A64Pilot

They actually could afford them 50 years ago, as a kid going to the local airport on a weekend you couldn’t wash your airplane unless you got there early. Too many in line. There would be 10 pilots in one of the two FBO’s discussing the exact same thing we argue about now, like reduced power climbs and leaning it out etc. So much traffic there were two follow me trucks that would race to the taxiway vying you to follow them to their FBO, of course two full maintenance shops on the field, and one full blown Avionics shop. Full blown pilot school with a fleet of newish Beechcraft’s to train in and rent and several CFI’s on staff, They sold the aircraft and bought new about every two years, who would rent an old airplane? Same town today there is one FBO locked behind what looks like a prison fence that services the occasional Biz Jet, I think there may be one aging A&P/IA associated with it. Avionics shop is gone, no traffic to speak of on Weekends and you occasionally see some old Dr dragging his Baron out of a T hangar, no rental aircraft, maybe one or two beat to death OLD 172’s but I don’t think so. Incidentally the towns population is more than double what it was in 1970. Back then before you left to go to the airport you called the FBO and they would pull your aircraft out of the hangar and put it on line, it was part of hangar rent, when you got back they would top it off and put it away. No T hangars back then, but then you didn’t pump your own car gas either, or put air in your tires or check oil. Different, more affluent world for Joe Average There were more aircraft manufacturers doing a good business than there were Auto manufacturers. Average airplane was five or less years old, but most pilots were plumbers, electricians, house builders, Pharmacist's and of course Doctors. Price of a 172 in 1970 was $12,500, about half the price of the average house. Median price of house now is supposed to be $380,000, can you get a new 172 for half that now? If you could I bet airplanes would be selling. https://www.statista.com/statistics/272776/median-price-of-existing-homes-in-the-united-states-from-2011/ Oh, and average age of GA aircraft isn’t 5 years old anymore, it’s more like 50 years old according to the FAA, and there are only a couple of GA manufacturers, most that are still building GA aircraft make their money from building Biz Jets but still build the rare single engine piston out of tradition I guess. https://www.faasafety.gov/files/events/EA/EA68/2023/EA68121005/EA68121005F.pdf

No, and boost doesn’t raise it but a tiny bit, based on both boost and mechanical giving the same pressure readings and no operating issues as in my 19 GPH on takeoff doesn’t change pressure, I’m letting sleeping dogs lie. But I don’t like operating in the bottom of a range, since taking that photo I’ve added a washer or two to oil pressure which brought it up a little but not as much as I’d like, I like oil pressure at the top of the green

To keep the cyl head temps in the middle of the green. LOP is a reduction in power and therefore CHT temps. Attached photo is Cruise in Florida cowl flaps fully closed as I almost always cruise that way. OAT I’d guess mid 60’s F but don’t remember, full throttle, RPM probably 2300 because she’s smooth there and LOP burning 8.2 GPH. Pretty warm temps. Using the 14.9 number that’s 61% power which is all you can get at 8500 with mid range RPM, you can get more of course by going ROP, but that burns more fuel and has other detrimental effects besides just the wallet. I adjust cowl flaps to whatever opening gives me the middle of the green temps.

Just read the accident report you linked, what was the cause of the engine failure?

Mine is N1141N, ATC always has trouble with that, so now I say November eleven, forty one November, that’s easier to get your head wrapped around. I reserved my old Maule number as I had it changed to my initials when I recovered it and the other day found it available again, oddly when you search the FAA database according to them my Maule never existed. So I reserved it in case I repaint the Mooney, unlikely but it is only $10 a year, what annoys me no end is if you look up that N number it shows my full name and address, why not post my Social Security number while we are at it?

