warm. The sound of my entering the FBO awakened the lineman, the only other human at the airport. He took my fuel order and soon the Tiger was topped off, preflight complete and flight plan filed.

I told the lineman that I didn’t need to be marshalled out and he returned to his slumber. After engine start with all the gauges in the green, I noticed that I needed more power than usual to get the Tiger moving. I taxied to Runway 14, listed as 8,199 feet of asphalt, more than enough for my 180 horsepower Tiger to take off, or so I thought. I announced my intentions on the CTAF, lined up on the centerline and pushed the throttle forward. The Tiger’s response was lethargic to put it mildly. I checked the parking brake, because I thought maybe I had left it on during runup, but it was off.

Slowly the Tiger accelerated as I confirmed the throttle was fully forward. More than 8,000 feet of runway, I thought. No problem. Halfway down the runway I glanced at the airspeed indicator. It read 45 knots. Still, I thought, no problem. I have 4,000 feet of runway left, plus I want to get to Dayton tonight. Now with 75 percent of the runway behind me I could clearly see past the airport fence and the herd of cattle grazing contently on the other side. With the end of the runway clearly in sight, a quick glance at the airspeed indicator showed just 50 knots. My heart started to pound faster. Instinctively, I pulled back on the control yoke as the runway end markings came into sight.

The Tiger lifted off with stall horn blaring. I was flying…barely. I just passed over the airport fence and pushed the yoke forward slightly to remain in ground effect when I noticed the cattle were running. It amazed me how fast these 1-ton bovines could move when chased by a Tiger. After what seemed like an eternity I finally felt brave enough to see if I could climb out of ground effect. I did, at 200 feet per minute. The rest of the trip to Dayton was uneventful, but not without a valuable lesson learned. In my hurry to get to Dayton in a reasonably fast airplane and with VFR weather the entire route, I had allowed complacency to creep in by not checking the density altitude at the 6,877-foot elevation. It almost cost me. Fortunately, I learned my lesson without incident.

If you should purchase a Grumman Tiger, make sure you get a thorough checkout with an instructor who is familiar with it—and always check the density altitude.