Rant: Exercising PIC, no not that PIC

LOL. That would be quite an act of intimacy in a Cherokee... I'd feel almost obligated to put a $20 bill in his belt loop for the dance.

We both got out :)
Wait you actually got out so he could check the tire? And you got back in? I'm pretty non- confrontational, but I'm pretty sure I would've pulled the plug right there.
 
Wait you actually got out so he could check the tire? And you got back in? I'm pretty non- confrontational, but I'm pretty sure I would've pulled the plug right there.
I don't know if I would've made it past the point where the guy was playing whack-a-mole with the fuel pump breaker.
 
Wait you actually got out so he could check the tire? And you got back in? I'm pretty non- confrontational, but I'm pretty sure I would've pulled the plug right there.
Yeah, we both got out. It was about 2 minutes later that I said he can drop me off.
To be clear: I'd made up my mind after the run-up I just was finding the right spot in the conversation to voice it. I don't even know what can cause an engine to run that rough. At least nothing I've ever experienced in any airplane I've flown.

I'll admit, I probably would have bailed earlier except for that fact he was a nice guy and I felt bad. I know that's not a great reason. But he had taken off work just to go fly. And here I was essentially saying "thanks, but your plane is a busted piece of **** that I don't feel safe in".
In the end common sense prevailed and I left fairly gracefully, but it took longer than it should have lol.
 
Yeah, we both got out. It was about 2 minutes later that I said he can drop me off.
To be clear: I'd made up my mind after the run-up I just was finding the right spot in the conversation to voice it. I don't even know what can cause an engine to run that rough. At least nothing I've ever experienced in any airplane I've flown.

I'll admit, I probably would have bailed earlier except for that fact he was a nice guy and I felt bad. I know that's not a great reason. But he had taken off work just to go fly. And here I was essentially saying "thanks, but your plane is a busted piece of **** that I don't feel safe in".
In the end common sense prevailed and I left fairly gracefully, but it took longer than it should have lol.
"Nice guy" sounds like a bad reason but it's kind of human nature to put the gloss on. Like others, if the repeating fuel pump breaker tripping didn't do it, that combined with the avgas smell, would have been the last straw. And if I was instructing them, all "nice guy" would get them is that I might not charge them for my time and the airworthiness ground lesson.
 
Yes, they are out there, but “typical” is an over exaggeration.
Is an "overexaggeration" worse than an "exaggeration?"

Those of us who are mechanics know that most pilots would be shocked at what we find in airplanes. Are you a mechanic?
 
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And the plane looked so sexy on the outside that there was some cognitive dissonance in my own head trying to reconcile what I was experiencing inside versus how nice it looks with fresh paint and a good interior and a brand new nav unit.
Yeah, I've worked on a few airplanes for their new owners. Nice paint and upholstery and radios sure do sell, but they are sometimes just lipstick on a pig. I used to find some sick stuff that should have killed the deal if they'd had a proper prebuy done.
 
All these old birds have some nits, but I think this would give me a serious pit in my stomach. Definitely would have made the same decision. You'd think with fancy avionics and a paint job, maybe a little money should be spent on things that won't cause you to become gliding manhole cover.

Now this makes me want to bug my A&P about my "it does that sometimes" that he says "they all do that". Lol.
 
even know what can cause an engine to run that rough. At least nothing I've ever experienced in any airplane I've flown.
My only experience with roughness came during training. As I advance throttle on run up I thought I heard something. Mag check was fine. Chalked it up to first flight with new headsets. Take the runway and advance throttle I hear it again. But it's worse. Instructor didn't hear it. Abort. And down the runway I'm playing with the throttle trying to diagnose. Instructor now hears it and asks what I think it could be. Out loud first thing I said was exhaust leak....but it would be a really bad exhaust leak. Is it down a cylinder like a plug wire came off? No, mag check was ok. Settled on exhaust leak. Instructor pulls the cowl, "nailed it!" One exhaust flange was only being held on by one nut, which eventually worked it's way off. The other stud was chowdered up and I pulled out the remnants of a failed attempt of a helicoil.

Took me back to the race car days. Tried to game the invert at national qualifier by pulling a plug wire in qualifying. Man did that thing run ROUGH. Felt like an idiot driving through pit lane. Was too good and too competitive and consistently fast to just go slower.
 
So new question is, knowing this guys keeps his planes in such a condition that you have to jump out because there are so many red flags. Would you even want him as a safety pilot in your own plane?
 
There are very few people who I allow in my Seneca. And there are very few pilots that I wil fly with, in their aircraft. There are a few, however.
 
Settled on exhaust leak. Instructor pulls the cowl, "nailed it!" One exhaust flange was only being held on by one nut, which eventually worked it's way off. The other stud was chowdered up and I pulled out the remnants of a failed attempt of a helicoil.
Such good inspections it was getting. The exhaust was one of the first things I looked at once the cowl was off and the oil draining. Cracks are common, some systems being worse than others, and I wanted to see if I would need to order new parts right away, or take off the cracked piece and send it off for repair.

The helicoil repair might have been just fine, but if the nuts back off and that riser starts jumping up and down, it stresses everything including the stud and helicoil. An unhelicoiled hole in good condition could get its threads stripped out.

One has to use a flashlight and a mirror to get a good look at the flange on the riser. Cracks often start along the weld between the pipe and flange, anywhere around the circumference. Some pipes have reinforcing overlay patches around the top, and thermal differences between the pipe and patch cause stress and cracking. Some aftermarket exhaust manufacturers don't smooth the edges of those flanges after they're cut, and the roughness represents stress risers and cracks start. AC43.13-1B has advice regarding dressing the cut edges of steel or aluminum parts to inhibit cracking.
 
