Why Lycoming engines cost so much

[N801BH]

Sir. I commend you on being up to speed on joint sealing and the whole concept of clamping forces. I am impressed. My gut feeling is the plaintiffs attorneys and their expert witnesses were able to convince the jury that this "stack up" was the main reason the motor failed and Teledyne was the bad guy.. I also feel that the Teledyne legal team was sleeping at the switch because that type of failure has happened on engines that have never been into, been overhauled or have ever had any gasketmaker, sealent or any other product used to coat the o-rings that could possibly migrate into the cylinder flange to case joint and cause "stack up". That point alone, properly driven home to the jury should have been able for them to neutralize the plaintiffs claim of the "stack up" failure scenerio.. Just my opinion though.

Also there is alot of thermal dynamics involved here between the case, which is aluminum, and the cylinder flanges that mate to it, which are steel and the expansion rates of the two dissimilar metals is quite the challange to keep sealed. This expansion/contraction at differing rates contribute to fastener loosening too.

I enjoy debating smart people on topics like this so thanks for the mental workout.

Tailwinds,
Ben.

 

[hindsight2020]

tort reform anybody?

Punitive damages reform to be exact. Actual malice "trigger" measures, et al, would go a long way towards re-balancing the economic havoc this legal free-for-all creates for the rest of society who would like to enjoy the benefit of activities and use of goods without making it prohibitive for the majority.

Remove the cheese from the kitchen, the rats disappear.....Proffering band-aid solutions like asserting "well, appeals draw down actual settlements..sometimes" does little to cure the disease. What a whipsaw this country has turned to. Nobody wants to be responsible for anything and business can't be trusted farther than you can throw them....

 

[MoveLikeNight]

Was not there yet, but on crashing or during an emergency landing I would likely cut the power( idle RPM 550 rpm on mine) to lessen the impact. Did the investigators find the throttle fire walled or at idle?

Neither side made any reference to that, actually, so I unfortunately can't answer. The plaintiff showed the tach as evidence of engine failure and the defense pretended it didn't exist at all except for in cross where one of their witnesses claimed the needle seemed to be pointing above the 10 rather than at the 5. Lycoming's lawyers never asked or said anything about it at all.

It is an interesting point.

 

[weilke]

I can see how a jury would buy that narrative.

 

[jesse]

For the uneducated, me, how exactly can they determine if the stall light was on before the crash?

I've seen gasket maker used on a lot of engines, and have done so myself, I sure the hell haven't seen it start loosening up the bolts in the middle of the night. The only time I've had a part fall of an engine was when I forgot to torque it down. I suppose I could blame that on gasket maker and sue Suzuki (since it is recommended in their service manual).

 

[MoveLikeNight]

For the uneducated, me, how exactly can they determine if the stall light was on before the crash?

By examining the filament. It's never a 100% for sure test, but it usually works decently. They do the same things for headlights in cars for auto-accidents.

If a filament is hot (on) at the time of impact, it can bend in the direction of impact. If it is cold (off), it can break or shatter due to being inflexible.

You can also check for oxidation. The bulb would have to break so the hot filament would get hit by cold air. Same scenario, but if the glass shatters the filament can catch small pieces of glass and fuse together.

They didn't mention exactly what they discovered other than no evidence that the light had been on.

 

[jesse]

By examining the filament. It's never a 100% for sure test, but it usually works decently. They do the same things for headlights in cars for auto-accidents.

If a filament is hot (on) at the time of impact, it can bend in the direction of impact. If it is cold (off), it can break or shatter due to being inflexible.

You can also check for oxidation. The bulb would have to break so the hot filament would get hit by cold air. Same scenario, but if the glass shatters the filament can catch small pieces of glass and fuse together.

They didn't mention exactly what they discovered other than no evidence that the light had been on.

Interesting. Makes sense, but a completely imperfect solution. I'd personally have a hard time accepting that into my decision making process.

 

[MoveLikeNight]

Interesting. Makes sense, but a completely imperfect solution. I'd personally have a hard time accepting that into my decision making process.

I agree. I knew of the methods of filament testing before hand, so I didn't treat it as an undeniable fact.

 

[AuntPeggy]

I'm just now reading the NTSB report.

The propeller blades exhibited both chordwise and spanwise scoring, and also exhibited some "s-bending." The propeller flange was fractured, and the propeller axis was oriented along the left side of engine. Rotational marks were found on the starter housing, and the crankshaft flange was also bent.