P-38 procedure for LOP in 1940 something NOTES ON MIXTURE CONTROL The engine ls fitted with a Bendix-Stromberg carburettor Instead of the usual two-position mixture control, as fitted to British engines. the mixture control has the following 4 main positions: FULL RICH: In this position there is no automatic compensation for altitude and temperature AUTOMATIC RICH: This is the position for the richest mixture which is automatically maintained by the compensating device. AUTOMATIC LEAN: This is the normd position for weak mixture. The automatic device maintains the mixture at this setting also. IDLE CUT OFF: For stopping the engine and while priming during engine starting operations. Furthermore, the mixture strength can be progressively weakened by moving the lever from the AUTOMATIC HIGH position towards the IDLE CUT-OFF position, the weakening being effective also in the region beyond the AUTOMATIC LEAN position up to the point where the IDLE CUT-OFF operates (at the extreme end of the travel). At any point in this range the automatic compensating device is in operation. Although placing the mixture control in the AUTOMATIC LEAN position gives a considerable reduction in fuel consumption, it is possible to obtain a consumption of about 5% lower by adjusting the mixture control as follows: 1. Obtain the desired engine cruising conditions 2. Change the airscrew control from AUTOMATIC to MANUAL. In this position the airscrew becomes effectively a fixed pitch airscrew 3. Set the mixture control to the position determined by weakening the mixture until a drop of 40 to 50 R.P.M. is indicated. The position may possibly be between AUTOMATIC LEAN and IDLE CUT OFF 4. Return the airscrew control to AUTOMATIC If changes in altitude or cruising conditions are made, this setting should be checked by repeating the above operations.

There is a triad to most efficient, full throttle because it reduces pumping losses, it’s one reason why Diesels are so efficient, because there is never any vacuum in ones manifold, even at idle they are at full throttle, as there is no throttle. Best BSFC which is normally LOP, a stock Diesel is always LOP, because it’s throttled only by fuel flow, get one ROP and it smokes heavily. Then lastly very low RPM to reduce frictional losses. The toyota Prius is an exercise in operating efficiently, it can’t go LOP due to emissions, but it’s very common for the Prius computer to be running the car at 1200 RPM or so and full throttle, the Prius PSD or transmission if you will can vary RPM over a wide range, so it’s computer would run the engine full throttle and dial the RPM down until power developed matched demand. It did other tricks too of course. Pumping losses are real but minuscule. Try it yourself, climb up decently high (say 10 to 12 thousand or so), go full throttle at low RPM, then increase RPM significantly and reduce throttle until airspeed matches the first test point exactly, give several minutes for it to stabilize, you guys with Autopilots have a real advantage, but compare fuel flows, the lower RPM should be lower due to both greater prop efficiency and less engine friction, so operating high MP and low RPM is more efficient, that was what Lindbergh went to the Pacific theater to teach in WWII, incidentally the P-38’s POH had a procedure to lean to LOP, they just didn’t call it that then. Maybe it will work in a Mooney, but when I ran the test points in a Maule it really didn’t make much difference, there is increased efficiency, just wasn’t as much as I had hoped. I say go up high in order to be able to stay with the factory chart limits of not being too oversquare, but look at your charts perhaps you won’t need to go so high

It’s 75% power in a Lycoming, not 65%. It’s 65% power in a Lycoming for max engine life, or do you guys think Lycoming doesn’t know what they are talking about with this too? Its tough to exceed 75% power above 5,000 ft running ROP, do you guys think you are LOP? Or do you do cross country flights down low?

I’m hoping for at least two manufacturers and an established track record. Competition seems to drive both quality and cost. I know want in one hand etc. In the Military there was a saying, “never fly the A model of anything”. I flew an A for years, later the D model, the D really was much more reliable, so maybe there is something to that saying. I don’t expect any magic, hopefully reliability and decreased inspections

I know that and thought I had explained that adinfanitum Point I try apparently unsuccessfully to make is if you stay within those numbers you are protected if you make a mistake is all, because as you say those numbers are safe for ANY setting. I guess too just ignore that Lycoming says for max engine life to fly at or below 65% power too? Anyone is free to do as they please, years ago I was taught during a risk analysis class the most conservative response rule, that is when faced with more than one possibility, choose the one that’s less likely to get you into trouble. It’s in everything, some push fuel, argue that you don’t have to land with the reserve just have planned to have it. Most conservative response is land and re-fuel. Those that are arrogant enough to believe they are better, that they know what they are doing, that they don’t make mistakes can of course operate as they please.

