What? Isn't this supposed to be a WWII sim?

Why do we need this when there's perfectly good examples flying today.

To be devil's advocate, do they use exactly the same fuel, etc? I can see what you're saying, a mark 1 spit from today is better to compare to than a seafire, but it's hard to find suitable videos.
Just my thought. Personally I think it's best to average out the effects seen in some videos, and then base this strongly around historical references. The pilots from the time would have had a pretty good idea themselves, and many have documented the effect ;)

Basically all internal combustion engines are the same in the compression chamber. As far as any visible flames coming from the exhaust stack. A properly burnt mixture may not show any flame at the stack, because the fuel was burned up already during the compression power stroke firing. A cold engine on the other hand, would be showing colored flames during the exhaust stroke for a bit...kind of cool feature, but I would prefer it only on the start up in game.

Right now I´m just thinking why doesn´t Oleg call Duxford and tells them he the master blaster that will get more visitors to Duxfords Flying Legends all he needs from them is the different colours of of different planetypes with the engine in different conditions and various lights.

Better then us guessing around if this is the right fuel/footage/idea/whatever.

Good greif Alpha, you have quoted me but havent bothered to read what I wrote about the vid I posted "READ WHAT I WROTE" :rolleyes:

I read it

You didn't read Olegs response to earlier similar video.

I even quoted Oleg and what he said to earlier similar video of yours

So whos not reading the thread posts ?

If your are interested in this thread read my earlier posts they accurate from years of experience.

My last post in here regarding this, I'm done with it.

Wrong plane wrong engine same effect I have seen many times on MKI......... but value to this thread...........zero

http://www.youtube.com/watch?v=frTA1...eature=related

Thanks for letting us know you are done with it.

Woo hoo.. yet another update thread ends in name calling..

Too many people who think that opinion and fact are the same thing.

Come on girls, play nice. I have a handkerchief if anyone needs to dry thier eyes.

:) Regardless of what mark,make and model, BoB is the first of a line of sims which will incorporate different types and locations.
Any useful info is good for the future as well as today.

flames red or blue ... whatever ...

it only needs to be deemed down a bit and it is cool

or ....

use the modification that has all the nice different stages if you like ..

but please !!!!

can we move on ?

can we? eh? :)

Well said! ;)

I think all of you are taking this way too far. Blue flames instead of red or yellow and that's about it...Blue. Even the Daimler Benz flames are about the same blue and I don't think Maddox is going to fart around for the next six months getting his flames just so. Going back to 1940 to compare high leded fuels and their flames with today's low led fuels and their flames..Hilarious! Is it a flight sim or a flame sim?

Well done, Oleg et al! Storm of War is looking very nice indeed! I'm sure the community in large will really be thrilled with the attention to details. I know I can't wait!

I have a couple of DeviceLink questions (apologies if I've missed a relevant thread on this topic):

1) Will Storm of War support DeviceLink or some similar interface for data logging and sim-pits?

2) If so, could it I be so bold to make a humble request for a few parameters in addition to those currently available in DeviceLink 1.00?
- True Airspeed
- True Altitude
- Outside air temperature
- Static air pressure
- Angle of attack
- Total thrust force
- Total drag force

These parameters would be very useful in evaluating aircraft performance (specific energy, lift curves, etc.) and are similar to those parameters taken (or derived) on test flights of real aircraft.

I know what you mean.
I have always viewed it like this: there will always be forum members with specific knowledge in certain subject areas (like me with my RAF flight-gear collection) and when the teams asks for help in that area, there will usually be a lot of info, but not all of it is necessarily needed.
However, IMHO, more is better than less ;)
But I agree, it's just an effect and one won't notice if there is just a tiny bit too much blue...

Nice flamebait Oleg, it worked.

yellow/orange/red at startup or when damaged

blue/white during normal operation

/thread

:grin::grin::grin: !!!!

Oleg must be laughing outloud at home tonight: Look at this , honey, ! I told you it would take less that 2 days before they get at each others throat arguing about..guess what this time ? exhaust flame color at night!!!...hahahaha!
Next week, I will ask them about tire pressure....It will be a carnage !!! Can't wait till next update !

