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View Full Version : What am I doing wrong to toast my K4 engine?



HayateKid
04-15-2004, 08:55 AM
I have prop pitch on auto, radiator fully open, turn on MW50 on the ground before I takeoff (either when engine is still off or low idle) and leave it on.

In flight I make sure not to hold throttle above 100% for too long. When overheat warning comes on I slide it back to the 90s. Still, I end up frying my engine. Last night, the engine exhibited loss of power without even going into overheat. And I haven't been flying long enough to run out of MW50.

What am I doing wrong?

"First learn stand, then learn fly. Nature rule, Daniel San, not mine." - Mr. Miyagi

HayateKid
04-15-2004, 08:55 AM
I have prop pitch on auto, radiator fully open, turn on MW50 on the ground before I takeoff (either when engine is still off or low idle) and leave it on.

In flight I make sure not to hold throttle above 100% for too long. When overheat warning comes on I slide it back to the 90s. Still, I end up frying my engine. Last night, the engine exhibited loss of power without even going into overheat. And I haven't been flying long enough to run out of MW50.

What am I doing wrong?

"First learn stand, then learn fly. Nature rule, Daniel San, not mine." - Mr. Miyagi

Snow_Wolf_
04-15-2004, 08:59 AM
You should not engage that MW50 stuff untill you reach the alt of 6000m (Just don't turn on the MW 50 stuff and u should be fine)

http://aa.1asphost.com/seafury/Mononoke%20Hime/hime.jpg

Snow_Wolf_
04-15-2004, 09:09 AM
History
The essential idea was developed in the first decade of this century. The original purpose was cooling. By 1910 some engines which had been water-cooled were simply produced without water-jackets after addition of 'internal cooling', as water-injection was first called. Those engines had compression ratios around 4:1 and the phenomenon of preignition (knocking, pinking) was unknown. Later however this became the main reason for water injection which turns out to give spectacular octane improvement, allowing CR as high as 13:1. By the end of World War II many aero engines used water-injection. German versions used water-methanol mixtures, partly because straight water would freeze in winter. The Wright Cyclone, a main U.S. aero engine, tested with water and methanol-water (the two liquids being miscible in all proportions, unlike methanol & petrol), showed 50:50 best (as had the Germans). The results were summarised as ‚£quot;high savings in fuel cost - 52% at 100% power, decreasing to 25% at low cruise powers... pure water is approximately equal to fuel when used as an engine internal coolant at high power". Water gained the Corsair (flown by some Kiwi pilots in the Pacific) 350 bhp on its normal maximum of 2100 bhp - a 17% increase. These were supercharged engines, so the results may not translate readily to normal aspiration. Another alcohol, infamous ethanol, was similarly mixed with water before injection, but was not as good.
When Renault attacked Formula 1 with twin turbos cramming several atmospheres of boost into Gordini's 1500 cc V6, they readily achieved 450 bhp but burned holes in pistons. Then a Kiwi mechanic recalled water-injection; a reliable 550 bhp won the championship. The Saab turbo works rally car at one period had a water tank as big as the petrol tank. Some modern gas-turbine aero engines use water-injection for maximum power at takeoff. Various naval and rail external-combustion rigs are improved by steam injection.


http://aa.1asphost.com/seafury/Mononoke%20Hime/hime.jpg

Leif_Eriksson
04-15-2004, 09:40 AM
But where are those wicked oxygen boost gadgets used in the first "Mad Max" film from the eighties http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif

mortoma
04-15-2004, 09:52 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Snow_Wolf_:
You should not engage that MW50 stuff untill you reach the alt of 6000m (Just don't turn on the MW 50 stuff and u should be fine)

http://aa.1asphost.com/seafury/Mononoke%20Hime/hime.jpg <HR></BLOCKQUOTE>Theres no altitude limit on MW-50, you are thinking of GM-1. German's have 3 different types of boost. MW-50, GM-1 and Erhote Notliestung, although I may have spelled that last one wrongly. The only one with altitude restriction is GM-1. I simply wait until just before an engagement, then throttle back to idle and turn on MW-50, at any altitude, never have a problem.

GK.
04-15-2004, 09:57 AM
its a bug in the programming. i think the issue was raised in olegs ready room but will probably be ignored. MW50 could be run and throttle at 110% for 10minutes before overheat and a little longer before engine damage. The germans were expert engineers and had rugged planes/engines. this is a glaring inconsistency in the modeling.

http://data.photodump.com/gk/tonysig.jpg

JG53Frankyboy
04-15-2004, 10:06 AM
the total time that MW50 is available seems a LOT reduced since AEP (as always no flightmanual is talking aboutthat http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif ).
and if you run it if its empty, your engine is very fast dead. but there seems no sign at all that is telling you "hey, disable MW50 - its empty !"
personnaly im enablying now the MW50 not before im reaching the combat sector.