It’s difficult to near impossible to get an O-470 LOP, some have said if they run short of WOT that the partially closed throttle plate causes enough turbulence to atomize the fuel enough to do so, and some have said if you run some carb heat that helps too, that they can barely get LOP. I’ve never tried myself. But you can pretty easily operate one just rich of peak without any tricks Sometimes we just never know, my guess is it was likely pre-ignition and of course many argue that pre-ignition is always the precursor to detonation, but does it matter who’s on first? From an owners perspective you still end up with a big bill, so does it matter who shot John? What matters of course is how to prevent it in the future, there are many ways to get into detonation, it can be as easy as forgetting to go rich before going full throttle to climb etc.

The max CHT’s are just that, Max. The engine manufacturer has to demonstrate that the engine won’t destroy itself at those numbers, not that it won’t suffer from significantly increased wear / stress etc. Lycoming in several places has printed for max longevity to run 400F or LOWER CHT. and I think the max on Lycoming is 500 F, so they want you running at least 100F cooler than Max for long life. Remember Cyl temp is an indicator of stress the engine is under it’s not just cyl head temp, it’s other components as well and of course hot heads is one of those things that significantly reduces detonation margin, unless you find yourself in a box canyon or something and have to climb at Vx or similar to clear terrain there is no need to operate at high cyl head temps. Get into the habit of cruise climbing, that is at much higher speeds than Vy and you can keep cyl head temp in the middle of the green most days. The generally accepted percent power where you can’t hurt a Continental with mixture is 65%, Lycoming it seems has a greater margin of 75%. 65% and 75% does not mean that if you operate higher than those numbers LOP that you will detonate, those numbers just mean if you operate below them and make a mistake and allow the engine to enrichen that your mistake shouldn’t be a costly one.

If your ROP and descend yes you are getting leaner the more you descend. However if I’m over 75% power in a descent of 500 FPM or higher my J model will exceed VNE, so it’s unlikely to say the least that many descend at over 75% power I would think, plus obviously the higher airspeed results in much cooler cyl head temps than climbing, so it’s very unlikely your going to get into detonation in a descent However most climb at the highest power available, that’s the difference

The helicopter cylinder and piston, they tried to polish out the damage then wisely gave up. He wasn’t attempting LOP ops, I doubt any helicopter guy would attempt that. He thought his fuel burn was excessive so they leaned the fuel servo out based on an internet expert. Luckily when it started making noise at a hover they started looking, they thought collapsed lifter, I thought maybe stuck valve, but it was detonation, of I guess you would call it “light” detonation.

I think there is more mis-fueling possibly than we realize and or fuel contamination Apparently as the new fuel trucks require DEF, it seems people are putting DEF into the Prist tanks. https://www.ainonline.com/aviation-news/business-aviation/2019-05-27/def-contamination-downs-two-citations I remember taxiing an R-1340 Thrush over to the Albany Ga FBO telling the kid to top it off and as we are standing right in front of the big ole 9 cyl Radial he says these things take Jet, right? At least he asked, I never thought I’d have to specify. My private airplanes, I’m the only one that is allowed to refuel them. Not saying that’s what happened there, who knows, maybe an intake leak, pre-ignition point whether carbon or piece of metal, maybe a damaged plug? I assume it was not running car gas?