Such good inspections it was getting. The exhaust was one of the first things I looked at once the cowl was off and the oil draining. Cracks are common, some systems being worse than others, and I wanted to see if I would need to order new parts right away, or take off the cracked piece and send it off for repair.

The helicoil repair might have been just fine, but if the nuts back off and that riser starts jumping up and down, it stresses everything including the stud and helicoil. An unhelicoiled hole in good condition could get its threads stripped out.

One has to use a flashlight and a mirror to get a good look at the flange on the riser. Cracks often start along the weld between the pipe and flange, anywhere around the circumference. Some pipes have reinforcing overlay patches around the top, and thermal differences between the pipe and patch cause stress and cracking. Some aftermarket exhaust manufacturers don't smooth the edges of those flanges after they're cut, and the roughness represents stress risers and cracks start. AC43.13-1B has advice regarding dressing the cut edges of steel or aluminum parts to inhibit cracking.
Sorry, bit of a thread detour but why is it that cracks in exhaust are so common? When I bought mine that was one of the first repairs we had to do.
But it's never made sense to me. It doesn't seem like a part that takes a lot of physical abuse that would result in physical cracks (discounting the temperature fluctuations it experiences).
 
But it's never made sense to me. It doesn't seem like a part that takes a lot of physical abuse that would result in physical cracks (discounting the temperature fluctuations it experiences).
Don't discount those temperature fluctuations, and try to understand the temperature gradients between parts. That exhaust system can glow red-hot at full climb power, so expansion and contraction are a big issue. The riser flange is bolted flat to the head, and the head conducts heat out of it, so that flange is never red-hot or anywhere near it, but the pipe just below will be really hot. The pipe is expanding more than the flange, and that stresses the welded area. As the red-hot pipe is being restrained by the weld to the flange, some compression of the hot metal takes place. When the engine is shut down, that pipe cools, and now it's shrinking to a smaller size than it was before, due to the compressed metal, pulling hard at the weld.

And as I mention, the triangular overlay patches to reinforce that area introduce problems of their own. They are welded around their periphery, but are just snug against the pipe everywhere else, so the pipe gets real hot from the flaming exhaust gases, while the patch gets cooling air off the cylinders. That stresses the patch's weld, pulling at it and often starting cracks. On the 172s I often had less trouble with the unreinforced risers.

EGT can hit 1700°F, right? Steel and its alloys start to glow around 1100°F. So we have intense heat, flame, way hotter than the exhaust system in your car ever sees, and the car's system is made of much thicker stuff. How often does the car's engine run at full power?

Add in vibration, lots of it. And the exhaust itself is made up of plenty of corrosive compounds that eat the system from the inside. Eroded tube ends inside the riser flanges, slip joints and muffler connections are common.

One has to take exhaust system integrity seriously. Beside the risks of carbon monoxide, escaping hot exhaust gases can set stuff afire inside that cowling. Remember that around 50% of the gasoline's thermal energy goes out that exhaust. An awful lot of heat.
 
It does happen in cars, too. I owned a new 1970 Barracuda that developed a cracked exhaust manifold.
I once had a 1978 Dodge pickup (worst vehicle I ever owned, btw) that had the 225 Slant Six in it. The exhaust manifold cracked in a couple of places. I think a previous owner had "snugged-up" the nuts of the manifold studs, exactly the wrong thing to do there. The torque specs are fairly low, with the idea that the manifold can shift on/around those studs as it gets hot and then cools off. Those long one-piece manifolds are bad for that. They expand more than the head does, and need to slide a bit.
 
Such good inspections it was getting. The exhaust was one of the first things I looked at once the cowl was off and the oil draining. Cracks are common, some systems being worse than others, and I wanted to see if I would need to order new parts right away, or take off the cracked piece and send it off for repair.
It was prior to first annual of my ownership. Found a handful of things that were concerning. When i bought he said he had a minor oil leak they couldn't track down. Was the housing for the oil screen. Dye and black light found right away.
 
Or reasonably similar financial position it sounds like.

That’s half the equation. In my partnership, we could all afford outright ownership but that hasn’t prevented heated debate around fixing airworthiness items.
 
That’s half the equation. In my partnership, we could all afford outright ownership but that hasn’t prevented heated debate around fixing airworthiness items.
Seems like it should be a short conversation if it's an airworthiness item?
 
The only ship that won't sail is a partnership...

I'd actually like to put together a partnership on a decathalon. I think (naively?) a vfr airplane would have less arguments than trying to decide how much money to throw at avionics.
 
Seems like it should be a short conversation if it's an airworthiness item?

Spoken like someone who’s never had a partner. The most popular question is “Cam we defer that?”

Mind you, it’s a paid for plane with a fresh O-320, GTN650, and dual G-5s and $40K cash on hand.

We have some filiform corrosion around one of the antennas; the conversation isn’t about getting it fixed at our next 100hr, it’s about whether the cost to fix it is worth just accepting the risk since “it’s not that bad.
 
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Spoken like someone who’s never had a partner. The most popular question is “Cam we defer that?”

Mind you, it’s a paid for plane with a fresh O-320, GTN650, and dual G-5s and $40K cash on hand.

We have some filiform corrosion around one of the antennas; the conversation isn’t about getting it fixed at our next 100yr, it’s about whether the cost to fix it is worth just accepting the risk since “it’s not that bad.
Yeah, that's fair. I haven't had a partner. Largely for this exact reason. My safety and comfort isn't open to democratic vote. I'm too dictatorial for it lol.

But yeah.. I guess not all airworthiness items are created equal. I can see how some would be kicked to the curb. But unlike wine these maintenance issues don't usually improve with age.
 
Steel and its alloys start to glow around 1100°F.

Sure. I think everything else does too. That's why these Temperature guns work, everything glows the same way.

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