Maple_Tiger
04-15-2004, 02:34 PM
I sometime find that when im in the FW190A9 and the BF109g/6 that the engine dies on me also. But i never see an over heat lol. http://ubbxforums.ubi.com/infopop/emoticons/icon_frown.gif

Capt. 361stMapleTiger.
http://www.imagestation.com/picture/sraid111/p8129c76875e610629059ca5b8101514f/f90e96ec.jpg
Proud member of the FBAA and Nutty Philosohpy Club.

Kurfurst__
04-15-2004, 04:00 PM
I was in email contact with Oleg, and could convince him to change the model. He said it will be changed so that engines won`t be damaged at least until 10 mins at WEP (as in historical manual). Hope this will be actually present in the final patch, and not forgotten about...

As for MW 50 operation, I think the only limit you should keep is not turning it on/off when the the throttle is above 100%... as historically this would turn the boost upside down, leading to preignition and knocking w/o the water injection present to help boost issues.

There`s no altitude limitations with MW50. In real life, system was automatically stopped w/o need from input of pilot when the altitude was high enough so that there would no gain from it, ie. to save engine wear from corrosion. MW switch was more like enable/disable, rather than turn on/off..Historically it was automatic, when pilot pushed the throtlle beyond 100% power or 1.45ata boost, the system started to inject MW50 into the eye of supercharger, and opened the butterfly to provide 1.98ata pressure and vica versa. Practically, the amount of MW was enough without time restriction, ie. fuel capacity would be very low from maximum fuel consumption under max power, less than 100 liters remaining from full if MW was used constantly..

So basically the only real limitations were : no more than 10 minutes at a time, and/or max. engine temperatures to be followed.

http://www.x-plane.org/users/isegrim/fat-furred%20tigerB.jpg

"We've got the finest tanks in the world. We just love to see the German Royal Tiger come up on the field".
- Lt. Gen. George S. Patton, Jr. Febuary 1945.

"One day a Tiger Royal got within 150 yards of my tanks and knocked me out. Five of our tanks opened up on him at ranges of 200 to 600 yards and got 5 or 6 hits on the front of the Tiger. They all just glanced off and the Tiger backed off and got away. If we had a tank like that Tiger, we would all be home today."
- Sgt. Clyde D. Brunson, US Army, Tank Commander, February 1945

Maple_Tiger
04-15-2004, 05:38 PM
Now that is good news. Atleast when we get the patch i won't have to worry about killing my engine when using MW 50.

Capt. 361stMapleTiger.
http://img52.photobucket.com/albums/v158/Maple_Tiger/pentagoncropcircle.jpg
Proud member of the FBAA and Nutty Philosohpy Club.

Fennec_P
04-15-2004, 07:50 PM
Sweet.

But wasn't that only for the FW-190D9 with MW50?

I remember reading that MW50 on the Bf-109 was intended for use of no more than 2-3 minutes at a time, unlike the 10 minute limit for FW-190D9.

Franzen
04-15-2004, 08:20 PM
I use the MW50 before my wheels even turn. I never cook my engine. Since I can never tell whether to go left or right on the runway(we play full real) I need to take off in a short distance most of the time. I never turn off the MW50 until I'm headed back to base. Either you have a bad bug or I have a good one. To be honest with you I never gave this any thought since it has never been a problem.
Of course my engine does overheat but I drop the throttle and dive a little. It cools it down quickly.

Fritz Franzen

Fennec_P
04-15-2004, 09:32 PM
If its the same as FB, currently you can run 110%+MW50 for about 3 minutes before breakdown, and 105%+MW50 for just over 5 minutes.

This is in level flight at 1000m, rad closed, from a continuous cruise at 100% power.

If you do it right from takeoff it lasts a longer time, because the engine is cool to start with.

http://members.shaw.ca/fennec/flakw.jpg

HayateKid
04-16-2004, 09:38 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Maple_Tiger:
I sometime find that when im in the FW190A9 and the BF109g/6 that the engine dies on me also. But i never see an over heat lol. http://ubbxforums.ubi.com/infopop/emoticons/icon_frown.gif
<HR></BLOCKQUOTE>

Exactly. Only i've seen this happen in the K4.

"First learn stand, then learn fly. Nature rule, Daniel San, not mine." - Mr. Miyagi