CanadaNew BrunswickSunbury County45°53’27” N 66°45’24” W October 10, 2017 in Canada ⋅ ⛅ 21 °C
This is intended to be the final wrapup. So it is in fact part 7 of 5. Since the last note I reported my test results and hypothesis for the failure to Pipistrel. On September 14 I had a phone call with the head of engineering. They were able to reproduce the failure scenario by following the same method I had.
They acknowledged that this is a real problem and are changing to a left hand thread as I proposed. They discovered that clearances are so tight that some bolts, although technically withing specification, but at the upper end of permissible tolerances can have some interference between the top of the rotating screw and the the stationary captive structure. That provides a screw loosening torque.
Presently they are going through the process with the Slovenian equivalent of the FAA to verifying the will eliminate the failure case. Then the applicable documentation and information dissemination will occur. This will include a change to their current manufacturing to use left hand threads as well as instructions for inspection for and replacement of existing interfering screws where found.
QEDRead more
CanadaNew BrunswickSunbury County45°54’15” N 66°45’10” W
August 17, 2017 in Canada ⋅ ⛅ 21 °C
This is the final part of the Emergency series (part 6 of 5). After examination and testing of the propeller pitch control mechanism, I am confident that I know the cause if the propeller/engine failure.
GUFY's pieces were collected and removed to Red Lake. The salvage operator did some preliminary examination at my request. He confirmed:
The engine was not seized. It could be moved part of a revolution before being blocked.
The propeller pitch could be changed by hand.
The pitch control linkage was intact from cockpit through the bellcrank and to the forked rod that attaches to a bearing connected to the spinning propeller hub.
My working hypotheses was that something had failed in the pitch control mechanism that allowed both blades to feather together. If only one bladed feathered, that would set up an intense vibration. That never happened.
The forked rod goes through a hollow gear in the engine to the propeller hub. I had figured that the forked end had lost its attachment screw to the bellcrank. But it was still attached.
The forked rod attaches to the propeller hub through a ball bearing that has the prop hub shaft attached by a screw to the inner race of the bearing. I knew that screw could not fall out because the other end of the forked shaft allowed very little movement before being stopped.
So I asked the salvage operator to ship the propeller hub and linkage mechanism to me for further analysis. After sending him removal instructions he extracted the propeller hub easily.
But he forgot to perform the first step: remove the bolt attaching the forked shaft to the bellcrank. That step was necessary to allow the forked shaft to pass through the hollow gear. The shaft stayed behind and the hub easily came out since the screw attaching the hub to the bearing was completely unscrewed!
Aha. Although the head of the screw was prevented from unscrewing at its end, there was nothing preventing the propeller from unscrewing itself from the other end. Technically the bolt was specified to use blue Loctite to keep it in place. Blue Loctite was used but apparently failed.
After receiving the parts, I confirmed the inner race of the bearing still turned freely.
Ironically, to reconnect that screw to the prop hub requires removal of the forked rod first to gain access to the hex head of screw. The screw could be fully reattached to the prop hub.
To test if the prop hub could unscrew itself I separated the two parts and then turned the screw one turn before remounting the forked rod. After spinning the prop around the stationary bearing and forked rod, the attachment did loosen until the propeller hub finally separated and fell on the ground. I repeated the test with similar results.
Although it took some time for this separation to happen, at cruise speed there is a relative motion of approximately 40 revolutions per second which is considerably faster than my hand twirling of the prop.
When did the screw first become loose? Before the trip the propeller and hub had been removed for its 600 hour maintenance. The forked rod attachment to the bearing was verified to be tight at that time. Before the first flight of each day, the propeller blades are cycled by hand from fine pitch to feathered. As part of each preflight, with the engine operating, pitch is moved from fine to coarse and then back. When transitioning from climb to cruise flight pitch is again changed to coarse.
Engine load increases significantly for small pitch changes when the pitch is coarse (cruise mode). That was not observed on the final flight. So a gradual loosening of the screw during flight over even a few seconds did not occur.
Apparently a sudden removal of the screw enabled the propeller pitch to be changed. The only force available to change the pitch at that point was aerodynamic force on the propeller blades. It is equivalent to having the tail suddenly removed from a aircraft. This is an unstable situation where, depending on the angle of attack of the wing at that time, the aircraft will either immediately pitch up or pitch down. Similarly the propeller will either go to minimum pitch or fully feathered. Fine pitch would have been preferred: the throttle would have to be reduced and I would have to fly slower. Evidently my propeller slammed into full feather, the sudden load abruptly stopping the engine.