Sounds like the engine was turning the propeller.

According to the surviving passenger, the airplane departed Wittman Regional Airport (OSH), Oshkosh, Wisconsin, earlier that same day, and landed at Youngstown to refuel. An employee at the airfield stated that during the refueling, he filled the main fuel tanks. He noticed that while the airplane was on the ramp, the tail was almost touching the ground, and that the airplane "was nose high." After takeoff, he saw that the airplane "was having a hard time climbing out, and [it] was hanging on the prop and mushing its way out. I saw [the airplane] take off, make a 180-degree turn to enter the downwind, and lost sight of him."

Makes it sound like he was overweight or out of balance, but NTSB figures he was just barely inside the envelope.

The electric fuel pump switch was in the "off" position, and the carburetor heat control was destroyed."

Admittedly I haven't flown a Piper in many years -- shouldn't the electric fuel pump be on during takeoff?

 

[EdFred]

Admittedly I haven't flown a Piper in many years -- shouldn't the electric fuel pump be on during takeoff?

It depends.

 

[MoveLikeNight]

I'm just now reading the NTSB report.

Sounds like the engine was turning the propeller.

The propeller did have scoring and one of the blades was slightly bent, but it looked nothing like the pictures they showed us of propellers at power when they hit the ground. The pictures were out of aircraft investigation manuals rather than hand picked plaintiff photos. The scoring and scratching looked like what I would expect something hitting the ground would. It didn't look to have a lot of extra force behind it other than the speed of the plane and windmilling.

Makes it sound like he was overweight or out of balance, but NTSB figures he was just barely inside the envelope.

The model of plane (Cherokee 6) tends to sit nose high on the ground due to the front wheel strut. They can sit nose high on the ground if the front wheel strut doesn't collapse/retract (not sure of the terms).

No one had reports of the plane being overweight or off balance except for one investigator hired years after the accident by Lycoming. His testimony was all based off of reading other reports and drawing his own conclusions. There were also weight discrepancies. He claimed some passengers were almost 50 lbs heavier. He included 2lb extra per piston since they were from Superior and another component or two. He didn't account for his additional engine weight in center of gravity calculations. So his final numbers had the plane like 350 lbs overweight and off center of gravity.

The airfield employees testimony was done via video, so the cross wasn't as extensive. He did also claim that the engine sounded like it wasn't producing full power. I'm afraid I don't know what mushing is.

Admittedly I haven't flown a Piper in many years -- shouldn't the electric fuel pump be on during takeoff?

My memory is getting a bit off as time passes, but I believe in the in-air emergency check list for loss of engine power, one of the steps was to try to reset the fuel system by turning off pumps and switching tanks. I don't remember anyone talking about the fuel pump's status though. So other than a speculative "maybe he was trying that", I can't offer anything here.

 

[jesse]

Makes it sound like he was overweight or out of balance, but NTSB figures he was just barely inside the envelope.

I've seen MANY Piper low wings with not a passenger in the airplane that have a tail nearly touching the ground. Not sure what it is but it seems like nose strut issues seem more common on them than Cessna aircraft.

 

[EdFred]

I've seen MANY Piper low wings with not a passenger in the airplane that have a tail nearly touching the ground. Not sure what it is but it seems like nose strut issues seem more common on them than Cessna aircraft.

We don't slam the nose down on landing like the Cessna drivers. Higher skillset, higher nose travel.

 

[JeffDG]

By examining the filament. It's never a 100% for sure test, but it usually works decently. They do the same things for headlights in cars for auto-accidents.

If a filament is hot (on) at the time of impact, it can bend in the direction of impact. If it is cold (off), it can break or shatter due to being inflexible.

You can also check for oxidation. The bulb would have to break so the hot filament would get hit by cold air. Same scenario, but if the glass shatters the filament can catch small pieces of glass and fuse together.

They didn't mention exactly what they discovered other than no evidence that the light had been on.

Hmmm...that presumes that a stall condition exists at the time of impact. If a plane stalls at low altitude and you get a break, the stall is done, but you could still not be able to recover within the altitude available.

 

[MoveLikeNight]

Hmmm...that presumes that a stall condition exists at the time of impact. If a plane stalls at low altitude and you get a break, the stall is done, but you could still not be able to recover within the altitude available.

True. The defense claimed however that he stalled, his wing dropped, and hit the ground pretty much immediately. The plaintiff contest that he at this point realized he wouldn't make the run way, so did a slide to put the plane down in the field before he hit the trees.