Arthur K

My question is how many of you guys out there have damaged or lost your planes to dead sticks when there was absolutely no reason for your engine to quit on you
This weekend we damaged 2 40% + Airplanes both had Da 150s both were performing flawless all season on Saturday mine quit at Idol in an inverted flat spin
the second Bob's on Sunday in a hover at Half throttle both airplanes will be fine with some minor repair however 2 $100.00 + props are toast the finish on the planes are damaged and a few days of flying are lost
Now we pay a nice chunk of change to go out there and get what is supposedly one of the finest aircraft engines in the market, they cost almost as much as a four cylinder car engine and yet we have to depend on these cheep ass sensitive chainsaw carburetors to pump the fuel out of our gas tanks mix it with air and get it to the combustion chamber
ALL I AM SAYING IS WHY they can’t come up with a nice reliable system instead of using these chainsaw carbs maybe a nice electronic fuel injection system
I am no expert at this but hey for $1500 I can get a outboard motor for my boat with fuel injection oil injection heck a few more dollars and I get power trim
and some of these engines are no bigger then a DA 150 maybe they should borough some parts and technology from that Industry it seems like we have been stuck on chainsaws for the last 10 years for crying out loud some Glow engines are more sophisticated then these so called top of the line power plants we trust with $7000.00 AIRCRAFT
now there answer is going to be we do not have the market to R&D so before I get that answer I say bull Just in my club alone I could name 50 guy's that Have large Gassers
and 75% of that Is DA because Myself and a few of the more experienced modelers steered them that way I bet there are thousands tens of thousands units out in just north America and it's still growing most modelers in our sport will eventually go gas so give us a product we can Depend on.

rmh

There is always a reason -unless you still believe in the tooth fairy.
EFI?
I hope not
Walbro type carb is a beautiful simple setup -perhaps a higher precision version with better filter setup (external for service and better seals on throttle blade).
OS puts out an "FI" setup on their OS140 etc., no thanks.
What will you really pay for a good carb ?
$75.00
$150.00
Try to get a good workable FI for double that .
If I were to ak for the perfect model gasoline fuel induction-it would be this:
external inlet filter
priming bulb
exhaust pressure regulated pumping .
sealed throttle blade shaft.
None of this is really expensive .
The new MVVS twin has a throttle blade to idle needle coupling feature -which is reported to work very well - IF just if - they could add an adjustable accelerator pump and a "power valve" then I would be happy but the cost just for these two features would likely be higher than the market would bear.

aviti

My Feedback: (54)

I agree. Some guys will point to the user which is often the case but many other times the story is just like this where it just happens. I think for the amount we have invested in these large aircraft, many of us would be willing to pay more money for an engine that has a more reliable fuel/air delivery system.

Albatross

My Feedback: (7)

Hi
Ever since I start flying airplanes (glow), the dead sticks were something that I had to deal.
When I switched to gassers hoping to see my self in the safe side as far as engine flame outs.

Unfortunately buying a gas engine does not mean a that you get an insurance against flame outs.

IMO there are a tons of factors that can lead the engine flame out, carburetor, clogged filters, overheating you name them. What you mention about of a kind fuel injection device sounds interesting. However it might add cost and weight and complexity. In addition as far as I know the carburetors that we use in our gas engines pump fuel from the tank; which somehow insures the gas/air mixture gets the IC chamber.

BTW I was working with my garden tools this weekend, I wondered why this weed eater engine has not flame out on me during all these years!
I have not even replaced the spark plug ever since I bought it more than 4 years ago!
Of course the weed-eater neither the snow blower get airborne. This comparsion may lead to false conclusions.

I am not an expert in this regarding, therefore the best advice I can think off is that you may want to address this question to the Gas Engine forum.

Most likely You Will find more expertise in this regarding.

