HONDA vtec engine

[dkatwa]

I have heard several times that there has never been a failure of a Honda VTEC engine, despite building 20 million of them or so.

Do you think someone would be brave to put one of those engines in the SEP?

Gotta be worth a try, surely?

Just a thought..

[ShyTorque]

Trouble is, when the VTEC kicks in, the rpm increases so rapidly, the prop will probably overspeed!

(Youngest son has a Type R Civic, it goes like stink).

[stickandrudderman]

Indeed, the Honda is a fantastic engine........in cars.
It's main asset is its' apparent schizophrenia, one minute a docile town car, the next it's screaming for the horizon leaving your eyeballs pinned to the back of your skull. Not the lind of predictable performance one wants when trying to pick up a couple of kts on late final!
(Apart from the fact that all propellor driven aircraft have dynamic limitations imposed on them by the fact that they have a propellor attached to them which doesn't like too many RPMs)

[Morrisman1]

I think they are referring to the VTEC system, not the whole engine. It would be damn near impossible not to have an engine fail out of all those. Id question that claim too because at least 50% of engine problems the manufacturer/dealership will never hear about.

I dont know other peoples opinions but I don't like the idea of a piston engine in-front of me screaming at 8000rpm driving through a reduction gearbox.

[pistongone]

Just a thought? Why are reduction gearboxes viewed with a little scepticism in the aviation environment, whereas automotive applications rarely experience failures? I would have thought most high mileage vehicle operators have recon lumps fitted long before the gear box goes U/S? Although the argument for auto engines not producing 75% power for long periods and not really being suited to these applications seems to be a valid stand point.
The problem with "car engines" in aviation is in the design. Short stroke car engines designed to deliver short bursts of high power low torque performance is diametrically opposed long stroke high torque (relatively per cc) low power aviation engines.
I would guess that gas turbines will feature in t5he future, just got to get those costs down!
PG.

[ShyTorque]

Gas turbines use reduction gearboxes too, though.... ;)

[Morrisman1]

It's not the reduction gearbox which worries me, its the small capacity automotive engine spinning at 5000-6000 rpm all day which worries me. Id take a big banger any day. Call me old fashioned but keeping things simple in my eyes is better in aviation. Its just a shame that fuel injection and electronic ignition has taken so long to get to certified engines. That lycoming ie2 thing looks interesting

[Deeday]

Gas turbines use reduction gearboxes too, though....Yes, but gas turbines don't go about hammering a transmission shaft tens of times a second.
You could say that gas turbines are from Venus, pistons from Mars ;)

[IO540]

whereas automotive applications rarely experience failures?

I had an XR3i in the 1980s, and the gearbox shredded itself, gradually over about 30 miles, through the disintegration of a bearing around the tacho takeoff shaft, which took off the teeth one by one... by the time I got home, only the 4th gear was working.

Then I had a total loss of coolant in a Toyota Celica (suprisingly).

And two alternators go in another (imported) Toyota, to date.

Countless cracked aircon compressors in the Celica too - an experience reported by aircraft aircon system owners too.

I have flown about 1000 airborne hours, which is perhaps 1/2 of my total car / motorbike mileage, yet I have not had a single mechanical failure on the aircraft, whose engine sits there at 65% power all the time, and best part of 100% power for some minutes after each takeoff.

On the basis of the above admittedly small set of data points, I don't think I would swap my IO540 for any car engine.

[flyinkiwi]

I had an Integra with a B16A - engine was bullet proof, can't say the same for the clutch, gearbox, CV boots, air conditioning compressor, most of the electrics... :rolleyes:

[POBJOY]

Seven cylinders about 115 lbs, 90 hp 3200 rpm and a reduction box that was built by Swiss Gnomes living in Hooton Park.
Swings a 7ft plus prop and gives plenty of THRUST.
Add an electronic ignition and away you go.

[Jan Olieslagers]

There's nothing wrong with reduction gear on piston engines indeed. The Pobjoy is just one example, and of course closest to what we need in small planes. But higher up the power scale, reduction was almost universal, from the RR Merlin to the Wright R3350, and even the slower Jumo diesels had them.

[Dan Winterland]

The VTEC engine has sucessfully been adapted for marine use. I sometimes drive a speedboat with a Honda outboard derived from the car engine. It's the best outboard I've ever used.

[pistongone]

The reduction box is not really the problem. The OP was looking at putting a car engine in a plane, and to that end they are not really compatible. There will be exceptions, to prove the rule in most walks of life. I was at St Omer just before Christmas and a chap there has a Peugeot Diesel in a small Plane, I think it was a Jodel but not sure. But as a generalisation car engines are designed for a very different role.
Modern car engines use a lot of RPM to achieve the power output for the sales brochures, but most will only be turning at 3-4000 rpm at normal cruise speeds(70-90mph, don't you love those German autobahns?) Having just written that, it is interesting that the car and aircraft engine are designed to operate the majority of the time in roughly the same RPM range? I would have thought it has something to do with internal friction losses and heat build up?
Any how off on my bike to work now, which funnily enough is a Honda CBF600 with fuel injection and miles of wiring to all sorts of gadgets:ok: Most of which are designed to meet stringent emission regs and have sod all to do with power or longevity.
Nice memories IO540 of the Escort, the Mk3 was a legend in its day, not forgetting the RS Turbo, never really whent much faster though with the turbo bolted on :E Justn looked better in the rally colours.
Safe flying PG

[englishal]

Did you have an "XR3i girl" to go with the Car IO540 :D

Seriously though, engines these days have come on leaps and bounds over the old 1980's ones. I had the Sierra XR4i (without the girl) and it was brilliant...However, it did eventually die, just before going into the Dartford Tunnel with serious amounts of smoke and flames under the bonnet as the engine seized up! But saying that, it was almost 20 years old at the time and the only thing that I did differently was change the oil a few weeks before. Had I left the oil alone it would probably have been ok!

I think that there are numerous "partial" engine failure in aeroplanes, cracked cylinder heads etc., and you get far less of them in a modern, liquid cooled, car engine. The taxi driver I use to get to LHR drives his diesel Citroens up to 350,000 miles before changing the car and even with those miles on the clock, the thing still sounds as good as new and he rarely has any engine problems. At an average speed of 50 mph (which is quite high average) that equates to 7000 hours.

[1800ed]

That 'Honda engines never fail' thing comes from Top Gear. A very reputable source indeed.

[aerobatic_dude]

The B series engine is one of the best automotive engines ever made IMO.

As someone who is a keen track day enthusiast ( mainly drag racing) i've had several B series honda engines. My current is a B16A2 with lots of head work and a good re-mapped ECU. It makes power to about 88 -8900rpm ;) Never had any real problems with gearbox, drives, etc. I broke 1 driveshaft while drag racing on the local drag strip and that was the height of my problems.

How the engine would serve in an aviation application I don't know. Such a high revving engine may not be ideal for an aviation application.

[ShyTorque]

I have flown about 1000 airborne hours, which is perhaps 1/2 of my total car / motorbike mileage, yet I have not had a single mechanical failure on the aircraft, whose engine sits there at 65% power all the time, and best part of 100% power for some minutes after each takeoff.

On the basis of the above admittedly small set of data points, I don't think I would swap my IO540 for any car engine.

I've got about 1,000 hours on single piston engined light aircraft and about 8,000 hours on small turbines, both singles and twins for the latter. I also have 40 years of riding experience on motorbikes, new and old, two and four stroke and the same amount of experience in cars, including some amateur motorsport.

I think it best to keep the big capacity, torquey engines in the sky and the more revvy engines on the ground. I wouldn't willingly swap back from my turbines for the airborne stuff though, even though I've had neither type fail on me in the air. Having said that, there is no twin piston engined aircraft that can do my required type of flying work, so there is no choice anyway. :)

The B series engine is one of the best automotive engines ever made IMO.

I take it you mean the Honda? "B series" means something else to us of a certain vintage. AKA Leyland. That was still a good engine in it's day, though. :ok:

[BEagle]

I had a Prelude 2.2i VTEC - the engine was absolutely superb. Very reliable and when you hit the VTEC zone, it was like lighting the afterburner. Then take it to the red line, shift up and the ratios were so cleverly chosen that you'd be at the start of the VTEC zone for the next gear....:ok:

But not really an aeroplane engine.

[dkatwa]

so thats a no no for the Vtech....thanks for the comments....:ok:

[B2N2]

drives his diesel Citroens up to 350,000 miles before changing the car and even with those miles on the clock, the thing still sounds as good as new and he rarely has any engine problems. At an average speed of 50 mph (which is quite high average) that equates to 7000 hours

Things is a car only requires what 30-40(?)HP to run a 50 MPH which is about 20% of their maximum.
Airplane engines run at leats at 65% of their maximum.
That Citroen engine would be amazing if it would run 3500hrs at an average of 100MPH, but it won't.

With a small airplane a gearbox adds weight. weight is bad as it reduces usefull load, performance etc etc etc.
Light aircraft usually do not have an abundance of excess performance to begin with. So you are generally stuck with an engine that runs in the same RPM range as the propeller which is 2500-3000-ish.
Although there are some succesfull "gearbox" engines around:
DA40/42 w/ Thielert or Austro
Cessna 421, some models had geared engines.

