Leaderboard

It’s been some time but wanted to share with you the painting I did for last years silent auction at the summit. I Don’t know if the winner is someone that visits Mooneyspace but wanted to thank them for their contribution to the Gilliland (spelling corrected) foundation. Was very nice working with them and I was very happy with the results of my work as were the recipients. They run Cadillac aviation in Michigan. John

For your entertainment and viewing pleasure, I will be presenting Anthony @carusoam on display at the Dean of Mooneyspace Lunch Fly In at 47N Central Jersey airport at noon on Saturday 4/20/24. Free autographs on a first come first serve basis. You might even have the opportunity to buy him lunch. $5.35 100LL self serve. Park on the main ramp and a very short walk out of the airport to the restaurant on the corner of the road leading into the airport. Don't let the name "Pizza 'n Pasta" fool you. This place has Stromboli's, Calzone's, and other Italian delights such as Anthony Caruso. Need I say more?

I try not to ascribe duplicity to any situation where ignorance or dare I say, stupidity will suffice...unless I have firsthand knowledge that suggests otherwise. I did not know this pilot, but I also find it hard to believe that he did not understand that the undisclosed medical conditions for which he received treatment were disqualifying without an SI. However, I never underestimate people. I met Mooney owner just last week with a beautiful 201 that he said "cruises at 180-190kts, depending on the wind". He did not pick up on my confused look at all. The conversation did not last much longer but what remained of it convinced me that I often over estimate intellect.

Is there any evidence the lack of medical was the cause of the crash? The NTSB didn't think so. Is your contention he should be denied insurance despite the fact that the rule he broke was completely unrelated to the cause of the crash? If so, why stop there? What if he was fleeing from robbing a store but was otherwise legal? Should he be denied coverage because of that? After all, the crime is unrelated to the crash but he did just break the law, not just an FAA regulation. Or, is it just 'anything' you decide is related to aviation? So, if you knowingly fly one day out of 90 currency and crash should you be denied coverage? How about if you knowingly fly 1 pound over gross and crash due to running out of gas? Heck, there is a reg about carrying sufficient fuel so why isn't that a deliberate violation... I mean, you must have been cognizant fuel was low but deliberately and knowingly continued on anyway. Deny that coverage, right? Flying to your annual a few days after your old annual expired because of a weather delay? This guy, even per the NTSB, didn't crash because of lack of a valid medical but from spatial disorientation. Why do you feel he should be denied coverage for something unrelated to the crash? A better argument would be that he was out of instrument currency. So, we are back to who is the arbiter of how far out is too far out before coverage is denied? I'm comfortable with the insurance companies making that call. I guess I'm just tired of all the holier than thou Monday morning QBs looking for any reason to deny insurance coverage so their precious premiums don't go up. The worst are the ones that want to deny coverage for gear ups! But the moral high ground argument (oh, he broke the 'rule' so DENY, DENY, DENY!! I'm so righteous.) are tiresome, as well. Ever knowingly drive over the speed limit? Think your auto insurance should be denied if you crash while speeding? How about someone injured by your illegal actions, be they in an auto or an airplane? Should they be denied compensation from your insurance because you broke a rule or law? How about your example: you let someone drive that isn't licensed and they injure someone in a crash and you don't have assets to cover since the insurance denies coverage? Does that seem just? Change it up a bit: your unlicensed hypothetical driver is in an accident that is NOT his fault; he's sitting at a signal and is rear ended at a stoplight by an uninsured driver. You okay with your insurance denying coverage? How about if someone else in your car is injured? Still okay with coverage denied? Be careful on that high horse; the fall may hurt more than you might think.

