General maintenance cost: 6cyl + CS prop vs 4cyl fixed pitch

allPrimes

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allPrimes
I think I know the answer to this question but thought I'd ask the POA hive mind.

I'm at the early stages of aircraft ownership research and with (roughly) identified mission in hand, have started doing more research into C182s and 180hp C172s (and other hot-rod 172s). For me and my mission, a hot-rod 172 fits the bill really, really well.I've read here and on other forums that "the 182 is just as economical as a 172; you just have to dial the throttle back." That's all well and good and is totally fair, but what about the overall maintenance costs? I just don't know if I need to be carrying around all of the capabilities of a 182 for what would amount to likely 5-15% of my expected annual flights.

There's some brief discussion in this thread about the mx cost differential between the two and a user in a thread on backcountrypilots.org suggested that overhaul of a CS prop is just silly high. Is there anyway to get an estimate of how much mx costs on a 182 would be compared to a hot-rod 172 on an annual basis? For the purposes of this thought experiment, assume that both aircraft are in relatively good shape (for their age).

Is it a fair assumption to say that routine maintenance would 50% more for a 182 than a 4cyl 1872? 25% more? I don't expect exact numbers but would like to get an idea of proportionally, how much more in mx costs could you expect by owning a 182 vs. a 4cyl 172?
 
As long as nothing breaks, routine maintenance shouldn't be dramatically more. But if you have to get into overhauls, or even replacing cylinders, you are going to encounter significantly more just because there is more to do. Just going from 4 to 6 cylinders gives you 50% increase in potential cost for pulling and replacing cylinders.
 
Your cost per hour would be a bit higher, as you need to have a larger engine overhaul fund as well as something to cover the overhaul of the CS prop. And you’re burning 33% more fuel per hour.

If you are OK with the slower speed vs a Skylane - the 180 Skyhawk sounds like a great choice. Really the Skyhawk should have had the 180 all along. You can actually put 2 people in the back seat, climbs great, etc.

I prefer it much more to the normal 160 Skyhawk.
 
Nobody in their right mind owns a 182 so they can be "just as economical as a Skyhawk". They carry more, climb better and can travel faster. That comes with some added expense.

There may be 2 more cylinders and a more complex propeller, but there's still only one airframe. So the costs are not proportional to the number of incremental cylinders. We have one 180 hp 172 (an SP I think it's called?) and a much newer 182 in our fleet of 16 airplanes in our Club. The 182 seems to run roughly 25%-28% more than the big engine 172.

However, it is difficult for us to compare directly. Our 172s log about double the hours every year (~900 - 1000) as the 450 to 500 annual hours our only 182 logs. Because we are at altitude (4000 ASL) and because we fly so many hours, we routinely get close to 3000 hours (sometimes more) on our Skyhawk engines before overhaul. The old 182 we had (O-470 powered) would never do that. We don't have enough experience with our recently purchased Lycoming powered 182 to compare.
 
I am probably spending more on my new to me CS prop right now (overhaul) than I spent on regular maintenance in my Archer over 3 years. That Archer was very economical.
 
NRG has a good point to build on. The more things you have the more risk you’re taking.

A CS prop is a higher maintenance risk than a fixed pitch. A bigger Skylane engine will not only certainly cost more at overhaul time - but if something goes wrong before that time chances are it will be more costly that a smaller engine would be.

And it looks like you can get a 180 conversion a bit cheaper than a Skylane would cost you - they seem to have gone through the roof.
 
If you can afford the slightly higher cost of capital for the 182 VS the 172 than the slightly added MX expense will not even be noticeable to you. Overhauls are once every 2000hours. Really not that frequently and constant speed props arent exactly mx hogs. Don’t overthink it seriously. If the 182 is affordable to you then there is no reason to get 172. One last thing.. there are no hot rod 172’s... people around here love to exaggerate the added mx expenses of retractable landing gear, constant speed props, turbos, ETC. Ive owned a F33a bonanza for about 3 years now and the retractable landing gear and prop have not needed a penny of service. All the mx expenses I've had are the same things you will see on a 172. Failed voltage regulator, new battery, magneto, tires, brakes. If the purchase price of a 182 is affordable for you than get the 182.
 