;)

I agree that the color is somewhat too yellow (I agree with what Adman said above), but the biggest thing I've noticed is that the flash from the exhaust on the side of the fuselage is overdone. It should be minimal to nonexistent.

If I was Oleg I would post up-dates that, I knew, where flawed...that way the nitpickers are too busy squabbling over "red or blue flames" (example), as opposed to moaning over release dates, computer spec's or whatever subject they think will get the forum community in a "tizzy"... lol


Its time to keep the "kiddies" busy...the adults are working.

;) ;) ;)

Sorry, I was a little harsh Phillip lol

I'm still imagining the picture and laughing...A LOT.:-P

I'm trying to think back to the 60s. wasn't gasoline a yellow colour back then?

Ha ha well even with mid forties I then hope I will never become an "adult" as you put it.
Going by some posts one could drop all input, at the most only writen signs of awe are acceptable......Thank god your type is not an admin, or forums would be a dead place.

I don't see this as a squabble at all. It's been a useful and interesting discussion with opportunities to learn new things. Oleg asked whether the flames were too yellow on the running engine. From all the evidence and experience posted here it is clear that yellow flames are generally only expelled on initial start up or when the engine is damaged in some way.

Correct me if I'm wrong but I haven't seen one video here showing regular yellow flames coming from a running engine. All are either blue or red once the initial startup is complete. Also no night shots show the side panels being lit up by the exhaust flames. That backs up my personal experience from 2 night runs on a Lanc and a Merlin Spitfire.

I think the thread has done its job well.

Oleg, avoid forum arguments about start up flame colours by posting up a video of a dogfight with nicely weatherd aircraft.This would bring us all together in admiration of your fine work, and it would be a great crimbo present to all your loyal fans and supporters :grin:

oh and without any place holders if possible.

http://www.youtube.com/watch?v=7GDqmHXFgo4

Seems to be a sort of orangey brown on this one...

+ 1. I totally agree.

It's the first time, since about 5 years, that i post. My first few words will obviously be for Oleg : I love you !!! Oups sorry, i exaggerate a bit ! ;-) But i love your work. Long life to you and your team... All your work philosophy is perfect to my mind, and i'm sure BoB will be astonishing, awesome... Please don't change anything to your working way, you and your team are fantastic ! However, that's right it becomes to be very hard to stay patient, because we wait for some years and now, we know that the release date is for soon (please don't tell me something else or i die at this second). But at least we know that we wait for the best simulation ever ! And yet many many many thanks for your kind work, for Il-2, for your attitude. You're the best. Because you do better than that we could dream... Thanks again.

Very nice example showing the persistence of the blue flame at night and why nightfighters like Hurricanes had the exhaust stack guard over them.

That's a Griffon engine btw but I expect the Merlins were similar especially according to anecdotal evidence from the actual pilots.

Wow! I'm not an expert on this but the flame and smoke effects in this video are very convincing. I'll be very happy with similar effects in SoW.

I wanted to post this before but just didnt have time:

As Oleg explained, the flame output of an exhaust is affected by factors like temperature and pressure. Flames visibility is due mainly to lighting factors (it'll be harder to see flames on a sunny day), but they're always there (bear in mind that what you see is the output of the avgas combustion straight from the combustion chamber!).
Exhaust fire shouldn't be confused with backfire though, which is an external combustion of a too rich mixture which causes flames like this
http://air-and-space.com/20070818%20...20crop%20l.jpg

Oleg, I love the work you're doing, the attention to details as usual is surprising and comes from a man who obviously has experience with aviation, my humble suggestion is to keep the flames towards the red/blue spectrum more than yellow, since the temperatures involved are far higher than a "yellow flame" when it comes to exhaust output. Another important aspect is to keep them subtle (in terms of transparency/alpha channel) but visible from distance (thinking of the Zerstoerer night fighters spotting the engine exhausts of Lancasters at a certain distance).