Arthur K

Not realy many times there is no reason and Like I said we are using simple chain saw technology I am not new to this at the Toronto flying club we are prevlaged to have Ron Chapman as one of our active members Now for some of you that do not Know him he was building and selling twin Gas engines with electronic Ignition and mechenical advance long before DA and 3W were in the market. he has been our mentor for years and we spend a lot of time in his shop and on the field with him So some of us have been using large 120s and 140s for over 10 years and and we certenly Know how to set up our planes
however depending on a simple carb pump to deliver fuel in all sorts of High G menuvers is asking for trouble unfortunatly this is all we have
and yes some may argue that dead sticks is something we have to live with well in some of these large airplanes it's a big hit and miss unless you are at a sod farm good luck hiting the field or in most cases you are too low and allready in a stall so it just drops out of the sky now I am not saying that fuel injection is the answer and do not compare an os 140 fuel injectin on a glow engine to these I have never heard of a late model outboard motor on a boat just quit at mid trothle or load up on Idol
and we make sure that our engines are not overheating the head temp is always checked both planes had all the cooling baffeles this is simply the fuel delivery problem
and I could not care less if it was fuel injected or carberated or whatever just make them reliable Thats all we want and I'll be more then happy to pay not just a few hundred more I'll pay a thousand more if I do not have to touch or even see another needle valve again

Charlie P.

I've done dozens and dozens of dead sticks, but never had one where the engine quit for no reason. It's usually because I made a decision or action prior to the flight that caused the engine to quit. Most often it's because I'm in a hurry and hope the last settings are OK for that new day.

I have a Mariner 3.3Hp outboard that starts first pull and has for many years. But, I've never tried running it inverted or in a nose down attitude. At least not for an extended period. Now that little trooper is watercooled and always runs with the tank above the carb., at one g's or fractions above 1, and even then it occasionally kicks up clouds of smoke . . . but it does run.

Now, I have a Ryobi in a weed trimmer that is the most obnixious, stubborn, recalcitrant, mean spirited son of a mower that I ever met. THAT machine hates me, I know it. IF I can start it it runs fine. Getting the stupid thing to start is like entering the Temple of the Grail and facing the tests.

Personally, I still fly 'em up in the air and some of my best landings are dead stick. Causes one to focus and clears the mind. If you're flying below 50 ft without momentum and not in the act of taking off you have committed the pilot's first sin of running out of altitude, airspeed and ideas all at the same time. Speed is life.

Arthur K

With all due respect Charlie the only reason why we spend tousands of dollars on these 40% + Airplanes use the best most powerfull servos spend a ton of money to buy the finest full 3d kits like aerotech , Carden , or comp ARf is to fly them 5 feet of the ground do stall menuvers that no real full scale aircraft can do and put them in g forces unheard of because they are made for this and engine manufacturers like DA , 3W , ZDZ, sell these 150 cc superpowers for this pupose it is advertised all over this and other sites by these manufacturers on there own web pages and magazine ads are pictures of there sponsered pilots hovering a foot off the ground so we expect them to work flawless this is not some glow os 40's that the needle valve has to be adjusted every day and these airplanes do not fly like a carl goldberg sport plane
they loose airspeed awfull fast float forever and then just drop( without trying to sound like an arogant *****) most of us who fly these large aerobatic planes are very good pilots and have deadsticked hundreds of planes with no problem but this is a whole diffrent ballgame
Here is a little history just this past week in the span of seven days

Da 100 in a hanger 9 extra went dead stick on level flight at about 1/2 throtle bent landing gear
da 50 in a extreme yak new engine after 2 tanks on the ground dead stick 2wice the same day no damage
next day after checking fuel tank dead stick again in mid flight got her in checked everthing second flight of same day no problems
same day my 150 and bobs quit as I mentioned above at the bigining of this post we have yet to find a reason
it seemes every week on type or another gaser is having there share of problems and do not get me wrong I am not picking on DA it's just that we all use DA's at our field it is still the best of what is available

All I am saying is they need to come up with a better fuel and air delivery system

mglavin

My Feedback: (31)

I maybe outside the box to suggest both engine out scenarios described above explain the specific engine failure IMO...

The first one; inverted flat spin at idle: turn up the idle when you leave the ground a click or two.