+1 that Varsol is essentially a brand name for a particular (supposedly purer) type of mineral spirits. The brand is currently owned by Exxon Mobil. Stoddard Solvent is similarly just a particular type of mineral spirits. It's like "Kleenex" or other brands that have become product names; unless there's some reason to believe otherwise, they mean "mineral spirits". Stoddard Solvent was branded as a dry cleaning agent. There's nothing special about it for aviation use, other than it is less flammable than gasoline so safer as a general solvent. Another thing that is often used for ring flushes is Marvel Mystery Oil (MMO) which is usually available at places like Wal-Mart or auto parts stores. People often use MMO straight without mixing it with anything. FWIW, MMO is mostly mineral spirits but also has some other interesting stuff in it. If you want you can cut it with your favorite motor oil, but it's probably fine to use straight. Whatever you do, after the ring flushes are finished, don't run the engine until the oil is changed (probaby goes without saying, but is mentioned for completeness).

So the pilot of the Cirrus that spun in at Love Field in 2016 was at 25 months since her last flight review so just one month out of currency. One could make the argument that her unfortunate lack of airmanship might have been corrected prior to the accident had she received a proper FR in the weeks leading up to the accident flight. It's no stretch to attribute that accident to task saturation and poor airmanship, the very reason we get a flight review is to identify and rectify deficiencies in our performance. Legally out of currency and a fatal accident attributed to poor airmanship. Should her insurance have denied to cover that loss? The same case could be made for the Mooney accident. Much easier to make the case that his lack of instrument currency was causal when compared to the medical issues. I'm sympathetic to your view point, but I think that the professionals in the industry have repeatedly encountered this situation and found it preferable to err on the side of paying claims in spite of bad boy/bad girl acts. In the case of this Mooney accident, you appear to be implying that there was intentional and deliberate fraud with regard to this pilot's policy renewal. I don't think we have enough information to be sure of that but it's certainly a strong possibility. In such a case, I think it's prudent to pay the liability claims but the pilot and their heirs do not collect.

Update, the belly pan came off and the chain was sitting there with the connector link missing its retainer lock thingie. With the help of this group I was able to find a replacement connector link on Amazon. I showed it to my mechanic and he said that will work perfectly. I got four of them for five dollars. It has to be the cheapest aircraft part I’ve ever bought. I have three now available for sale at $250 each if anybody needs one.

What the other guys are saying nicely is that you’re not leaking a qt/4 hours. If you were, you’d be shocked at what the bottom of the airplane looked like. You’re likely leaking a tablespoon per 4 hours, but hot oil spreads very easily and makes a big mess. I’m not saying that your oil level doesn’t go down by a qt/4 hours. Actually that’s not terrible, but it’s unlikely caused by a leak. Oil can also go out the breather or through the exhaust valves. Blow by of the rings is pretty common and will significantly increase your oil loss. These things do use some oil. Now there’s absolutely nothing wrong with finding/fixing your leak (we all have small ones), but don’t expect it to change your oil use. Most of these engines use a qt/4-12 hours depending on cylinder type and age.

Don't put the bait in the hangar! Your hangar should be a "food desert" they don't want any part of crossing into. Bait is food. Place the bait outside in run in cubes and not close to the hangar. Make sure no one, and I mean no one has any food in or near the hangar building. No food, no mice.

God help me if I ever track my expenses. The airplane would be up for sale the next day.

Call Herber Aircraft. They are a Lord distributor and consistently have the best pricing on Lord products. Their parts people are very good and will be able to help. A bonus for you is that they are in El Segundo.

My fear is always about the power lines that you can't see until you're right on top of the road.

I would never want to second-guess a successful emergency landing with no injuries to person or plane, but I usually think of a highway as a last-resort landing option. I wonder what factors led to the highway decision.

