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Ahhh...yes. The universal "it is for the children" argument that we are all supposed to buy without questions. By the same respect, it is morally or ethically acceptable for any airport governing body to allow or mandate sale of a product that has been misrepresented as "safe" while causing damage to aircraft? I guess it is, so long as it is "for the children".

The passenger seatbelt is a regular as well…

Hello all, After a rough couple months of spam-bot invasions I have decided to make some critical changes to the way new users to the community are validated and how Supporter level memberships work. Here are the key changes: When a new account is created here it will be placed in a group called Unverified Members. This group can browse the site but cannot create any new content. To upgrade this account to a Verified Member you have two options: a) pay a $2 fee for instant validation which is good for the life of the account or b) contact me @mooniac58 with a picture/scan of your valid ID to prove you are who you say you are. The old manual $10 minimum donation for upgrade to Supporter level has been replaced with a $25/year automatic subscription system that will renew every year on its own unless you cancel it. No more waiting for me manually upgrade your account, etc. Those that purchase the $2 instant validation will get a $2 credit towards their first year of Supporter level access...so $23 for the first year and $25 thereafter. Generic Donations: Separate from the membership plans, users can still donate arbitrary amounts to support the site using the new donations page. Those that donated prior to today with the old system will continue to have Supporter access until 12 months from your last donation as long as that was $10 or more. These are the current membership levels for members: Unverified Members - New accounts, can browse site, cannot create content or message others. Verified Members - Either paid the $2 fee or proved in another way that they are a real person. Can post new content but not in classified forums. Limited to 200MB total storage for attachments, photos and other files. Supporter Members - Signed up for $25/year subscription. Do not see advertisements on site. Able to post non-commercial topics on the classified forums. Storage limit of 1GB. Sponsor Members - These accounts have paid a fee to have a limited number of commercial posts on the forums (usually 1 per month limit). Some final notes: While I am confident new spam-bots are not being registered on the site, I am quite sure that they have dormant accounts that were created in the past that still exist undetected. For this reason we have and will see brief uprisings where they rise up and make a bunch of spam posts. We will ban each of these as they occur and wipe the content. I don't expect much of this and the past few days have been clear skies here. If you created an account prior to August 5, 2025 and did the normal email based activation then you are in the Verified Member group. No one was downgraded during this process and you don't need to do anything to validate your account. Please do not do the $2 validation process (I am still working on hiding this option for everyone except unvalidated accounts in the site). I will be making small changes here and there to try and make it more clear how new users validate their accounts. For now I hope newly registered members find their way to this topic to get the instructions. Eventually I hope to figure out how to customize the site more to guide new members through the process better. And lastly a big thanks to everyone who has supported this community over the past 17 years! Craig

Had one of those moments only a Johnson bar owner can appreciate….ALWAYS check the floor before raising the gear! I relearn this about once a year. Today could have been ugly, gear wouldn’t go up…..WTF?? Look down and realized I had smashed an errant port-a-john. LUCKILY it was empty!!!! Quick gear cycle verified bar was fine and time for a new urinal. Johnson Bars and Port-a-John’s are not compatible, despite their names.

I believe there is a movable (vertically) weight rigged to a bellows of sorts. When you climb or descend the force of vertical acceleration compresses or expands the bellows and provides an instantaneous increase/decrease of pressure vs. the delay caused by the calibrated leak in the case.

That looks great! This was the Great Southern Haze Layer last weekend, coming from NC back to Sweet Home

Flew to our place in CO for Labor Day weekend. Mt Humphrey's by Flagstaff High Desert Ship Rock KPSO landing in light rain

Before you start tearing into things, try getting a large Gats jar and push up all the way to fully open the valve and get lots of fuel out. Do it several times. There may be some gunk under the seal which will clear out with a substantial draw. I've found most people don't pull enough fuel out to fully flush the valve on a regular basis. Do it several times to see if you can clear any gunk under the valve seat.

