A64Pilot

Can you have those Honed? If not then you might be better off letting sleeping dogs lie. Between Chrome, Cermichrome and CermiNil I get confused

I’m with you. As I have a tailbeacon, the lights are on all of the time, and I guess it’s three years later they still work. However I think that new aircraft should be all LED, and good quality LED’s will last a very long time, but to spend the $$ that they cost to replace the old incandescent? You just don’t get anything for the money from what I can see. Low quality LED’s are noisy, so noisy that they can interfere with Comm / Nav equipment. I put inexpensive LED lights in my hangar, they are so noisy that they break squelch on my radios. So if you buy LED’s from Ebay, Amazon or whatever they could cause a problem. The USCG check procedure only checked Comm freqs of course not AIS etc.

It’s been years since I had my CC with the Verado, back then they only had inline 4’s which I had and an inline 6. The 6 was smooth as glass as an inline 6 is better balanced than a V8, it reminded me of the old Tower of Power way back when. The Verado was a much better engine than a Yamaha in my opinion. My boat couldn’t handle the weight of the inline 6, I was slightly underpowered with only 175 HP because it was outfitted as a dive boat so we always carried at least 6 dive tanks, usually 10. I’ve been happy with my 4 cyl IO-360, it’s smoother than I expected, four cylinder swinging a two blade prop I expected more vibration than I’m getting, and it’s frugal which I like. From memory I think between 10 and 12 thousand running WOT at 2200 50 ROP I burned 12 GPH with the 235 IO-540. It just wouldn’t run LOP very well, actually it would run like -25 LOP but if I ran the exact same speed ROP it just wasn’t much fuel savings. I’ve not bothered trying that test with the Mooney, I’m convinced the engine I have is the poster child for LOP, where the 540 just wasn’t. I was stationed in Germany for a tour, hence the name.

I understand why the engine was derated. The newer Cessna 182 that used to have the 230 HP Conti 470 now has a 230 HP IO-540, to increase the HP would be a whole new Cert program that may have required changes, but one 230 for another 230 is easy. The reason why hasn’t got anything to do with its life. There are 2 235 HP 540’s. One is low compression and carbureted, it turns 2700 maybe RPM to make 235 HP. The IO 235 is both high compression and fuel injected and therefore only has to turn 2400 RPM to make 235 HP. Take that motor and turn the RPM up to 2700 I think it is and you have the 260 HP motor, the 260 motor doesn’t have the reputation of extreme long life that the IO 235 does and the IO 235 motor lasts longer than the carbureted 235 one. The 300 HP motor is significantly different, you can draw correlations with it but as it’s not identical it’s not an apples to apples comparison The point is that by reducing power output and RPM, the life of the engine is increased. Don’t get caught up in the weeds, these are generalizations. De-rating motors is extremely common in everything from Outboards to Diesels to turbines, without exception that I can think of the de-rated motors last longer. Your right it’s to only make a couple of engines cover a range of power, Mercury with its Verado engine covers from 150 HP to 350 I think it is with only two motors, the difference being the motors computer.

Up to you of course but up there I’ve been at full throttle, heck by 10K I’m abandoning LOP too. 10K at LOP mine is a dog. Excepting for cloud clearance I don’t fly that high anymore. For most people as we age our tolerance for altitude decreases. I think by 10K to keep from getting fatigued etc at 65 I probably ought to be on O2, and that’s a PIA. I used to spend hours higher than I was supposed to and it didn’t bother me, but then I could run 2 miles in 12:30 too, where now I couldn’t run out of a burning building