About map.
Dimension are enough but i agree about Duxford. Would have been better have it.......... Why? You know it.

However my question is. Would be possible to fly this map also online or we'll have dogfight style maps with islands ecc. ecc.?

engine management
 

Hi Oleg and thanks a lot for the weekly updates !
looks like we're gonna have a wonderfull flight sim.

it's my first post, and please apologize if the subject has been already chatted, i haven't found the answer.

QUESTION:
- The screenshots show fuel tank selector knob in cockpit... will fuel cunsumption influence centering/trimming of the airplane ?

- a suggestion: if this very realistic management is really implemented in the released game, it would be nice to have precise doc on the DVD, i.e. admission pressure and rpms for different flight condition, time to deplete a fuel tank,... the kind of data that is in the flight manual :)
otherwise even solo flying shall be difficult !

-will we have random failures ? (not only engine, but gun jamming, radio down, gear or flaps innoperative...)
they might have been common it the crash-programm building of materials during the war.

Thanks a lot
Alexis

NB: i don't mean there's too much realism, i'd just like to have the information to run "smoothly" the engine.:-)

You are right Stutts. In every new Fryday Update we do learn a lot about WW2 from lots of well informed members...:-)
But it doen't take long before somebody disagrees with someone's opinion, and instead of politely making a comment,replies with a harsh and useless remark, often beeing a personnal attack....As a father of 2 young boys, I think that my overall patience :rolleyes: is well challenged everyday in the real world, so when I come here to enjoy good company and admire Oleg's work, it is very irritating to witness such a behavior... And in this forum , it is exactly like at home : kids play togheter, happy with the new toy, and you can be sure it won't be long before screams and tears...;)

Salute !

No.3 : Should be. If I remember it right:) I don't excactly know what things will random fail, but I think some things.

No.2 + 3 : Would be very nice:grin:

I wonder if grass will move in prop wash. I was kind of hoping in the first video that that one Spitfire would swing right around and blow the grass.

Flame color...
 

So, some may know already, but "proper" color of flame is not just what you like, but depends on many factors including Fuel type and Mixture, and mixture varies by type and amount of boost. Actual flame color is relative to combustion temperature and oxygen concentration. Generally speaking, the leaner the mixture, the "bluer" the flame, and the richer, the more yellow it is. At full boost, you tend to run richer to avoid burning a piston, and it should be more yellow. At cruise, it should be leaner, and thus bluer. For game purposes, I would probably have a couple settings - yellower for start up and full power, and bluer for all other settings - Important to note, but generally the only time you see any flame at all is on a missfire. If the engine is running in tune, there should be little missfires, and thus not much flame (although even a 2% missfire rate is still about 11 missfires/sec on a 16 cyl at 2000 rpm if I did the math right). The flame occurs when the unburned mixture hits the hot exhaust and combusts in the exhaust stack.... This is the general truth, but I'm sure experts could refine the exact details.

let's not forget that the flaming alternation of different exhausts is more visible at low revs/idle. When the engine is on cruise the blue flames are more constant from all the exhausts, as the engine is working at higer revs.

Agree!!
Thanks for update Oleg ! :)

This has nothing to do with the engine running normally it's just raw fuel on fire. That engine probably isn't even running yet. The wind from the prop would blow it out.

http://www.youtube.com/watch?v=EoyN29O8UoE

That sounds all very good but please show us a video where these yellow flames are being ejected by a running engine or point to the entry in the WWII exhaust flame colour chart where yellow flames are referred to. That chart covers everything from weak to rich mixtures and a whole lot of other scenarios including engine damage. Strange how yellow flames don't even get a mention - orange on a damaged engine but everything else is red and blue. I know it's for an Allison engine but I can't believe it differs much from any other inline carburated aero engine.

The only yellow flames I've ever seen are from raw fuel burning in the stacks of a flooded engine and an initial burst of yellow/orange flame when the engine first fires up.

I'd be happy to be proved wrong as I like the pretty yellow flames :grin: but the overwhelming evidence so far is against yellow flames from a running engine.

The big question is this: Will be be able to over-prime the engine in the game?