Finished installing the GeeBee seals. First off, after reading all the previous descriptions of issues with seals I was apprehensive...but in hind sight I think this was unfounded. I installed the new profile (larger bulb, less durometer) on both baggage and main. New GeeBee (left), Old GeeBee (middle), Mooney seal (right) Cleaning off the old seals: Baggage door seal looked different than the cabin door. Baggage door was the foam core rubber seal, but the main door was dense crunchy foam seal. Baggage door came off cleanly and way too easily, but the cabin door came off in chunks. The money was to use plastic razor blade scrapers to scrape off the foam between the rivet heads and get down to adhesive. This worked surprisingly well but was a little tedious in places. Main Baggage I used cheap thin plastic drop cloths from Home Depot with some painters tape to mask things and keep any remover or parts off the paint and out of the aircraft. It was an easy step that made clean up super easy! I took off the interior panels for both the doors. I initially removed the hold open arm on the main door, but it really didn't open that much more and I think you could easily just leave it on and be fine. But it makes it a little easier. If you do take it off, be mindful of the washers and the cotter pin when removing. Hold open arm parts: Door Cotter pin AN380-2-2 (MS24665-132); Washer AN960-10; Washer AN960-10L I then used white shop terry cloths (and a brass brush as needed) with a small spray bottle filled with Adhesive remover. Given the fumes I'd recommend good ventilation and a respirator/glasses/gloves. Depending on how thick and crusty your old adhesive is, dictates how much you need to use a brass brush. Some have described using drill mounted brass brush, and I found that I could control the use of a brush easier without worrying about damage to the underlying frame by hand. Being able to spray the adhesive and keep it wet as it softened the adhesive made it MUCH easier. With softened adhesive sometimes using the corner of a terry cloth rag dipped in some adhesive remover pulled off the top layer of the glue and that coupled with a brush turned it into about an hour+ per door. I think the 3M General Purpose Adhesive is less damaging to painted surfaces than other types of removers. I think overall it worked well and I had no damage to paint or any surfaces inside or outside the aircraft...although I did mask with drop cloths very well. Ounce of prevention is worth a pound of cure. 6-pack of cheap plastic drop cloths from HD Plastic Razor Blade Scraper 3M 08984 Adhesive Remover Small 2 oz spray bottle Wood handled brass brush After cleaning off the old adhesive, I used isopropyl alcohol to clean off the metal, cleaned up the drop cloths/area, and reassembled the hold open arm and reinstalled the door panels. To prepare for door seal install the next day, I remasked using painters tape along the back edges of the doors to protect the paint from glue/from clamping. I threw a clean moving blanket over the wing walk and wing around the main door to keep things off the paint and prevent paint drips on the wing. QUICK ASIDE: I debated using the 2-part silicone cement that GeeBee includes based on comments here on MooneySpace about something like 3M 08001 yellow "gorilla snot" that has "more working time"...THIS WAS COMPLETELY UNFOUNDED. First off, you can't use rubber cement on a silicone seal...so don't even try to use 8001 on a GeeBee seal. But I've used gorilla snot and it's stringy, messy, and goes on way thicker than you need. I think the cement GeeBee includes is Momentive SilGrip PSA529 & SRC18 Silicone Contact Adhesive. And a huge shout out to Guy as he has this packaged with mixing stick, measured bottles, a pipette for mixing small amounts, and even paint brushes to apply...its clear, just the right consistency to lightly apply just where you want it without running or dripping, and is SO much easier to use than 8001. If you're apprehensive about using GeeBee's cement...don't be. That's just silly. BAGGAGE TIPS: For the baggage door you want to install so that the "tail" of the "P" seal goes on the raised part of the door ~right around the edge of the door panel. You want to make sure you have enough exposed metal at the edge as there is a slight profile at the edge that will bind if you put the seal too close to the edge of the door. Also, by putting the tail on the raised section, it allows you to easily and smoothly turn the corners. The part closest to the hinge (top of the baggage door when closed) should be close to the raised section away from the hinge. So basically on the baggage door it's easily to follow the tail along the raised part lined up with the edge of the interior panel. Make sure you put your seam at the BOTTOM OF