All aircraft using the Pipistrel Vario propeller could be susceptible to this unintended feathering failure. That includes the 80 hp Pipistrel Sinus and Virus series. The 100 hp versions use Woodcomp propellers that do not feather. Presumably they are not susceptible to this kind of failure.
The control linkage must be removed to change the blades, balance the prop or change the base pitch of the blades. I have changed blades five times and tweaked pitch more often than that.
So the screw needs to be removable when wanted. Looking at the design of the blade pitch control mechanism, space restrictions limit modifications to prevent unwanted screw loosening. Blue Loctite helps. One easy change would be to use left hand threads on the screw. Then propeller rotation would tend to retighten the screw rather than fling it away.
The pictures show the afflicted mechanism. The first is a shot of the screw in the bearing taken at Red Lake just after the propeller was (surprisingly) removed. The threads of the self-unscrewing machine screw are visible in the centre of the bearing. Note that the seal for the bearing is missing, along with a few balls. Apparently the suddenly unattached prop hub shaft rattled around a bit before exiting to its feathered location, banging into the press-on seal.
Curiously the seal was trapped in the engine prop mechanism. I received it with the rest of the prop hub assembly. The second picture shows the bearing after I popped the seal back in place. The third picture shows all the components: prop hub, hub extension, bearing case, forked rod, and the 'fork flange bolt'. The fourth picture shows the inside of the hub, including the mechanism that controls the pitch of each blade. All is normal here.
So what's next. I will forward my pics and thoughts to Transport Canada to add to their accident file as well as to Pipistrel and the Yahoo Pipistrel group.
As for me, I am recovering well from my broken leg. The impact broke my tibia near the ankle. They put a titanium tube down the centre of the bone and screwed each end into the bone. The fibular was more of a mess. It broke in three places, once near the top and 2 more places near the bottom. It was left to heal on its own.
Radiography (I do not like the term X ray when I am involved) were taken just before two months had elapsed since my operation. The tibia is mending well and I was surprised to see bone growth had bridged all the gaps in my fibular. I have been walking without a cane for some time, my limp gradually fading.
The bone doc said I will be able to do anything I wanted with my leg. I am happy to now being able to run marathons. Couldn't before.Read more
CanadaNew BrunswickSunbury County45°54’15” N 66°45’10” W July 3, 2017 in Canada ⋅ ⛅ 25 °C
This particular note is directed at fellow GA pilots. I am assuming the reader has read my previous footprints in the "Emergency:" from this trip. Contemplating my recent unpleasantness plus a couple of other recent events produced a eureka moment to a question that has bothered me for a very long time,"Why are there still so many serious accidents after an engine failure?".
The first event was a recent article from avweb.com stating airline safety, while excellent, keeps getting better. On the other hand, GA safety has remained essentially unchanged at a much lower value for the last 20 years.
The second event was my botched circuit during my forced landing. At one time good circuit planing and execution was thoroughly ingrained in me. I thought I could not do a bad circuit if I tried. I even spent time to wallow over my current ineptness as soon as I realized what I had done... before I had landed!
The third event happened in Prince Edward Island. It was a mundane forced landing after an engine out. The pilot said he was simply doing what he was trained to do.
Then it all fit. Training. He was right. When I was flying gliders 30 years ago, I got forced landing training every time I flew. But no matter how ingrained something might have been long ago, it will be 'degrained' if not practiced.
What about other GA pilots. Most GA pilots have no glider training. Most never practice forced approaches after they get their license. And how useful was that training? There are two training practices I would like to see banished.
The first is the 360 degree circular pattern. This is in the Transport Canada Flight Training Manual. I had to get an exemption to do a 'standard' circuit. The 360 degree requires a descending 360 degree turn to flare. By definition that is an unstable approach where you have to hit a point in space. In a conventional circuit your goal is to hit the final glide path at some point. From then on your landing is like any other.
The circular pattern leaves no opportunity to compensate for winds or any lift or sink encountered on the way to touchdown. These might be of less importance when flying a jet that with an approach speed speed of 130 knots. Typical GA planes will be less than half that.
The second practice is that of the 'power off 180'. It is used frequently at the local commercial airport. On late downwind engine throttle is pulled to idle. The student is expected to continue on his downwind (to the usual point?) then turn. There is not enough height for a normal base so there is typically a Pythagoran attempt at a solution where a diagonal approach is made to the threshold with a very low altitude turn at the end to line up on the runway. If it does not work out they just add some power. How is any of this representative of what a real power failure would or should look like! These poor people will associate a power failure with cruise along for a bit then do a 180 degree or some weird diagonal path to meet their destiny on the ground.