Those charts are at best power? LOP is significantly lower power output, one reason to cruise lower power is reduced fuel burn, so surely your LOP. I believe it’s pretty simple if I understand. Forget the charts, to be at 75% power for our angle valve motors LOP you have to have a fuel burn of 10 GPH. If you turn middle of the green RPM that’s going to require more than 25” MP I believe, and the general rule of thumb is 1” MP loss per 1,000 ft, so the highest you can pull 25” on an average day is 5,000 ft. Do LOP cruise charts exist? Is there even a need? 10,000 ft you can only get roughly 20” MP so to keep power up requires both higher RPM and best power mixture. That rule of thumb isn’t linear of course or otherwise you would be in space at 30,000 ft, but it’s close enough for us low altitude guys. As we are talking engine longevity RPM is tied to wear, actually it’s piston speed and that’s why one motor can run higher RPM and not have high wear because of its stroke, where a longer stroke motor can’t. But anyway within limits reducing RPM will reduce wear. But within limits, as a general statement higher RPM wears on the valve train while low RPM with corresponding higher load to maintain HP wears on the pistons, cylinders and bottom end. If you keep MP the same and accept the power loss then lower RPM increases engine longevity. The Green ranges are of course the points where the engine manufacturer expects if obeyed an engine will make it to TBO, those of us that are working for an even longer life if we run closer to the middle of the green ranges it’s likely the engine will last longer. The IO-540 line is a very good example, those motors range from 235 to 300 HP, there are differences of course but the 235 is to a great extent mostly a de-tuned if you will 540, de-tuned primarily by lowering the RPM limit, it’s max RPM for example is 2400 RPM. I prop struck mine years ago and as it was right at TBO and as I’m an A&P/IA I chose to overhaul it for resell reasons. I sent everything off of course, but every single wear item I sent off was still within NEW limits, not serviceable but new. That motor would likely have gone to twice TBO is my guess just by following the Lycoming mandatory SB replacement items required on major disassembly. I’m not saying don’t cruise at higher RPM if you choose to, but primarily by turning the RPM limit down to 2400 RPM max Lycoming hugely increased the life of the 235 HP IO-540. Why didn’t they increase the TBO beyond the 2200 hour current limit? Who knows, I don’t. Its green range was 2000 to 2400 RPM. I usually cruised at 2200 being in the middle of the green. For those that worry about being oversquare, the IO-540W1A5D engine I’m talking about at every sea level takeoff pulled 30” MP at 2400 RPM, that’s pretty seriously oversquare, but it was the factory setting. So being oversquare within limits won’t kill your motor. Everything has the within limits disclaimer of course. It’s my opinion that cruising within the middle of the green will give you the longest life, avoid continuous operation at the extremes, either high or low. Higher altitude will most likely require higher RPM or the engine just can’t make the power, sometimes yiu just gotta do what you gotta do, best power mixture and high RPM to not hit the ground in places.

To continue 8 GPH at 23 squared gives me 135 kts which is 16.9 MPG 6 GPH at 21 squared gives me 120 kts, which is 20 MPG, but 120 is usually too slow for me, and 3MPG just isn’t a big enough number to matter to me. Maybe if I had to push range though. Climb higher and run 155 kts at 10.5 GPH gives you 14.8 MPG, but I’ve found that I burn more climbing than I realize so unless it’s a several hour flight I don’t. Just for grins a Legend Cub’s book cruise speed at 75% power is 82 kts, an O-200 will burn about 6 GPH which gives the Cub 13.6 MPG, the Mooney J model gets better fuel milage than a Legend Cub at any cruise speed. My C-140 flies at 91 kts burning 5 GPH which gives it 18 MPG. I’ve not checked any lower speeds and the fuel burn is a SWAG as it doesn’t have fuel flow, but I’m sure it could match the Mooney at 20 MPG.

Unless you’re willing to run max governed RPM it’s likely lower than we think. I like to pick an RPM that’s close to the middle of the green myself but one she is smoothest, you can feel what smooth is by holding the glareshield. Smooth is gentler on everything avionics included. I too am lazy and as I don’t have to cross mountains and don’t do O2 anymore I always fly LOP so being lazy I use the 1GPH = 15 HP. It may not be exact, but for me it’s close enough. 8x15=120 HP and 200 div by 120 = 60% power. So I fly at 60% power almost always