THE DOOR which is the higher part when you have the door open. MAIN TIPS: Get inside your aircraft and use a thin pencil stuck into the gap in front of the hold open arm. You can use a pencil to make a mark along the bottom frame of the aircraft to see where the seal should go. You can't quite get the entire bottom marked with a pencil, but you should be able to get enough to see the idea of where the radius of the door frame goes. Along the sides and top you want to center the "P" bulb roughly on the rivet heads, however you want to make sure that when compressed that the seal doesn't flatten past the edge of the door frame. Take a look at your door frame and it should be obvious where you want the bulb to hit the frame. Really the only tricky point is really at the front lower corner due to the gap from the hold open arm. If you followed the interior panel the seal would be in the gap and not sealing anything. With a pencil mark you can aim to have the edge of the tail at the pencil line to make sure the bulb is contacting the frame. Then once you turn the corner you can again align the bulb with the rivet line. I mixed up the epoxy into a small "baby food" size container that I got a 4-pack from Target. Take a small piece of seal to see where you need to apply the seal. So use the paint brush and apply a THIN layer of adhesive on the frame where you're going to put your seal. If you're doing both seals, then I'd suggest starting with the baggage door, then main. So apply thin layer of adhesive to the frame of the baggage door, then apply to the main door. You can use a hair dryer to "speed up" the drying. What I'd suggest is apply glue to both, then only use hair dryer on the baggage door and the main will dry while you're applying the baggage seal. Use isopropyl alcohol to clean the seal. Then start at the BOTTOM of the door (high point when door open) and apply a thin layer of adhesive on the seal tail up to the bulb (just the part that will lay flat). Use a hair dryer to dry until tacky. Then place the seal TAIL inside / BULB to the outside. Extra points to apply the seal end between rivet heads so that each end will glue to flat metal instead of right over a rivet. If you're at a point where you can apply glue to the hanging seal you can apply to 10" of seal and dry. But slowly apply the seal when the glue is tacky and press firmly to adhere. I used small clips from Harbor freight (I bought 2 x 22 piece packs and it worked perfectly) to hold the seal as I moved along, but with the adhesive properly tacky the seal will hold itself. When I ran out of clips, I'd harvest from the initial clips placed and move the clip train along the seal. The adhesive is pressure sensitive so press the seal firmly and it will hold. When you get back to seam, cut the end of the seal LONG. Then slowly cut a little at a time until it requires very slight compression to fit. This will allow you to join the ends together with cement. Then move to the main door and make sure the adhesive is tacky...if not, you can use the hair dryer, but I'll bet you'll take at least 20 min standard dry time to apply the baggage door seal. Clean the seal with IPA. I started on the bottom of the main door and worked towards the hinge. That allowed me to follow the pencil line and turn the corner. Then it was smooth sailing to follow just inside the rivet line. HINT: you don't want the center of the bulb closer to the edge of the door than the center of the rivet line. Basically when the bulb is compressed, you don't want it extending past the edge of the door. I think mine were actually centered on the inside edge of the rivet line. On the main door with a moving blanket on the wing, its easy to keep the seal laying on the bulb and apply adhesive in a longer length of seal. But still apply to the door in 3-5" increments and press firmly to adhere and then use the clips. Once the seals are in place, go back though and make sure the seal is firmly pressed to the door after you've removed the clamps. Then let cure with doors open for 12-18 hours. The next day is the moment of truth. If you closed the door prematurely, you could possibly glue more of the bulb seal down to the frame than you need. I applied a thin layer of silicone lube/paste to the seal, wiped off the excess and then closed the door. Firm, but not cumbersome. Seals well all around. If you need a new seal, I wouldn't hesitate to use the seal and kit from @Gee Bee Aeroproducts. I was way more apprehensive about this than I should have been. But give yourself a good 3 day stretch to make sure you have plenty of time to finish and take your time. Day 1 clean off old seals, clean up and reassemble interior panels. Day 2 to apply new seals. Day 3 lube seal and close, then leave in the sun to fully dry and cure.

