Thursday, 30 October 2014

ENGINE FAILURE

In learning to fly, we all have to spend a minimum number of hours practicing emergency landing procedures, the most common of which is an engine failure. If your engine conks out, you just cannot coast to the side of the road then try to investigate the problem, or call a tow truck. Oh, there are tow trucks specifically designed and built to tow aircraft but they fall short of picking up that stranded airman at the edge of Cloud 901, just off the intersection of Luminous Lane and Cumulus Crescent. No, if you encounter an engine failure, you have to find a place to put the plane safely on the ground (rather than let the plane do that because the plane itself isn't all that fussy), then call your tow truck.

When we do our Flight Test, which is showing the examiner that we are indeed capable of handling an aircraft and all the hazards that some with it, we have to show specifically that we can handle an emergency. For example, you'll be on a cross-country flight. The examiner will ask you to note your check point then point it out to him both on your chart (map) that you have either strapped to your leg or on a clipboard located between the two front seats. The moment he is satisfied, he'll suddenly shut  the fuel off, feather out the prop, and tell you that the engine has seized. You'll notice that the prop is standing still, which is unnerving in itself.

Well, the first thing you do, is try to find a safe place to put down. In farming country, a stubble field or a smooth pasture will be first and second choices; summer fallow or a road would be your last. You keep the airplane straight and level while you set yourself up to land. You then get on the radio and notify Flight Service that you are declaring an emergency, and give the operator your location. From there on, it's concentrate on lining up your airplane, keeping it level and making sure that you're going to actually make it to that selected spot. You may have to use the ailerons, rudder and elevators to lose altitude quickly if you may be too high; but you were taught how to do that--right?

Your field is all lined up, and it looks like you're going to actually succeed in landing with what is often termed: a Dead Stick. You're getting into the ground effect and you think that your examiner is really expecting you to go through with it, then suddenly he moves the fuel control to Full Rich, hits Start and the engine spins back to life. You 'firewall' the throttle and you begin to pick up speed, and soon ascend back to regulation flight altitude.

You passed the test, except when the examiner tells you that maybe the stubble field would've been a better choice than the summer fallow field that you did choose, right beside it. At any rate, the examiner is confident that you are capable of landing--Dead Stick--and staying safe.

After several hours of classroom time, dual time and solo time, you have successfully met the requirements of a Private Pilot and received your wings. Then you have the opportunity to fly whenever and wherever you want. The flying hours add up and your skills increase even more. Sometimes, in order to keep your skills sharpened, you simulate many more engine failures and are happy with the outcome. The passengers you have with you might not be willing to share your enthusiasm but that's their problem. At any rate, you know how to handle an emergency but you never think you're going to face the real thing.

There are two kinds of pilots: those who have experienced an engine failure in flight, and those who are going to.

Scotty received his wings back in the 50s. Being a farmer in the Milk River area, he flew planes for a number of owners, doing a number of things such as counting livestock or finding out where the cattle all went, but that type of work was sporatic and didn't support owning a plane of his own. One day he decided to embark on a more stable (read: lucrative?) business involving flying. Since he already flew for Aime, spraying crops, Scotty made a deal to buy Aime's Piper Super Cub, which was already equipped with spraying apparatus, and do it all for himself.

For years Scotty's Cub could be seen from early June until well into the fall. He sprayed field after field, and then even found some time to remove the sprayer tank and use the back seat for a real live passenger. His continued flying added up the hours, and of course, after so many hours, certain maintenance requirements are needed to keep the plane in the air.

One of the most major parts of aircraft maintenance is an engine overhaul. During the war, that often meant that the engines had to be gone through as often as every 250 hours. Peacetime might have stretched them out to 750. Most civilian planes needed engine majors every 1,000. Modern private planes can run up to as much as 2,000 hours before they need to be done. The bottom line is that government regulations dictate that the engine must be completely disassembled, inspected and rebuilt to original specifications at the specified hours of use as stipulated by the manufacturer or the airplane will not be allowed to fly again.

Now just think if those rules of maintenance applied to our regular family cars?

The engine in Scotty's plane needed to be overhauled every 1,000 hours of operation. Having accepted that, Scotty made arrangements to get the job done, maybe over the years, three times. In this case it seems to me that the engine had been overhauled before, at least once. Anyways, he flew his Cub up to Taber, to Ray's shop, where the propeller was removed, the engine pulled and the two of them sent to the repair shop--the engine for its scheduled overhaul and the prop for its certification.

I might add right here that Ray was qualified to perform engine overhauls himself but with other maintenance procedures that needed to be done, sending the engine to the repair shop allowed him time to work on other parts of the plane.

In due time, the engine came back, all signed and certified, and looking very much like a new engine. Ray installed the engine, the prop, then started it and took the plane for a couple of circuits (take-offs and landings) at the local strip. Everything OK, Ray signed it off and called Scotty.

Scotty got in, gave it his own checks then waved to Ray and flew away south.

Everything checked out as good as could be expected. Oil pressure, cylinder head temperature, all gauges showed where they should be. Scotty flew across Highway 3, and using Highway 36 as sort of a guide, continued along his way.

About twenty miles south of Taber is Chin Coulee, which also contains an irrigation reservoir called: Chin Lake. Not a heck of a lot of imagination there but at least it got named. Approaching Chin Lake, one can see the Wrentham elevators about five miles south. Scotty had seen this same sight countless times, and it hardly registered anymore. However, this time would be a little different.