Of course some will tell you that Lycoming doesn’t know anything about their engines, but below is their recommendation for maximum engine life, personally I wouldn’t run higher RPM and low manifold pressure, I’d pull the RPM back, but not so low that it vibrates. Of course keep things in the green, if you can’t keep cyl head temp in the green, increase power or enrichen the mixture. I always cruise LOP, probably more LOP than ideal, I’ve found adding 1/2 GPH in mixture will bring the cyl head temp right back up. Even in Fl on a Fl cold day I can’t keep cyl head temp in the green at low power and LOP sometimes. With any engine there are people that will tell you that they are designed or meant to be run hard and if you don’t you will kill the engine. I don’t know where this idea came from or why it’s so persuasive, but it is, even sail boat engines. The geared motors were hurt by high MP and excessively low RPM, by lugging if you will, people just couldn’t get it into their head that they needed higher RPM than direct drive motors. One engine design even drove the prop off of the Cam so of course the prop turned at 1/2 engine RPM. Good idea because it didn’t need a gear box, but it had lots of unrelated problems. I personally very rarely cruise above 65% power myself, I’m usually around 60 ish. 8 GPH gives me 135 kts indicated down low, plenty fast for a 20 min trip to eat Breakfast. So long as you keep everything in the green the motor will be fine, Once broken in its very difficult to glaze cylinders, what usually causes them to glaze even in break in is high cyl temps, not necessarily high cyl head temps, but cylinder. Best way to overheat the cylinders is extensive ground ops, and new, tight cylinders due to friction get hotter faster. Glazing is exactly what it sounds like and it’s high temps not cold temps that will cook on a glaze layer. It’s literally a varnish type of coating that clogs the cross hatching. Lycoming has this stated in more than one of their publications. For maximum service life, maintain the following recommended limits for continuous cruise operation: Engine power setting – 65% of rated or less. Cylinder head temperatures – 400˚ F. or below. Oil temperature – 165˚ F. – 220˚ F. ‘This is actually the full quote, interesting that they give numbers that apparently don’t match the book for max engine life. I’m sure they are much lower numbers. During normal operation, maintain the following recommended temperature limits: Cylinder head temperature – limit listed in the Lycoming Operator’s Manual. Oil temperature – limit listed in the Lycoming Operator’s Manual. For maximum service life, maintain the following recommended limits for continuous cruise operation: Engine power setting – 65% of rated or less. Cylinder head temperatures – 400˚ F. or below. Oil temperature – 165˚ F. – 220˚ F.

Honestly that’s nothing, EVERYTHING has to be replaced from the alternator, starter, engine mount, exhaust system, prop, every engine instrument and likely some extensive fuel system mods, pumps etc. Tanks ought to be fine, we used the same fuel tank sealer for turbine crop duster used in the Avgas Mooney’s. You ought to look at the Diesel Maule Certified about ten years ago to see a huge very ugly very high drag looking cowl, so who knows? https://www.planeandpilotmag.com/article/diesel-maule-alternative-energy-for-the-boondocks/ It would truly be a very extensive mod, and people will argue this but you are rolling the dice, we honestly don’t know what may happen given a few years and thousand hours, airframe or mounts cracks, who knows. I’d like to see it happen it hopefully would dump lots of serviceable “stuff”, props engines, exhausts, every accessory into the used market.

I used to cave dive every weekend, dove in a dry suit because believe it or not but after a couple of hours 68 degree water is COLD, freezing shivering cold in any wet suit. As we dove dry we wore Condom catheters attached to a tube that led out side of the suit, Condom cath’s have an adhesive that after a couple of hours sometimes was really tough to remove. The few Women that dove wore “She-Pee’s” basically a funnel that required close shaving and was glued to them. https://scubadelphia.com/products/she-pee Compared to that peeing in a bottle is nothing, I’ve even successfully peed in a coke bottle, it’s tough and you really have to pay attention, but it can be done.

If you have the inside of the wings sprayed with Corrosion-X every few years you can just about forget about corrosion at least in the wings anyway. From what I have seen Mooney’s aren’t well corrosion protected in the build, anything you can do is likely worth doing.

Deflecting beam is believe it or not but most accurate, doesn’t need calibrating but is a pain to use. Last one I had I think I was 15. I’ve never used a “digital” torque wrench, what does it do that a click type won’t? Digital is most often marketing, usually the device isn’t digital of course just plain mechanical / analog with a digital display, most can’t read the vernier scale on a micrometer so I understand the attraction, I admit to having a digital caliper but it’s so I can change back and forth to metric and standard, just keep a spare battery in the box. What could be easier than a click?