Mooney N58089 $175,000 OBO 1985 M20K 305 Rocket Serial 25-0872 Based at: KHEG (JAX area) and 6D6 (Hastings, MI) TSMOH: 602 TTAF: 2894 TTE: 2000 Prop: 602 Annual due: 11-2024 IFR Cert Due: 04-2025 Empty Wt: 2230.4 Empty Wt CG: 42.87 Useful Load: 969.6 Avionics: Garmin GI-275 Engine Monitor, Garmin GNX-375 GPS w/Transponder, PMA-8000 Audio Panel, Garmin GTR 200B VHF Com, Garmin G5 HSI, Garmin GNC 255 Nav/Com, King KAP 150 Autopilot w/297 Altitude Preselect. Full IFR panel makeover 9-2022, USB port included. Detailed Description: 1985 Mooney 305 Rocket. 2894 TT, Turbo Continental 520, Garmin GI-275 Engine Monitor replaces all engine instruments, Garmin GNX-375 GPS with Transponder, Monroy Long Range Tanks, Speed Brakes, Four Place Oxygen. Misc: All logbooks digitized, extras include instruments removed from panel upgrade in 2002, LED landing light installed 2021, nose gear landing pucks replaced 04-2024, Mike Busch books, customized aircraft cover & accessories, 2 lightspeed headsets, and various other aircraft consumables. Currently subscribed to the Savvy Aviation maintenance concierge program which is transferrable. Additionally, I have a Garmin database subscription that expires 10-2024, which may be transferrable. Extra SD card included for database updates (handy!) Note: I bought the plane 3 years ago and installed the new panel, as well as cleaned up some deferred maintenance items. The plane is a beautiful, fast cross-country IFR platform that burns approx. 18 gal/hr at cruise of over 180kts. It has a 100+ gallon fuel capacity, and 4+ hours range. Unfortunately, due to health issues in the family, and a change of mission, I need to sell it. Google drive link for all logbooks, pictures, etc. More pictures to come! https://drive.google.com/drive/folders/1oTd_xgbmIGT7MtCUBK49v5czTQ8zBwwZ?usp=drive_link

Take it off and clean it real good by scrubbing it with a tooth brush and comet cleanser until it rinses off clean, inside and out. Then get some 1oz fiberglass cloth and cut it into patches a little bigger than the hole. Apply a thin coat of black RTV around the hole, on the outside and stick on a piece of fiberglass. Then apply a little RTV over the patch and work it into the cloth till it is saturated. Massage it until it fits the shape of the boot folds and doesn’t protrude into the boot. Now apply another piece of fiberglass and cover with RTV. Let it cure overnight. If there are any fringes of fiberglass, trim them with a surgical scissors. Then add another thin layer of RTV to make it look good. All RTV work should be done with rubber gloves on. The RTV layers should be as thin as possible while saturating the fiberglass. The RTV will only bond to the boot if the boot is clean and dry.

There is a little chain that connects to the trim wheel. The chain can pop off if it isn’t properly lubricated, and when it pops off the wheel will spin freely. Definitely talk to an A&P because you’ll want to rule out a need to lubricate the trim jackscrew. But this might be a 5-minute fix.

"The difference between intelligence and stupidity is that intelligence has its limits" Supposedly said by Albert Einstein

Would be interesting to know how many of the pilots on this board have had an "oh $h!#" moment discovering an overdue flight review. Harder to do in this day of electronic calendars, but still possible.

We all have our preferred set of actions and situations we want covered and those that we don't want covered. Why don't we exclude from health insurance coverage anybody who doesn't actually follow the doctor's advice on dieting, exercise, and smoking? I remember someone on mooneyspace wanted to reject coverage for any flight with a special flight permit. And I think someone else or maybe the same person wanted to reject fuel exhaustion claims. There isn't a large enough pool of people to offer specific policies for each set of things people want covered or not. If you have not heard this line that I think started with George Carlin: Have you ever noticed that anybody driving slower than you is an idiot, and anyone going faster than you is a maniac?

An Insurance policy is fundamentally a financial contract between the indemnifier and the indemnified. The limits and limitations of the policy are codified within the contract. An accident/incident either falls within the bounds of coverage or it does not. It’s not a moral decision. It’s not about accountability for one’s actions. It’s simply a contract. Accountability for criminal behavior is for the criminal courts. This is not a new concept nor is it a byproduct of neomarxism.