That's a very good question. I think because of the fuel injection of the German fighters the Allied aeroplanes will have more fun with the flames.

Half right ... once an engine fires the manifold vacuum and exhaust pressure extinguish any carby or stack fires.

The main, well documented, issue on WWII war-birds was the glow of the hot manifolds at night, interfering with pilot visibility (especially in high mounted manifold designs like the hurricane and spitfire) and making the aircraft a target to night fighters. A number of different design features were tried to mask this manifold glow.

Yes, you have a point. It isn't the exhaust that is glowing, but the exhaust manifold. Inevitably this will be at a significantly lowe temperature than the exhaust itself, so where the exhaust is flame may be blue, the manifold will be yellow or red.

Oleg,

If you havent already recieved enough info at this point, I want you to know that the flame color coming out of the exhaust of a running engine like that would be more blue! than red or yellow. The flame is burning hot and mostly clean, so it comes out with a nice blue flame at night. In the day, you wont see it.

On engine start, the only time you will get the yellow/orange flame out the exhaust is if the engine is too rich and it spits out unburnt fuel that burns exiting the exhaust stack. In that case you will get a lot of orange/yellow fire coming out for a short time. I was on the wing of a P-51 when that happened and it does get warm...

Note: its easiest to over prime with the electric fuel pumps found on P-51s and the like.

*edit The short stacks in most of the videos lets you see a lot of blue flame...more than if the full length stack was in place. If you leave the exhaust as is with no blue, you really will be misrepresenting the way exhaust looks coming out of the stacks at night...

http://www.youtube.com/watch?v=g2gef...eature=related
This video (previously posted) shows what I would expect to see coming from the exhaust at high power settings at night...see it at 0:30 video time

http://www.youtube.com/watch?v=UDZmq2VrcNQ
This video shows over priming at about 5:30. His first couple of attempts to start were underprimed and he didnt keep it running with additional priming.

Also, when you go from high power to low power rapidly, you will get some light popping and orange flame as the rpm comes down.

Good luck with your great project!
Chill31

*edit, looking back at all of the posts, it looks well covered!

well first of all is mixture, not raw fuel, on fire; second, if you READ what I wrote you might well see that that's exactly was I was talking about ;)

...what do you mean exactly?

When burning fuel in the cylinder, if we're talking about an ideal process - you need exactly the same amount of fuel and air in your mixture. Since space in cylinder is limited, there is only so much air and fuel you can put in there (if we're not talking about turbo or supercharging). And certain amount of fuel requires exactly certain amount of air (I forgot the exact ratio but I can dig it up if you want, I have it one of my books).

The biggest downside of carburetors is that they can produce such ideal mixture only on certain RPMs, or RPM ranges. While direct fuel injection is much more flexible and can provide the engine with better mixture on all RPM ranges.

I am talking theory here, but I believe this is what Richie meant with:

well not as simple as that.

The ideal mixture is about 14:1, also called lambda=1.

But if you have certain parameters of use like
RPM
accelaration,
Airtemperature high, low
Airpressure high, low
Cold motor (less evaporating fuel in cylinder and thus richer mixture needed)

etc. etc. etc.

you get lots of changes in actual needed air to fuel ratio. Many FuelInjection Systems are a not specified to recognize all those factors, where some really complicated carburators do.

So it´s not that simple one could say:
Fuel Injection is working better than a carburator in terms of providing the RIGHT mixture for all operating conditions.

Damm, I think I flooded her!...

Now you know the real reason, why I fought so hard for realistic start up's:-P .. Flames

erm... no, in a nutshell: mixture has different ratios, which need to be varied according to your altitude (leaner/richer mixture), besides a 50/50 mixture ratio would probably send your valves into orbit ;) (Disclaimer: just wanted to make a joke here, please don't take it literally and start posting copy/paste engineering blabber..)
What Richie said just doesn't make sense: engines won't produce different flames if they're direct injected or carburator injected. Or maybe I got it wrong in the first place.