The second; half throttle hover engine out: richen the needle and or allow the model to cool off in between demanding maneuvers. Be mindful of engine heat and ambient temperatures while performing sustained hovers, heat is the enemy.

These carbs don't care if their inverted or upright makes no difference. The diaphragm fuel pumps are ideal for our use as they do rely on gravity and floats. The fuel delivery system is always working with pressure when running.

Lastly I think the carbs work fine, are there better mousetraps I suppose. One way or the other there is going to be a downside.

You can't blame the carb if it’s improperly tuned and or not provided fuel. These are the two most commons reasons I note for engine outs. I have seen many and heard of even more perfectly good airplanes that were splashed because they ran low or out of fuel, what a waste.

Dick T.

My Feedback: (243)

I'll chime in here with Mike Glavin.

Another thing I notice with some in the gasser crowd is the constant needle fiddling (likewise in the glo crowd too). I can't understand anyone who has an engine in a 3D plane that hovers just above an idle and rockets straight up faster than the Shuttle, who tweaks the needles for "a little more power". I have seen it myself, then watched it sag or quit, then listen to the pilot blame everything else for the problem.

The more I spend on a particular engine/airplane set up, the more careful I am in checking the fuel delivery system and in tuning toward the lean side. If the engine delivers ample power while on the fat side, leave the darn thing alone. Besides, as the engine heats up from the hard 3D work. the richer setting is a benefit.

Aside from crash damage I would guess the majority of engines returned for service have encountered overheating from too lean settings for the task, or for "a little more power".

Arthur K

Michael this is not about bashing a product I was one the first to get a Da 150 in canada I have had my engine for 3 Seasons and I still say it is the most reliable of the bunch
I just want to know how many of us are out there not content with the engine technology available to us . We demand the best out of our radios and manufacturers provide it we want more robust poerfull servos hey they give us 330oz Titanuim gear servos ten years ago this was unheard of we get transmiters like mz 14 that can probebly make a coffie while we are flying So why can't we get an engine that we can take out of the box slap it on and never even look at a neddle valve or not wory about atmospheric presure changes we do not get up in the morning check the berometre get under the hood of the car and adjust the settings for that day. Heck I have not meet anyone yet that does not have one thing or another go wrong with there Gasers in the corse of a seasons flying, So please do not tell me what could have caused our dead sticks we can guess all that and yes I do push my trim up every take off and push it down every time I come around to land and Bob is no novice in hovering a plane he knows full well he can overheat the engine if he keeps it there to long and for the hundred times that I must have put that plane in a flat spin it was fine but this saturday it quit. And before any comes up with if you fly hard be prepared to loose planes I AM NOT UPSET AT THE FACT THAT I HAVE TO FIX A PLANE IT"S NO BIG DEAL
I just want to know is everyone out there happy with the Engines in the market available today or do we want a better more reliable product.

Arthur K

Dick the needle settings on a da 150 is and always should be 5/8 on the low and 1 7/8 on the high and this is where it has been for the last 2 years I do not know about some other guy's but most Da owners will agree with me that you do not play with the settings on Da 150s they are extremely sensitive lean out the low end one click below 1/2 and it will not Idle and the high is pretty much the same few clicks either way and it 's toast no most 3d pilots do not mess with needle settings we try different exhaust systems constantly looking for the most efficient props to mach our airplanes most of us stick with da recommendations in oil and gas mixtures and are pretty much religious in breaking in engines
Again let me make this clear I am not asking for the reason why we have dead sticks I know darn well with the things I do with my plane and the stress I put my equipment through I will end up with misshaps this thread is up just to seee if.... Am I the only puts in this sport that would like to see more sufisticated reliable bombproof powerplants and are willing to pay for it or are there more out there who think like me thats it

Dick T.

My Feedback: (243)

No matter how much you spend nor how great the technology, there are still going to be failures. EFI takes the guess work out of needle settings but even the finest automobile, motorcycle and aircraft EFI fail.

The current carbs are the most cost effective with high reliability, even by your own flight record.

