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Old 12-22-2015, 12:46 PM   #61  
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Yes, this case is under litigation and the loss of engine power from failure of the of the power turbine wheels is irrefutable. The compression turbine wheel was intact.

Gravity will cause acceleration of an object as it falls. This is basic physics. Maybe this caused the acceleration before impact?

(In physics, gravitational acceleration is the acceleration on an object caused by force of gravitation. Neglecting friction such as air resistance, all small bodies accelerate in a gravitational field at the same rate relative to the center of mass.[1] This equality is true regardless of the masses or compositions of the bodies.
At different points on Earth, objects fall with an acceleration between 9.78 and 9.83 m/s2 depending on altitude and latitude, with a conventional standard value of exactly 9.80665 m/s2 (approximately 32.174 ft/s2). Objects with low densities do not accelerate as rapidly due to buoyancy and air resistance.)

I'm just trying to make sense of this..... Any help is appreciated.
Gravity causes a downward acceleration, not a forward one. A high rate of speed straight down would imply either a stall, (extremely low forward speed), spin, or abrupt nose down pitch. In all of these cases, the wreckage would be constrained to a rather small area, which is not consistent with the wreckage path as described in the narrative. The investigators will look not only at the tops of the trees along the impact path, the length of the debris field, but also how the parts of the aircraft failed, as a high rate of speed impact in a forward direction has many characteristic signatures.

When an aircraft is climbing, it is at a high angle of attack, creating significant drag, if one is to suddenly fail the engine, the airspeed drops fast, in nearly every case where someone is not expecting this to happen, a significant loss of airspeed is to be expected, if the pilot is proficient, this can usually be quickly recovered, but at only 260', it's going to be difficult to get the speed back to around 90 (close to best glide speed for a caravan) before reaching the ground level. Enough control should be able to be maintained to choose a flight path, but this can be much easier in training environments when you are expecting it rather than when out in the industry "on the job". This sudden loss of airspeed is one of the primary reasons why most instructors reinforce not turning back towards the airport, at least until significant altitude is achieved, as your aircraft is simply in too low of an energy state to be attempting a turn without stalling/spinning or reaching the ground even earlier.

The glide distances and capabilities are not unknown, using the lift coefficient of the wing design and other factors, it can be calculated what the maximum glide distance of the aircraft would be at 260'. If the pilot chose to push the nose down and accelerate to a faster speed, the aircraft would not glide as far. If power was present, the aircraft would be able to glide further and/or maintain a totally different glide path. As I mentioned before, extensive modeling and simulation is used to determine this.

It is not surprising that the PT6 centrifugal compressor wheel (this is what you mean, correct?) remained intact, that's one of the stoutest parts of the engine/aircraft, usually a pretty big/thick chunk of metal. One thing to remember is that any turbine engine is spinning at massive RPMs, so when a catastrophic event is introduced, it's going to tear itself apart. As you may be indicating, the key is to determine if this was casual or a result of other damage.
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Old 12-24-2015, 05:48 AM   #62  
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Thanks JNB, Yes, the investigator said the inside of the engine was completely demolished. The compressor wheel, only inches away from the power turbine, was intact meaning the impact did not cause the damage to the power turbine wheel. The inside of the exhaust was riddled with pings from the inside out as the pieces of broken turbine were extruded through it. He said there was no "kink" in any part of the power portion or linkage (not sure I am saying that correctly) of the engine as would be expected if the engine was running and then suddenly stopped on impact. The investigator said it is "textbook 101 power turbine wheel failure" This had to have a major impact on the takeoff. Whether my son got frantic and made mistakes after that remains to be seen. We may never know. All I know is that he was a good pilot and I was so proud of him. I wanted to learn more about what happened and I have. Thank you everyone and I will let you know what transpires in the future with the litigation. I admire you pilots and wish you safe flying.
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Old 12-26-2015, 05:52 AM   #63  
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I think the key to this NTSB narrative is that my son immediately banked to the right after takeoff, which was westward when he was supposed to be headed south. I believe he felt something was wrong with the engine but still had power to accelerate throughout the 58 second flight. Since he had power, he made the right bank and continued to accelerate to over 150 kts. At some point on that bank, the engine completely lost power and he tried to keep his pitch up but was only able to get to negative 2 degrees. His forward motion continued as he took off the tops of trees and then impacted the trunk of a tree. I went to the crash site and saw the tree. It was a large hardwood tree that he broke in half and completely uprooted the trunk. The aircraft then turned on its side and wrapped around 2 other trees. My son was thrown through the roof and landed about 10 yards ahead. The engine landed on top of him. My lawyer was able to get the police photos and one shows his foot sticking out from under the engine and rubble. It's a terrible site that haunts me. It was pitch black that night so he had to be watching his instruments and would have known the attitude of the aircraft. I'm sure he tried as hard as he could to complete the turnaround.
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Old 01-03-2016, 05:51 PM   #64  
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BW, I'm very sorry to hear about the loss of your friend.