I have a sneaky suspicion that Thor might know what he is talking about when it comes to engines...;)

..I bet I know a couple of things too ;)

Amen :)

ideal mixture is still basically the same at any altitude. The difference is that the air density decreases as you go up, requiring mixture adjustments to maintain the same air/fuel ratio. Some planes had auto compensation, but most did not, so mechanical tune and operator capability also come into play here.

smoke effects
 

Well, if this colour is the result of computation alone, I think it is remarkable!
Fantastic modelling which just blows my engineering mind away.

If we are talking realism, I would say that a carburated Merlin engine starting up from cold will emit yellow flames because the mixture will be rich. After a few minutes, i would say the flame would go blu-ish?

A Daimler Benz of the period had fuel injection so i would imagine the exhausts would be blue-ish from the start as the air-fuel mixture would have been slightly leaner? Probably 'blipping' the throttle would make the burn 'leaner' as the blower increased the air flow, so it probably went bluer?

Are there any surviving RAF groundpersonnel (engine specialist) who would know? I might drop the Battle of Britain Memorial Flight a line... but it's almost a trivial detail, isn't it?

Can't wait for the game to come out, but I'd rather wait until Oleg is happy to release it, rather than rush it.

Marx

I'm curious which injection systems you are talking about.

The main problem with a carburetor: it's very hard to distribute the mixture to all cylinders equally. Plus fuel injected engine are less prone to icing, they have a faster throttle response and are easier to start when cold.

I dont think your really getting my point...lol

Almost correct. The ideal stoichiometric mixture ratio is 14,7:1 => or 15:1. When we're talking in mass, not volume.

There are two different lambdas in petrol (Otto) engines: lambda(air) & lambda(charge)*.

*not sure if this is the correct technical term in English.

In a petrol engine lambda 1 should always be constant (=1), whereas lambda(charge) can go up to 7 (with supercharged and turbocharged engines), otherwise it also equals 1.

Lambda of 1.0 is at stoichiometry, rich mixtures are less than 1.0, and lean mixtures are greater than 1.0.


Like Azimech, I am also curious of what carburetors are you talking about. The advantages of direct fuel injection over carburetors are numerous. If not, car engines would be using them even today. ;)


Fair enough. I forgot to write one thing - at ground level. Or even better: at 20° C & 1,013 bar (Standard atmospheric pressure: the conditions at which every engine is constructed and tested).

As for the rest (at least to my understanding, I am more into car engines), there is no such thing as 50/50 mixture. Maybe that is a phrase used by pilots and maintenance crews - they usually don't follow correct technical terms anyway. What I am trying to say (and to comment on your reply), there is an ideal ratio needed for the fuel inside the cylinder to burn most efficiently / completely (as previously mentioned). As you go higher air density is decreasing. Thus (in non supercharged engines) you need to lower the amount of fuel inside the cylinder to achieve the desired ratio or else you risk engine damage and various other things I do not want to get into now. The added downside of that is that engine power drops as well. To compensate for that - superchargers were invented. They compress air so that you can have the very same atmospheric pressure inside your cylinder as if you were flying on sea level. They can also be used to increase engine power (this is the easiest way to do it) - compress the air enough and more fuel can be put in the cylinder.

I could go on, posting diagrams, formulas etc. - but even 100 posts would be enough...

Anyway, what Richie meat was something else. With carburetors you can't get this ideal stoichiometric mixture ratio of 15:1 throughout whole RPM range because most carburetors are tuned for a certain RPM. This results in imperfect chemical reaction when fuel is burning inside the cylinder - hence probably more variable flames coming out of the exhaust, especially when changing RPM.


Absolutely true. What I posted above. ^^


I sure hope so... ;)

My Statemant was you can´t say it that Easy: 'Fuel Injection is working better than a carburator in terms of providing the RIGHT mixture for all operating conditions. '
Not which Technologie is best used to gain the goal of ideal mixture under all operating conditions!


Let´s say youll have a Pierburg 4A1 Carburator with ECU for fully closed loop control of a 3-Way Katalyst System and you compare it with a early k-Jet-Tronic, guess which one is more sophisticated in terms of providing right mixture for all operational state.