O.S. EFI engines are great running and adjust themselves according to the elements, but they are comparatively expensive and neither failure nor idiot proof. And folks aren't stampeding to buy them either.

We are spoiled with high quality and reliable R/C technology. We carp about the one flight that wasn't perfect, overshadowing the one hundred perfect flights prior to it.

I don't disagree with your quest for better hardware, but it won't be bullet proof.

Arthur K

Dick I think it is time to upgrade these gasers this is just our human nature now I am not one of these ( buy an arf and go out and hover guy's )
I built and fly large war birds built all my planes some from scratch and some from kits and I spend an awfull amount of my time in this hobby
and if you look at the radio tecnology we have today cutting edge elctric motors li poly bateries it looks like there is something new comeing out every week in this hobby except for the large gasers For instance I spend almost a year building a war bird put 20,000 rivits one by one with a sringe and glue spend god knows on how many hours to come out with a perfect finish and the best powerplant i could get for it is a brison 4.2 an engine made out of Makita dolomar chainsaw head cylinder conecting rod and carb that has not changed in ten years are they reliable considering whats out there they are IMO the most trustworthy of all but I am still sending up an airplane that I spend probebly 300 hours on and trusting a 256 ball link and and a cheep plastic conector for the mechanical timing on that engine after all these years they have yet to machine a robust conection between the throtle arm and that mechanical advance ring this is what bugs me.

Albatross

My Feedback: (7)

Excelent point, that's way the radio is all about, use the flying modes (JR) or any other radio trick to avoid a potential flame out for instance during those slow flat spins.

One can picture this imaginary scenario happening inside the cockpit of that airplane. I will be constantly watching the engine gages and other than the gas gage the most important would be the temperature engine gage. I will be closely watching the progress of the temperature during the entire flying session knowing that I have an air cooled engine 2 strokes. Moreover this would help me out to decide when I must stop flying a prolongated hovering maneuver that overloads the engine and therefore increases the risk of engine flame out due to overheating.

Coming back to the ground an the real world, I certainly can't fly in the cockpit of my airplane and I don't have benefit of telemetry system. The RC pilot has to use his best judgment to asses those potential factors that lead to an engine flame out thus avoiding the lost of an expensive model. This is what make us RC pilots , we need to estimate the air speed during a landing approach , we need to estimate the distance and speed of our airplane, wee need to learn how the airplane "feels" when is about to stall, etc. By the same token, we need to learn when the engine is telling us that we are just asking too much or maybe prior to take off, any unusual noise any weird litle thing happening may be the only sign that something bad is about to happen.

The technology may help us, however it does not come for free. The RC airplanes might become even more expensive IMO.

Didier

I can understand that Dick Handson and Mglavin for example, don't see the problem of the chainsaw carbs.
These guys are so extremely experienced and have created a "natural feeling" for these carbs an gassers and therefore don't understand why a lot of people have problems with them.
My biggest passion is these big great 35-40% giant scale aerobatic airplanes but the disadvantage for me was that in the aera where I live 160 size glow engines are the top.....
2 Years ago I bought a 2 meter airplane together with my buddy, he choose a 3W24 and I choose a SM30 gasser engine.
Both engines have a Walbro on the backside of the engine.
After struggling one year with this very bad engine ( positive G-->running rich, negative G-->running lean and quit), I gave up and bought a OS160FX and I am very happy!!!!!
My buddy with his 3W24 engine is struggling now for 2 years, same problems as I have only he resist to buy an other engine like a OS160FX.
This problems has nothing to do with pressure problems but purely with G-forces in the carb, we experimented a lot.
Because the passion of the big gasser airplanes was so hard for me, I bought last year a 33% Extra with a DA100.
My mind sayed no but my hart says yes, If you know what I mean.
This engine was from the first start very reliable but the gas respons and the midrange burble was not acceptable.
After tuning the engine for 6 months now, the engine runs very good, reliable so far but still has some midrange burble.
I tweaked the low needle very, very lean just to have a good midrange, not for top power, I don't care.
It still is a little bit a compromise but acceptable.
Don't forget that I had to "invent" engine tuning myself, otherwise it was working much quicker of course.
If I look to the OS160FI of a friend of my, that is really, really nice, It is like an electric motor the gas respons is very linear without midrange burble and tuning the engine

