Mooney down in Tampa Bay. No injuries

[chriscalandro]

Correcting a lie and embellishment is NOT “making an impassioned case”

[EricJ]

2 hours ago, Shadrach said:

Here ya go, to simplify:

A process requires torque seal to be applied after torque is applied.     There are four possible outcomes.

1.   Torque is applied, and torque seal is applied.
2.   Torque is not applied, and torque seal is applied.

3.  Torque is applied, and torque seal is not applied.

4.  Torque is not applied, and torque seal is not applied.

Three of these conditions, 2, 3, and 4, contain process failures.    The lack of torque seal is present in two of them, 3 and 4, but only one of those did not have torque applied.    Of the two cases where torque was not applied, 2 and 4, the lack of torque seal only coincides with one of them.

So torque seal isn't any better than flipping a coin at indicating the presence or absence of torque if all four condition have equal probability.    In any case, the presence or absence of torque seal is not a determining indicator of torque having been applied or not, regardless of the relative probability of each case.

It is, however, reliable at indicating whether the fastener has moved since application.   But it doesn't even do that unless somebody inspects it.

In this case it was not applied, and there's no indication it was inspected after the leak check.    So the use, or not, of torque seal seems pretty moot.   The absence of torque, however, seems evident. 

[Shadrach]

13 hours ago, EricJ said:

Here ya go, to simplify:

A process requires torque seal to be applied after torque is applied.     There are four possible outcomes.

1.   Torque is applied, and torque seal is applied.
2.   Torque is not applied, and torque seal is applied.

3.  Torque is applied, and torque seal is not applied.

4.  Torque is not applied, and torque seal is not applied.

Three of these conditions, 2, 3, and 4, contain process failures.    The lack of torque seal is present in two of them, 3 and 4, but only one of those did not have torque applied.    Of the two cases where torque was not applied, 2 and 4, the lack of torque seal only coincides with one of them.

So torque seal isn't any better than flipping a coin at indicating the presence or absence of torque if all four condition have equal probability.    In any case, the presence or absence of torque seal is not a determining indicator of torque having been applied or not, regardless of the relative probability of each case.

It is, however, reliable at indicating whether the fastener has moved since application.   But it doesn't even do that unless somebody inspects it.

In this case it was not applied, and there's no indication it was inspected after the leak check.    So the use, or not, of torque seal seems pretty moot.   The absence of torque, however, seems evident. 

I was not confused by your assertion, only the tenacity with which you demonstrate in denying my point. Here ya go. To simplify…

A shopping list requires that a check mark be applied to the list after an item is put in the cart.    There are four possible outcomes.

1.   The item is put in the cart, and the list is checked.
2.   The item is not put in the cart, and the list is checked.

3.  The item is not put in the cart, and the list is not checked.

4.  The item is put in the cart, and the list is not checked.

in this case the item was not purchased, so the use of a shopping list seems moot?

[EricJ]

1 minute ago, Shadrach said:

I was not confused by your assertion, only the tenacity with which you demonstrate in denying the correct point. Here ya go. To simplify…

A shopping list requires that a check mark be applied to the list after an item is put in the cart.    There are four possible outcomes.

1.   The item is put in the cart, and the list is checked.
2.   The item is not put in the cart, and the list is checked.

3.  The item is not put in the cart, and the list is not checked.

4.  The item is put in the cart, and the list is not checked.

in this case the item was not purchased, so the use of a shopping list seems moot. 

I've no idea what you're agreeing or disagreeing with.    We may be in violent agreement, or not, I can't tell.   You seemed to be indicating that torque seal could be useful to indicate that torque had been applied.   My assertion was just that the presence or absence of torque seal can't do that.   

Regardless, our tenacity is equal to this point, so I'm sure what that indicates, either.

[Shadrach]

25 minutes ago, EricJ said:

I've no idea what you're agreeing or disagreeing with.    We may be in violent agreement, or not, I can't tell.   You seemed to be indicating that torque seal could be useful to indicate that torque had been applied.   My assertion was just that the presence or absence of torque seal can't do that.   

Regardless, our tenacity is equal to this point, so I'm sure what that indicates, either.

I think it is context. My primary use of torque seal is as a visual verification that a fastener has been properly tightened/torqued. My assumption was that most people use it this way. The auto industry does. When I hung my engine, my IA insisted every nut bolt and hose be marked after torquing. I painted the fastener right after tightening. I think the process helps to avoid un-torqued fasteners. If the owner of the Money Uboat and his mechanic would have had such an agreement, I think it could have prevented this accident.