Now youre talking about a difference between mixture is built internal Cylinder vs external like in Intake Manifold or Carburator.
As long as you are not building mixture via direct injektion you always will put extra parameters to be recognized.

Thor, I used the 50/50 expression cos you mentioned "half and half", sorry, nothing really technical there ;)

I have a fair experience with aviation piston engines (I was lucky enough to fiddle with 2 strokes and 4 strokes Rotax, Gypsy Major, Continental, Lycoming, P&W Wasp and lately I started to get acquainted with the RR Packard Merlin), but I am no engineer or techie, I am just a flier who's interested in knowing what's happening under the bonnet in front of his nose..

I am not entering in the merits of lambdas or mixture ratios because they're peculiar to the engines and aeroplanes (and as you said 100 posts wouldn't be enough), all I can tell you though is that yes, in theory a direct injected engine like the DB could be more "mixture efficient", although carb engines are handled according to strict parameters, so you would hardly notice any difference in the flames colouring.. if Oleg managed to implement a flame colour changing according to mixture values then this would be a boomer, cos we'd be able to adjust our mixtures by looking at the exhausts and might also be able do diagnose engine problems (i.e. red exhaust flames and sparks coming out would mean a bad, bad day.. or in case of radial engines, where the exhausts are normally connected via a ring exhaust, an intermittent flame from the main exhaust would mean misfiring cylinders etc..).

Come on Oleg, this is quality material we're delivering you here! ;)

It is our target. Will be or not - we will see. We have a lot of such branched targets that should be done. Some are hight priority, some - not due to time that it may cost.

First I would like to say how much I envy you for the described experience. I am much more into theory, calculations and various physic laws related to engines. Unfortunately I have very little time with real engines. I did say 'probably' more variable, so this means that someone who is also an engineer and has the experience should have to come here and verify this in practice.

I am though, more inclined to believe that this difference in flames is almost invisible or not noticeable when comparing them with fuel injected engines of the same era.


Agreed. :) I see that Oleg has posted while I was writing my reply. Very nice. :cool:



Alright. It may not be that easy to claim that (especially when comparing mechanical fuel injection with carburetors), there are advantages and disadvantages of both - but from technical perspective and engine development advancements (especially in todays road vehicles) direct fuel injection is light years ahead.


The K-Jetronic lacks proper feedback to adjust the mixture because it doesn't have a lambda loop or lambda control. The biggest advantage of 3-Way Catalyst System (lambda control) is that engine can adjust to different types of fuel more or less automatically. It does not fix the main flaw of carburetors - inability to provide ideal mixture on all operational states.

However, mechanical injection could do only so much. Before ECU & lambda control were implemented.

Direct fuel injection coupled with specialized piston and cylinder head shapes to further improve fuel oxidation (burning) by creating swirls and tumbles (idling at low RPM even with high lambda values, up to 3.0) - is a light years ahead from any carburetor...

Oleg, dear old friend Oleg, if your next project was to put wings on a lawnmower I would still buy it! :grin:
You guys at Maddox delivered quality, and I know you won't ever let us down, keep up the good work guys! :)

it's a dirty business, hands always covered in grease, oil and cuts, but when you feel 1650HP growling in your guts, swinging that big propeller 10ft in front of you, 12 cylinders furiously roaring in all their power.. well it's well worth the dirty hands ;)

..The truth is that I like physics but I've always been rubbish in maths (I always lose a + or a - somewhere..).. LOL

Looks guys we want them to ship the game this decade..with all these inane requests it will never get done. You just gotta realize in the end its a simulation game..not real life. Once you come to terms with that your mind will rest...:grin:

I agree with Wildone,next we will be debating on what colour shoelaces the pilots wore.It's been a long enough wait for this sim and if everybody keeps going all Frazier crane on every little detail,Maddox will go broke trying to please all the anal retentives.

Now you're just talking dirty...

