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PUFA NEWSLETTER
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February 2, 2002
Ken Buck, President
Walter Klatt, Vice-President
Glenn Ursel, Treasurer
Daryl Hegyi, Secretary
Mail to: Pacific Ultralight Flying Association
102-16071 82 Avenue
Surrey, B.C. V3S 2L6
PUFA Newsletter published by Glenn Ursel
Editorial Note
by Glenn Ursel
I will be away working in Alberta for several weeks and so am forwarding this newsletter for February quite a bit earlier than usual.
At the January PUFA Meeting, Don Willoughby pointed out that I had failed to mention his amazing achievement at winning the candy jar contest at the PUFA Xmas Party held at Marilyn Parsons’ home on December 7th, 2001 by his closest estimate to the actual number of candies contained in a rather large jar. Belated congratulations to Don Willoughby!
Don Willoughby also mentioned at the meeting that he and his wife will be shortly moving back to Whistler where they had previously lived for several years. We will miss his enthusiastic support of PUFA flying activities but wish him well in his new ventures at Whistler.
I recently visited the local ultralight shrine, i.e. the Airflow Ultralight
Aviation Ltd. office down on the King George Highway beside the Serpentine
River and, during our idle conversation, Fred Glasbergen showed me a January
24th emailed news notice from a website called “Avweb” which cited a CBS
Evening News report that US Drug Enforcement officers were suspicious of
kitbuilt fiberglass airplanes such as one called the Velocity because “the
radar pretty much gets absorbed by the skin”. However, the Avweb
notice also cited an EAA response which stated that repeated research has
shown that the metal in the engine of fiberglass airplanes is more than
enough to easily allow radar tracking unless the engine has been modified
to shield it from radar detection which is said to be not an easy task.
Then the AVweb notice editorialized that the Velocity - a four place pusher
canard - is probably not the best choice for heavy hauling from short unimproved
airstrips. It went on to state that “what a drug trafficker really
wants is something like an Aerocomp Air 10 XL Turboprop. That aircraft
can haul an 800 lb load out of a 250 foot airstrip and cruise
for near 700 nautical miles at close to 200 mph.” The AVweb article
stated that as the post September 11th increased surveillance moves downward
from airliners through general aviation and onward to experimental planes,
it appears that ultralights might be next on the list for scrutiny.
Any ultralighters so inclined to such nefarious activities are therefore
warned accordingly.
With respect to the content of this newsletter, I noticed a very interesting article on the UPAC Website that was submitted by Jeff Stewart which tells some of the story of how Air Canada Flight 143, cruising at 469 knots on its way from Montreal to Edmonton on the afternoon of July 23, 1983, ran out of fuel at 41,000 feet over Red Lake, Ontario. In the cockpit, Captain Robert Pearson and his first officer, Maurice Quintal were among only a handful of pilots trained to fly the twin-engine 767, then the most advanced jetliner in the world.
If you insert “The Gimli Glider” into a search engine, there are several very interesting articles on this incident that describe the landing feat in even more dramatic terms than that of this one by Jeff Stewart. In researching the Internet for the date of this incident, I got the aforementioned information from another article published by Peter Banks on the web at: http://www.iasa-intl.com/GimliGlider.html
The article by Peter Banks indicated that the ground crew, with input from the First Officer, had used a factor of 1.77 lbs per litre as 1.77 kg per litre and consequently only put about half the required fuel into the airliner before takeoff. The saving grace, if you will, was the fact that Captain Robert Pearson was able to get the big plane down by side slipping it into the short runway at Gimli. Just like ultralighting, eh?
The Gimli Glider
While visiting my parents last Christmas in Victoria, my father gave me a copy of the book “Freefall” written by William and Marilyn Mona Hoffer. The cover contains overlapping images of a 767 in a sequence of rather alarming attitudes, from nearly inverted to vertical dive then all the way back to level again. If this doesn’t get your attention then the full title will: “41,000 FEET ... AND OUT OF FUEL - FREE FALL - A TRUE STORY”. Although the cover is misleading, the story is nonetheless remarkable in that it is not a work of fiction. Rather, it is a detailed account of the events leading up to an incident in which a 767 ran out of fuel at cruising altitude and performed a successful dead stick landing on an abandoned airstrip near Gimli, Manitoba. Most people now refer to this incident, and the aircraft involved, as the “Gimli Glider”.
This event was notable for several reasons, the most obvious being the skill demonstrated by the pilots themselves. In a last ditch attempt to quickly lose altitude on final approach, the captain relied on past experience as a glider pilot by putting the 767 into a severe side slip when only a few hundred feet above ground. And all this with two dead engines. In addition, this incident demonstrates that the chain of events in an accident sequence often starts with the tiniest of mechanical defects. In the case of the Gimli Glider it was a single imperfectly soldered connection within one of the two fuel quantity computers. In another more tragic accident involving a 757 flying out of Lima, Peru, mechanics failed to remove protective tape from the ends of the “static ports” (pitot tubes) after washing the fuselage. Upon taking off, critical instruments such as altimeters and air speed indicators were rendered inoperative, with the result that a perfectly sound airplane was flown into the Pacific Ocean. And all because of a 1 cent piece of adhesive tape. “Because of the nail the shoe was lost. Because of the shoe the horse was lost. Because of the horse the battle was lost. Because of the battle the war was lost.” - author unknown
What I found most surprising about the Gimli Glider incident, however, was the complex series of events which led to a multi-million dollar airplane with 61 passengers on board running it’s tanks dry mid flight. The more I read about aviation incidents and accidents, the more I come to realize that commercial airliners are often brought down by a surprisingly large number of interrelated factors. Given the right combination of pilot error, mechanical problems and/or unforseen weather, any pilot (767 or ultralight) may be at risk of having their “number come up”. With this said, however, pilot judgement (or lack of it) seems to be the one critical ingredient determining final outcome in an accident sequence. Often, a single decision can either make a bad situation worse or it can break the chain of events which link together to cause an accident in the first place. With all this said, here is a brief account of the Gimli Glider and the oversights, mechanical glitches, lack of communication and just plain coincidence which led up to it. Again, most of this information has been condensed from the book “Free Fall”.