[Pinecone]

It will work if one is diligent about ONLY applying torque seal immediately after torquing.

[Fly Boomer]

1 hour ago, Pinecone said:

It will work if one is diligent about ONLY applying torque seal immediately after torquing.

Bingo!  @Pinecone has summarized this discussion in a single sentence.  You could also use a Post-It with a little diagram of the part you are working on, and put a check mark next to each fastener or B-nut or whatever as soon as you tighten it.  But using torque seal is a little handier.  The torque seal itself is indicative of nothing -- it COULD indicate that a fastener has moved, but that's probably not its primary use.  It's just a tool that a mechanic can use to keep track of what has been tightened and what has not.

[chriscalandro]

Even if the mark was applied, would the cowling have come off and would it have been checked?

 

I bet not. 

[EricJ]

10 hours ago, Shadrach said:

I think it is context. My primary use of torque seal is as a visual verification that a fastener has been properly tightened/torqued. My assumption was that most people use it this way. The auto industry does. 

It can't indicate whether torque was applied.    It can indicate if a process was skipped, or if anything has moved after it goes over a four-post shaker, which is probably what the auto manufacturers are using it for.

[Shadrach]

15 minutes ago, EricJ said:

It can't indicate whether torque was applied.    It can indicate if a process was skipped, or if anything has moved after it goes over a four-post shaker, which is probably what the auto manufacturers are using it for.

I totally agree. The reality is that nothing video graphic evidence can guarantee  torque was applied… The next best thing is to have a visual indicator that a process was followed and completed. Your premise seems to be that there is no benefit to having a process in place that generates a visual indicator that maintenance personnel completed a process which includes torquing the  fastener. I mean to disrespect when I say I think that is obtuse.  When conducting the final inspection if the inspector finds a fastener that is not marked, said inspector can reasonably conclude that the correct process was not followed and investigate. It is certainly possible that a fastener may be torqued and not painted. If that is discovered, the inspector can address it by ensuring the already torqued fastener is retorqued and painted. If indeed the fastener wasn’t torqued or painter, the outcome is the same…it gets torqued and painted. The notion that maintenance personnel would deviate from a methodical process and paint a fastener without ensuring it was properly torqued is of course possible but is a much lower probability in my opinion.
I’ve said my peice. Folks can take from it whatever they will. 
 

I don’t have your credentials nor your experience. I have however R&R’d more than one engine and completely removed and reinstalled the landing gear from several aircraft in addition to other maintenance processes that fall well outside of basic preventative maintenance.  I mark every fastener after it’s been torqued. It’s especially useful when fitting fuel and oil hoses, alternators, starters and other components where fasteners are hand tightened while components are adjusted before final torque is applied. Everyone that has been involved in the above mentioned endeavors has found this methodical process to be useful.  However, I’m always happy to read dissenting opinion.

Perhaps we should start a new thread called the Socratic Paradox of aviation maintenance. 
 

[N201MKTurbo]

I recently toured a medical device contract assembly facility in California. They recorded video the entire assembly process and the recording went into the DHF. If there is a CAPA, they can watch it being assembled.

[Parker_Woodruff]

16 hours ago, 1980Mooney said:

 

For those shops and A&P's carrying Mechanics Insurance:

• Are there any limitations or exclusions?
• Is it limited to employees of the shop or those employed by the A&P if they have a mobile service?
• Is it limited to certified aircraft mechanics working at the shop or for the A&P?
• Does it exclude any maintenance or "hands on" action taken by an owner? (i..e. the liability of the Owner's actions, even under supervision, remain with the Owner's Liability insurance policy?)

Let's face it - when you take your car to the dealership for repair, there is no "owner assisted" activity allowed.  They won't let you in the repair area.  I suspect their liability insurance policy restricts it to only employees.

I don't know if this falls in @Parker_Woodruff 's wheelhouse.  If Clarence were still here he could clarify ASAP.

I don't think I've ever seen such an exclusion.

[Hank]

1 hour ago, N201MKTurbo said:

I recently toured a medical device contract assembly facility in California. They recorded video the entire assembly process and the recording went into the DHF. If there is a CAPA, they can watch it being assembled.

Wow. I've been in medical device manufacturing for > 25 years, now with my fifth company doing so. Never seen or heard of such a thing, certainly never done it. Bazillion signatures in DHFs, though. 

[kortopates]

Pardon me, but I think this thread has become overly sidetracked by the maintenance induced failure not torquing the fuel line. yes that was very unfortunate which ultimately brought down the plane.