To reiterate @Shadrach, and others, what do you buy insurance for? To cover YOUR MISTAKES! Do you really want to pay for a policy that is going to deny YOU coverage because YOU broke a rule? Be VERY careful for what you wish for when saying, "You would think" insurers should deny coverage for legally errant pilots. Ask yourself how many accident reports you have read where the pilot was innocent of any and all transgressions.

You are still in the normal range, but something is somewhat different. If it were mine, I'd just watch it, and if it doesn't get worse, I'd see what happened after the next filter/oil change. If you are worried about it, you could just change the filter and see if that makes a difference since that is the only part that was changed.

clean real well with mineral spirits, let dry, spray suspect area with white developer from dye penetrant system, run engine on ground for 10 min on ground at 1200 rpm, check if you see any traces of oil in the developer, if not go fly airplane for 20 min so all engine parts are at ops temperature, land airplane, pop cowl and look for oil traces, this will give you an idea where the leak is, if there are still doubts, clean everything again, spray smaller area with developer and run the engine again, no black magic, just persistence does the trick

Funny enough, I just come across a British friend who told me that Guy Ritchie bought his airfield in UK, saving a historical aviation heritage (that would have gone to property developers), now he is running it with such enthusiasm, well done Ritchie, GA is a small world as they say https://flyer.co.uk/guy-ritchie-confirms-flying-to-continue-at-compton-abbas/

Final- https://data.ntsb.gov/carol-repgen/api/ ... 105237/pdf Docket- https://data.ntsb.gov/Docket?ProjectID=105237

It is impossible to seal everything. I keep a couple of bait stations in the hangar and a couple of ultrasonic devices plugged in and sometimes I've tossed a peppermint oil repellent bag in the baggage compartment. So far, I haven't had an issue.

Rounding error. Go fly the plane.

My IA claims he will get a big old military piece from the 60s from a friend in Jersey before he kicks the bucket, then we will overhaul and test our own mags, let's see.

I would take your focus off of whether a shop has to be a repair station to do the work. You want a specialist who does mags successfully every day to do the mags on your airplane. You do not want someone learning on your mags. There are a few good shops across the country that do mags. Having one close to you is not nearly as important as finding an excellent shop - that's what UPS and FedEX are for. But now drilling down to your specific mag, if one of the best shops in the country, Aero Accessories, won't do them I would pay close attention. That means that even with their very high standards they have a high failure rate. Internal parts can be replaced with new, but is it the housing that wears and makes a reliable overhaul improbable? Why the high failure rate? You must have a good A & P, since he realizes that a great shop has turned down the work - why would he want to put his reputation and your life on the line? Are you noticing a pattern here? People who make their living doing things like this are turning down your money - very unusual in aviation that anyone turns down your money. There must be a good reason. Talking another A & P into doing it may not be a good choice. Slick mags when they came out were regarded as "disposable" mags, even though some models were better than others. I would explore better options: Does Bendix make mags for your engine? Does Slick make new mags for your engine that May have been updated and improved (even though new Slicks haven't had a perfect reputation the past few years)?

If you are stranded away from home and cannot find a link, I don't see why a temporary repair could not be made using some .020 safety wire in place of the clip.

The IPC just says, "Chain, master link, #25 pitch." I don't think there's anything special about it. A bike shop or hardware store probably has one.

I recently sold some pedal extensions and some other loser tried to get payment directed to him. And a month ago I sold some brake masters and the buyer got scammed out of a deposit. There are bad guys amongst us, sometimes its easy to spot, sometimes not. Don

Let me know when @carusoam does his Texas tour.

I hate being “that guy”, but you’ve got one glaring error that needs to be addressed so no one gets hurt. It’s wintergreen, not peppermint.