But I said I had a eureka event. Yup. I believe the solution is regular training. Relevant training that simulates realistic engine failure situations. Dual training can get expensive fast, especially if you have to rent the plane too. True. There are some ways to reduce the costs and still get some effective training. I will discuss those after discussing training in general.
Maintaining IFR currency is hard. Practice is needed to meet the standards. Many certified activities require regular retraining to remain certified. For example CPR. Professional athletes have training camps and permanent coaches.
There is no reason to think flying is fundamentally different than every other activity in the universe. If you do not try to get better, you will get worse
There are three kinds of training, dual instruction, practice, and mental training. Dual instruction and practice involve skills development, scenario simulation and muscle memory. Mental training is stocking your brain with good ideas that can be explicitly called upon during decision making in the planning phase of the emergency response. Imprinted thoughts may also appear, unbidden, during the emergency when some part if the mind determines makes a connection between what is happening and a particular thought. An example of that would be the "Don't turn away from the airfield" line that popped in my head while executing the S turn on final. In that case I just accepted it immediately... with less than an ideal consequences.
Look for examples and ideas on how to handle particular emergencies. Listen to hangar flying and other pilots relating their own experiences. Many of these are free or have very low cost to access. Read accident reports or their summaries.
Regardless, think about what you read or hear before accepting. Beware of obviously bad advice. One of the worst I recall being published was the recommendation of doing a rate 1 turn if you have an engine failure after takeoff if you decide to turn back to the field. That's 1 minute to do a 180 degree turn. That shallow a turn would also cover a lot of landscape.
Being comfortable with power off circuits and landings is a critical practice. I had an advantage with my Pipistrel. Its standard technique was to be on idle from late downwind. Glidepath control was with spoilers acting as a negative throttle. Few other GA aircraft use spoilers. For the remainder, I recommend getting comfortable with side (forward) slips and slipping turns. When doing power off landings, give yourself a chance by picking an aiming point down the runway instead of at the threshold.
On the other hand, the style my mind works put me at a disadvantage. There are two extremes of mind functioning style. Regimented functioning has the mind following steps in a specific order every time. Think of a drill sergeant. Free style thinkers are always open to new ideas whatever the source. Being sidetracked from the task at hand is easy. Think absent minded professor. My mind functions closer to that end of the spectrum.
How I tried to compensate was to set aside two pieces of my mind: one was to check I was not going to panic; the other was to observe and note the what was happening. I see now that was insufficient to prevent being sidetracked. What would have been better is to replace the observer 'task' a with check_ok task. Its job would be to do a quick validity check that I was still doing the right thing. Anything resembling gazing, or fascination would be confirmation that I was sidetracked. Perhaps it could be considered a dumbass alert.
I used to glibly say, "As long as you don't panic you will probably at least limp away from a crash". I no longer think that is adequate. I think there are two requirements for a high probability of survival: don't panic; prevent zombie mode.
Two things are necessary to prevent zombie mode: relevant current training; prevent being sidetracked. If you are appropriately trained, it will take say 10% of your brain to perform the procedure. The rest of you brain is available for dealing with everything else such as crosswinds, wind shear, obstacles, powerlines and avoiding zombie mode. If you are unprepared, easily 90 or perhaps as much as 110% of your brain is needed to perform the procedure. Oops.
I may have some details off but I feel strongly that the main points covered here are correct. But I could still be wrong. I would like these thoughts to be widely discussed and argued for or against with other concepts out there.Read more
CanadaOntarioEar Falls51°0’10” N 93°14’29” W July 2, 2017 in Canada ⋅ ⛅ 19 °C
So what if I had made all the right decisions and executed them perfectly? How different would the outcome have been? Is there anything to be learned by studying what happened?
I'll answer the last question first. You can always learn from others or your own experiences.
First let's go to the starting point of the emergency. What caused the propeller to feather and the engine to stop? Unfortunately that cannot be answered yet. The Transport Safety Board said their investigation of this incident will be limited to gathering and filing data. Evidently they feel their finite resources would serve aviation safety better if they were used on more common aircraft failure scenarios, especially since injuries were (relatively) minor and property damage was nil. I cannot fault them for that assessment but it does leave me as the sole driving force looking for a solution.
The uncommanded feathering of the propeller is key. Pitch is controlled by a mechanical linkage. The propeller stopped vertically so that I could only see one blade. But both blades had to be feathered otherwise there would have been massive vibration.
Looking at the pitch control mechanism, there are only 2 points of failure that could allow the prop to get to a feathered position without being commanded it from the cockpit:a spring and a bolt that attaches the prop control rod from the hub to the position lever. If either of those disconnected somehow, only aerodynamic forces on the prop blade determine the pitch.