Bottom line is that I really hope they will invent a EFI system, not only for reliable engine runs but also for a perfect midrange and gasrespons.
In the end gas engine manufactures will make profit of it to, no more stupid overheated engines to repair in warrenty time made by beginners that leaned the engine to much.
People that says it will be much more expensive, ofcourse, but If you already pay 5000 dollar for an airplane........

Arthur K

Now we are getting the Idea of this thred
you see I belong to a club Just started in Torornto Called GTA giant scale flyers all our members fly nothing but large Gasers
we all have at least 3 to 4 gas powered aircraft and on any given day someone is having a problem with an engine that was running perfect the last time they were out
and then something goes wrong one guy can,t hold Idle the other no top end the next one bad transition or flame out or loading up today it is too rich tommorow it is to lean
THIS IS NUTS ------Just imagine the first company that comes out with a fuel delivery system that is pretuned from the factory I could not care less if it was elec. enjection or whatever but it is set from the factory and we would not have to ever touch any setting just put it on the plane and go fly who would not pay a few more bucks for this
we spend tons of money to make our planes safe 2 receavers 14 top of the line servos Transmiters that can lunch the space shutle 300.00 for bateries 200 for regulators carbon fibre this carbon fibre that I mean come on and we trust it all on a $50.00 Walbro carberator did you guy's know that we can get rebuilt kits for a da 150 carb from a local lawn care supplier or get a replacement cylinder head for a brison 5.8 from a chain saw dealer Large engine technology in this hobby is in the stone ages thank god for electronic Ignition or else we would be all flying with extra 2 pounds of magnets

rmh

OK-- what would you do if your electronic fuel injection went on the fritz?
Likely same thing the mechanics at the garage do --R&R it
The FI for my old four banger Subaru -and it is a TBI not a MPI- is $ 500
Frankly my first BMW an 1800 back in 65-had a single downdraft Solex-and in 100000 miles it never missed a beat .
Carbs went out of favor due to an mandate from EPA.
Also MPI can tailor everything the engine needs -for a price.
A well setup carb equipped engine can deliver excellent low cost , long service . I learned carbs starting with Stromberg 48's and those things -properly setup delivered smooth performance (I also could lay waste to the new FI Corvettes with em).
If you want no problems and no learning curve on a model engine - good luck-
why not just purchase another engine as a spare-
Cheaper than going "high dreck".

jmiracle

My Feedback: (9)

This all sounds to me like tuning issues.....I agree with mr. glavin and mr. hanson.

I've only been flying gas engines for about 3 years now.....but only once (1 time) have I had a gas ignition engine flame-out in-flight.....and it was just as Mr. Glavin described. I had bumped the throttle trim down a couple clicks prior to that flight to help with slowing the plane down for landing. The engine then quit at the bottom of a blender......I pulled the throttle to idle right as I put it in a flat-spin......then all was silent.

I got it down just fine....but I learned my lesson.

With my DA100, I spent some time tuning it when I first got it....and haven't touched the needles since. It now needs choked only once at the beginning of my flying day. After that it starts on the first flip every time. By far the most reliable and consistent engine I've ever owned. I've run around 20 gal. of fuel through it this season and it has not even hinted at quitting in-flight.

Arthur K

before I get into any further I have to ask this question to mr Hanson
which gas powered engines are you curently using and in what aircraft are they in ?????????