1. As mentioned above, sometimes an accident sequence begins with the tiniest of mechanical defects. Within the “fuel quantity processor” (fuel management computer) of the future “Gimli Glider” was a single incorrectly soldered circuit. Because it allowed some current to squeeze through, the backup computer was inoperative as well.
2. No replacement processor was immediately available even though mechanics identified that the one on board this particular aircraft was somehow defective.
3. By pulling the circuit breaker for the defective fuel quantity processor, a mechanic found that the back up processor would function correctly (but only when the other processor was disconnected). This mechanic covered the pulled circuit breaker with yellow maintenance tape to prevent others from turning it back on. In this configuration, the aircraft’s electronic fuel gauges were operative.
4. Another mechanic later removed the tape and turned the circuit breaker back to the “on” position. Once again, all the aircraft’s electronic fuel gauges were blank.
5. Because the airplane’s fuel gauges were blank, the refueler had to rely on his truck’s gauges to tell him when he had delivered the 22,300 kg of fuel requested.
6. Canada had just turned metric, and this model of 767 was unique to Canada in being one of the first fully metric aircraft. Also, it had fully digital avionics resulting in the traditional analog fuel gauges being replaced with a cathode tube display linked directly to the fuel management computers. As we all know, however, computers are only as smart as the data which is fed into them. But more about that later.
7. Due to it’s advanced avionics and onboard computers, this 767 no longer required the use of a flight engineer who once occupied the third seat in the cockpit. Traditionally, the responsibility of calculating fuel load was that of the flight engineer. With no fuel gauges, the task of calculating fuel load suddenly fell to the unlucky (and unqualified) refueler.
8. Being unfamiliar with metric conversions, the refueler multiplied the number of litres by 1.77 to determine the number of pounds of fuel required. Instead, however, he should have converted litres of fuel into kilograms, a conversion which would require the use of an entirely different multiplier.
9. The flight management computer then had to be re-programmed manually by inputting the amount of fuel that they thought was on board. Of course, the inputted data was incorrect.
10. The flight management computer had no direct means of measuring the actual amount of fuel in the tanks so it relied on the incorrect data fed into it at the start of the flight. This proved deceptive during the flight since this same computer proceeded to monitor fuel consumption indirectly, making it appear as though fuel quantities were adequate. Are you confused yet? But wait, there is more!
11. The refueler had no idea where the aircraft was headed so he assumed that it was a short flight which required limited fuel. If he had been aware that the pilots were planning to fly direct to Edmonton without refuelling en route then he might have raised his concerns.
12. After consulting the onboard MEL (Minimum Equipment List), the pilot determined that it was technically illegal to fly the aircraft with all its fuel gauges inoperative. However, due to the recency of this particular model of 767, the onboard MEL was still considered a “working document” under constant revision. As a result, it was often viewed by pilots as “not being the final word”.
13. To further confuse matters, the aircraft had been cleared for dispatch by “maintenance control”. If the chief mechanic signed off this aircraft as airworthy then who was the captain to argue?
14. Once the airplane had been cleared by maintenance personnel, the final “go/no go” decision was solely that of the captain. Due to simple economics, however, there was a tremendous amount of pressure on the crew to fly. In this case that pressure was even greater since the flight had been delayed and both the flight crew and passengers were getting a little testy.
15. Reluctantly, the captain finally decided to fly the plane with blank fuel gauges, unaware of course that he had only about half the required fuel to complete the flight.
16. Upon takeoff, the 767 was about 10,000 kg lighter than normal due to its reduced fuel load. The flight crew may not have noticed this because on that particular day, the captain elected for a full throttle takeoff and therefore the rate of climb was already dramatic to begin with.
17. Somewhere over the lakes, bogs and spruce forests of northwestern Ontario, the last of the 767's engines flamed out. Soon after they lost most of their electrical power and shortly after that their transponder stopped transmitting information to Winnipeg Control. Luckily, however, Winnipeg Control just happened to have one of their old fashioned radar systems still operating - one that did not rely on data transmitted from a transponder. 48 seconds after disappearing from radar, flight 143 was picked up as a blip on the old radar system.
18. After initially being vectored towards Winnipeg International Airport, it was realized that the now gliding 767 did not have the altitude to make this destination. Luckily, however, the captain remembered an old abandoned World War II air base nestled along the east shore of Lake Winnipeg. And it was still within gliding distance....
19. Fortunately, the captain was a glider instructor in his youth and was able to successfully land the 132 ton jet on the Gimli “runway” (now an active drag strip).
20. Even though the Gimli “airbase” was crawling with local car enthusiasts and their families, the Gimli Glider managed to land without hitting any of them. It is quite likely, however, that the local Gimli Laundromat had a few extra customers later that day.
Air Canada Flight 143 after landing at Gimli Airport
So what lessons can we, as ultralight pilots, extract from all this? Perhaps I’m stretching it but here it goes:
1. Even the tiniest mechanical glitch, if not detected and corrected, can result in big problems.
2. The final decision to fly is always that of the pilot, not those staying back on the ground.
3. The more complicated the aircraft, the more things that can malfunction.
4. Even when everything goes wrong and all appears lost, the training and skill of a pilot can sometimes avert disaster.
5. Never rely on #4!
Jeffrey Stewart
(Originally published on the UPAC Website at: http://www.upac.ca/