Nevertheless, I would be surprised if Pipistrel would allow a design that could fail leaving the propeller feathered. More likely is that there was some variation in my installation that allowed this failure mode. I have contacted Pipistrel regarding the failure mode.
Now for how the emergency situation was handled. From the breadcrumb file, there was about six and a half minutes from prop failure to impact. In these situations there are no certainties, you are just trying to choose the way that maximizes the probability of a safe outcome.
It is clear that planning was better than delivery. If I had to do it again, I would still pick the wide upward grade. Trees would probably have been ok but more of an unknown for me.
It was good that I planned to establish a standard circuit about the flare/landing point. It was good that I was vigilant against succumbing to panic. It was also a good idea to seek solutions that did require great skill to perform in my adrenalin compromised state.
Getting diverted by the radio while wrong had little effect on the outcome in this case... only because there were over 6 minutes before impact. But it still would have been better to have declared the emergency, given the latitude and longitude from the beginning and, once sure they got that right, signed off from the radio and shut it down.
The fixation on the landing area was another matter. It allowed me to unwittingly drift too close and low to the landing site. It is hard for me to over-emphasize the shock, wonder and disgust I felt when I realized I had botched the circuit. In my gliding/instructing days circuits were my specialty. Every landing was a spot landing where I had intended it to be. Complications like other aircraft, winds or high lift or sink encountered were handled easily.
This time I ended up too high and too close on final for spoilers to be sufficient to get down to the threshold. That led to a snap decision to do a figure 8 bowtie to lose altitude while consuming less runway. Unfortunately I had never done this on final and I did not perform this higher skill maneuver as planned, ending far down the runway. From examining the breadcrumb file, full spoilers and full flaps would have used a bit less of the runway than actually consumed.
Let me be clear, the biggest mistake was allowing myself to get diverted from the planned action to an irrelevant analysis of the already selected landing site. The second biggest mistake was not realizing that I had allowed myself to drift from the task at hand. That is not as bad as blind panic, but it was pretty bad.
If things had gone as planned, almost everything would have been routine. I would have reached final with full flaps and using spoilers to control the glidepath to the flare point. That would have led to a lower touchdown/impact speed and since energy varies with the square of the speed, less impact energy to dissipate.
Nevertheless, for this case, it is probable that there still would have been significant damage, although possibly less destruction to the aircraft and perhaps no broken bones for me. Since the sandy surface was fairly soft, the wheels could have dug in or locked by sand being trapped by the wheel pants. This could have led to the aircraft flipping over to its back.Read more
CanadaOntarioEar Falls50°57’28” N 93°17’9” W
June 12, 2017 in Canada ⋅ ⛅ 19 °C
I wrote the first part of this based on my memory. I had no pictures. At the current date, August 17, I have received pictures from the crash site. Instead of simply editing my earlier report with real data, I am adding pictures as well as appending a section describing things as they really happened. In addition to being able detail more fully what happened, it turns out I can be a crappy witness about some things.
Doors consist of full glazing with a frame surround . Glazing disintegrated on impact. Body impact felt on left lower leg and forehead.
Soon as I stopped, I released my safety belt and reached for the main power switch but could not find it. I saw and smelled fuel streaming from a fuel line break in the line from fuel valve to gascolator (Estimate only 50 ml max available since the wing valves were shutoff.) After a more frantic search I still failed to find that switch. I did notice the battery cutoff lever was hanging loose so knew there was no power active.
My left foot was not aligned with the rest of of leg. Still concerned about a fire developing, I dragged myself from cockpit which was simplified because entire glazing/door was gone and fuselage was lying on ground. Dragged about 15 feet from right door (pilot side) and downhill from plane. A conscious effort was made to maintain foot/leg orientation to avoid further damage. Then the adrenalin effect stopped and leg pain started. Stopped moving and rested with the foot lying downhill and in line with leg.
The twin engine aircraft arrived overhead. I waved as it circled a few times before leaving.
Literally, having nothing better to do, I examined the wreckage from my vantage point. Aircraft position was upright and horizontal, on its belly on the semi-soft sand surface facing uphill. The main landing gear appeared intact but located approximately 15 feet behind the tail. An impact trench was not evident. The firewall and forward part if the plane appeared to have cleanly separated and 5 feet forward of the rest of the the fuselage.
The lower fuselage shell of the front cockpit suffered extensive damage. The rest of the fuselage appeared intact except for one semi-circular crack behind the baggage area along the circumference. Door glazing was gone and the the windshield had major cracks and missing sections. The wings and empennage appeared intact.