I do think you hit the nail on the head, for whatever reason, maybe it’s just coincidence but it seems just about everything that can be done to drive down energy prices is now being done, we are pumping more Domestic oil than we have EVER done Maybe the decision to not export LNG was a green decision as it was being reported, even though NG pollutes less than most, but by not exporting that means Domestic supply increases, which drives domestic prices down. Energy of course is a HUGE influence on the economy, cheap Energy = strong economy. However where I live the price of Auto gas has increased a little, not continued to drop like I expected. Winter blend is cheaper than Summer blend too, and of course we are burning Winter blend now. I paid $2.87 I think last week, now it’s almost $3. Local Sam’s club, cheapest around for me. Gas prices Unleaded 2.98 9 10 Premium 3.23 9 10 Diesel 3.66 9 10

High wings have several advantages, chief among them is it gives you a place to stand when it’s raining, and they almost always have two doors and are easier to get into and out of. High wings are less likely to be damaged if flying bush, easier to camp out under a high wing. People have always said they are more stable, but I don’t think that’s necessarily true. The one thing that annoys me about them is you can’t see in the direction you’re turning, if you turn left you can’t see to your left, the wing is in the way. That’s the one reason why in my opinion they don’t make a good Ag plane. Its way easier to make a low wing retract than a high wing too.

1 Pics below are of my Balmar VR mounted on the outside of the engine enclosure for longevity reasons and of the alternator set up. I was running 660 AH of Concorde’s deep cycle AGM bank, not Lithium back then, back then you had to DIY Lithium or NiMh and if you did your insurance Co would cancel on you. Fire at sea is worse than sinking so I didn’t consider Lithium myself. LifePo4 was fledgling technology back then.

On boats most stock alts are internally regulated, it’s not hard to bypass the internal regulator and install a good programmable three stage external regulator and most replace the stock alt for a higher output anyway, and go from a single V belt to serpentine because 60ish amps continuously is about the limit you can get from a single V belt before it begins to slip. One thing is important to bring up, and that’s duty cycle, it’s very rare for an alternator to be able to make rated power continuously without overheating, and normally they don’t have to, watch your ammeter after start, see how quickly it begins to drop, even if your lead acid battery is pretty much dead. However most modern Automotive vehicles have gotten pretty sophisticated with the alternator being controlled by the vehicles ECU, even the Alt output is controlled to assist in emissions testing, so it’s tough to do like it’s done in boats, hence the inefficient DC to DC charger that also gives up one of the LifePo4’s major advantages, fast charging. But as “drop ins” do exist now, called drop ins because they are just that, prior to them if you went to any Lithium based battery you have to heavily modify your charging system to both protect from overheating the alt and to protect the alt if the batteries BMS suddenly disconnected, which normally fries the alt. immediately, and of course to protect the battery from overcharging. But anyway as drop ins do exist, only one of two possibilities exist, either the drop in protects from over amping the alt during charging and has a way to protect the alt from a BMS disconnect, or many alternators are being fried. I don’t really know as I haven’t dropped in a LifePo4 in anything, I put them in my golf cart, but I bought a specific LifePo4 charger too, so they weren’t dropped in. Only thing I’m trying to bring up is that merely replacing a lead acid battery with any Lithium chemistry isn’t as simple as simply replacing the battery, there has to be protection systems somewhere, either in an additional black box maybe or I guess that black box could be built into the physical battery case. With boats, Motorhomes, Golf Carts you can buy stuff from Amazon or Ebay and do as you please, with Certified aircraft there is the FAA of course, but every now and again the don’t always get it right, Mobil 1 Av oil for example. I’m highly suspicious of the Earth -X only having half the reserve capacity of a Lead Acid battery myself. The primary purpose of the battery isn’t to start the engine, but to supply a power source to ge you safely on the ground should your primary electrical system pack it in. I’m risk adverse, when my Concorde dies, I’ll replace it with another. Concorde doesn’t talk much about it, but they have been building Lithium aircraft batteries for the Military for quite some time, why they haven’t for GA or if they ever will I have no idea. They have been guilty of spreading misinformation in the past that I’m sure that they knew better. like playing up the fire danger, which isn’t a factor with LifePo4. I’ve attended seminars and heard it myself. https://www.concordebattery.com/about/concorde-lithium-ion-aircraft-batteries.html

My biological bladder may not even support the range of my 54 gl fuel bladders. I’ve been flying with this for the last 20 years or so, this one is called a “Little John” When I was ferrying aircraft I used Gatoraid bottles. 12 hour legs were common, so I ate beef jerky and drank Gatoraid and refilled the empties.

I have a tail beacon, and see no need to “upgrade” Why would you want to? ADSB in is easy and inexpensive without having to spend big $$$ on installed equipment too and often even has a built in battery back-up.