For me it is the other way around - I was always better in maths than in physics, but loosing a '+' or '-' is not strange to me either. :D



@ wildone & pencon: What we have been discussing here on last two pages are basics (of basics) of how internal combustion engines work. The mere fact that Oleg is considering to implement something like variable exhaust flames dependent on the mixture ratio is mind boggling. Let alone the individual cylinder modeling that has already been confirmed. Simply phenomenal work Oleg & co.


Before this gets more OT I will get back to the subject...

I wonder if the proper firing order has been simulated as well? Judging by the amount of details already shown, I would be surprised if it wasn't.

rumor is that game ships with a timing light and cloth map

Ah, I thought we were comparing WW2 carbs with WW2 mechanical injection. Because the Pierburg would probably have a hard time compared with Bosch Motronic, itself already 25 years old. K-Jetronic is very simple indeed.

I don't really explain things very well. I think that fuel injection is a much more precise system than a carbureted engine and much less likely to flame up when being started. In all of the videos I've watched of 109s being started not once have I seen one have a stack fire. That's why I said I thought the Allied pilots will have more fun with the flames and over priming than the Germans will. Does that make sense? Put BF 109 in youtube and watch 109s start.

Did you forget that Oleg himself requested the community to talk about this subject? Post like yours is the useless ones.

Well it really doesn't really matter if we go over board because he can pick and chose what information he can use and what he likes right?

Hopefully we get some nice christmas special friday update with release date, publisher name, awesome effects video and more. :grin:
I can't wait.

Never been into an aero engine, but I work on lots of old stuff. Everything from a Model T Ford to E-type Jaguars and a Lotus 11 LeMans.

Actually, driving the very early cars has much in common with early aircraft. The carbs are very rudimentary, as are all the other systems. They require constant input from the operator to be at their peak. Every gross change in throttle setting demands a change in mixture and spark advance, and it all changes as the engine warms. The settings you left the shop with will not be the settings you come back with.

It's a type of driving I really enjoy as it requires actual thought and input.

These are my thoughts as a steel fabricator. Using an oxygen acetylene cutting torch as an example... A very rich mixture of gasses coming out of the torch is Orange with much Black smoke. A high oxygen mixture is Blue White.Setting the mixture At the optimal point between an Oxidising flame and Carburizing flame is ideal.

I believe that effciency in an engine may be measured thus, and exhaust coulor be matched accordingly.

Thankyou for your patience

334th_Gazoo

The point is.. Is it running Lean or Rich?

Carby mixture settings have nothing to do with the stack flames on startup.

Carburetor aircraft engines commonly have a hand priming pump like the one below out of a spitfire:

http://www.spitfirespares.com/spitfi...40%20small.jpg

The pump injects fuel directly into the carb barrel or intake manifolds. Pumping it too many times before cranking the engine results in an excess of fuel and exhaust stack flames can result.

Right. If you look at all of the engines in the videos...in they dark... they're all blue. By the chart that was put up if the mixture is right and the engine is running perfectly the flame should be blue with a lick of red at the end. If you stood right up close maybe you could see some red.

http://www.youtube.com/watch?v=QhFAw...layer_embedded


http://www.youtube.com/watch?v=Xs_qt...layer_embedded


http://www.youtube.com/watch?v=4ZzvKCQwWj0

True. We should compare the same engines of the era. I've updated my reply two pages back.

Sorry Mr Maddox, but does that mean that you'll take the members advice and make exhaust flames blue?
As there is no evidence at all for yellow flames?
Thanks.

How did you get that?

The reply you quoted was related to a question about modeling individual cylinders in an engine to get authentic simulation of misfires etc .

There is evidence of yellow flames on startup and also if the mixture is incorrect...

Yellow flames on startup..agreed.

Yellow flames from running engine...please point me to this evidence, I must have missed it.