I believe you CAN run a 182 $/hr for the same cost as a 180hp 172. The question is will you (and if so, why the heck would you, especially if you paid for the right to do so).

Your routine annual maintenance will not be materially different in aviation dollars (p*ssing dollars anyway).

BUT, when the 182 mill or prop needs extra work, that’s when it’ll be in a totally different ballpark. You can do your best to control or avoid non-routine maintenance but you can’t avoid it entirely if you own and run it long enough.
 
I think you will have well over twice the engine-prop expense with the 6 cylinder/csp combination compared to the 4 cyl fixed pitch, especially when you consider fuel. With 50% more moving parts and heat producing cylinders, and complexity of the CSP, the 182 definitely more expensive. The more cylinders an air cooled engine has, the more problems. The air frame maintenance should be the same. Check the rental rates for 182/172.
 
Outside of regular Mx which is more or less on par with a 4 cyl fixed pitch. The major difference would be time for a new engine. Depending how many more hours you have until TBO, you might figure an extra $15/hr into the bank for the engine.
 
It really depends on what you consider routine maintenance. The C182 will likely cost a little more, probably less than 10% though. Screws, nut, bolts all cost the same. Air filters, tires and brake linings are about the same. Looking at routine items, if you fill the sump on oil changes then you're putting in 50% more oil and that's $32 more per oil change. Say three oil changes a year so that's about $100 more. If you opt to replace spark plugs, 4 extra which is about $120 more if memory serves. Annual inspections cost about the same.

From an operational expense standpoint the C182 will burn at least 3 gal/hr. more. You can offset this a little by burning ethanol free mogas. The O-470 is lower compression than the O-360 so it can burn lower octane mogas which is easier to find.

TBO on an O-470 is 1,500 hrs. TBO on an O-360 is 2,000 hrs. An overhaul on an O-470 runs about $9,000.00 more than an O-360. I have never had a prop overhauled but it sounds like that runs about $4,000.00 for CS prop. Fixed pitch props don't get overhauled unless they are damaged, but I was quoted about $800 to overhaul mine. I opted to have my prop stripped, painted and dynamically balanced for a little less than $400.00.

The last thing to consider is insurance. You would have to get quotes to determine how close they are.
 
If you really want a high wing Cessna, a 177 is a much better choice than a 180 HP 172 and much more economical than a 182. The only reasons to buy a 182 over a Cardinal are 1) if you are regularly using short or high fields or 2) regularly taking heavy loads. 180 HP 172s are still slow - a well set up 160 HP Cherokee will run with most 180 HP 172s. If you don't want a CS prop, and speed is a thing (it seems to be), then get an Archer and cook the 172. Or get a Tiger and cook the 182.
 
...people around here love to exaggerate the added mx expenses of retractable landing gear, constant speed props, turbos, ETC. Ive owned a F33a bonanza for about 3 years now and the retractable landing gear and prop have not needed a penny of service...

I'm certain the next owner of the airplane will have to make up for that.

The implication that retractable landing gear and constant speed props are "cost free", or even cost equivalent to their fixed counterparts is ridiculous. They aren't.
 
My 1968 C172 with 180hp has always cost under 1000/yr annual with incidental maintenance(75hrs flying per year for last 10 years). During that time my 1958 Be 35J has never come out of annual for less than 2500, usually 3500(75hrs a year for last 10 years).Only routine engine maintenance on both, only routine landing gear maintenance on both, 2000 for CSP reseal and inspection for the bonanza I did not include. These figures are for the same owner(me), same mechanic, same amount of flying, and what I usually expect unless I get a big surprise. I enjoy taking long trips with the bonanza, love the reliability of the 172. If I get hit with an overhaul on engine and prop, it’s 40,000 for bonanza and 28,000 for Cessna(Firewall Forward in Colorado). Liability insurance is twice as much for Bonanza. Neither plane is for sale, love both, but when I do sale, it won’t be the 172.
 