It always feels like a hammer when the loss is someone we knew.

NP
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Old 01-07-2016, 09:53 AM   #65  
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I have to ask - you keep mentioning words like "irrefutable", "discovery" and "investigator" - yet you mention you have not been given an opportunity to inspect the engine.

So - who told you what about the engine condition?

Just like James tried to explain, the trajectory fully supports NTSB's findings, we would all like to hear more where you heard about this "power turbine wheel" failure?

Also, you say "Since he had power, he made the right bank and continued to accelerate to over 150 kts. At some point on that bank, the engine completely lost power and he tried to keep his pitch up but was only able to get to negative 2 degrees." - this is completely implausible. At 150kts you have a massive amount excess energy you can convert to altitude. I'm not a Caravan pilot, but I assume you can gain 300-400ft easily before stalling. This too supports the fact, that engine was fully functional until the impact.
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Old 01-08-2016, 06:36 AM   #66  
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I have to ask - you keep mentioning words like "irrefutable", "discovery" and "investigator" - yet you mention you have not been given an opportunity to inspect the engine.

So - who told you what about the engine condition?

Just like James tried to explain, the trajectory fully supports NTSB's findings, we would all like to hear more where you heard about this "power turbine wheel" failure?

Also, you say "Since he had power, he made the right bank and continued to accelerate to over 150 kts. At some point on that bank, the engine completely lost power and he tried to keep his pitch up but was only able to get to negative 2 degrees." - this is completely implausible. At 150kts you have a massive amount excess energy you can convert to altitude. I'm not a Caravan pilot, but I assume you can gain 300-400ft easily before stalling. This too supports the fact, that engine was fully functional until the impact.
I think it's natural for a parent to try to understand how their child died. And I think it's natural for a parent who felt his child was very good at something to have a hard time accepting the possibly the child made a mistake. I know if we were talking about my kids that's how I would feel.

So you have a parent trying to understand a tragedy, and an attorney sees an opportunity to dip into some deep pockets. It's no surprise that he would tell the father that the son is blameless and that the fault lies with a large company. It's not hard to understand why the father wants to believe what the attorney is telling him (confirmation bias, which we all had to learn about when we did our instrument, commercial, and ATP ratings).

Don't be hard on the dad. He's going through something terrible beyond words. Try to understand the big picture. And if you must be cross with somebody, direct your hard feelings at the attorney who is taking advantage of the father's emotions.

[In the spirit of full disclosure, there are four attorneys in my immediate family, and I'm not a Pavlovian attorney-hater.]
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Old 01-17-2016, 09:32 AM   #67  
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Dera,
We were initially denied access to the wreckage by Martinaire's attorneys without a court order. My aviation attorney has never been in such a situation where he had so many obstacles in his discovery. We got the court order and an investigator from Aeroscope discovered that the turbine wheel failed. It was "textbook 101" findings in his words. An aviation expert investigator, looking at the engine log book, learned that turbine wheel was hot inspected or taken out and reassembled by Martinaire in Lansing a few weeks before my son's accident. That turbine wheel should have lasted for another 1800 hours. Instead, it lasted 30 hours. If that turbine wheel is not perfectly balanced, it is going to fail. I'm not a pilot or an aircraft mechanic. I'm just trying to understand what happened. I ORIGINALLY believed the NTSB report that my son got SD so I don't have a problem accepting the possibility that my son made a mistake. My wife did not buy it. The wording about the -2 degrees pitch is from the NTSB narrative which neatly explains THEIR conclusion of a normally operating engine. So yes, a pilot like yourself is going to think it makes sense and we can move on. Someone lied in the report that the engine was normal on inspection and the company that did the inspection was Pratt Whitney. I know that engine failed for a fact and I believe Martinaire is at fault.