Thanks

We also have no evidence one way or the other for a running engine with longer exhaust stacks installed, as the Spitfire Mk. I has. All of those videos depict engines with very short exhaust stacks; Like so:
http://www.williammaloney.com/Aviati...austStacks.jpg
Instead of like so:
http://www.hyperscale.com/2007/featu...ges/Spit_6.JPG

exhaust flames
 

I've been working with planes and, at least in the case of radial engines, I still remember how amazed I was the first time I watched a ground test at night : the flames at full power are definitively white with a blueish end ( with the carburator and ignition tuned properly ) and they extended more than half the fuselage!!! ( the plane was a biplane used for cropdusting, with radial engine and one exhaust stub by the right side ) to give you and idea try to find pictures of Hurricanes used as night fighters... they had to add an anti-glare panel just ahead of the cockpit, and the streaking extends beyond the cockpit ...

Again, very interesting flame patterns / colours on rpms on this meteor ...

http://www.youtube.com/watch?v=D7WS5...eature=related


Also interesting LACK of flame on this merlin, packard I presume, fuel types on both vids...who knows.
http://www.youtube.com/watch?v=-mQRJA5W8CI

Wow, this thread is hilarious! The whole thing has been explained several times and still people argue about nothing. It makes me glad that I've decided to spend much less time here. See you on Friday, Oleg.

this is no CSI, no evidences available, only the laws of physics ;)

Once again, we need to make a distinction between startup backfire and exhaust flames:

1) on a cold engine, backfire happens for overpriming/bad magnetoes not delivering regular sparks at low revs; on a hot engine, it happens for the same conditions of a cold engine plus the hot exhausts/outlet valves/combustion chamber/carbon residues, who can ignite the non burnt mixture. In both cases the result will be a "cold flame"(as in relatively low temp flame) which will roar out of the exhaust (and warm up the combustion chamber a bit!) in a spectacular fashion. Backfire is more dangerous on radial engines because the flames can linger in the exhaust ring outlet and pre-ignite the mixture in the combustion chambers (blowing up cylinders/valves/spark plugs).

2) exhaust flames are the result of a correct combustion in the chamber, and because of the temperatures and pressures involved, they come out as hot flames normally (blue flames).

If you have the movie Tora Tora Tora have a look at the carrier takeoff sequence to see a good examples of blue flames in action.

this is perfect example of a badly maintained RR (the former, whose owner/operator should be slapped in the face...repeatedly..with a big spanner...) and an engine who's heavily modified (that's Strega from the Reno Races) and maintained to perfection.

Yes, sure, but keep in mind this a Meteor tank engine, derivated from a, but not a Merlin! So it is easy to imagine it was not that well maintained for a track vehicle use, that it may have had a much harsher life than an aero engine, and also the sparking system is different etc etc...
Besides it is running on a bench just for fun, driven by UK amateurs which are not swimming in money like the Strega people...

So please, a bit of moderation would not be out of place...

JV

One can clearly see that No.5 Cylinder on the left side and first No. 2, 3 and 4 then only No. 3 Cylinder on the right side have a different exhaust flame (red-orange vs blue-white).
Later the different exhaust temperatures are clearly seen.

That Seafire vid has a single yellow burst from each cylinder then it all went blue. I think there's evidence enough on here for Oleg to get it right.

Just to be accurate I'd stay away from any race aeroplanes. God knows what they're using in those things to make them haul *ss like that..nitros, alcohol. They're forever blowing engines in those races.


http://www.youtube.com/watch?v=0vniz3zXf4g

Well yes, the thing is not the same, pistons were casted instead of milled, components were made of heavier alloys etc.. but the engine would still run fine.
If you love engines you don't run them "just for fun", because one day they'll get rare and then who's gonna have fun? The engine is obviously not well carbureted, besides giving it a sudden revving just to have some flames spurting out is just plain stupid.. that engine could be used in a tank restoration, and not as some "fun toy".

Sorry if my opinion is offending you mate, but hey guess what, we live in a free world... :rolleyes:

yep, nitrogen, ethanol, water injection.. you name it!

oleg loves yellow because it is 1c company color
exhaust will stay yellow :grin:

ROTFL!

BTW, 30 pages on the color of exhaust flames ... a detail of an isolated short event ... OMG! Your monkey is really really bad guys ... :D

Not sure why people make comments like this. Oleg specifically asked for input and he got it.:confused: