Gimli Glider, Part II

When you run out of fuel in your Boeing 767, you get a 132 ton glider that is dropping out of the sky at 2,000 feet per minute. We pick up the story from yesterday with the plane at an altitude of 28,000 feet, or roughly 14 or less minutes to earth...with no power and no electronics except the radio.

There was actually a bit of power, just not electrical power. While the auxiliary power unit provided no electricity because it ran on jet fuel, the same source as the engines, there was a RAT onboard. RAT is the acronym for ram air turbine, a propeller driven hydraulic pump that had automatically dropped into the air flow under the plane when the engines stopped. The RAT supplied enough hydraulic pressure to steer the aircraft and to enable a dead stick landing.

On the ground, controllers were scrambling to find a place for the airplane to land. Quick calculations showed the craft with a glide ratio of 11:1, that is 11 forward units for each 1 unit of descent. The RAT had created extra drag, so the rate of descent had increased. Winnipeg airport was out of reach. The last option for a landing strip --as opposed to a landing "spot" -- was Gimli, an abandoned Canadian Air Force base. Co-pilot Maurice Quintal was familiar with Gimli,, having been stationed there while in the Air Force.

What neither the pilots nor the ground controllers knew nor had time to research was that since the Air Force had left Gimli, runway 32L had been reconfigured for local use. Gimli was now an amateur auto racing track. The left runway had a steel guardrail down the middle, a safety precaution for the dragstrip it had become, and an impeding on the landing strip it was about to become.

On the ground at Gimli, there was no drag racing this day, but that wasn't good news. It was Family Day for the Winnipeg Sports Car Club, so there were go-kart races, road races, campers, kids everywhere, everyone having a great time. The last thing they all expected to see at the former airfield was an airplane attempting to land.

Back on the airplane, the pilots had discovered that the RAT didn't supply enought hydraulic pressure to force the landing gear into position. Co-pilot Quintal hit the button to release the landing gear and heard it drop into place. Indicator lights showed the new problem: the nose gear had not locked in place.

It was six miles to Gimli.,at an air speed of 180 knots or so, just two minutes or so remained to get the big machine lined up to land. Pilot Pearson needed to both slow the airplane and descend. Without the power needed to employ the airbrakes, the only way he could simultaneously accomplish slower and lower was to throw the airplane into a side slip. That involves using the surface of the airplane to catch the air. To do that, the plane must no longer be pointed into its path like an arrow. The plane gets re-oriented so it's like a big "X" moving on the line of flight, belly first. When Pearson threw the plane into the side slip, half the passengers looked out the window at nothing but blue sky while the other half were staring at the ground, all this in silence, adding another element of terror to the occupants of the stricken airplane. Fate had reserved one positive for the passengers and crew of Flight 143. Robert Pearson was an accomplished recreational flyer in sailplanes, or gliders. This side slip wasn't foreign to him, though doing it with a crippled Boeing 767 was never part of any plan.

Once the correction in height and speed was deemed done, the precious seconds ticking away, the enormous airplane had to be wrestled back into an appropriate orientation to land. The side slip maneuver had reduced airflow to the RAT, so Pilot Pearson had an enormous physical challenge simply to reorient the craft. Further, by changing the plane's attitude, Pearson had been unable to see the landing strip--and the guardrail that bisected the runway he was about to attempt to use.

The people on the ground, the Winnipeg racers and their families having their day of fun, heard nothing, no whining roar of jet engines to warn them that there was an airplane falling out of the sky into their picnic.

Pearson righted the plane at the last second. As it touched down, the pilot locked up the brakes. The explosion of the landing gear tires as they blew was like a cannon announcing the danger to the race crowd at the other end of Runway 32L, a mile straight ahead of the two and a half million pound machine that had come from nowhere and was headed right at them.

The partyers on the ground ran for their lives as they realized the beast was headed toward them.

The nose of the plane slammed to the ground, sending a 300 foot tail of sparks behind the plane. Pearson saw the guard rail and steered with the brakes to straddle the rail between the locked in rear landing gear. The right engine nacelle hit the ground as the plane charged ahead. The mile interval of landing strip raced past in seconds.

Less that a hundred feet from the people and their toys and their campers, silence, as Flight 143 came to a halt. The cheers from the passengers were short as small fires broke out on board, and the car club members, in mortal danger seconds earlier, came running with their fire extinguishers to help.

There were only minor injuries, those sustained exiting the aircraft via the emergency slides. Damage to the airplane was so small that the craft would be repaired and flown out of Gimli-- just two days after the amazing landing.

Nearly 25 years later, Pilot Robert Pearson and First Officer Maurice Quintal flew that same airplane out of Montreal to its retirement at the Mojave, California airport. They were accompanied by three of the six flight attendants who were on the plane on July 24, 1983 when the incredible landing was accomplished. The photo below is from the good-bye fly-by over Montreal airport.

The Gimli Glider

While looking through the aeronautical information that has caught my attention over the last few days, I found a story about an airplane landing every bit as tense and thrilling as the recent splash landing in the Hudson River. This one happened 25 years ago.

One July 23, 1983, a Boeing 767-200 ran out of fuel 41,000 feet over Alberta province. The airplane had taken off with malfunctioning fuel gauges and the flight crew was aware of the problem. As a work around to the broken fuel gauges problem, the ground crew had dipped the tanks, that is, they put a stick in the tanks to visually read the amount of fuel the airplane was carrying. This was an accepted method of determining the amount of fuel onboard, though it required a second step, a calculation.

In the second step the crew was required to calculate the amount of fuel by applying a factor for the specific gravity of the fuel.

The crew did the calculation several times to be sure there was no error. They made the same mistake each time. Because the crew used the wrong conversion factor, the airplane had about half the fuel required to make its Montreal to Ottawa to Edmonton flight. Eight miles high there are few options. You can't watch the signs for the next gas station. Here is the start of what transpired onboard.

The passengers had just finished dinner when a warning light came on in the cockpit. The flight crew thought that they were dealing with a failed fuel pump in one wing tank when a second warning light came on. The crew immediately made plans to divert to Winnipeg as the left engine flamed out.

Pilots Bob Pearson and Maurice Quintal immediately began making preparations for a one engine landing in Winnepeg. Then another fuel light lit up. Two minutes more, just as preparations for the one engine landing were being completed, the warning system issued a sharp "bong" noise, an indication of the complete and total loss of both engines. The pilots said they had never heard the sound before.

The sound is not in the flight simulator.

After the "bong," things got quiet. Quiet at eight miles up isn't generally good. The fuel tanks were empty and both engines had flamed out.

Tomorrow, we'll continue with the story of the big, heavy jet airplane that had suddenly become a glider, a glider that was descending 2,000 feet per minute.