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Schmouddle-WT
05-29-2006, 01:22 AM
Dear Oleg,

We have started testing a dynamic online DF campaign (DCG+IL2SC) and one thing brought our attention to a possible bug.

While flying a I-16 series 24 in far-to-ideal conditions, my engine kept quiting due to turbulent air even when flying straight.

I have to say if there is a turbulency so powerful it makes a negative G momentum long enough to make the engine quit it would be a major windshear, not a turbulency. Such a windshear is quite a rare event that average WWII pilot did not experienced it in his whole career. Turbulency is a short (and sometimes powerful) event but in any case it is not able to make the engine quit (unless the plane breaks up).

Secondly, I may not have any real flying experiences, but a common sense tells me if the engine has all it needs (spark, fuel, air and spinning momentum), it would not quit, it would just cough and keep running.


I would compare it to driving my 1988 Skoda Favorit fast over a beaten-up railway crossing somewhere in Central Bohemia - I may break the axle, I may hit the ceiling with my head hard but unless I hit the bottom of the engine it would run fine all the time - it is a carburetor engine.

May I have any reply from you and comments from real pilots?

(copy to Oleg's address sent)

heywooood
05-29-2006, 09:32 AM
the I-16 has a carbeurator for fuel/air intake, so it is affected by gravity...negative G' like sudden nose down pitch adjustments will cause fuel starvation and engine stalls - other types of planes with fuel injection systems are not prone to this. To avoid engine stalls in the I-16 you can roll inverted before diving to keep positive G's in he carb...or try pumping the throttle back and forth just as you hear the motor sputter...sometime that will keep fuel flowing well enough to prevent an engine stall.

Schmouddle-WT
05-29-2006, 10:39 AM
Heywooood, I know the mechanism...I just wonder if there is any real pilot flying carburetor engined aircraft willing to comment the topic.

GH_Klingstroem
05-29-2006, 12:23 PM
im a real life commercial pilot and during my training a few years back i once pushed a pa28 really hard and after a few seconds the engine (as you say) will cough a little, but not more!

I also agree that to make an engine quit will require pretty severe windshear not just turbulence! I have very little experience with the I16 in the game but my conclusion is that the engine should not quit on you in turbulence!
In that case, many piston trainers would never make it back on from X-coutry flights on turbulent days!

WWMaxGunz
05-29-2006, 12:41 PM
These modern engine planes do not have equivalent of Schilling disk or anything?

p1ngu666
05-29-2006, 01:45 PM
i think they lose running if htey drop below +1g or something dodgy ingame.

irl this cant have been such a issue because that was what nearly every engine used at the time..

mazexx
05-29-2006, 02:46 PM
Many years ago I learned to fly powered aircraft in a Slingsby T61... If you when't just a bit negative the engine would splutter and cough like an old bum sleeping under a bridge. I really tried to get it to stop once while flying with a friend that was up in a small aircraft for the first time. We where "skimming" the top side of some cumulus clouds and after passing the top of one I pushed to "follow the slope downwards". As the engine almost stopped coughing I screamed to my friend that the enginge is dying! For some reason he didn't think it was fun... I was young... Anyway, I was not able to get it to stop completely. The engine in the T61 is as far from a WWII warbird you can get accept the fact that they where used to teach RAF pilots the first basics of flying. Many fighter pilots have made their first solos in T61's...

Image of a T61 like the one I used to fly (http://www.airliners.net/open.file?id=0812941&WxsIERv=Fyvatfol%20G61S%20Iragher%20G2&Wm=0&WdsYXMg=Hagvgyrq%20%28G61%20Tebhc%29&QtODMg=Cbcunz%20%28RTUC%29&ERDLTkt=HX%20-%20Ratynaq&ktODMp=Ncevy%202%2C%202005&BP=0&WNEb25u=GM%20Nivngvba&xsIERvdWdsY=T-OHQP&MgTUQtODMgKE=Cebonoyl%20gur%20ybjrfg%20cbjrerq%20J neoveq%20ba%20n.arg%21%20Sbezreyl%20hfrq%20ol%20gu r%20Eblny%20Nve%20Sbepr%27f%20Nve%20Pnqrgf%20sbe%2 0genvavat%2C%20guvf%20zbgbevfrq%20tyvqre%20pregnva yl%20ybbxf%20ryrtnag%20naq%20rfcrpvnyyl%20avpr%20g b%20frr%20ure%20fgvyy%20pneelvat%20ure%20ENS%20pby bhef%20abj%20va%20cevingr%20unaqf.&YXMgTUQtODMgKERD=442&NEb25uZWxs=2005-04-08%2013%3A32%3A23&ODJ9dvCE=MN652&O89Dcjdg=1971&static=yes&width=1200&height=812&sok=JURER%20%20%28nvepensg_trarevp%20%3D%20%27Fyva tfol%20G-61%27%29%20%20BEQRE%20OL%20cubgb_vq%20QRFP&photo_nr=6&prev_id=0835774&next_id=0771344) As the text says, "Probably the lowest powered Warbird on a.net!"