Thanks all for your thoughts. I think I've read nearly every thread on "172 vs. 182" and it's always "buy whichever fits your mission best." My expected mission does include flying into high airports (I'm in SW Montana, after all) with people but not on every flight. Not even on every 4th flight. My girlfriend and I are just trying to be as realistic as possible when it comes to defining our mission. Yeah, the usability of the 182 would be great but hauling around all of that capability to be used so infrequently seems like a waste. I'm just trying to put a number on it all, even if it is an estimate.

I am probably spending more on my new to me CS prop right now (overhaul) than I spent on regular maintenance in my Archer over 3 years. That Archer was very economical.

Yikes! Surprise issue or was this expected after a pre-buy on the aircraft with the CS?

One last thing.. there are no hot rod 172’s...

Why do you say that?

I used "hot rod" as a catch-all phrase for the various 180, 195, and 210hp upgrades or stock configuration. The higher HP options aren't really on my list shopping/research list given they're also 6cyl with CS props but boy, the Stoots Aviation IO-370 in a 172 sure does seem like it'd do just what I need it to do! Doubt I'd be able to find one on the used market given the STC is still fairly new. But a boy can dream!

I think you will have well over twice the engine-prop expense with the 6 cylinder/csp combination compared to the 4 cyl fixed pitch.[...]The more cylinders an air cooled engine has, the more problems.

This is what I've been thinking. Routine mx seems like it'd be pretty much the same (except for what @idahoflier mentioned above (i.e., oil changes)) for both engines but the more that *can* go wrong should be taken into consideration.

When your taking off on a hot day from a high density altitude airport you won’t care that the 182 cost you a little more.

This is the primary reason why I'm considering a 182 at all. I live in SW Montana (KBZN) and in training this summer, have taken off from long, 8000' runways in a 160hp 172. I think the highest DA I saw this summer was close to 8,500'. In any ac I end up buying, some of my idealized mission is flying into and out of backcountry strips. It'd be nice to have those extra horses that a 182 provides, but at the same time, I should be able to mitigate needing them by 1. taking off early in the day and 2. not loading up to max weight, yeah? I've read here and elsewhere that good pilots (of which I am not one, yet) make it into--and out of!--high elevation strips all the time in 172/180 ac. Any heavier loaded missions, including those close to max weights, from long pavement to long pavement.

The last thing to consider is insurance. You would have to get quotes to determine how close they are.

As a relatively new pilot, I'm sure I'll be paying through the nose regardless of ac but you make some excellent points re: routine vs. overhaul maintenance.

If you really want a high wing Cessna, a 177 is a much better choice than a 180 HP 172 and much more economical than a 182. The only reasons to buy a 182 over a Cardinal are 1) if you are regularly using short or high fields or 2) regularly taking heavy loads. 180 HP 172s are still slow - a well set up 160 HP Cherokee will run with most 180 HP 172s. If you don't want a CS prop, and speed is a thing (it seems to be), then get an Archer and cook the 172. Or get a Tiger and cook the 182.

I've definitely not ruled out anything, including the Cardinal. I especially like the larger doors! But speed? Yeah, it'd be nice to get somewhere faster but part of the reason I enjoy flying is the journey. Being able to look down. Fast is great and upon the suggestion of another member here, I've put some expected flights into skyvector.com at different speeds to see how much of a difference in time it really makes. I've been using cruise speeds of 116kt for a 172/180 (from the Air Planes cruise performance chart here) and 135kt for a 182 and clearly, there's a difference in ETE but part of the fun is getting there, right?

My 1968 C172 with 180hp has always cost under 1000/yr annual with incidental maintenance(75hrs flying per year for last 10 years). During that time my 1958 Be 35J has never come out of annual for less than 2500, usually 3500(75hrs a year for last 10 years).Only routine engine maintenance on both, only routine landing gear maintenance on both, 2000 for CSP reseal and inspection for the bonanza I did not include. These figures are for the same owner(me), same mechanic, same amount of flying, and what I usually expect unless I get a big surprise. I enjoy taking long trips with the bonanza, love the reliability of the 172. If I get hit with an overhaul on engine and prop, it’s 40,000 for bonanza and 28,000 for Cessna(Firewall Forward in Colorado). Liability insurance is twice as much for Bonanza. Neither plane is for sale, love both, but when I do sale, it won’t be the 172.