Hi Don, I find the ground situation completely different now that I have a wood wing Mooney. David

Vacuum pumps fail a lot more than AIs AI failure is rare Want a good power system for the AI that can't fail in Mooneys? Get it powered by a venturi If you have flying speed you have a good AI Don't talk about ice- you shouldn't be in that kind of weather in a Mooney anyway Which one of 2 AIs has failed ? Try it sometime"-) for real IMC (sim or flight I don't care) In the 121 world 3 AIs is mandated We used the 'best two out of three" syndrome. Had a chief pilot once on a CE 500 who couldn't handle the check ride when they failed his AI. Couldn't disregard his bad instrument and go small third or transfer controls to my side. I'm left wondering what the old Pan Am pilots on the Clipper Ships did around the world when they didn't even have gyro AIs back then? "Here kid, you fly this thing needle ball airspeed" They didn't piss a moan about "partial" panel because that was ALL the panel they had. No such thing partial panel then. AND in some cases they had one needle in the center of the entire panel to look at. Had several what we called "autopilot cripples" in the 121 world. Without it they couldn't get it down inside the fences at the airports- LITERALLY! Always hand flew every third approach by hand to keep sharp. Many down to CAT III mins just in case In the AB 319 I would fly an ILS by hand as I don't think their stability program is all that good. In smooth air it always seemed to wallow around coming down the slot. Autopilot dependence and "Children of the Magenta Line" go hand in hand. (If you don't know of the training film "Children of the Magenta Line" you owe it to yourself to go to utube and watch it. )

If it’s the chain, the indicator will move with the electric trim. If it doesn’t, the trim torque tube is disconnected somewhere.

Y’all are not true CB’s. I use the packing paper in Spruce boxes to making an oil drain channel. Since the paper isn’t rigid, it is easy to push up under the oil filter. I also usually wait a day to remove the filter. Lee

The Story: I bought an Ovation last October that needed some attention. My son and I are going to travel in it and he is building time for a flying career. It had a new and very nice glass panel in it but everything else was well used. The airplane flew about 35 hours in the last 5 years. The paint was very oxidized, carpet old and dirty worn through and the seats looked like a frat house couch. Both wings had fuel leaks. It had been well maintained but it was tired when i bought it. I used the Winter months from then until now to refurbish the airplane. I tackled a bit more than i wanted to but my thinking was to fix everything now and fly it versus fly-it-and-fix-it etc….. So, this is what we did: Firewall forward is all new. Every line, hose and connector. Factory new IO-550. New engine isolators. Stripped and painted the engine baffles. Prop Governor Overhaul Prop Overhaul to include new internals. Compete external light conversion to Whelen (WATT) LED’s. New wingtip and taxi/ landing light lenses. New tires and tubes. New batteries (2) New O2 bottle and fill. Polished the spinner and took the dents out. 18 hours with a buffer and ceramic wax to bring the paint back to life. Complete fuel tank seal scheduled for this year. New Interior. (I started with the just carpet but I had to take the seat out to take out the carpet………and one thing led to another and i just took everything out). I also removed most of the old adhesive, cleaned every inch of the inside and added insulation and sound proofing to the interior. FIRST FLIGHT: Accomplished the first flight and first two hours of engine break-in yesterday. The new engine and prop are powerful and smooth. Everything else mostly worked as advertised. After the first hour I landed. We took the cowlings off to inspect. No leaks. We adjusted the prop governor for full take-off thrust and the gear warning horn on the throttle cable. We flew another hour and I got two more landings in since it had been awhile in GA for me. I would have added 4 more hours to the break-in except i was limited to lower altitudes and high power settings for the break-in and it was VERY windy. TAS was 176-178 on 24/24 at 3500” so I am guessing 180-185 higher. It was a rough ride. I have a fuel pump that needs overhauled so that is going out. I also have a small box in the avionics bay that controls glareshield and panel lighting that needs overhauled. Maybe one EGT probe as well. Otherwise, for the amount of work we did on the airplane……everything went well.