I estimated between 100 and 200 feet of landing area remained before a wall of trees.Surface was semi-soft sandy soil with occasional depressions.
When I receive photos of the accident area next week I will post some here and update the narrative to reflect reality.
I estimate about forty minutes after the crunch the pain became more noticeable. I began to say, "Ok I am ready to be rescued". After a few recitations of my new mantra I heard the whop, whop, whop of a helicopter. It was a Ministry if Natural Resources helicopter. The first of the crew arrived and jauntily announced, "We're first aid". Good. I needed first aid.
They splinted my leg with a cut sapling and electrical tape (no duct tape apparently) then hauled me to the helicopter which took me to the Red Lake hospital. The smooth landing was noticed. Rub it in.
Many X-rays of many parts were taken. I began to wonder if a more politically correct term could be used when dealing with a patient named Ray with unknown injuries. It just does not set the right frame of mind. Radiograph could be more appropriate.
After radiating me, pulling my broken tibia back into line, splinting me and cathetering me (most unpleasant), I got medivaced by Pilatus aircraft to Thunder Bay. The smooth landing was noted.
I arrived at Thunder Bay hospital around 11 pm Monday night, was operated on Tuesday morning and discharged from the hospital Friday morning. I left with a titanium tube in my left tibia and a pair of crutches. My fibula broke too, in multiple locations, but apparently it is left to reconnect itself in these situations.
Barb, my wife, arrived Wednesday pm. She stayed, then we stayed at the nearby Days Inn until the one week post-op observation and redressing. That happened Monday morning. Although Barb had rented a car, tourist opportunities were hampered by my inability to remain vertical except for short periods.
We flew back to Fredericton on Tuesday. That involved two aircraft with a stopover in Toronto. I noted the landings were not the greasers of either the helicopter or the medivac plane. But they were much smoother than my lawn dart technique by Primok Lake.
**** NEW SECTION BASED ON PHOTOS ******
The attached photos were taken by members of the Ministry of Natural Resources who administered first aid and then helicoptered my to Red Lake Airport. The areal view was taken from the helicopter before it landed.
From the tracking log on the aircraft and the data recorded with the first photo, my waiting time was approximately 25 minutes before the helicopter arrived.
The other views are from the left side. Its damage was much more severe than the right. I am not including a right side view since all I have were taken after the baggage area contents had been strewn about to gain access to the Emergency Locator Transmitter.
The second photo indicates I landed adjacent to line of boulders on the left. These were not visible from the right. The first time I noticed the boulders was when I saw the photos.
The third pic focuses on the area around the left side of the fuselage. Although there is an indentation in the sand from the rear fuselage and tailwheel, there is no trench. Apparently the plane impacted the grounded, ceased all forward motion and crumpled in place. The aircraft tail impacted, bounced up while the aircraft yawed slightly to the left before the tail dropping to the ground at its final resting position.Read more
CanadaOntarioEar Falls51°0’13” N 93°14’15” W
June 12, 2017 in Canada ⋅ ⛅ 19 °C
This report covers the period from recognition of the stopped engine to impact. I have always been interested in reading other accident reports, trying to glean anything that could learn to help me if faced with a similar situation. Evidently it is my turn to supply a case.
I have noticed two general types of pilots: those who say "the engine does not know if it is over water" when discussing crossing water and those who believe in Murphy's Law " If anything than can go wrong it will go wrong". I fall into the latter group so have been concerned with how to react in various emergency situations.
One's reaction to a situation is affected by one's background. I am a classic nerdy engineer who approaches everything with that mindset. Much of my career has been spent either designing things to work better or in quality assurance trying to determine why and how things can fail and to make them better. Because of a software background I often find it useful to think of the mind as a limited resource computer trying to share one mind with several tasks
Another significant aspect for this case is that my initial flying was in gliders. I became fanatical and got heavily involved in teaching gliding. At one time I was chief flying instructor for my club.
For this incident there is an additional opportunity as a learning tool. My instruments recorded a breadcrumb file containing position, speed and heading at one second intervals. With confidence I can say there are 3 aspects of looking at emergency: how I planned my actions, how I thought I performed my actions, and what actions actually happened. All were different.
In this note, a few notations have been adopted. Occasionally a quote would come to mind. Where not specified, I was remembering a line I said somewhere in the past. Ponderings made after the fact are within angle brackets <>.
Abandoned engine restart attempts, and recognized I had to shift to forced landing mode. Set aircraft speed to 75 knot and zero flaps for (near) maximum glide range. Established a mental mode where part of me tried to deal with the emergency directly, another 'observer task' tried to assess the quality of the decisions made and be on the alert for panic. I decided to make choices based on which way required the least finesse and precision: adrenalin would degrade skill and lead to excessive control motions.