1 Depends on the Tesla, older models like my 2021 Model 3 have s regular lead acid I believe AGM battery, Tesla “freaks” change them for LifePo4, I don’t know why. Newer Tesla’s come with LifePo4 little batteries I think. Tesla has a whole how to DIY section in the manual. https://service.tesla.com/docs/Public/diy/model3/en_us/GUID-2588F809-41E3-43F1-84E5-6745C7C18DBE.html

I understand that and it’s done that way with most charging of large banks like my 660AH bank of Lifeline batteries in my boat would cook an alternator, so the voltage regulator monitored alternator temperature and reduce field voltage to keep it within the temp limits you set. I could only get 80 amps continuously out of a 165 amp alternator without it overheating But these are airplanes and that would mean certification of a VR with temp sensing, and for multiple aircraft with multiple different alternators, so ain’t gonna happen. So that means it’s going to have to be internal to the battery. I wouldn’t expect the battery would need more than 10 amps of charging, leaving the rest of the alternator capacity to run the aircraft, it might not even need 10 amps. I’m not sure how it’s done in Motorhomes, but I know current limiting of the alternator is required for LifePo4 conversions, has to be. I think using a DC to DC charger, no reason I can see to not have that as part of the battery. If I understand it you install say a 10 amp DC to DC charger, that limits max current draw from the alt to 10 amps. I pulled 10 amps out of the air, it’s certainly higher for bank charging. Is a DC to DC charger a buck convertor? I have no idea. Stuff’s magic to me. If you really want to know about LifePo4 drop ins and what’s possible, this is the smartest guy I know on the subject, Yes this is a boat site, but a real cruising boat lives or dies on its battery bank, or more truthfully the difference in being comfortable and camping on the water is your battery bank. The whole Lithium battery “thing” for boats is about 15 years old, they pushed the technology because they had the most to gain, to a great extent LifePo4 addresses all the shortcomings of lead acid. On edit, but it’s only one thing that needs addressing, a major concern is what happens IF the BMS opens and disconnects the alternator? I assume our current VR’s shut down prior to reaching 14.6V? https://marinehowto.com/drop-in-lifepo4-be-an-educated-consumer/ Point is the technology to limit amp draw from a Lithium battery exists, and has been fielded, but I sold our cruising boat and moved ashore right in the middle of the great plague, so I’ve lost data on where we are with “drop ins” now, they didn’t exist when I swallowed the anchor.

So far as wrong generalization. ‘Read the last line of the apparent Kromer article, that seems to be a pretty generalized statement to me. I’d quote it but the software won’t let me.

I slip my Mooney whenever needed, but that’s not often. I slip the snot out of my C-140, it’s one Cessna that slips are OK, because it has regular flaps I think is why. If your trying to spot land slips are a great tool, because you can vary the descent rate easily Slips are a very effective method of losing altitude without gaining airspeed, Slips used to be very common but you don’t see them being taught much anymore it seems, I don’t know why, perhaps more Modern aircraft aren’t allowed to slip? Cirrus and Diamond etc? I don’t know. There is a LOT of training going on where I live, fly to Deland and try to sequence in between the Embry Riddle students. From a glance I think training is different, you just don’t see the nose high land on the mains with the nose in the air that I was taught ever, most often you see three point or maybe the nose a little high but still touches down at the same time as the mains. I was taught that the nose wheel was for taxing, not landing, but the 152’s that I learned in I think have weak nose gear too. I think slips have gone the way of spins, they I don’t think are taught anymore, because I never see any of the trainers doing them, but then I’ve not noticed even one soft field takeoff either, but I’ve not sat and watched them, maybe they are but I don’t see it. I think the emphasis is on teaching Airline drivers now, and they don’t slip, spin or do soft fields I guess.