I flew up to Rotterdam where the street art is off the charts. The biggest challenge of Rotterdam is pop-up thunderstorm cells. I studied the weather, and studied and studied. Everything said stable weather the whole time. Then the morning of departure, boom! Pop-up thunderstorms at both ends of the runway. Luckily they disappeared as quickly as they came, so it's wasn't a big deal. I don't have too many pictures of the flying, but here is one, plus examples of the super cool street art with one work in progress

A long time ago I instructed in a C-150. This was in the days where 80-87 had just gone away and the O-200 was not happy on 100LL. We just a bit of MMO in the fuel after having some valve sticking and it did not have issues again.

Due to the significant pitch up when flaps are retracted in Mooneys, especially the long body Mooneys, I have taught to retract the gear 1st, trim down, then retract the flaps when going around. I always taught the student that the drag of both were comparable. While most POHs say retract the flaps 1st, in this case I think safety is more important in my opinion than an incorrectly written POH. Finally, in the Acclaim Type S the POH does have the gear being retracted before the flaps in a go around. I recently saw a YouTube video of a recent test conducted in a Bonanza on the given topic. For the Bonanza the conclusion was that the flaps should be retracted first. I decided to run the test on my airplane, a Bravo M20M. At 4,500 feet I slowed the plane to a steady 105 knots ( 5 knots below maximum flap extension speed), engaged the autopilot in altitude hold mode and extended the gear. The plane stabilized at 87 knots for a drag reduction of 18 knots. I retracted the gear and returned to a stabilized 105 knots. I then extended full flaps and waited see where the airspeed would stabilize. It stabilized at---87 knots, the same as with the gear extended. Demonstrated conclusion: Confirming my earlier statement, for safety reasons, the gear should be retracted while trimming down before the flaps are retracted in a Mooney go around.

From the service manual

These things rock! Got us above the thin smoke layer across Oregon and northern Nevada. Yes it took 17,500’! But she’s real fast up there. Got to see Burning Man too. 6 in the pattern on adsb as we went by - no thanks!

I dumped it into a 2009 Outback filled with sludge in @2021. It was leaking a bit of oil and thus I never changed it over the course of 4-5 yrs and maybe 20K miles. Driving from ORD to ATL it blew all the crap out and the car leaked like a sieve because of all the sludge being gone. Mechanic put some gaskets and other junk in, said it was a really clean looking motor. Still running though I try to change the oil at least once a year now (it’s down to maybe 1k miles a year now). Testament to Subaru and Seafoam in my book. YMMV.

I knew you would come around.

ACK! As Bill the Cat might say? I’m thinking transponder, and writing ELT. I plead late night induced sleep-surfing. Thanks for the correction, I’ll change my post for clarity and will try tp do better in the future.

The whole returning dirty oil to the engine is nonsense. The oil mist / vapor that goes overboard is no different than the oil in the crankcase, it’s not dirtier. Every modern automotive engine I can think of has a separator in its PCV system, because of course you don’t want the engine induction system getting liquid oil into it. Automotive engines haven’t dumped blow by overboard in what maybe 60 years? I’ve seen no difference in oil analysis on engines running separators from ones that don’t. Don’t you think Blackstone etc would have raised a flag years ago if there was? Having said that neither of my current airplanes have them, I’m lazy and cheap, I just clean the oil off once in awhile with mineral spirits. I know some aren’t even allowed to wash their airplanes it seems, if I were that guy I’d probably want one. Some perfectly Airworthy engines blow oil out, some don’t. Wrt pumps are “better” in that they are extremely reliable, and last as long or longer than the engine, but they do pump out an oil mist in their exhaust, it’s not an excessive amount, you don’t have to run a separator but it will increase a greasy belly if you don’t. Oh, wet pumps are bigger and much heavier and more expensive than dry ones.

External ELT antennas are not only very common mounted on the upper fuselage, that is where I would expect most owners would want them (unless you would prefer landing inverted off-airport).