I don’t disagree, if your let’s call it truly LOP you can’t detonate. The issue as I see it is you have to maintain a pretty narrow EGT range, once you get say -50 or so LOP power falls off of a cliff, it’s safe just slow. Then there are engines that will run LOP but just barely, my newly overhauled with new Millenium cylinders IO-540-W1A5D with Gami injectors and new fine wires wouldn’t run any deeper than -10 or maybe -20 LOP before it got rough, so it’s margin was even smaller. It didn’t take a whole lot to put it into a mixture where detonation is possible. That’s why I preach to run at a power setting that no matter what you can’t get into detonation. Maybe it’s just me, but I occasionally make mistakes, be flying for awhile and realize the boost pump is on, I’ve even found myself trimming out in cruise to discover the flaps were in takeoff position. As I said all it could take is a slight climb without re-leaning to put yourself into a mixture that you could detonate, and I know if I fly long enough that’s one of those mistakes I’ll eventually make and I’m past the point of gaining experience, I’m at the point where every year in truth I’m not as good as I was the year before, for over 30 years I flew professionally, nearly every day I had Wx. Now I’m doing good to fly twice a week, but I’m determined to fly at least every week.

Lift table would probably be out of my price range, but I’m hoping to find a good wheeled cart to put things on as they are removed. Every now and again people age out or die and there is a hangar sale. I want some jacks, I made some out of pipe stands but they need work To add to the wish list, a Big as in 48” or so floor fan, mine came from home depot, and just the opposite, some form of heat. I have two of the kerosene heaters that look like a jet engine and sound like a blast furnace. a little one and a big one, Leave quite a bit to be desired but the bigger one puts out a huge amount of heat and will heat the whole hangar. I run Jet-A in the thing, seems to stink less. I’ve been told ULSD burns clean too, but am hesitant to try because the old Diesel didn’t and would ruin one. I only use it a few times a year as the real cold days in Fl you can count on your fingers. I define cold as below freezing, I know others think that’s warm.

In my opinion the only issue with a (D) magneto is it’s becoming more and more difficult / expensive to have one overhauled and seemingly few of the younger generation of Mag specialists are taking them on, every year it seems the number of shops decreases. That’s why I’m rooting for an electronic replacement, not because I think there is anything wrong with a (D) mag just it seems to be headed to the orphanage. I just hope what happened to ADSB will happen to them, that is they will become less expensive, but maybe not. Another opinion of mine is slippage marks are fine, but I think during oil changes develop the habit of grabbing it and trying pretty hard to make it turn, it shouldn’t of course.

I don’t know who else but I do. I keep thinking I need to try the bungee trick, but keep forgetting. I think it would work better than the chair. I’ve got one of those Da** mechanics stools on wheels that slides out from under you if you just lean in the thing. I need to throw it away, an overturned bucket would be better than that thing.

You changed what I said tremendously adding what you think. The gist of what I said was that it’s possible to hurt the engine if your attention is somewhere else at high power and the mixture drift towards rich, like say be overwhelmed getting IFR reroutes and be assigned a higher altitude How many have harmed their engines from detonation, I’d say hundreds, maybe more in the last year, my Brother detonated the IO-520 to death in the C-210, and my neighbor detonated a cylinder not to death but enough to have to replace it on his new Helicopter IO-540. That’s two that I’m personally close two. In fact that’s the only piston engine damage that were family or close friends. However if my Brother had been lower power it wouldn’t have happened, but he was trying to keep up with me in a 1,000 HP crop duster. The helicopter, well they can’t really fly at low power The gist of what I said is that you can’t hurt one by running any mixture below 75% power in a Lycoming, so why take the risk of attempting LOP above that? Why even try to cruise above that? For those that money isn’t an object sure cruise high power and replace the engine as necessary, but if money is no object, why try for high power LOP? When in fact if your LOP it’s not likely you can actually get high power, for high power you want 100 ROP. Ref why cruise at lower power, see attached, you do so for greatly increased engine life, ANY engine if run very hard doesn’t last nearly as long as one that isn’t. 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. From here and other places, this is just the first Google hit on https://www.lycoming.com/content/leaning-lycoming-engines#:~:text=For maximum service life%2C maintain,Oil temperature – 165˚ F. The reason I post these things is for those that are new enough etc to be asking questions on a forum. I try to give them info that they won’t hurt their engines, then later if they decided they want to go further they can. My Brother didn’t know what he was doing, the helicopter guy was following some internet experts advice, cost my Brother a new engine, the helicopter guy just a cylinder, he got lucky. Both had engine monitors, both first sense of trouble was an unusual noise, My Brother thought the gear were “thumping” the helicopter guy heard a rattle, thought he had a collapsed lifter, replaced that etc before finally borescoping it and finding damage