But this shouldn't have gone this far. The pilot had lots of warning with time to get back down safely in time. Climbing out at 3000' he noticed, about 4 min after takeoff, that his TIT was above redline. This is an emergency right here indicating the mixture is much too lean. He also remarked he saw the clear fluid on the windshield but apparently didn't equate is as the fuel that was causing his engine to run so lean.

He does the right thing by reducing power which could have saved the engine if it wasn't already detonating. But once TIT is below redline he tries to carry on, yet the fuel on the windshield isn't going away. In fact, in the report he indicates the fuel was increasing on the windshield. This apparently finally convinces him to divert 8 min after noticing the TIT over redline at 3000', based on flightaware data. I would hope pilots can connect the dots between the high TIT and clear liquid on the windshield and conclude it was fuel. Failing that, at least the need to get the aircraft down asap.

But the simple lesson for us all is to declare and take action to get the airplane down at a near by airport to get the issue sorted out. Lots of opportunities where missed to prevent this from turning into an accident. We never know how much time we have when we're experiencing an engine anomaly and this one shouldn't me mistaken for something minor that can be limped back to home base or the mechanic that did some recent work which also suggest the pilot realized it was fuel on his windshield. 

 

[N201MKTurbo]

1 hour ago, Hank said:

Wow. I've been in medical device manufacturing for > 25 years, now with my fifth company doing so. Never seen or heard of such a thing, certainly never done it. Bazillion signatures in DHFs, though. 

It was Paramit south of San Jose. They have quite an operation. I was impressed. Not cheap. I was amazed at the well known brands being assembled there.

 

Manufacturing

Device History Record with vPoke

Traditionally, a device history record is associated with significant costs in terms of human capital, space, process overhead, and even paper. Seeing an opportunity for innovation, Paramit created a patented, computer-directed assembly technology called vPoke. vPoke not only eliminates manufacturing defects from the assembly process but also automatically creates a device history record in real time as each sequence is completed.

If in the future a device fails in the field and you want to review the manufacturing process history for that device, we simply enter the product’s serial number to access and automatically generate the entire device history record, including picture images for each sequence. Going well beyond the industry standard for compliance documentation, vPoke lets us handle any inquiry for our clients.

[N201MKTurbo]

On 9/13/2023 at 1:02 PM, kortopates said:

Pardon me, but I think this thread has become overly sidetracked by the maintenance induced failure not torquing the fuel line. yes that was very unfortunate which ultimately brought down the plane.

But this shouldn't have gone this far. The pilot had lots of warning with time to get back down safely in time. Climbing out at 3000' he noticed, about 4 min after takeoff, that his TIT was above redline. This is an emergency right here indicating the mixture is much too lean. He also remarked he saw the clear fluid on the windshield but apparently didn't equate is as the fuel that was causing his engine to run so lean.

He does the right thing by reducing power which could have saved the engine if it wasn't already detonating. But once TIT is below redline he tries to carry on, yet the fuel on the windshield isn't going away. In fact, in the report he indicates the fuel was increasing on the windshield. This apparently finally convinces him to divert 8 min after noticing the TIT over redline at 3000', based on flightaware data. I would hope pilots can connect the dots between the high TIT and clear liquid on the windshield and conclude it was fuel. Failing that, at least the need to get the aircraft down asap.

But the simple lesson for us all is to declare and take action to get the airplane down at a near by airport to get the issue sorted out. Lots of opportunities where missed to prevent this from turning into an accident. We never know how much time we have when we're experiencing an engine anomaly and this one shouldn't me mistaken for something minor that can be limped back to home base or the mechanic that did some recent work which also suggest the pilot realized it was fuel on his windshield. 

 

When I was taking my ATP checkride, I told the DE about when I was training and we feathered an engine. Then we couldn't get it started. The Seneca was having a hard time maintaining altitude. It was, but I had to be perfect. one knot either way and it would start to descend. I told him where we were when this happened and that we flew it back to KGEU.

He ripped me a new one! I haven't been chewed out like that for a long time. He said I passed a perfectly good airport (KGYR) on the way to GEU He made me promise to never, ever pass a runway with a dead engine, or any other malfunction. It was good advice and I will keep my promise.

[Shadrach]

45 minutes ago, kortopates said:

I would hope pilots can connect the dots between the high TIT and clear liquid on the windshield and conclude it was fuel. Failing that, at least the need to get the aircraft down asap.

I would not count on that from your average weekend warrior. But, one would think that an owner that fancied himself competent enough to assist in a fuel system install might put two and two together. Not much surprises me anymore.