If you didn’t own the aircraft and didn’t hire the shop directly to perform the annual then it would not have been your annual but the sellers with no need to communicate anything to you. Very possibly the screw interfering with the aileron tube was added by the shop doing the annual if there isn’t much damage to the tube. as a new inexperienced owner it’s too bad you didn’t use Savvy Aviation to manage your pre-buy and annual as you would have gotten good professional advice to avoid these mistakes. Too late for that now but you can contract with them for the QA service which is a consulting service to help you with your next steps. See SavvyAviation.com for details. Sent from my iPhone using Tapatalk

Looks like a sellers annual. Did the shop know the seller?

My often repeated trick was unbuckling my belt when I lowered gear. My wife got good at rebuckling me while I flew the plane.

It works very well, thank you. It was in the Mooney when I bought it.

When I had my M20F, I had one of those Sportys E6B electronic calculators. I kind of missed that thing.

antenna length = wavelength = speed of light / frequency. So a UAT antenna: 299792000 / 978000000 = .3065 meters or 306.5 mm or 12.068 inches. quarter wave is then 3.017 inches. That's why those transponder antennas are so short. Apparently quarter wave antennas perform well omnidirectionally and are easy to make.

Here are some insights of go arounds with larger airplanes: If you fly an Airbus 320 or a Boeing 737, during a go around, always the flaps are retracted first by one step or to a certain position. Then the gear is retracted after the positive climb is confirmed. With the Airbus A320, the call of the pilot flying would be "go around, flaps". Then the pilot monitoring checks the speed and retracts the flaps by one step and confirms the action. Then the pilot monitoring checks the attitude and the climb rate + rising radar altimeter and calls for "positive climb". Then the pilot flying calls for "gear up". For example, if we land an Airbus with full extended flaps, it is a flap setting which is never be used for a takeoff. Retracting the flaps by one step brings the plane in the same configuration which may be used for a normal takeoff. So, retracting the flaps first brings the Airbus into a known takeoff configuration. My Mooney M20F manual does not say anything about go arounds. It looks like that 1967 no go arounds were flown.

We installed overhauled J model senders from Air Parts when we installed bladders this year. We made sure we had good wiring, new gaskets, new insulators, good grounds, etc. They work great now. No bouncing. No jitter. They even work well with the original fuel gages. I have an EDM-730 for everything else.

At 45 knots, my wheels are firmly on the ground, whether taking off or landing. I'm usually landing around ~72 mph = 62-1/2 knots over the numbers, and almost never with full flaps, in a continuous deceleration towards the ground. Then full throttle is just another takeoff--i.e., positive rate, gear up then flaps up, except it will require more down trim than a normal takeoff due to trimming nose up on final.

Another thing that happens when the gear is up is the gear doors and the wheels plug the big holes under the wing. That helps a lot with climb, which is desirable on a go-around.

Since the discussion is about antenna suitability for an application, it's the BW of the antenna that matters, not the signal, and whether the carrier frequency of the signals of interest fall within the usable BW of the antenna. We know that all of the relevant signals are relatively narrowband compared to the carrier frequency and antenna passband, so the signal bandwidths aren't really relevant other than they're narrow enough to fit in their assigned channels and not interfere with each other and therefore fit in the antenna bandwidth. e.g., transponders listen on 1030 MHz and transmit on 1090 MHz. ADS-B uses 978 MHz (only about 8% off the center of the 1030-1090 pair, and only about 5% from the 1030 MHz interrogating signal). ADS-B also uses 1090 MHz, which is right in the band of interest for the transponder antenna. The antenna would have to have a fairly (unexpectedly) high Q to attenuate the 978MHz signal very much, so it should work pretty well for listening to either ADS-B frequency. The bandwidths of any of those signals don't really matter, just their carrier frequencies. DME uses 960-1215 MHz, which covers all of the ADS-B and transponder frequencies, so a DME antenna should be suitable for listening to any of it. Many suitable antennas with TSOs are shown as being interchangable as either transponder or DME antennas. Again, the signal BW doesn't really matter, just that the antenna response BW is wide enough to cover the desired applications.