Problem is aviation gearboxes do not have variable ratio.
Lets take a little example with the VTEC engine assuming we have a 2:1 gear box ratio;
VTEC 4000 RPM , propeller 2000 RPM :ok:
VTEC 8000 RPM , propeller 4000 RPM :eek:

And this is what happens when the propeller overspeeds
YouTube - Relentless mayday 9_14_2010_slow motion.mp4 (http://www.youtube.com/watch?v=lkRbsHWa6Hk&feature=player_embedded)


Source: EAA News - Reno 2010: Relentless Loses Prop in Flight (http://www.eaa.org/news/2010/2010-09-15_relentless.asp)

[Jan Olieslagers]

Can't see why it should be a "no-no". Even if it is not ideal, what engine is? If the ideal engine existed, all others would disappear from the market. Aviation is all about compromises, and this engine might well be an acceptable compromise for some people in some planes in some applications.

I do think it is worth a try - if you've got a lot of time and a fair stock of mechanical ability and a well-equipped workshop available.

[BabyBear]

I have flown about 1000 airborne hours, which is perhaps 1/2 of my total car / motorbike mileage, yet I have not had a single mechanical failure on the aircraft, whose engine sits there at 65% power all the time, and best part of 100% power for some minutes after each takeoff.

:confused:

IO540 has your arithmetic deserted you or has mine? On the other hand it may be my lack of will power when her indoors is not present to govern the single malt intake, I know it's ealry, but when the cat's away!

[Mechta]

There are two different threads going on here. One is about engines with a wide RPM range, and the other is gearboxes.

The advantage of a high revving engine is that it gets its power from its speed and not its capacity, so it can be smaller. If it has variable valve timing, of which V-TEC is one manufacturer's term for it; it can also idle comfortably without the wild valve overlaps that a 'stage 3' racing camshaft would have to get power at high RPM. To make this high RPM usable on an aeroplane propeller, which should work on the biggest volume of air as possible and keep the blade tip speed subsonic, a gearbox and, ideally, a variable pitch propeller, are required.

Now onto gearboxes. A gearbox works fine when it has a smooth constant torque coming into it and its not being asked to accelerate or decelerate. On a gas turbine, the torque is a continuous load so there isn't a problem.


On a car, between the engine and gearbox is a flywheel and a clutch or torque converter. On a direct drive aeroplane engine, the propeller IS the flywheel. The problems start when the engine and its flywheel are separated by a gearbox.

When the piston travels up the cylinder compressing the fuel mixture, this takes energy, so the engine slows down. When the mixture ignites, the engine accelerates. This results in torque reversal, which is why at a slow idle the engine rocks backwards and forwards, especially if it is on anti-vibration mounts, as the flywheel effect causes the crankshaft to try and go at constant speed, and the engine tries to rock in the opposite direction to accomodate the acceleration and deceleration.

If a gearbox is now added to the drivetrain it will try and accelerate and decellerate the propeller. The propeller being a good flywheel, takes no notice, so the changes in speed try and change the direction of the bit in between, AKA the gears. On a car if it is at a slow idle, the likelihood is the clutch is depressed, and the gearbox is disconnected from the engine.

In the aeroplane, if there is no clutch, the torque reversal is hammering away at the gears. This is worse at low RPMs as there is a longer duration and hence greater amplitude of movement (the hammer hits from further away). Some microlight engines use a centrifugal clutch, so the gearbox is only driven when the engine is above the damaging torque reversal RPM. The alternative as per Thielert is to put a torque limiter in, which is a clutch with a preset load on it. If the torque reversal gets too much, the clutch slips.

[Mechta]

Things is a car only requires what 30-40(?)HP to run a 50 MPH which is about 20% of their maximum.
Airplane engines run at leats at 65% of their maximum.
That Citroen engine would be amazing if it would run 3500hrs at an average of 100MPH, but it won't.If this the aircraft referred to DIYer Builds Peugeot AX 106 Diesel Engine Powered Wooden Aircraft - Auto Motto (http://www.automotto.org/entry/diyer-builds-peugeot-ax-106-engine-powered-wooden-aircraft/) with the 1.4 or 1.5 litre Citroen TUD engine used in the Citroen AX, Saxo and Peugeot 106, it is worth bearing in mind that the French have or had a speed limit of 140km/h (87mph) on their autoroutes. The engine will have been designed to cruise all day at that speed, and the total horsepower of the engine is only 58bhp (53bhp for the 1.4). This engine is designed to operate at far closer to an aircraft engine regime than a larger more powerful one would.

I owned a Citroen AX 1.4 diesel, and my memory of the weekly 100 mile journey to Filton, along the M4, was having my foot hard to the floor for most of the way. The car already had 150,000 miles on it when I bought it but never gave any trouble.

You may not get 3500 hours from the Citroen engine, but you could probably throw the engine away, buy another and still have change from the price of a Lycoming.