[kortopates]

6 hours ago, Shadrach said:

I would not count on that from your average weekend warrior. But, one would think that an owner that fancied himself competent enough to assist in a fuel system install might put two and two together. Not much surprises me anymore.

Sadly you're right of course.

I did listen to the pilots AOPA podcast. Although he first refers to the liquid as moisture, he quickly admits that his first thought was it had to be fuel since it couldn't really be anything else. 

[Shadrach]

35 minutes ago, kortopates said:

Sadly you're right of course.

I did listen to the pilots AOPA podcast. Although he first refers to the liquid as moisture, he quickly admits that his first thought was it had to be fuel since it couldn't really be anything else. 

I would think there might be olfactory clues in the cabin with that much fuel in the cowl. Him suspecting it was fuel I buy. Him tying the suspected fuel to the elevated TIT and deducing a leak at the servo is likely a bridge too far

[kortopates]

I would think there might be olfactory clues in the cabin with that much fuel in the cowl. Him suspecting it was fuel I buy. Him tying the suspected fuel to the elevated TIT and deducing a leak at the servo is likely a bridge too far

Suspecting it was fuel from the engine compartment should have been enough to take swift action to get back on the ground, If he could tie it to the elevated TIT it just reinforces how much little time he may need. Don't expect anyone could deduce the leak was at the servo. Nor would it be really helpful beyond recognizing there was a fuel leak to the engines fuel supply system.   

Update- in the podcast, pilot says he really suspected that it must be his fuel system leaking fuel, but that realization may have come after the event.

[Yetti]

On 9/12/2023 at 9:13 PM, 1980Mooney said:

Since this repair was "owner assisted" and many here have made an impassioned case for greater "hands on" owner involvement in Annuals and repairs, I am curious to know the position of the insurance companies providing A&P Mechanic's Liability Insurance. 

For those shops and A&P's carrying Mechanics Insurance:

• Are there any limitations or exclusions?
• Is it limited to employees of the shop or those employed by the A&P if they have a mobile service?
• Is it limited to certified aircraft mechanics working at the shop or for the A&P?
• Does it exclude any maintenance or "hands on" action taken by an owner? (i..e. the liability of the Owner's actions, even under supervision, remain with the Owner's Liability insurance policy?)

Let's face it - when you take your car to the dealership for repair, there is no "owner assisted" activity allowed.  They won't let you in the repair area.  I suspect their liability insurance policy restricts it to only employees.

I don't know if this falls in @Parker_Woodruff 's wheelhouse.  If Clarence were still here he could clarify ASAP.

I don't think you understand lots of things.   First off B nuts/AeroQuip/flare fittings/hydraulic fittings are not bolts.   You can hand tighten so that they won't leak, but with vibration will work loose.   I did this just the other day with my LP line on the generator.  I hand tightned the line a week ago and could barely get it off almost had to go get a wrench.   The seal is made via friction of the mating surfaces.   So yes it could pass a leak test and a hand tightness test then come loose with heat and vibration.       Second many shops employ non AP certified people to work on planes.   They may be working on the A/P or whatever.    My regular A/P does not do electronics because he is a great mechanic and airframe, but he knows his limits.   Now the story of the fire truck.   The Certified mechanic was trying to find why the pump panel and light bar and siren would not work.   I had previously found that no 12v was going to the siren.   After reading the schematics and seeing that the wiring was all CANBus the Real Mechanic was called in.  the Real Mechanic checked out the truck and called the factory for support cause he could not figure it out.   I showed up and read the schematic and saw that they pump panel and siren were getting 12v from one of the computers.  The schematic showed the computer to be mounted behind the air tanks on the frame rail.   I grabbed the slider and slid under the truck and wiggled the plugs on the computer.    Yea the truck is fixed.   I cut off all the tywraps and did a better job of tywrapping the wire harness.  Certified Mechanic - 0  ShadeTree Mechanic - 1

[1980Mooney]

2 hours ago, Yetti said:

I don't think you understand lots of things.   First off B nuts/AeroQuip/flare fittings/hydraulic fittings are not bolts.   You can hand tighten so that they won't leak, but with vibration will work loose.   I did this just the other day with my LP line on the generator.  I hand tightned the line a week ago and could barely get it off almost had to go get a wrench.   The seal is made via friction of the mating surfaces.   So yes it could pass a leak test and a hand tightness test then come loose with heat and vibration.       