I have 500 hours on my 3 2019 servos, no issues yet FWIW.(knock on wood)

Everybody on here is always trying to get that last 1% of performance out of every aspect of their plane, and now they are espousing using a sub optimal antenna when a shiny new one is $150 bucks and two minutes to change it out.I don’t get it…. You are going to spend that much for the new coax and connectors.

If it isn't visibly corroded or damaged there shouldn't be an issue. If the shop has a Vector Nework Analyzer (VNA, they're not expensive these days), the antenna can be electrically tested to see if there are any issues. Many shops don't have those or don't want to test such things since they can sell you a new antenna otherwise.

I agree with Don. The avionics shop probably wants to start with all new parts because it reduces any chance of issues with existing components. The antennas are not very expensive and once you select a shop it's best not to tell them how to run their business. But, the OP asked if replacing the antenna was necessary and the answer is no, if it is working correctly.

The install manual for my GTX 345 states that the antenna is considered part of existing equipment and that any antenna approved toTSO-C66() or C74() is acceptable. We reused the original King antenna from the KT 76A and it works fine.

I installed one in my Cessna. I replaced the transponder antenna with a RAMI antenna. It was reasonable. The problem isn’t old and crusty, it is the old antenna doesn’t have the bandwidth to handle both the transponder and ADS-B signals. https://www.rami.com/product/av-74_transponder/

If you believe that, you might also want to replace all your nav/com antennas as they also have BNC connectors. But if your BNC connector is truly "crusty" with visible corrosion, then that's a different matter.

My experence is retracting the flaps will reduce lift and the airplane will dip a bit. This isn’t something I want during a go around. Especially close to the ground. I don’t touch the gear or flaps until I have a positive rate of climb and have climbed at least 100 feet. That usually isn’t a problem, by the time I’m done messing with the power and trim, the plane is already climbing and I can do the flaps and gear at my leisure. Another reason to do the flaps first, is that is where your hand is, right by the flap switch. Move your hand from the throttle to the flap switch and then up to the gear.

Fantastic report for Our Prop Guy! @Cody Stallings thanks for sharing… Best regards, -a-

Shhhhh . . . don't tell Cirrus. They'll ban its use in their aircraft immediately, for "not compliant with the STC" . . .

Needed to get a flight in today to keep my streak going for flying every week. Today was week 49, just three more to go to hit my goal of 52 weeks. Short hop from FUL to POC for some breakfast in between some small cells pushing through the area.

I have J model that had a 3 blade Mac on it. It always had a lot of vibration despite being balanced by the previous owner. It started leaking a lot of grease and was going to need an overhaul. I had Stallings put on a 2 blade hartzell top prop and sold the 3 blade. It was expensive but it is smooth as silk and I gained 6-8 knots in cruise depending on altitude. Also had an A plus experience with Stallings.

Gotta love the weight and balance on a Mooney! We’re going camping in Bandon, Oregon on the beach. Try packing for camping with two adults and two kids! Fit exactly 120 pounds in the back, and the weight and balance is still good! There’s a second kid under that towel in the backseat. And although the weather wasn’t great, and we had to shoot a circling approach close to minimums to land at North Bend, we weren’t upside down either.

Craig, Very solid plan and thank you for your stewardship of this great resource. A thought: is there any way to limit visibility of existing member info (stuff on profile, tail number, etc) when viewed by unverified members? Just a thought in that spam accounts could be used to get info for later spearphishing. A few members have described scams where the perp was more knowledgeable. Minor attack vector, I hope, but worth a thought. Thanks, David

Bunch of Washington based Mooneys got together for lunch at Yakima yesterday. 5 of us showed up and we parked next to a resident Mooney to make it 6! Good food at Reno’s by the Runway, but it’s mighty warm in Yakima this time of year and there’s not much indoor seating!

This x100. This is just shakedown, it’s normal, even if it’s frustrating. at the end you will know your airplane better, and you may be able to help someone else later experiencing the same problems. Don’t give up!