CHT closely follows power output, a reason CHT drops as you go LOP is due to the power drop. Depending on how you label high power, high power isn’t possible LOP or of course we could takeoff and climb LOP. Be foolish to do so but full throttle LOP is possible, significant drop in power and there is risk, but you can do it. Don’t, because you could get yourself in trouble trying, best BSFC is just a bit LOP, roughly -20F, which isn’t much, enrichen just a tad and then your running full throttle at peak, which I think most agree could get you into detonation, and that could be a $50,000 oops and or a forced landing. Personally the biggest reason for me to run LOP is efficiency, and you get even more efficient by slowing down. I cruise LOP almost always, usually at 8 GPH, yes that’s quite a bit off of full throttle, but I burn even less fuel than a Piper Cub or my C-140 as a function of fuel mileage, and it’s not just a little bit, it’s a whole lot less. It’s surprising when you run the numbers. At 6 GPH I’m 50% faster than a Cub in a four place airplane burning about .5 GPH more, but that’s slow even for me. I don’t have an analyzer in this aircraft, I have before but the way I fly I don’t need one, it’s s misconception that you have to have one to run LOP, you don’t, just be sure to stay below a power setting where you could cause damage, which is something that I think you should do anyway. Stay South of 10 GPH, for me well South and yiu can do anything you want to with the red knob and not hurt the engine. I’ve become risk adverse in my Retirement, the cost benefit analysis of high power LOP just isn’t there for me.

LOP power calculations are pretty easy, because power is purely a function of fuel if your LOP knowing an engines efficiency to calculate the power produced you just multiply fuel burn by let’s just call it the efficiency number, for our angle valve 360’s I believe that number is 15, so 9.4 GPH x 15 = 141 HP which is less than 75% so you were safe. As 75% power is 150 HP it stands to reason if your LOP any fuel burn up to 10 GPH is safe, above can be but you can make a mistake and cause damage, below 10 GPH and at least in theory you can’t. Still always watch CHT, open the cowl flaps if needed. That number isn’t hard set in stone as of course higher RPM has greater frictional losses and there is only one LOP setting that achieves the greatest BSFC etc, but if I’m correct and our number is 15 it’s close enough, you can get deep into the weeds for sake of argument, but your splitting hairs LOP power is a function of fuel flow because if your LOP that by definition means there is excess air available for combustion so fuel flow is the limiting factor. Oh and I may be misremembering the number as I cruise well below that as I’m seeking efficiency and willing to sacrifice some speed for it, so I’m. ever near the limits. It’s really tough to make a case for anything but LOP cruise assuming you’re cruising at low power anyway. Only time ROP is really called for is down low where high power is possible or if your in a hurry and time is more important than efficiency, or maybe at very high altitude where LOP just can’t make enough power, you have to go to best power to get up there. At least in a NA engine people want to argue that you can go just as fast LOP as you can ROP but it’s not true, highest power is only at one mixture and that’s best power mixture, any mixture other than it is less power.

