which is cheaper,IC or ELECTRIC?

[The Wright Stuff]

For the sake of attempting to answer the question, as opposed to simply saying "it depends" or posing a new question, I'm going to stick my neck out and say that in general, electric is cheaper.

Look at it this way. In the mathematical limit of a huge number of flights, i.e. many hundred, we may disregard the initial start up costs of purchasing hardware as negligible. So the cost per flight may be approximated by simply comparing the cost of a tank of fuel, versus the cost of charging a battery. Of course, the batteries will need to be replaced every 500 flights or so, but spread out, again on a 'per flight' basis, the cost is going to be small.

This comparison is only going to get bigger as time goes by, since economy of scale means fuel prices go up, and battery prices come down.

Of course, you may argue that the initial costs are important too, and cannot be disregarded in this manner until the "break-even" point is reached.

My response would be: "go fly more, get past the break even point, then you don't need to worry about it!"

[Jon H]

Posted by SONNY MONKS on 28/11/2018 12:20:50:

Thanks peter,Do motors burn out quicker,or the ESCs,or are they as durable as an engine,i just dont have the experience to witness this?

depends on the engine and the electronics. Some ESC's smell like fire before you even take them out of the packet but some are fine. Equally some engines are better made than others and will last longer.

As with most things it boils down to user error. In the case of engines, poor fuel, wrong plug, wrong prop, overheating, dirt ingestion etc will kill them long before wear. Equally, with electric wrong prop, poor cooling, wrong volts, wrong amps, flirting constantly with the max continuous rating etc can all kill motors and speedo's prematurely.

Buster, you did strike a nerve but not the one you think. It was the misinformation nerve not the 'yay engines' nerve. To fly what i fly on electric i can guarantee you will need more heavy gear with you

And as Nigel very rightly points out, it should be fuel,fly, forget. If not there is some maintenance required.

[Jon H]

Posted by The Wright Stuff on 28/11/2018 12:43:59:

Of course, the batteries will need to be replaced every 500 flights or so

no way Alan! i dont think i have ever managed to get a lipo past 30 or 40 cycles before i deemed it dead. it really annoyed me as they were balanced, stored at the right volts, never over discharged and my little 400 heli barely tickled them on current draw. It was all very disappointing

[Chris Walby]

As someone else brought this up...noise...those screaming EFD's and electric pushers, all with no noise test!

Not an issue for me, but some of the older guys find electric with its mass of permutations for ESC's, motors, batteries with cell count /C ratings very confusing..

IC, slow run needle... adjust once in a blue moon and main needle once per day....even I can get that right

To make IC as complicated as electric perhaps we should be offered different carb sizes, cam profiles, flywheel weights and exhausts lengths...and the petrol guys map-able electronic ignition timing....

[The Wright Stuff]

All very possibly true, but this thread is about cost. There are already hundreds of existing threads debating the relative merits, surely?

Edited By The Wright Stuff on 28/11/2018 13:07:17

[Dave Hess]

The reliability of the electrical components is pretty good as long as you use them within their design parameters. The only electrical failure I've had was an ESC that made the motor scream. Replacement cost was about £12 - not excactly going to make me bankrupt. I can't remember ever having a failure with an IC engine, though there were many occasions when they were too temperamental to risk flying, and I lost more models due to IC engine cut-out than any other reason. Also, I had a few engine mounts crack.

From a flying relability point of view, electric must win hands down.

And don't forget to factor in the cost of glow plugs. Looking in my old flight box, I can see loads of empty buble packs. I must have spent more on glow plugs than I have on batteries.

Edited By Dave Hess on 28/11/2018 14:07:30

[Don Fry]

Posted by The Wright Stuff on 28/11/2018 13:06:48:

All very possibly true, but this thread is about cost. There are already hundreds of existing threads debating the relative merits, surely?

Edited By The Wright Stuff on 28/11/2018 13:07:17

You are absolutely right, but having read the logic statement you made at 12.43 pm, I bet you have a Rolls Royce purchased as a long mileage economy device, and justify the long detour on the daily commute as an extra saving.🛩🤗

[Trevor Crook]

For normal club-sized models (.40 to .60 size) there isn't much difference in cost. Best to consider all the other pros and cons. I flew ic for the first 30-odd years of my modelling life, leccy only for the last 10. I certainly find ep far less of a faff than i.c. and, despite what others have said, much more reliable.

There is much more to wear out in an i.c. motor than an electric one, which only has the bearings as a friction surface. If solid-state electronics is properly designed, and used within its design parameters, the esc should have an extremely long life.

As for the "simplicity" of i.c. Brian Winch finds plenty to write about every month! I still read his excellent column, he is a wealth of engineering knowledge. I'm just thankful I'm no longer subject to falling off silencers, dodgy fuel or plugs, rotting tank plumbing and the various other ailments he describes fixes for.

If you plan on going flying for a day, Jon is right that there is probably less gear to take for i.c. I only tend to go to the field for a couple of hours, so take 10 or so charged batteries and 2 or 3 models to fly with them, so no field charging. This of course requires more preparation on the charging front than a couple of i.c. models would need.