This is great information. Thanks for sharing. As a statistician, I'm a big fan of controls. Seems like you've controlled well for my experimental needs. Bummer that neither is for sale, however!
 
A C177 may be a viable alternative for you. They have great visibility, are quite roomy and easy to get in an out of. My only experience was in a C177RG and from a performance perspective I wasn't overly impressed. The club I was in didn't allow retract operations at any unpaved strips so I can't comment on how suitable it is for BC flying.

Just out of curiosity I reviewed my logbook looking for round trip flights between KBOI and KMYL. That's about an 80NM flight and because of terrain I usually flew up at 8500 MSL and back at 9500 MSL. The round trip averaged 2.0 hrs on the Hobbs. That held true whether I was flying C172's, RK172's C182's, Archer's, the previous mentioned Cardinal and a Dakota. Sometimes the Dakota was a little bit faster. An Arrow consistently was about 0.9 on each leg. I'm mentioning that as just anecdotal evidence that on a typical $100 hamburger flight the C172 isn't getting it's wings blown off by the other aircraft mentioned...

One thought on surprises, while it's unlikely, you may be hit with a major repair expense like an overhaul when you least expect it...
 
If you are plan to fly in and out of backcountry strips I would check with a few 177 Cardinal owners. I don't think it has quite the same performance as a "hot rod" 172, but best to get some first hand feedback from folks who might use them that way first.

If it is just the two of you the 172 probably makes most sense. You'd want to make it as light as you can...perhaps take out the back seat entirely, for example.
 
I think I know the answer to this question but thought I'd ask the POA hive mind.

I'm at the early stages of aircraft ownership research and with (roughly) identified mission in hand, have started doing more research into C182s and 180hp C172s (and other hot-rod 172s). For me and my mission, a hot-rod 172 fits the bill really, really well.I've read here and on other forums that "the 182 is just as economical as a 172; you just have to dial the throttle back." That's all well and good and is totally fair, but what about the overall maintenance costs? I just don't know if I need to be carrying around all of the capabilities of a 182 for what would amount to likely 5-15% of my expected annual flights.

There's some brief discussion in this thread about the mx cost differential between the two and a user in a thread on backcountrypilots.org suggested that overhaul of a CS prop is just silly high. Is there anyway to get an estimate of how much mx costs on a 182 would be compared to a hot-rod 172 on an annual basis? For the purposes of this thought experiment, assume that both aircraft are in relatively good shape (for their age).

Is it a fair assumption to say that routine maintenance would 50% more for a 182 than a 4cyl 1872? 25% more? I don't expect exact numbers but would like to get an idea of proportionally, how much more in mx costs could you expect by owning a 182 vs. a 4cyl 172?
I know someone with a comparable plane to the C-182 (PA-28-235) with six-cylinder engine and CS prop. He babies his engine with frequent oil changes and close attention to his modern engine monitor and oil analysis, but still just had to drop $15K halfway to TBO to replace all six cylinders — oil consumption had suddenly jumped to 1 quart/hour (or a bit more), and his shop wasn't able to trace any cause after weeks of investigation (no clues from engine monitor data or oil analysis, either).

That kind of problem can happen to anyone, but
with a simple 0-360 or IO-360 4-cylinder engine on e.g. a 180hp C172 or a PA-28-180/-181, it would at least have cost him only 2/3 as much for that top overhaul (oil consumption has been fine since — they never found a cause). And with the simpler engine, the problem might not even have popped up in the first place — who knows?

If you really don't need that extra speed and power for 90+% of your flying, keep it simple and affordable. My 160 hp PA-28-161 "starter" plane is still doing everything I need 18 years later — I thought I'd upgrade a few years after I bought it, but I never needed to. And with such a simple plane, I've gone over 10 years now without any big maintenance sticker shocks.
 
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