/Mazex

WWMaxGunz
05-29-2006, 06:17 PM
WWII bomber crewman I knew first soloed in a T-6 Texan, that's what the states used.
Got a plastic model kit of it somewhere....

WTE_Galway
05-29-2006, 09:37 PM
Originally posted by WWMaxGunz:
These modern engine planes do not have equivalent of Schilling disk or anything?

The shilling disk in the merlins was to prevent flooding under negative G.

It wouldnt work in an engine prone to starvation.

Ruderdyne
06-06-2006, 09:04 PM
'Mouddle,

I have done zero-g pushovers in several different carbureted aircraft. Some will start to quit almost immediately, some won't even miss a beat. However, I personally have never had an airplane even cough in the momentary zero to negative-g loads of even moderate or heavy turbulence or chop. A mountain wave or clear air turb could cause a zero to negative load of a duration necessary to result in fuel starvation, but it isn't very common, and I agree with you, normal turbulence wouldn't do this, unless there is something quirky about the airplane you are flying.

Cheers,
Ruder

Frantish
06-06-2006, 10:18 PM
Originally posted by mazexx:
Many years ago I learned to fly powered aircraft in a Slingsby T61... If you when't just a bit negative the engine would splutter and cough like an old bum sleeping under a bridge. I really tried to get it to stop once while flying with a friend that was up in a small aircraft for the first time. We where "skimming" the top side of some cumulus clouds and after passing the top of one I pushed to "follow the slope downwards". As the engine almost stopped coughing I screamed to my friend that the enginge is dying! For some reason he didn't think it was fun... I was young... Anyway, I was not able to get it to stop completely. The engine in the T61 is as far from a WWII warbird you can get accept the fact that they where used to teach RAF pilots the first basics of flying. Many fighter pilots have made their first solos in T61's...
Image of a T61 like the one I used to fly[/URL] As the text says, "Probably the lowest powered Warbird on a.net!"
/Mazex

OMG!! A Powered glider!!

I pushed my Cessna 152 into a Zero-G push-over (like NASA does). The engine immediately lost power, but did not quit. It took a lot of effort and time to make it happen, something that turbulence will not do, unless you are in a tornado, hurricane or a super violent storm!

This is what I flew http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif
http://www.cessna150-152.com/serialplanes/15281872.jpg
http://71.148.0.203/cessna/reg/FMPro?-db=web_serial.fp3...RecID=12627022&-Find (http://71.148.0.203/cessna/reg/FMPro?-db=web_serial.fp3&-lay=Main&-format=photo_detail.htm&-error=photoerror.htm&-RecID=12627022&-Find)

SeaFireLIV
06-07-2006, 07:26 PM
What the hell?

You guys are comparing pretty modern safe aircraft to an antiquated WWII plane made in soviet Russia, the I16?

Come on guys, just cos you`ve been in a plane doesn`t mean you know how an I16 would act in bad weather.

BTW, I fly the I16 plenty of times in bad weather and never lose the engine anymore, cos I learned how to fly her right (virtually of course).

Sillius_Sodus
06-08-2006, 04:43 PM
Years ago I was taking off in a DHC-2 Beaver on floats from a river and hit a strong updraft immediately followed by a down draft at about 100ft AGL. It lasted less than a second but the engine did quit and didn't start up again until I was beginning to flare for landing in some rapids big enough to write off the floats. Made it back to the dock and took the rest of the day off.

Actually, it was my last trip of the day.

Good Hunting,
Sillius_Sodus

joeap
06-08-2006, 04:50 PM
Originally posted by Sillius_Sodus:
Years ago I was taking off in a DHC-2 Beaver on floats from a river and hit a strong updraft immediately followed by a down draft at about 100ft AGL. It lasted less than a second but the engine did quit and didn't start up again until I was beginning to flare for landing in some rapids big enough to write off the floats. Made it back to the dock and took the rest of the day off.

Actually, it was my last trip of the day.

Good Hunting,
Sillius_Sodus

Proof positive. http://forums.ubi.com/images/smilies/metal.gif

PBNA-Boosher
06-11-2006, 09:32 AM
I doubt I could compare experience in a PA 28-140 to an I-16, but I once got hit by a nasty wind current. I got a lot of sputtering, but the engine didn't quit. What did quit was the alternator. So I flew home without electrical power. No radios, no fuel gauges, most of my engine gauges gone, etc... Of course, the engine's still running so the plane is fine, but hey, I was a new pilot at the time.