Well, I don’t think this is as simple as you might prefer. The evidence here falls way short of establishing the “brazen fraud” you posit. He was certainly licensed (certificated to be pedantic) as I saw nothing to indicate his cert was ever revoked. As far as the medical, I’m allowing for ignorance of what conditions require a new 3rd class medical when already under Basic Med rather than conclude deliberate malice. This guy paid for his mistake with his life, and fortunately didn’t hurt anyone else. And now you want to punish his grieving wife by denying the claim for the plane and having her pay for damage to the farmer’s field out of her pocket? You certainly aren’t punishing him!

If I read the facts in the light most favorable to the pilot here, it’s possible that he thought since his most recent application for a third class medical had not been denied, and his BasicMed was current, he was good to go. There are definitely some conditions that would require a new application for a third class and a grant via SI before he could fly under BasicMed, but I suspect that many people don’t read that far into the reg.

I would use a piece of closet rod and a vice to make the bend. Clamp one end with the closet rod. Then use a rubber mallet to help you bend it. If the closet rod is the wrong size then wood dowel. Go to NAPA and get some of the little springy things, drill a hole and insert. Then go to fabric store and buy some foam filling, some leather of your color and some contact cement (not the water based, the good smelly stuff) Cut and glue. Pilots can do interior stuff under Preventive Maintenance. Make it look better than factory and nobody will care. If you want to redo all the lower panels in leather. leatherhidestore.com Buy a couple of hides. There is different weights of leather hides.

Going through the decision process on backup AI myself. My M20 F is going in for avionics upgrades in a couple of weeks it already has a GI 275 for AI but the HSI is analog. The HSI is getting replaced with another GI 275. Both GNS 430w are getting replaced with GTN 650. The panel mounted 496 will be replaced with an Aera 660. The airplane currently has a backup AI that is vacuum driven. It is the only instrument in the plane that will need vacuum and it just recently started to precess badly so it needs to be replaced. So, struggling with what to replace it with. Another vacuum driven AI, or a digital AI so I can remove the vacuum system. If digital AI then I wanted something that will last longer than the GI 275. Been looking hard at the RCA 2610-3. At 80% brightness it will last 3 hours on its internal battery which is plenty long to get me down alone with the Aera 660 with its own 4 hour battery which I can use for navigation while he master is off. Still have not made a final decision but but leaning towards ditching he vacuum pump and installing the RCA 2610 Sent from my iPad using Tapatalk Pro

Honestly, I am not very interested in the “up to” time. That is marketing. Generally, it assumes a new battery and not one that has been in the aircraft for 5 years and many rechargings. I want to know the “down to” time, which is 30 minutes for the 275. I seriously don’t think that is the lawyers talking (caveat, I am one), that is what the engineers found in durability testing and the lawyers then said, well, you need to put it in the AFMS then. What happens if the OAT is -54 dF (have been there) and/or the battery(ies) are old? The other concern is the “system” concern. What if the system created by dual redundant 275’s, for example, develops a software error and the entire system goes to red “X’s”? Although those have been extremely rare, they have happened and some of it has been documented on this site. It got my attention. Don’t get me wrong, I like my 275’s. I love my 750. But I noticed that when certifying aircraft, the FAA insisted on building in non-single-point of failure redundancies. So in the old days, if the King 256 vacuum AI failed there was the electric AI. Not the best backup, I will grant you. But they were thinking “if Plan A goes completely wrong, there needs to be a separate Plan B.” The longer I fly the more I have come to appreciate that concept. If you own one of the 28V dual alternator aircraft perhaps you have a Plan B in the second alternator. But the older single alternator-single battery aircraft need a separate Plan B. I am not trying to pick an argument with anyone, I have met many of the people on this site and like and respect all of them. But I have had the alternator completely fail four or five times, the vacuum once, flown with the Master off and seen what there was left in the single battery when it came time to land, and flown all of these routes that I am talking about, they are not hypotheticals. I am just trying to pass on some wisdom. For the first, probably 8 years I owned my aircraft I did not have a backup AI other than the TC. I have fixed that problem in my own aircraft from advice I read on this site from other more experienced pilots. I am glad I did.