Called Red Lake radio and declared an emergency. A nearby twin aircraft told the operator that they would look for me. The observer in me noted that after taking the initial parameters from me, he never contacted me directly although frequently talking with the twin. I was impressed: he was not trying to divert my attention. The exception was at one point I decided he needed my coordinates so gave the GPS values to him. He requested clarification of the latitude.
<This brings up one serious error I made. My attention got diverted to listening to the radio and 'correcting' them when I felt they got my location wrong. I should have concentrated on Aviating the plane while Navigating to a good landing location not Communicating. This was an especially significant blunder for me since I am easily distracted by a radio. When driving a car in town I turn the radio off as it it distracts from my attention. Significant brain capacity was wasted by not turning the radio off. My observer task eventually noticed my foolishness and I managed to ignore the radio from that point.>
Places to land were either small diameter trees, logging roads and lakes. I decide I would make choices based on what would be the most easy approach to adjust if needed.
I immediately eliminated the single lane logging roads as possibly too narrow to negotiate: I did not want to catch a wing tip at speed. “Choose northern trees before water”, from a conversation with a bush pilot a few years ago. I was not experienced enough to judge the massiveness of those trees. Ultimately since the trees were big enough for logging roads, I would look for alternatives. Looked for wider logging road sections and found an offshoot that had an uphill grade into wind. Selected that. Would make a downwind/base/final circuit to land there.
Then I began to stare a the selected landing area. I noticed that the end of the area sloped up more sharply than I originally thought. Became fixated keeping it in constant view. Zombie mode (became totally consumed with its form, sucking down all my mental capacity, observer task getting no time to break in).
<This fixation might be similar to what happened when an airliner went into a swamp in the Everglades in 1972 while the crew fixated on trying to understand why a minor alarm light was on.>
Finally noticed tree tops were closer to me than I wanted and that I had drifted too close to the landing site for a proper circuit pattern. I was amazed and annoyed I had fallen for the newby error of setting up a circuit to close the field. This was a big deal for me since from my gliding instruction days it had become almost a prime directive to “Watch the attitide (angles) to the flare point. Started to ponder how I had become so inept. Promised to practice circuits after the trip. Zombie mode. Found myself having finished both a base and final turn and was now lined up on final. These were not conscious decisions but mechanical motions that I knew had to be made. It was very steep angle to the threshold of the field. The far end was at a more reasonable angle to meet. Perhaps my earlier fixation with the hill at the far end had either affected where I should turn to base or I just made a base and final turn automatically without thinking. “Make good turns in the circuit” i.e. looking out of front for good attitude/speed control and coordination. I don't remember the turns at all but suspect they were well executed... just in the wrong place.
Angle judged too steep to land in the space available. Contemplated full spoilers with side slip vs a figure 8 S turn. Rejected the full spoilers because if that was insufficient there would be no room for another maneuver.
Also a steep turn figure 8 was a common practice maneuver I made when working on coordination and speed control. In fact, during the flight previous to starting on my trip, I performed some to evaluate and hone my skills.
Began my S turn to the right. I estimated I got about 45 degrees beyond a right angle (135 degrees) when “Don't turn away from the field” was remembered form an instructor while practicing forced approaches. Banked left to form the right hand loop. Zombie mode. Noticed speed had dropped 10 knots on asi. “Tweak stick forward to reduce angle of attack” from my instructing days. I was half way through the the left hand loop and was over trees with the field at at a shallow angle. Straightened the bank and took the shortest distance to the clearing. Zombie mode.
I mentally heard, “Cleared the trees now let see where I can land. Oh, I'm here”. The observer noted the words which were of a common thought when clearing trees to get into a small field. There was probably a fixation on clearing the tree tops. The aircraft altitude was below the flare point. Impact was imminent. "Freeze the stick”. Was concerned about a panic jerk back of the stick so locked stick in current position. The thought would have been fortified by the instructing tip of freezing the stick after ballooning or bouncing while landing to let the aircraft settle is almost always a safe response.
Impact. The observer was back noting the behaviour of the aircraft during the crash particularly windshield destruction.
The attached image is the final two and a half minutes of the breadcrumb trail. The little hook at the end should be ignored as an artifact of the gps coordinates becoming more accurate while being stationary. The landing site differs significantly from when the aerial photography was done. The terrain is semi-soft sand surrounded by a trees and a few more logging roads.