Here's the original article in French: Gaz'aile 2 (http://gazaile2.free.fr/)

[Jan Olieslagers]

Mechta, many thanks for explaining about the need for damping - I had heard of it but never managed to understand. Have you any idea how this problem was tackled in the big engines like the RR Merlin? Very intensive maintenance ( if they ever made it to the specified time ) I should think?

As for the Citroen diesel: it still uses a reduction, as can be seen in one photograph in the article you mentioned. I suppose the belt(s?) take up the vibration in that installation? I remember seeing such a bird at Saint Yann last summer, that gold-anodised aluminium is not easy to forget. Was surprised to learn from the builder that the engine block as such had scarcely been modified.

And just to get the detail right: the French motorway speed limit is 130 km/h - my own country even has 120 km/h - but they are not very strict about it. As I've said before, the further South one goes, the greater the distance between legal and real.

[IO540]

I take that to mean perhaps 150,000 miles flying the aircraft, and 300,000 total miles in cars/motorcycles. He doesn't drive much!

Indeed; I attach a lot of value to living in a nice place, and living very close to my place of work (30 mins' walk). It's a major plank of "quality of life".

Actually I have probably driven 400k miles since 1977; 100k of that on 2 wheels.

[POBJOY]

When Pobjoy made his engine he relised that he would need revs to get the power but a slow prop speed for thrust and effiency.
Hence the reduction drive.However this drive also incorporated an "anti-chatter" device to help prevent the "chatter" that occured at low revs when the engine was warming up (less than 1100rpm).When power was increased to 1200 and over the engine suddenly will "go quiet" as the railway sleeper of a prop starts to help with the flywheel effect and the natural balance of the engine comes into effect.
There is no question with regard to the effect of a large dia prop on the smooth running of an engine plus the added efficient thrust it provides.
Of course being Pobjoy he also included an "oil slinger" centifugal strainer into the sysytem to help with the filtration.
With a double helical gear driving all this it was about as good as it gets from an engineering aspect, but no doubt expensive to produce.
What reduction gears DO NOT LIKE is the sort of rapid close rapid open operations that engines in training machines get, but then that can be incorporated in the "engine handling" training if required.
Being a radial cooling was never a problem unlike the "close cowled" flat 6 & 8 configuration of Mr Continental and Lycoming.
For years i flew Cessna 175 Skylark (GO 300e i think it was).This went like stink climbed like a homesick angel and was very smooth.However they had a poor reputation mainly due to being used as parachute planes and getting overheated.
If used for what they were designed for and the speed kept up on climbs they were fine.The rated power was at 2800 (with a large vp prop) so the TBO was only 1200 as opposed to 1500hrs but if operated by "thinking pilots" were a great machine out of a strip with a full load.

[Mechta]

Jan, The Merlin being a V12 had a power stroke every 1/6 of a revolution, whereas a four cylinder engine rotates 1/2 a revolution between power strokes, so there was a lot less opportunity for torque reversal with twelve cylinders. I'm not aware of any torque limiter or torsional damper on the Merlin to protect the gearbox, although I'm sure there will be a Ppruner who will know. I suspect the reduction in vibration was one of the reasons for going for so many cylinders, as well as to reduce the cross-sectional area.

The Merlin was also designed with a gearbox from the start, so the loads would have been taken into consideration in all parts at the design stage.

Thanks for the correction about the French autoroute speed limit. I knew it was high than UK motorway speed, but couldn't remember by how much.

As an aside, I've just found this description of the Dieselis, which if the figures are to believed would make anyone paying Lycoming running costs cry. DslGB001 (http://membres.multimania.fr/dieselis/gb2.htm)

[englishal]

The diesel aviation engines have a gearbox, and on the DA42 (the only diesel I have flown) they have a light composite prop and the engines are mounted on movable mounts. If you grab the spinner on the ground, you can wiggle the prop left and right and up and down. It is a bit disconcerting the first time you go into turbulence as the prop "wobbles" but it is very smooth in the aeroplane.

The engines themselves are variations on automotive engines, as the dipstick in the DA42 is the same as the one in my Audi ;) Engine mangement can be handled by FADEC which does a much better job of it than a human (as long as it doesn't stop doing that job!). Perhaps if someone came out with a relatively high power petrol engine/FADEC combination, it would be lighter and more economical than a Lycoming and less prone to damage from things like shock cooling / mishandling?

Actually that describes the Honda/TCM project exactly, I wonder if they are continuing with the project?

[Morrisman1]

Perhaps if someone came out with a relatively high power petrol engine/FADEC combination, it would be lighter and more economical than a Lycoming and less prone to damage from things like shock cooling / mishandling?


The Lycoming ie2 is just that, reasonably high power (350hp) fully up to date with the technology. Its being introduced this year from what the news sites are saying