Another Mooney on the ramp in Hillsboro Oregon this weekend! A beautiful long body with tks. Definitely makes me jealous. I always miss out meeting the pilot too - he/she must have arrived after me? Real nice tailwind on the way back to Spokane. Apparently I broke the Mooney groundspeed record as well… at least my 430W thinks so!

The other day I was talking to a TBM owner at KMTN. His jaw dropped when I told him the "M" stood for "Mooney". Then I showed him the picture and recounted the history.

When IO550s were new… A bunch of Cirri and a Mooney suffered from cracked oil coolers… Drain all of the oil out of an oil cooler… and your day goes downhill at best glide speed… The Mooney reportedly landed on a golf course… There were a bunch of oil cooler replacements in early M20Rs for that reason…. Continental also manufactured the oil cooler…. Do you wake up screaming Fore!, and you’re not a golfer…? as far as ethics go… keep in mind, a Mooney landing gear up on pavement will be stopped in about 200’… As far as danger goes… avoid roads if there are fields available… a stout sign post or guy wire can cut a fuel tank open on your trusty Acclaim… getting out of the flaming wreckage may be extra challenging… Best regards, -a-

A few years ago, I found some oil in the bottom of my #4 cylinder and engine oil was fouling that bottom spark plug. I did a ring flush of that cylinder using straight MMO. Worked very well for me. I look hard at that cylinder every annual and it still looks good.

There is no need to spend that much money. The trim switch, assuming it's the one that looks like this: https://images.app.goo.gl/NPnsfxHLKxHeZdUTA Is actually made up of three switches underneath. Those internal switches can fail, and can be independently replaced. They are Honeywell 1SX74-T switches and can be purchased for about $35 each from mouser: https://www.mouser.com/ProductDetail/Honeywell/1SX74-T?qs=10P5Hhl%2BD796P7tntVKlzg%3D%3D&countryCode=US&currencyCode=USD If you look through my thread earlier this year about my autopilot issue (which was just me being too hasty) there are some detailed pictures of the wiring of the switches. You can order a replacement switch or two or three, install them, and that should fix your problem. I'm happy to chat more about this if you want.

Swift is actually saying that both peak and LOP are a no no. I read nothing compelling in that BT thread, though there is some reasoned speculation. Lycoming once again seems to be proving that their default position is to make general statements without providing supporting data. There may be a carb issue, but parallel valve Lycomings have always had somewhat more challenging cooling characteristics (flame suit on but Lycoming's cooling charts prove it). If the operators are adhering to the manufacturers CHT limits and recommendations, "mircowelding" should not be an issue. I am also dubious on the idea that detonation sufficient to cause valve recession (not something I've ever heard of) would fail to produce any of the other common issues associated with detonation (cracked spark plug insulators, deformed electrodes, ring and land damage, piston pitting, scuffing etc). Lycoming is suggesting that the recession is caused by aromatics, but 94 UL does not have high concentrations of aromatics (relatively speaking), not to mention that many, many Archers have been running on Mogas (much higher levels of aromatics) for years. The situation is as clear as mud. Hard data would be nice, but I have yet to see any analysis. UND and their propulsion engineering dept. should have been an impartial analyst collecting and analyzing data, but I have not seen evidence that they've done much of that. Maybe this will happen in the future as all aircraft were equipped with Garmin G1000, so they should have the raw data. To do this correctly, they should have had a control group and an exclusively 94UL group of the same aircraft running the same missions and then analyzed each group post trial. Instead they ran 94UL in the whole fleet of eligible aircraft and also mixed 100LL in with 94 UL during the trial (any offsite fueling was 100LL). I have seen no synopsis of engine telemetry from the trial but it looks like they are working on that. Lycoming and Swift are both "interested parties" and both should be sidelined when it comes to analyzing this less than ideal trial.