Note my attempted S turn near the top. The admonition to not turn away from the field did not happen at 135 degrees. It was 45 degrees. The intent was for the S turn to not consume much landing length. Because it was so skewed, final touchdown was at the far end area, perhaps less than 200 ft remaining. Fortunately (?) I had zero rollout,
By the way, if you look are trying to find the impact point from my Inreach track (https://share.garmin.com/RayStl), the final point is at the Red Lake hospital. that was where my Inreach satellite device was returned to me and I shut it off. Impact point was further east, just south of Little Trout Lake at the point labelled 4:22 pm on June 12. That is Atlantic time while the impact point was in the Central Time zone.Read more
CanadaOntarioEar Falls50°58’56” N 93°13’39” W June 12, 2017 in Canada ⋅ ⛅ 19 °C
The crash will be discussed in five parts. The first is the occurrence of the failure that necessitated the emergency landing, the second is the sequence of events and thought processes that happened from there to the point of impact, the third is the results of the impact and the fourth covers hindsight and what might have happened if I I had behaved flawlessly (that was the toughest to write) , and the fifth has musings and a revelation that came out of the accident.
This is Part 1.
This was to be a trip from Armstrong Airport (CYYW) to Red Lake Airport (CYRL) with an estimated airtime of one hour 55 minutes.
Recall I had a propeller vibration issue theorized to be from the development of irregularities in the paint along the leading edge of the prop blades. The only tools and supplies locally available to smooth the blade profile were 400 grit sandpaper, rags and Varsol from the local store, Scotchbrite, water, gasoline and a sanding pad from Art, the local who happened to become my chauffeur and local knowledge source. Acetone or any other strong solvent was not available. Neither Varsol or gasoline had any effect on the paint.
Very careful wet sanding with first the sandpaper and then the Scotchbrite worked surprisingly well. I 'finished' my handiwork with some spray wax I carry when I travel.
Flight test results were good. When I landed it was already 12:40. After adding another 20 L of mogas donated by Art, what a nice guy, I was finally able to start my flying day... what was left of it.
But not yet. To get at the spray wax I had to unload most of the baggage compartment. By the time it was all repacked it was 1:15. I was itchng to go.
But not yet. I was hot, hungry, thirsty and antsy. Part of me realized that I needed to calm down and take a break. So I drank some water, ate some figs, added nitrogen to the local soil. I rested a few minutes before departing around 1:35 pm in a more relaxed state. A calm initial state helps in understanding and responding to unusual conditions. Yup, I know what I am like when tired, not good at making decisions. I am glad I took the break.
I hoped the lack of vibration could be maintained, at least til my next destination. As the trip progressed, the vibration level felt was noted. It seemed normal and stable so I felt more relaxed as the destination approached. Height above ground was 4500 ASL, 3400 AGL by my GPS enabled device. I performed regular observations of the terrain for landing suitability... no change for awhile, treed with small diameter tees, narrow logging roads, lakes.
While about 10 minutes from the airport, I radioed position and intent to the airport radio operator. I noted wind conditions and the active runway was 26.
When returning my eyes to the front after a side scan I noticed the propeller was stopped vertically in a feathered position. I did not notice the absence of sound until a few seconds later.
I was puzzled by the lack of fuel engine effects and that the propeller was feathered. The right tank was in use. Fuel level is measured directly by a sight tube in each wing. Fuel valves are near each fuel gauge. I immediately turned the fuel valve on for the left tank noting it showed approximately 15 L remaining. Shifted to right side to turn its valve off then noted it also had about 15 L of full so turned the valve back on.
Although part of me was aware that you should not start an engine with feathered prop, I pressed starter button anyway. No blade movement.
I reflexively reached for the feathering pitch control and started to move it by beginning to pull. Then I noticed it was already in the normal, not feathered, position and pushed it back. I don't recall feeling any resistance to moving the control either way but might not have been in a frame of mind to notice.
To myself, “I can't fix this.”Read more
CanadaOntarioEar Falls51°0’11” N 93°15’13” W June 12, 2017 in Canada ⋅ ⛅ 19 °C
End of GUFY tripping. Not my best landing. Sorry for the delay in reporting. Just got released from Thunder Bay Hospital. While GUFY is essentially totaled, the only major injury to me was a broken left leg, the tibia above the ankle. Fortunately there is a procedure where they insert a titanium 'rod' down the soft center of the bone and screw it in place. The leg is instantly weight bearing. A couple of days later I was ready to leave the hospital without any cast but some crutches. Due to an administrative confusion I finally got to leave Friday morning.
The staples come out in a couple of weeks and they say in a month I will be back to 'normal'. Could have been worse.
I will give some details of the accident (it was not on purpose). But first I will address the elephant in the room. No I am not heartbroken because I have lost my beloved plane.
