This trip took place back in the mid-1970’s: flying down along the western coast of Mexico and meandering down to the South American continent sounded like just the trip these US-worn pilots needed — until… When I think of this story, it still gives me the chills.
THE FIRST LEGS of the trip went well — very well. The tour guides had everything set up, from where they would stop, to the hotel accommodations that they would be staying in. The rooms were nice, the people were nice, and the fuel was clean and relatively inexpensive. The trip was turning out better than any of the pilots could have imagined, because their spouses were having so much fun, that they were enjoying the trip, too.
ONE LEG AFTER ANOTHER of the flight was peeled off, as the group of planes headed south towards the southern continent. Still, the longest leg in the journey lay directly ahead — a leg that, while well within the fuel capacity of some of the planes in the group, was not quite so gracious for others.
ARE YOU WORRIED YET? If you aren’t, then you should know that this leg would also be flown over a fair portion of the Pacific Ocean. If someone got into trouble, an off-field landing would likely mean a water landing, although there was a ghost of a chance for a beach landing.
DESPITE SOME CONCERNS, a good forecast was enough to convince all the pilots in the team to launch southward. They flew a steady course, navigating mainly by ADF — no GPSs. The hours ticked away as they made their way south, following the coast at a safe distance, their attention kept rapt by the verdant jungle that passed off their left wing tip.
AFTER ABOUT THREE HOURS, the pilots in the Cessna 182s started to get a little nervous. It seems that the winds aloft were a bit off of the forecast and their fuel gauges were approaching empty. In fact, their fuel gauges were already reading EMPTY, but the engines were still running, and it hardly seemed like a good thing to question at that point.
SOME BETS YOU TAKE, SOME YOU SHOULDN’T. A few minutes later, some 25 miles from their destination, the first 182’s engine began to stutter. It was nearing the death throes of fuel starvation. One pilot had run slightly more rich of peak than his counterpart — thinking that was better for the engine. Now he might lose the plane… and a lot more. As the plane started to lose altitude, the party started to get a little excited.
WHEN THE FUEL GAUGES READ EMPTY, there isn’t supposed to be much fuel left. At some point, empty means empty. Such was the case for our 182 pilot. He tried switching from BOTH to LEFT, and then to RIGHT, with no change in the engine’s performance.
OUR PILOT WAS ABOUT TO GIVE UP, AND PREPARE TO DITCH when one of the flying tour guides spoke up. “Select the right fuel tank, and put the plane into a slip to the left,” he directed the 182 pilot. With nothing to lose, the command was followed to the letter. The engine on the plane immediately gained power, and began to run smoothly.
THE MILES SLIPPED AWAY, as our pilot maintained elevator, aileron, and rudder pressure to keep the plane on course. A few minutes later, the tour guide instructed the pilot to swap the slip and fuel tanks, which he did — with hardly a hiccup from the engine. Soon, enough miles had gone by that the 182 had reached the airport… and was the first to land.
SO, WHERE’S YOUR FUEL PICKUP? While the pilot was preparing for his swim, the tour guide, was thinking of ways to scavenge ‘unusable‘ fuel. The tour guide told the pilot to slip the plane to the left, and to select the right fuel tank. The right wing went high, and the unusable fuel that was still in the right tank flowed to the lowest point — and the fuel pickup!
By repeating the process, the pilot was able to access the extra 4 to 5 gallons of unusable fuel that was left in the wings. In doing so, the tour guide saved an airplane and helped the pilot avoid an early dip in the Pacific Ocean, which would have most certainly resulted in the total loss of his aircraft, and the potential injury to his family.
FUEL — INFLIGHT CALCULATIONS. If the pilot had been smarter, he would have calculated his fuel burn by the mid point of the trip, recognized the adverse headwinds, and turned back. I guess “staying with the pack” was too strong of an instinct in this case — that, or our pilot had a near-fatal case of Get-There-Itus!
BOTTOM LINE: Unusable fuel is fuel that can’t be used normally. In an emergency, all bets are off, so use the fuel you have, and if necessary, try slipping while selected to the opposite tank. Just don’t expect the engine to keep running if you’re lucky enough to fly a proper approach.