You and I are within a lb or two of each other. In my opinion and take that for what it’s worth is that a J model is the ideal two person traveling machine, but and this upsets people when I mention it but AK FSDO for example regularly or used to anyway grant a 10% overload exemptions for single engine 135 ops that requested it, maybe not now, my data is a decade old, but anyway they have done so for years and if there was a negative safety impact surely they wouldn’t. Now as I understand it, that’s 10% over gross weight, not a 10% increase in useful, and that’s a pretty big number. I wonder if they still do? If faced with pushing fuel or being a little overgross, I’m going to be overgross, worrying about fuel sux, just don’t. I’ve landed someplace to find the fuel pump broken too, I stop wherever gas is cheap, and that’s almost always small airports with one fuel pump, having plenty of gas to go on to the next airport saved the day. Besides I think it best for the tanks to remain close to full anyway, if you do, what’s the plan to defuel for the trip? When calculating baggage I at least always carry a can of windshield cleaner, quart of oil, jumper cables and tie downs and a tow bar as a min, and that stuff adds up. Often I carry a small tool bag with tools (shaving kit sized bag), nothing excessive, silly tie downs are heavy though. The Claw I think it’s called, 8 lbs maybe? It’s actually pretty easy and not all that expensive to ship your baggage to where you’re going, had a friend that flew Airshows in a Pitts that did that. He loved it, said having the heavy luggage in his room when he got there was priceless, He carried a wallet and a small bag with necessities in case of bad Wx or maintenance. Much better plan I think to ship a suitcase and carry extra fuel. But take this in the manner it’s meant, meaning trying to be helpful, but at this time in truth you really don’t have a clue as to what you need, you think you know what you want. The difference in travel time between a Mooney and a C-172 over a 300 mile trip is measured in minutes, it’s not a big number, much longer trips is where it begins to matter, and the fuel burn is likely more than offset by cheaper maintenance costs. If you shop around and buy a good fixed gear, fixed prop airplane and keep it for a year or two and get your instrument ticket, you will be able to sell it for what you paid, your insurance will be much less expensive and you’ll have a much better idea of what you need, and a much better idea of what’s a good deal, and now since your hanging around the airport and have met several fellow pilots if they know your looking for a Mooney they will tell you about any that may be coming up for sale. Often that’s how you find a deal, inside information. Weight wise a 180 HP 172 will haul anything my J will as will an older 182. 182 isn’t fixed prop but still it’s easier than a Mooney, more forgiving and I’m sure insurance is easier. I’ve seen some good deals on older straight tailed 182’s and many will tell you the straight tails fly better, I think so anyway. But take one of those and put a couple hundred hours on it in two years and it’s likely it will sell for more than you paid for it, old airplanes if flown regularly and decently maintained don’t depreciate it seems, most have flown little in the last couple of years and they don’t sell well because of that, but put a couple hundred hours on it and it will sell for more. Finally I’ll warn you that an old complex airplane no matter how well a pre-buy was done has the likelyhood of getting real expensive, fast, often at the first Annual. Ideal is when you have your first beginner airplane you find an A&P that lets you do the grunt work, de-paneling, washing, repacking wheel bearings, you know the dirty work and leave him to do the inspecting. I’ve been told that will save you a lot of money, and makes owning an older Mooney much more affordable so long as you don’t mind getting your hands dirty. I’m abdicating you to ease into this is all. I’ve seen it beak many people is all, and in truth we all run the possibility of finding $50,000 worth of metal in our oil filters, don’t think that doesn’t keep me up at night at times. A rental? That’s their $50K problem, not yours

You only “need” a slip when coming in over tall obstacles and need to get down, slip of course increases descent rate without increasing airspeeds. Speeds then are WAY less than 80 kts at least in a J and that’s being heavy with near full fuel and 100 lbs in the baggage compt. I think my touch down speed is high 40’s maybe? Honestly I haven’t looked, touchdown is when she quits flying in ground effect with no float of course and elevator is near full travel The hundred lbs in baggage does hurt acceleration on takeoff, but other than that I don’t think it’s hurts performance, if anything it seems to cruise slightly faster, not slower and landings are easier not being nose heavy. No one can argue that 100 lbs doesn’t hurt take off and climb, but I think the trade off is worth it. Please if you’re going to practice short field landings and I think we all should, be comfortable with go-arounds and don’t try to salvage a bad approach. It can get expensive. Grass is fun, if you cut out grass fields you’re cutting out a whole lot of fun, country laid back flying, lots of EAA fly-ins etc happen at grass strips, But then I’m the type that would be miserable living in a City, the once or twice I’ve done it we were young and I didn’t like it. Many grass field are as smooth as pavement, and if you fly off of grass your brakes last a long time and you change tires when they dry rot. Tires just don’t wear on grass and I don’t think you can flat spot one either, but you really shouldn’t need much braking on most grass anyway. However at least in Fl there is sand and that does wear on the prop, I don’t go full throttle until I’m past 20 kts, but you can still tell there is erosion on the prop.