The debate continues!

[The Wright Stuff]

On the cusp of being on the topic of cost, agree with Trevor in the sense that I concede that I would not make a decision between I.C. and electric on the basis of cost alone.

Don, you are cynical but not unreasonable. Of course, it depends upon the definition of cost. Cost per minute of flight? Cost per flight? Cost per year? Upfront cost?

One perfectly valid economics approach is to consider the marginal cost of the (n+1)th flight, given the nth has been completed. the only way to answer the question is to constrain it.

Right, I'm done here!

[Nigel R]

Debate only continues because we strayed off topic, cost wise, nothing in it, case closed at post #2.

"and I lost more models due to IC engine cut-out than any other reason. Also, I had a few engine mounts crack.

From a flying relability point of view, electric must win hands down"

Well, I've never had an engine mount crack. I don't recall ever losing a model due to deadstick. In fact, I don't recall ever having many deadsticks. Lost a few models to bad flying or building, but live and learn. I don't remember changing plugs because they expired very much. I've never had a silencer fall off, or a carb come loose, or a tank crack, or plumbing rot, or copper tubes fall apart. I've never failed a noise test.

I've flown without setting up properly a few times, had dodgy throttling or had the engine quit. But that's my fault.

I had the plumbing come off a tank once. Took a very long time to fill the fuselage up. Also my fault.

I've seen the odd bearing wear out.

I did break a motor utterly beyond repair once, but that was because I spun the plane into the tarmac as a learner.

Glow seems perfectly ok to me. Maybe I've lead a charmed life with glow motors.

I've had a few deadsticks with electric. Wonky (manufacturer) solder joints failed. A cooked ESC. Motor shaft coming loose. But that's three or four times in hundreds of flights.

Reliability? About the same in my book.

I'm a sample size of one, take with pinch of salt.

[Don Fry]

The Wright Stuff, you have made my day. Thank you mate. To be described a a cynic, by a man so obviously intelligent, is praise indeed.

[Peter Christy]

Most of my "serious" models are IC, and my "fun" models electric - with two exceptions - both scale helicopters which are electric.

As far as reliability goes, all I can say is that my vintage aerobatic model is being hauled around in grand style by an engine that I bought in 1968!!! It still runs perfectly today, and has only stopped on me in flight once, when I hadn't tightened the plug enough, and it blew out!

On the other hand, the biggest issue I have suffered with LiPos is that they never seem to last anywhere near as long as claimed. In the relatively short time I've been flying electric, I must have replaced half my LiPos because of "puffing", despite never pushing them to their limits, over discharging or anything else. There seems to be little difference in this respect between expensive ones and cheap ones, though I do avoid *really* cheap ones. Very disappointing - and expensive!

--

Pete

[The Wright Stuff]

Posted by Don Fry on 28/11/2018 15:22:54:

The Wright Stuff, you have made my day. Thank you mate. To be described a a cynic, by a man so obviously intelligent, is praise indeed.

No problem Don, pleased to be of service!

[Bob Cotsford]

Posted by Nigel R on 28/11/2018 14:55:36:

Debate only continues because we strayed off topic, cost wise, nothing in it, case closed at post #2.

"and I lost more models due to IC engine cut-out than any other reason. Also, I had a few engine mounts crack.

From a flying relability point of view, electric must win hands down"

Well, I've never had an engine mount crack. I don't recall ever losing a model due to deadstick. In fact, I don't recall ever having many deadsticks. Lost a few models to bad flying or building, but live and learn. I don't remember changing plugs because they expired very much. I've never had a silencer fall off, or a carb come loose, or a tank crack, or plumbing rot, or copper tubes fall apart. I've never failed a noise test.

I've flown without setting up properly a few times, had dodgy throttling or had the engine quit. But that's my fault.

I had the plumbing come off a tank once. Took a very long time to fill the fuselage up. Also my fault.

I've seen the odd bearing wear out.

I did break a motor utterly beyond repair once, but that was because I spun the plane into the tarmac as a learner.

Glow seems perfectly ok to me. Maybe I've lead a charmed life with glow motors.

I've had a few deadsticks with electric. Wonky (manufacturer) solder joints failed. A cooked ESC. Motor shaft coming loose. But that's three or four times in hundreds of flights.

Reliability? About the same in my book.

I'm a sample size of one, take with pinch of salt.

No, that sounds about par for the course. You have a problem, you learn, you move on. It doesn't matter whether it's ic or electric.

One thing that I have found very definitely in favour of electric - it's easier to pass our 80dBa noise test.

Maybe it's just me but I find it hard to understand why so many deadsticks result in crashes, there are just two golden rules that should be drummed in from day one (apart from don't fly over the pits). Don't fly too far downwind and don't fly too low.

[Geoff S]

Electric flight components have a very long life provided you keep within their parameters. That is mostly the specified current ratings or preferably no more than 80% of them.

