DXB

Shallow and/or antiquated views on engine maintenance seem pretty common among A&Ps. It seems like many never go much beyond faa and manufacturer regulatory guidance in their understanding of what contributes to safe and reliable engine operation. I wonder how much is taught regarding borescope usage and engine monitor interpretation for instance in modern curricula. Mooneys as you know have some systems with idiosyncratic design relative to aircraft of the same class - control surface linkages, trim, gear. I'm not sure how much A&P curricula help here. BTW what you're doing is great - owners with A&P background are highly valuable to the Mooney community. I hope you stick around in the coming years....

Get the ones @jetdriven mentioned. No need to dig though part numbers - many have been resized from the old factory spec anyway so the original part may not fit your setup. Just send Aero Hose Shop your old ones to duplicate with 124JJ - low profile, integral fire sleeve, indefinitely long service life - far better than rubber hoses for not much more money. I just used them to replace all oil and fuel hoses firewall forward at time of overhaul. It was ~$1400 total. They were great to work with and had a 1 week turnaround. Contact Ben McNamara. (I have no relationship to this vendor - I was just pleased with their service).

This respost notification triggered terrible memories -thanks for nothing . Of note the pitch servo did evenually go back to working normally without my having to pull it. But I haven't fogged my plane since that date, and I probably should consider doing it again. I wonder what the safest most modern approach is.

My JPI 900 is quite solid and reliable now. The issues were all install related. JPI's technical support is spotty in quality, so it took a long time to troubleshoot properly - by contrast to EI for instance. I suspect your situation is the same.

Apparently the CVR was at the base of the main impact crater - blows my mind that this thing is predicted to be readable

Are you referring to "specks" in the form of abundant ferrous metal sticking to a magnet when you run it over the filter (which is concerning), or just the oil analysis (which is much less concerning - so much so I'd suggest quit with the oil analysis, which is generally not actionable information). If visible "specks" are nonferrous, analyzing their composition via Avlab can be informative, as mentioned already.

We don't know the identities of the pilots and their experience/training records yet, but this question of competence will at least be partly answered. The company is based out of both Mexico City and Miami and operates in the US under part 135 rules. https://www.jet-rescue.com/

Perhaps some minor or major distraction in the cockpit or cabin? The distraction could be human in nature or, perhaps more likely here, aircraft systems related and lead to commanded or automatic disconnection of the autopilot after they first tried to engage it. It seems like they never made the turn to assigned heading of 290, which should have been in the heading bug and followed by autopilot. Spatial disorientation may have become the key factor once the autopilot was off, assuming it was ever on. It also seems like these possibilities will be nearly impossible to sort with a pulverized/incinerated aircraft and no CVR/FDR; however, this broad category of issues seems more likely than a catastrophic, unrecoverable aircraft systems failure, particulary given poor weather plus nighttime.

Taking off into low IMC is serious business in a Mooney or any other bird. This departure was into 6SM 400 OVC BR on Friday night from my home drome and tragically ended 40 seconds later in a crash into a densely populated area resulting in at least 7 deaths (including 1 person on the ground), several serious injuries on the ground, and major property damage. I find Juan Brown's interpretation of spatial disorientation LOC here compelling (albeit admittedly speculative). Sadly we might never know much more given lack of CVR/FDR and the pulverized state of the wreckage after a steep nose down impact and massive fireball. I'm curious what the seasoned folk here think about this disaster and how they personally handle such departures. I'm far from a pro, but I'm forever grateful to my IR instructor for having taken me through real departures like this, and I continue to hear his voice any time I climb into IMC...

Does anyone else with bladders worry there's spar corrosion hidden under their old sealant, and now permanently hidden upon bladder installation?

Outstanding, detailed guidance, particularly for any owner taking a plane to a prebuy. Speaking about this stuff in advance to the A&P involved seems critical to prevent a lot of potential pain.

Interesting question - I'm not sure. In my case, I chose to turn the prebuy inspection into an annual (which is when the cylinder was pulled and the cam corrosion was discovered). In that context he certainly did have ability to ground the plane. As an aside, he mentioned several vintage Mooneys that had come to his shop for prebuy over the years and never left due to discovery of serious spar cap or steel cage corrosion. He showed me an old C with corrosion of the cage that was languishing in the back of his hangar after the prospective buyer getting the prebuy walked and the owner was unwilling to pay the substantial repair cost. I wonder what the dynamic there was. Also BTW despite my one substantial disagreement with him, my impression was that he and his crew run an excellent operation overall, and I would go back to him in a second if I were in that part of the country.

It's important you brought it up with them and also that you got the expletives out of your system before doing so. It's rather tricky when a mechanic or shop known for reliable work seems to overcharge. The number of qualified A&Ps available to help with our planes continues to shrink, and I tend to give the benefit of the doubt and prioritize maintaining any working relationship...unless they've done something willfully and egregiously fraudulent. Fortunately that has been confined to a single experience for me - charging >1amu for tightening an alternator belt - It was fortunate in retrospect that no punches were thrown by the shop owner and there is no lien on my plane after I refused to pay that bill. I definitely can't set foot in that shop again though...

Can't negotiate it as such very easily if you don't have evidence of corrosion on the bottom end. You can walk away if there's metal in the filter/screen, but you can't collect evidence of an issue unless you can pull a jug as part of prebuy. Most sellers won't let you pull a jug. These are relevant considerations during a prebuy.