As far as the attorney taking advantage of my emotions, that is not the case. He is working off of a percentage of collection, if any. He is not going to put his money into this investigation if he thought we didn't have a chance of finding a party at fault. The problem is that it comes down to workers' comp law protects Martinaire from being sued by an employee. In this case, it is my son's estate with me acting as administrator. So although we believe they are at fault, they are protected by those laws. My attorney has recommended that we drop the lawsuit. Martinaire will just hire a new pilot and continue in their same old ways. Just hope that if your son or daughter fulfills their dream of becoming a pilot, he or she doesn't work for such a company.

This system of the NTSB choosing whomever they want to help them investigate is faulty. I understand they are undermanned. There have been articles and television reports about this conflict of interest in their investigations. My lawyer tried to sue the NTSB 20 years ago on this item, but the lawsuit was thrown out because they make their own rules and they can ask any source to help them with their investigation. Even if it is the manufacturer of the engine that may have failed.

I want to thank everyone for their input. Be safe. Special thanks to Panzon for understanding my quest for the truth.
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Old 01-17-2016, 09:54 AM   #68  
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Dera,
We were initially denied access to the wreckage by Martinaire's attorneys without a court order. My aviation attorney has never been in such a situation where he had so many obstacles in his discovery. We got the court order and an investigator from Aeroscope discovered that the turbine wheel failed. It was "textbook 101" findings in his words. An aviation expert investigator, looking at the engine log book, learned that turbine wheel was hot inspected or taken out and reassembled by Martinaire in Lansing a few weeks before my son's accident. That turbine wheel should have lasted for another 1800 hours. Instead, it lasted 30 hours. If that turbine wheel is not perfectly balanced, it is going to fail. I'm not a pilot or an aircraft mechanic. I'm just trying to understand what happened. I ORIGINALLY believed the NTSB report that my son got SD so I don't have a problem accepting the possibility that my son made a mistake. My wife did not buy it. The wording about the -2 degrees pitch is from the NTSB narrative which neatly explains THEIR conclusion of a normally operating engine. So yes, a pilot like yourself is going to think it makes sense and we can move on. Someone lied in the report that the engine was normal on inspection and the company that did the inspection was Pratt Whitney. I know that engine failed for a fact and I believe Martinaire is at fault.

As far as the attorney taking advantage of my emotions, that is not the case. He is working off of a percentage of collection, if any. He is not going to put his money into this investigation if he thought we didn't have a chance of finding a party at fault. The problem is that it comes down to workers' comp law protects Martinaire from being sued by an employee. In this case, it is my son's estate with me acting as administrator. So although we believe they are at fault, they are protected by those laws. My attorney has recommended that we drop the lawsuit. Martinaire will just hire a new pilot and continue in their same old ways. Just hope that if your son or daughter fulfills their dream of becoming a pilot, he or she doesn't work for such a company.

This system of the NTSB choosing whomever they want to help them investigate is faulty. I understand they are undermanned. There have been articles and television reports about this conflict of interest in their investigations. My lawyer tried to sue the NTSB 20 years ago on this item, but the lawsuit was thrown out because they make their own rules and they can ask any source to help them with their investigation. Even if it is the manufacturer of the engine that may have failed.

I want to thank everyone for their input. Be safe. Special thanks to Panzon for understanding my quest for the truth.
The NTSB is the world's leading accident investigative organization.
What conflict of interest are you actually pointing too regarding a C-208 mishap with Martainaire?

Sometimes the truth can hard to accept.
I hope you are able to deal with this tragedy in the future.
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Old 01-17-2016, 10:26 AM   #69  
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I agree, the NTSB has operated in such a way that Conflicts of Interest are almost impossible. I have lost several good friends to aircraft crashes, all but 1 of them died as a result of "pilot error."

Recently the NTSB faulted both the crew and ATC in crash that killed a former coworker of mine. In my opinion and experience, if they have to make the "hard calls" they do. I just can't see the NTSB getting into coverups and mistruths. So sorry for your loss.

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Old 01-17-2016, 07:01 PM   #70  
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As far as the attorney taking advantage of my emotions, that is not the case. He is working off of a percentage of collection, if any. He is not going to put his money into this investigation if he thought we didn't have a chance of finding a party at fault.
The sad part about this is I know of several cases where the manufacturers have settled rather than fight, even though they were right, just due to the costs of dragging it all out. It becomes a poker game of "how much money do you have to throw at this case".
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