The only thing to wear on a brushless motor is a couple of bearings that are very cheap and easy to replace. I did have a supposedly quality motor (an Axi) throw its magnets a good few years ago and I replaced the poor quality motor supplied with my Phoenix 2K motor glider (total cost of glider inc motor, esc and servos was about £75 IIRC) but that's about it for motors.

ESCs are also very reliable of you keep the current well below the stated maximum. I had one failure, again a long time ago, when one MOSFET failed (I assume). I replaced it at very low cost. Modern brushless ESCs are fantastic pieces of electronic design and do a lot for very little money.

Treated well and simple measurements made to make sure you're not over-stressing them they are very reliable.

Liquid fuelled engines also seem to last a long time. When you think how few hours model petrol engines actually run compared to those used on commercial chainsaws etc then their lifetime is very long indeed. They don't go wrong very often mechanically except I've had to replace bearing because of corrosion several times. They're also generally more expensive to replace/repair after a crash than equivalent small brushless motors.

I doubt if there's much to choose on a life-span basis.

I've been playing with electricity and electronics just about all of my life from childhood to one-foot-in-the-grave senility so the brushless/LiPo revolution is right up my street, so that's what I like. I've also played with engines a lot in my motor cycling days and quite enjoy tinkering with them but for flying it's 90% electric for me.

Geoff

[Dave Hess]

I've just been next door to ask my neighbour whether he's had any reliability issues with IC engines. He confirmed that in the last 20 years he's never had to do a dead stick landing, and he's never had one conk out either. In fact he's not even had one cough and splutter, so these things must be just a myth and I must be dreaming each time I see it at my local club. Maybe I need more sleep. Does it matter that he's never touched an RC plane in the last 20 years either?

[john stones 1 - Moderator]

Posted by Dave Hess on 28/11/2018 18:20:36:

I've just been next door to ask my neighbour whether he's had any reliability issues with IC engines. He confirmed that in the last 20 years he's never had to do a dead stick landing, and he's never had one conk out either. In fact he's not even had one cough and splutter, so these things must be just a myth and I must be dreaming each time I see it at my local club. Maybe I need more sleep. Does it matter that he's never touched an RC plane in the last 20 years either?

Which did he say was cheapest ?

[Don Fry]

Posted by Dave Hess on 28/11/2018 18:20:36:

I've just been next door to ask my neighbour whether he's had any reliability issues with IC engines. He confirmed that in the last 20 years he's never had to do a dead stick landing, and he's never had one conk out either. In fact he's not even had one cough and splutter, so these things must be just a myth and I must be dreaming each time I see it at my local club. Maybe I need more sleep. Does it matter that he's never touched an RC plane in the last 20 years either?

So why ask him, brother.

[Don Fry]

Mr Hess seems silent John, or perhaps writing a crushing response.

[ASH.]

Hey Buster,

I too, like many others find electric flight boring and soulless.. and it's not about just about power and performance.

IC engines are living breathing things. There's a lot going on in an engine,, mechanical and chemical, and it all has to come together perfectly to work properly - just like in your car. Except, it's done on such a miniature scale. I find that fascinating. When the plane is in the air you're not consciously thinking all this but you know it's happening from the sight smell and sound.

I'm glad I've had such good success and satisfaction with all my engines. This satisfaction I put this down to time and effort spent in learning about them to maximize their full potential. They are not difficult to operate they just require some patience.. At the end of the day it's about how it makes you 'feel' - that's why we fly.

As for MDS (Made for Dead Stick), please don't be too disparaging about the Russian make.. My first glow was an MDS48, ran faultlessly and saw me through my 'A' cert and beyond to the disbelief of club mates.

Lastly, if you've never flown IC or had much luck with them and are strictly electric - then that's okay. You don't know what you are missing.

Edited By ASH. on 28/11/2018 20:06:29

[PatMc]

Engines don't have souls (does anything ?), they are lumps of various metals hacked into shape, assembled and made to function by the application of the correct mixture of fuel & air.
There sole useful function is to provide power, which is exactly the same function of an electric motor.

[eflightray]

Cost wise, and if you are interested in building your own models, I found Depron so much cheaper than balsa, plus with electric you don't need to worry about fuel proofing.

I also like multi-motor models, so for me electric power just seems easier.

With 30 years of IC power and the last 30 years with electric power, both had their good and not so good points.

But shouldn't you be asking your wife/girlfriend ?, (or even both   )

 

.

Edited By eflightray on 28/11/2018 20:11:35

[ASH.]

Ooooh... I don't think Jon would agree, nor I on - "they are lumps of various metals hacked into shape". Far from it.

[Andrew767]

Posted by PatMc on 28/11/2018 20:03:48:

Engines don't have souls (does anything ?), they are lumps of various metals hacked into shape, assembled and made to function by the application of the correct mixture of fuel & air.
There sole useful function is to provide power, which is exactly the same function of an electric motor.

Would be nice if someone could explain what this soul is,other than merely something that they like.

Andrew

[eflightray]

IC fliers often still need the help of electric power, ...... to start their engines for them.

I was always a 'flicker', back in the day.

.