These airplanes have been flying for 55 years and no accidents recorded. Now an immediate grounding and then 100 hour inspections? The ones I have seen in photos with the problem should never pass an annual inspection regardless of the AD. If someone has one of these subject to the AD with absolutely no sign of any degradation because it has been properly painted and sealed why subject it to this SB every 100 hours? Galvanic corrosion will only occur if an electrolyte can get between the two dissimilar metals. It can happen anywhere dissimilar metals are attached without adequate sealing. It happens in a variety of places on airplanes but is an AD required or just adequate inspection and maintenance? Are they going to allow owners to inspect these since there is no disassembly required to simply monitor for cracks and chips they describe and show in the SB? I wish somebody had moderated this a bit before it got issued.

tl;dr - I have had two impulse couplings destroy themselves in less than 200 flying hours, resulting in 1 and now more than likely 2 engine IRANs. Background: I had my Mooney M20J's IO-360-A3B6, equipped w/ Slick 4372 and 4370 magnetos sent for major overhaul in January 2024. It returned to service in March 2024 and had 110 trouble-free flying hours, with no adverse symptoms. In fact, we flew to Alaska and back, and everything performed perfectly. Engine ran like a top and barely used any oil and leaked not a drop for 110 hours. In July 2024, when starting up the engine at my home field self-serve pump, I heard a strange (very loud) whirring sound that I thought was an electric fuel pump sound at first (which should have been and was off, as in a normal start). The engine ran very poorly so I shut it down. After some simple investigation, we found pulling the prop through revealed the impulse coupling was very messed up. Rather than click-180-click, it was click-click-click. My home shop removed the left magneto and discovered that the impulse coupling had destructively let go, destroying the magneto drive gear, damaging the accessory drive gear(s), and rained metal debris into my accessory case, resulting in the engine being removed for IRAN and sent back to my engine shop for a warranty claim. The engine shop dutifully performed an IRAN under warranty... and apparently the magneto shop (QAA), paid for this labor, since they were the provider of the magnetos during the major overhaul. After some delays, I was back flying in October 2024 with a freshly IRAN engine and a replacement (still QAA) Slick 4372. Due to some electrical issues (unrelated to this), I have only been able fly around 80 hours since. Fast forward to this week. As I write this, I am in South Dakota and my Mooney is at KRAP. I started up the aircraft, and it ran fairly poorly. (Although without the loud whirring sound as before). A quick magneto check revealed that the left magneto was DEAD. Engine totally dies. Shut it down and inspected. On a hunch, pulled the prop around by hand. NO impulse clicks at all. Shop on field took a look and we quickly removed the magneto to find... utter carnage, again. Photos attached. It appears that the rivets failed in the impulse coupling and the pawls became stuck at high speed and the whole unit destroyed itself, breaking off large, thick metal chunks and again damaging the gears. I am at an utter loss. How could this happen again in so few flying hours. Is there anything on the engine side that could be causing this? Could a drive gear be misaligned or wrongly-sized or putting side load on the magneto drive gear or something? Looking at the accessory drive gears I see absolutely no way this should affect the impulse coupling but again I have no idea. This is getting into serious money now and nobody has any ideas what the hell might be going on here.

I heard the entire situation while flying from KSAC to southern California. I heard 85U depart Los Banos, check in with NorCal, and then for over an hour try to coach the crippled Cessna to a better resolution. The pilot(s - names broadcast on ATC but omitted here) in 85U were incredibly calm, thoughtful, and appropriate in their coaching, guidance, and recommendations. The pilot of 03H (name broadcast on ATC but omitted here) was also calm, focused, and determined. After a series of electrical system (breakers; autopilot; master switch) tests were performed, all pilots involved became confident this was a mechanical problem. Listening to this was one of the most helpless feelings I can describe; knowing that another aircraft launched in the hopes of helping the situation was heartwarming and instilled a great sense of faith in the commitment of our aviation community. The end to this story was tragic. After more than 25 years of flying, this is one of the most difficult days I can recall. Blue skies and tailwinds to the aviator of 03H and to the kind souls of 85U.