Arthur K

You see mr Hanson my first fuel Injected car was an alfa 2000 GTV it too was a tbi and it was crap I changed the blody thing and put 2 weber 44's tuned them up and the way I went but my BMW 540 today has a multi port injection and it has 325,000 KM and the only thing I have ever changed on it is a presure senser
IT IS CALED PROGRESS
My first Jaguar XJR was a 97 with lucas electronics and it was crap my new one a 2000 model is bocsh electronics and it is great this is also progress
and probebly if the first few designed Aircraft engines with fuel injection will have lots of problems but eventualy they too will be as reliable as a new subaru MPI engine is today
Come on if we ask for them guess what THEY WILL BUILD THEM

Giw252

My Feedback: (4)

Gentlemen,

I've been flying gas burners for many years now and I would like to suggest an engine producer that you may not know. D&B Engines produced by Ken Baker are great running and reliable engines. My 5.1 83cc twin has the power of a DA 100. For you guys in the market for a new large twin check out D&B engines. www.dandbengines.com One flame out in five years and hundreds of flights.

Charlie P.

Understood.

But why do you think the "real full scale aircraft" don't attempt the same maneuvers? When you push the envelope you should expect tears.

(Perhaps it's no concidence that word means both "to cry" and "to rend"?)

I'm from the "fly 'em like you were in 'em" instead of "fly 'em like you stole 'em" school.

Arthur K

Charlie please get with the program
what we do is not just a hobbie it is a sport we built these planes and set them up for the purpose of flying them in high G's 2 feet off the ground and in stall
the planes are designed for this purpose the engines that we buy are designed for this purpose
I have a few vids on this site and when you see me fly my thunderbolt I do not pull walls and try knife edge with it I fly it like a war bird
and when I fly my Edge I fly it on the edge

AND THIS IS NOT ABOUT CRYING BECAUSE I SCUFFED THE COWEL ON MY PLANE
you got to understand I built them in lightning speed and I can fix anything the ground can throw at me and fix it like it was new
so i realy am not upset with a few scrches and never cry about a crash I am of the scool if you fly them you can crash them so no tears here

I want to hear from people that do fly 40% 3d aircraft and see if they are happy with the powerplants available to us that's it
do not need to know how to tune an engine or how to fly dead sticks or how high I need to fly( now I am going to sound like an arogant jerk)
but I am not intersted in a leson on how to fly a cub or tune up a g62 been there done that and can probebly write a book on it

I want your opinion on simply are today's gas engines good enough for our SPORT OF GIANT SCALE AEROBATIC AIRPLANES or could they improve the reliability
certainly the power is there they weigh less then ever but are they reliable enough or can we get better if we all ask for them
it seems to me that everone wants power more power at a given size and no one iis asking for reliability better fuel delivery or smoother transition better heat dispersment
easier starting less atmosphere sensitive
IMO these are just as important as power

Scar

My Feedback: (3)

What's your solution?

If I got the request, I'd probably get an electronics department to turn out an ECM, to control the EFI or throttle, with temperature sensors, airflow sensor, pressure sensors, timing, throttle servo and mixture control. Using off-the-shelf sensors, the system would probably have about $65 (cost) in sensors, and the first ECM (counting development costs for the first engine size & type) would cost somewhere upwards of $250,000 (including the mapping for that particular engine.) After that, subsequent model engines could be mapped for around $25,000 each. (That $25k may be a bit high, the $250K may be a little low...)

The ECM would be priced according to the market. This would, by gosh, work, now can I get my money back and a profit? How many would I have to keep in inventory?

Other engine development guys can chime in, here, I'm sure some of you are reading. How are my numbers? Could we create this system (in our already existing multi-megabuck development facility) for around $300K? Could we price the result, for a DA100, under $2500 and get our money back next year? $7500? $10k?

Yes, it would work (although we'd have to detune when head temperature gets too hot, causing a drop in power....) Could we sell it, and make it worth our while?

Or is this a solution that's begging a problem?

Dave Olson

tsekoa

My Feedback: (2)

Arthur,

Are you using non oxygenated fuel? That is to say 100% real gasoline. No ethenol. Your engine will run cooler and produce more power. How about the oil you are using? I use only two stroke motorcycle racing synthetic oil. Also you could try attaching a tube from the pressure regulator on the carb to the inside of the fuslage so the pressure at the pump will not change due to airspeed or prop wash.