I wouldn't split the case to IRAN. Negotiating it as a high time or run out engine is reasonable, but the jug got pulled after the plane was bought and the discrepancies were being worked through. The filter/screen were clean at prebuy, Most sellers won't let you pull a jug to look at the bottom end on a prebuy (and neither would I).

This type of borescope inspection of any cam lobes/lifters that aren't directly visible should be standard whenever a single jug needs to be pulled for any reason. I suspect it rarely gets done though the necessary tools are widely available and relatively inexpensive.

CAM LOBE CORROSION? A DULL TALE OF 1200 HRS SAFE LYCOMING OPERATION Surface corrosion noted on a cam lobe after pulling a jug isn’t great, but in isolation it is a terrible reason to split a Lycoming case – it may need overhaul soon, or maybe not... My illustrative anecdote: >10 years ago, a newb pilot/owner buys an M20C with a 600hr SMOH O-360 that had spent some time sitting and needs a little cylinder work at the outset. After pulling a couple jugs, the well-known Mooney A&P/IA who did the prebuy finds surface corrosion on multiple internal components and even some pitting on cam lobes but normal lobe height and lifter faces. The A&P sends pics of the extensive pitting and says newb owner you must overhaul. The collective “wisdom” of the internet also says that the newb pilot/owner/doctor must overhaul and asserts that he is just another vertical-tailed doctor killer-buying sucka. His demise in a smoking crater seems likely to all because he is arrogant enough not to accept A&P or internet guidance without asking questions. The sucka pilot then takes deep dive into authoritative literature by Mike Busch and others, learning that (1) there is zero danger in running it until cam/lifter truly spalls and (2) it’s easy to monitor the situation through the filter so that once it happens, further damage to the engine can be prevented. Armed with real knowledge, the arrogant newb pilot/owner pushes back hard against the A&P/IA, getting him to sign it off under some duress. Though this newb’s demise seems imminent to all, he flies regularly, uses Camguard, and keeps engine dry in winter by heating it uniformly and continuously. He also cuts and scrutinizes his filter nervously at every oil change, finding nothing for many hundreds of hours. He gets a good engine monitor, learns how to use a borescope, and learns spark plug maintenance, allowing him to monitor the top end as well. He does oil changes and oil analysis religiously but ultimately quits oil analysis after learning enough about it to conclude that it’s utterly useless for real world maintenance decisions on this engine. Finally, after flying for another 1200 hours over 10 years and accumulating ample instrument time, he notices a subtle but consistent decrement in TAS on recent flights. At the next oil change, he finds ample ferrous shavings in the filter (pic). He had become lazy recently and was only cutting every other filter, and so he pulls the previous filter off the shelf and also finds similar metal, realizing that he flew about 80-90 hours with cam lobe(s) and lifter face(s) coming apart. He flys it one last time to a major engine shop 3hrs away for overhaul, marveling at the aircraft’s fast and smooth performance during this serene flight and wondering if he is making the right decision. At overhaul, the suspected cam/lifter spalling is confirmed, and metal shavings are flushed from the oil cooler and governor. The prop is IRAN’d/resealed, and the hub is found to be in fine condition, as is the crankshaft. He’s finally back in the air and still (mostly) enjoying the continuous learning involved in the Mooney ownership journey….

Welcome! It's a terrific plane that fits your mission. There's TONS written here about prebuys here on the Vintage birds. Google Mooneyspace prebuy (or similar, the search function for the website sucks). Make sure key components of the airframe are corrosion free first (wing spar, steel cage for cabin). If it checks out, then move on to evaluating the rest. If you can find one with good avionics, it will save you a ton of money and time upgrading, but focus on the basics first when assessing a plane.

Ah - thanks for that info. Looks like it would save me about $130 / year to switch ($109 for the GP base subscription vs. $240 for Foreflight Pro Plus). It may not be worth the hassle yet.

I've been using Foreflight since I was a PPL student back in 2013, despite their rising subscription prices and transformation from a scrappy innovative startup to now being part of Boeing, a relationship which gives me the icks. I just found out I've also been paying for Garmin Pilot as part of my Garmin database purchases for my GTN650. I've no clue how long this has been the case. Did y'all know this already? Why didn't you tell me? The pricey Garmin database subscriptions are of course one of the great free data repackaging scams of our time. However, the access to Garmin Pilot at no added cost makes me consider switching to save on the cost of Foreflight. Has anyone done this? How much of a risk / hassle is the transition? I'd hate to create a smoking crater because I only know how to pull up an approach plate on Foreflight at the moment. Also other hidden costs if I do make the switch?

They are terrific radios.

Mine will My C is somewhat modded and has a Powerflow. At 4000-7000ft, 10gph, it is a solid 150kt TAS machine at around 24 squared. Under perfect conditions in the winter, it can push 155kt TAS at those altitudes and settings. Your IAS is 150kt - assuming an OAT of 0C, that's about 162kt TAS - which would be insanely fast for a C.

Seems like pretty typical behavior for the rate-based STEC-30. I've flown behind one for almost 10 years. It is precise enough to follow a course enroute decently via your GPS. Unless the wind is calm, it does a terrible job flying approaches (e.g. either RNAV or ILS) because of the greater precision needed. I think the fact that it did a decent job with the RNAV was just luck.

Glad to hear your friend is ok. Hopefully the fence and blueberries have enough give to them so as not to kill anyone. In this case there was a concrete wall created to mount the antennas on top rather than the collapsible supports standardly used for these installations. South Korea ain't some 3rd world country so they probably could have afforded to do it right. It may have been just laziness/expediency.

The decision to mount the localizer antennas on a tall barrier is only one of many utterly baffling elements to this tragedy.