I don’t really have an exact definition of red box or red fin or whatever, but I know detonation is not primarily a function of mixture, it’s more predicated on possible ignition sources like too hot a heat range plugs or carbon or maybe an exposed tang of a helicoil etc (yes I know these are pre-ignition but as the result is essentially the same does it matter)? In the cockpit you can’t tell the difference. But also MP and just plain on how hot is the combustion chamber (cyl head temps) So in other words it’s sort of like the fire triangle, you have to have all three for a fire. To get into detonation and engine damage you pretty much have to have all three. A mixture that can support detonation, an ignition source and a high enough power setting to enable it, although power setting and heat are very closely related. Heat in itself can be considered an ignition source, pure detonation doesn’t require a hot “thing” but heat alone is enough, think Diesel engine where heat from compression along with very low octane fuel is enough. So often detonation is caused by requiring high power to climb over those mountains or whatever that results in high cyl head temps that are aggravated by slow climb airspeeds like Vy for example and the coffin nail could be the pilot who doesn’t want to spend the couple of GPH that actually may be so rich that it slightly decreases power and has nothing but negative results, except that it keeps cyl head temps down. Lower RPM increases the likelyhood of detonation, remember how the 70’s cars would ping on a hill but if you pushed the pedal down causing a downshift the pinging would stop? If and this is an arguable point, but IF you keep cyl head temps below 400F on a Lycoming IO-360 it’s not likely you can get into detonation period, not in a normal world climbing to a cruise altitude or at a cruise altitude. However the extra 2 GPH or so that pretty much guarantees you can’t get into detonation if you run that mixture for 10 min and fuel cost $5 a gl then it cost you $6. $6 per trip is a cup of fancy coffee, pretty cheap insurance, I say 10 min because I don’t care how high or how long your climbing, after the first 10 min of climbing your power is down so much that it’s likely you can’t get detonation from mixture anyway Plus the lower cyl head temp you get is less stress on the engine and less stress will result in longer at least cyl life, and most of the time people measure engine health by cyl health. I’ve almost never seen rod clearance measured when cylinders are removed to see how much bearing wear there is. This is of course assuming no one mis fueled you with Jet or your not trying to run car gas or something

Sometimes, but not always. What your saying of course is “you get what you pay for” which is not always the case, more and more things are sold that are grossly overpriced including services and as always a lot of add ons are sold, that very often drive the price up with very little value. This is true with pretty much everything so in order to protect yourself you need to have more than a basic knowledge of the product or service you’re purchasing. I know quite a bit about somethings and insurance is not one of those things, so I basically have to rely on what seems logical, but I do know enough to understand that’s a poor knowledge base. In short I’m the furthest thing from a subject matter expert when it comes to insurance, in fact I’ve pretty much avoided insurance as a rule. However I know of several instances where the ambulance chaser refused what seemed to be a guaranteed win based solely on the the person at fault either had no insurance or very low limits. I believe in lawyer speak they were “judgement proof”. I think their first step is to ensure that payment of a large judgement is viable, if it’s not they don’t pursue the case, because of course it’s a business and they exist to make money, not to help people or ensure justice is done etc. So it seems logical if during discovery they discover you have a very large insurance policy they would sue as opposed to almost none and your assets would be difficult to get, it would seem that maybe the best way to protect yourself is to do whatever you can to protect assets and that a large insurance policy could possibly increase the likelihood of you being sued and possibly you lose your assets as well as the policy amount. Maybe we are better off with just the legally required min insurance? This from a Retired perspective as I think my Mil Retirement, disability and Social Security are difficult to get which just leaves primarily Retirement savings to protect as I think the house is also safe, Mooney and other vehicles aren’t I don’t think enough to get them excited

From what I’m understanding of your question your last sentence is key. No as long as your operating within OEM specs you shouldn’t be hurting anything. I have zero turbo experience but it’s my limited understanding that it would be very difficult to be at a harmful mixture setting detonation wise that wont have you exceeding TIT, perhaps turbo operators will chime in. It’s my limited understanding that TIT is your limiting number mixture wise. But again surely those with turbo experience will chime in.