No one ever said that a B-Nut was a bolt - not sure how you got that.  But you torque B-nuts/flare fittings just like bolts.   With a bolt (or nut on a stud) it is to create tension and to prevent the bolt (nut on stud) from backing off.  With a B-nut it is to create compression on the flare joint and to prevent the nut from backing off.  Maybe you are trying to make the point of tension vs. compression.

You can assemble many things with bolts or nuts on studs that are only hand tight.  They will look proper but also come loose (back off) with vibration.  Lug bolts/nuts on your car wheel are a good example. 

I hope that you don't make a habit of only tightening B-nuts/flare fittings merely hand tight as in your example.

Torque procedure at 5:30 in video

On jet engines they torque each B-nut three (3) times.

[Yetti]

45 minutes ago, 1980Mooney said:

No one ever said that a B-Nut was a bolt - not sure how you got that.  But you torque B-nuts/flare fittings just like bolts.   With a bolt (or nut on a stud) it is to create tension and to prevent the bolt (nut on stud) from backing off.  With a B-nut it is to create compression on the flare joint and to prevent the nut from backing off.  Maybe you are trying to make the point of tension vs. compression.

You can assemble many things with bolts or nuts on studs that are only hand tight.  They will look proper but also come loose (back off) with vibration.  Lug bolts/nuts on your car wheel are a good example. 

I hope that you don't make a habit of only tightening B-nuts/flare fittings merely hand tight as in your example.

Torque procedure at 5:30 in video

On jet engines they torque each B-nut three (3) times.

That's not even what I said.  Hand tight nuts and bolts will come loose when you check them after hand tightening.  Hand tight B nut and other similar fittings will pass the touch and wiggle test as though they have been properly tightened.    There should be no visual checking in Airplanes.   Touching and wiggling are the only way to do secondary and third check reassembly.  Even when I put the cowl back on I tap around it and see if a fastener comes loose.  Hopefully you don't just rely on visual checks.

Edited September 15, 2023 by Yetti

[A64Pilot]

22 hours ago, Yetti said:

  Touching and wiggling are the only way to do secondary and third check reassembly.  

I disagree, in the Army the policy was a TI (QC) had to see the wrench was correctly set and watch the fastener be torqued, then the Ti could stamp the write up as having been inspected.

So when I ran the assembly line in the Civilian world I expected the same, but it wasn’t even close, they held to the hand check of the lines and yes we had fuel leaks from that, I fought believe it or not to require the. to put a wrench on the fittings they didn’t witness being tightened to see if they could loosen them, unsuccessfully for a while as QC refused to get their hands dirty if you will.

QC had their own color of slippage mark that no one else was allowed to use, which if enforced is I think a good rule

Touching and wiggling does NOT work every time, you have to at least put a wrench on it and try to loosen it, if it’s only hand tight a wrench will easily loosen it.

Things were crazy, we would work overtime, without a single QC rep being in the plant, and the FAA had no rules against it. Of course I heard it’s always been that way and management didn’t want to pay QC who they say as being non productive workers anyway.

I ascended the management ladder if you will and was able to make those changes, but to a great extent things are as Lax as an owner wants and or is willing to pay for.

[Yetti]

6 hours ago, A64Pilot said:

I disagree, in the Army the policy was a TI (QC) had to see the wrench was correctly set and watch the fastener be torqued, then the Ti could stamp the write up as having been inspected.

So when I ran the assembly line in the Civilian world I expected the same, but it wasn’t even close, they held to the hand check of the lines and yes we had fuel leaks from that, I fought believe it or not to require the. to put a wrench on the fittings they didn’t witness being tightened to see if they could loosen them, unsuccessfully for a while as QC refused to get their hands dirty if you will.

QC had their own color of slippage mark that no one else was allowed to use, which if enforced is I think a good rule

Touching and wiggling does NOT work every time, you have to at least put a wrench on it and try to loosen it, if it’s only hand tight a wrench will easily loosen it.

Things were crazy, we would work overtime, without a single QC rep being in the plant, and the FAA had no rules against it. Of course I heard it’s always been that way and management didn’t want to pay QC who they say as being non productive workers anyway.

I ascended the management ladder if you will and was able to make those changes, but to a great extent things are as Lax as an owner wants and or is willing to pay for.

We are getting into work practice, it is a bit hard to require two people in the civilian world to tighten up a hose.  I don't think any of us could afford it.  It is better to have good work practice like never stopping mid assembly task. (sterile cockpit)   So do all the hoses starting one end and then doing the next end. Don't stop till all hoses have been properly torqued.  It's funny when I approach talk to an A/P I won't start speaking till they are done with the step they are on.