Just as he cleared Chin Lake and was 'feet dry' over the farmland again, the engine started to labor and lose rpm. Hardly before Scotty could read his gauges or attempt to see what had gone wrong, the engine let out an ear-splitting squeal and seized, causing the plane to lurch sideways. The prop stood still, the blade listing maybe ten degrees past center.

Scotty was shocked. He stared at that frozen prop blade in disbelief, trying to understand what had just happened but when the airplane began to lose speed and altitude, reality began to close in fast. After over four thousand hours in the sky, he had just witnessed his first engine failure, and his next major task was to get the airplane on the ground. Safely!

Being springtime, a lot of stubble fields were there for the choosing. Scotty picked a suitable place, not too far off the highway, lined up for the landing, and called it in. He touched down exactly where he thought he would and allowed the plane to roll to a stop, miraculously close to an approach then waited for the rescue party (parties) to arrive.

Now I'll have to add another little tidbit of information here: Scotty was an experienced sprayer pilot and flew like a typical sprayer pilot. Flight regulations dictate that you must fly at a specified distance AGL (Above Ground Level) which is in the neighborhood of a thousand feet up. That helps to ensure that you clear most obstacles on the ground (most big cities would still pose problems there). It also helps you to safely find a place to land your plane--and actually land it--in case of an engine failure. Unfortunately, since sprayer pilots are used to flying at about cattail elevation, they have a little less time to execute emergency procedures. Yes, they can clear a fence and fly under a powerline at the same time but flying at Circuit Height? Na, takes too long to get up there, and too long to get down.

Back to Scotty, the fire department, ambulance, police, air rescue, ground rescue, local peeping toms and maybe even some local dogsled teams all converged on the airplane. Scotty was checked over and deemed to be only a little shaken. The crew removed the wings from the airplane and it was towed back to Taber.

The engine was removed and sent back to the repair shop which determined that a main bearing had spun causing the seizure. Repairs were done, the engine shipped back, installed, tested, and Scotty was notified.

Once again, everything went quite well, Scotty was flying home, at a little higher altitude this time and he was ready to take on his customer orders...

Well, just across Chin Lake and that same loss of power, followed by that same screech, the whole aircraft shuddering and the prop stood still--again! Only the prop was at maybe a 45 degree angle, but I never heard of anyone taking a protractor and measuring it.

Once again, Scotty had to pick a place, line up the plane, call it in, land the plane, and wait for all the officials and rescue crews to arrive. Once again, Scotty was checked up and deemed to still be a little shaken up but there was also a little bit of an angry demeanor as well.

Once again, the plane was partially dismantled and hauled back to Taber; once again the engine was sent to the repair shop, which, once again, determined a spun main bearing and consequently, a second destroyed crankshaft.

Once again, the rebuilt engine was installed, tested--more vigorously this time--and Scotty was, once again, on his way home.

The first engine failure scares you to death; the second one has you a little on the apprehensive side; but the third in a row has you saying things to flight service that might not be deemed appropriate for proper communication. No doubt, there were some adjectives directed to the repair shop, toward Ray, and probably to the founding fathers of this nation.

When Scotty experienced the third failure he was determined to take that engine to the shop himself and give it to the mechanic more as a suppository. He was angry!

Maybe a good thing he wasn't Irish or he might have made good on that promise. Of course I've known a few Scots who could be just as irascible...

This time the repair shop prepared a complete new engine and sent it down. The failed engine was completely dismantled and inspected by a team, who, the first time over, couldn't determine why that one main was seizing up. Oil starvation was behind it but the gauge showed full pressure right up until the engine seized. It was finally determined that an oil bypass valve had inadvertently been installed backwards, causing it to block off the flow of oil to that one bearing when it got hot.

Some red faces; many apologies, and maybe a few more descriptive terms and the airplane flew home safely to resume its role as sprayer. In reflection, Scotty understood what happened, and when his plane came up for a final major, the services of that same shop were engaged.

No lasting hard feelings...



4 comments:

  1. Whew! What a story!!! Three - times the charm? Strikes and you're out?
    That man needs to go out and buy a lottery ticket!
    Then let's make him the next flight examiner. He's done it more than ANYBODY!!!

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    1. Listening to Scotty describe it was absolutely priceless. I tried to capture that same feeling but probably fell somewhat short. However, that's the story, as told by Scotty and scribed by me. Glad you enjoyed it.

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  2. Wow what a story! I don't know what it says about me but even after that story I have always dreamed of flying one of those planes. I've never even been up in one but one day...it's #1 on the bucket list. Most girls dream of being Miss America (or it's Canadian equivalent haha) I always wanted to move to Alaska and become a bush pilot! I recently took my first helicopter trip and it was amazing!

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  3. Hi Rena. Flying always intrigued me and was able to achieve my dream of becoming a pilot. Unfortunately it got too expensive to be able to fly steadily but I have sure enjoyed my hours behind the controls. I spent some time in the Athabaska Tar Sands and got flown out in the bush on a few service calls. Those bush pilots are a crazy bunch but they know their business. A helicopter is a different experience for sure but it is addicting. If you want to fly, go for it. Controlling the plane is an experience you'll never forget. Thanks for stopping by.

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