When I first got the plane, I set the goal of visiting all the provinces in Canada. I did that in 2013. Everything since then has been a bonus. I am happy and grateful for them all but have always been aware that some day I would have to stop. The most likely reason was "losing my medical" due to advancing age. That is why I have been so vigorous in pursuing these voyages regularly. Literally, it was fun while it lasted.
I have been aware of the risks inherent by my flying trips, with the understanding that the aircraft could be destroyed under certain circumstances. That was acceptable to me for the increased benefits from these voyages. On the other hand, I was not prepared to accept any significant increase in risk to anyone's life, including mine. I always said I would trash the plane to save a life. I did what I could to keep the plane as reliable and decided the worse acceptable case was to crash somewhere where it would take a couple days for rescue. I instrumented my plane and survival equipment accordingly. A serious but reparable injury was acceptable. In effect, I have already gone through potential anguish of losing the plane and considered the physical and mental pain acceptable.
As it turned out, the crash was quite close the outside limit of my acceptability, Rescue arrived in less than an hour. I was ready.
I would have rather sold the plane due to advancing decrepitude then adding to the landscape of northern Ontario, but evidently a very small risk is still not zero. Bit like winning the negative lottery.
I will write another note on what led up to the accident. For now I will just state that while approaching Red Lake airport around 2:30 pm local time the engine suddenly stopped with the prop pitch in feathered mode. The terrain was wooded with numerous small lakes and some logging roads.
A number of people, especially non pilots, heard the story of my accident and remarked that I was lucky to have survived. I disagree with that sentiment. It implies that flying is an inherently risky activity where mishaps tend to lead to fatalities. Not true. It is true that serious mishaps, although relatively rare, when they do happen tend to result in serious vehicle damage. But pilots are trained to handle these emergency conditions and respond accordingly to maximize the likelihood of survival. It is not a matter of luck, or great skill, but training. Or at least that is the way is is supposed to work, and did in this time too.
As a former glider pilot/fanatic, it took me a long time to trust the engine enough not to fear that it could fail at any time, so always kept within range of a good landing spot. Ironically an engine stoppage was involved in the destruction of my plane.Read more
CanadaOntarioThunder Bay DistrictArmstrong Airport50°17’43” N 88°54’36” W June 12, 2017 in Canada ⋅ ⛅ 10 °C
The Pipistrel prop is a hollow carbon composite design. Very light, very fragile. Its surface is protected by paint not a gel coat.
The bad news is that the leading edge can get nicked easily by small gravel bits. The good news is that small surface effects can be easily repaired.
The year I visited all the territories in Canada I had to use many gravel strips. After returning south to visit my Alberta brother, the prop looked like its leading edge had been sandblasted. After a bit of epoxy filling of some chunks, sanding and some paint, the prop was backto its old self.
When they started using leading edge protective tape, most of this necessary maintenance ended.
I will take before and after photos of the prop before I attempt maintenance.
After removing the gnarly paint surface and getting to the smooth base, I will use spray wax to give it a modicum of protection from UV and flying crudlets. I carry that with me and use it every few hours on the surface of the wings and prop to minimize bug bits sticking. After reaching Alberta I will do a 'proper' leading edge repairRead more
CanadaOntarioThunder Bay DistrictArmstrong Airport50°17’43” N 88°54’36” W June 11, 2017 in Canada ⋅ 🌧 14 °C
Oops, again.
As I got further away from Nakina the vibration returned. It got worse. I decided to shorten the trip to Armstrong. It got worse.
When I landed the paint on the leading edge of the prop showed many corrugations. I am not sure if the paint swell and buckled or they were just lines of erosion.
Plan B: get something like acetone and strip away all the paint from the leading edge. Then fly naked to Alberta. At my brother's I will get some supplies to prep the surface, repaint an sand the surface 'properly.
Unfortunately the Armstrong store does not open until 10 am. It is unlikely I would be able to leave before noon... assuming all goes well. It is not feasible to make it all the way to Drayton Valley.
The latest plan, for what it's worth, Red Lake ON then Swan River MB.
The Armstrong airport is quite far from from Armstrong... or anything actually. Ther was no one at the airport and everything was locked up, Cell phones do not work, but they do in downvillage Armstrong.
I was at the airport for over a half hour, discovering there were zero facilities available. No vehicles past on the road although two freight trains rumbled by. The plane was tied down and my cart loaded for the 1 hour plus walk to town when a pickup truck passed by. I waved to hom and he stopped. Then he drove me to town, gave me a tour recommended a motel and restaurant. He said to call him tomorrow for the ride back to the airport...since there are no taxis.Read more
