rel4y

Ok one last statement on ratings. 1.45 ata is the german military power, same as 61" for the Mustang. MW50 was introduced as an alternative to the early 44 short in supply C3 fuel. It was chosen because water and methanol are crap easy to produce/ mix and no shortage was ever to be expected. You could fill it up with 30/70 mix or wathever you had the joy of mixing at the time. You are saying there probably were shortages in supply and it is likely aircraft flew at lower ata etc. This is pure speculation and no data indicates anything like it. So far you have argued reasonably, but this sounds like desperate try of legitimation to me. Once again 1.45 is no official rating but simply military power. All production line engine charts available clearly rate the DB605DB/DC for at least 1.8 ata. One could argue well there were probably supply shortages in spark plugs for the allies because heavy lead fouling caused the need of replacement about every two missions. So maybe some Mustangs were knocking heavily on WEP and could only run at military power which should make 61" boost an engine rating. See what I am doing? I already said testing how the 67" Pony fares against a 1.45 ata military power only 109 is for game balance a valid choice at sea level. Higher up the disparity will be gigantic because the 109 supercharger cant keep up the charge pressure for reasonable engine output. So what we are doing is completely ahistorical but in favor of frustrated P-51 simmers to keep the motivation alive. This is a reasonable thing to do. I repeat once more 1.45 ata is not and never was a WEP engine rating for the DB 605DB/DC, it is normal military power. There were only two engine ratings ever issued, 1.8 ata and 1.98 ata. Btw Ethanol works just as well, so if you found a supply of wodka at the eastern front you could fill the MW tank with it and fly 1.8 Ata or pinch a hole in the pipe and get drunk in flight.

Has this been reported? It most likely caused a game crash after all.

Oh well, maybe you are right maybe not. Ill leave it to ED to decide. I really dislike the whole fuel thing. :puke: Could anybody check if you can fly through your own ordnance just dropped in the P-51/ Dora? Theres is bug in the 109.

Yeah in a beautiful Spitfire with completely different cooling system and supply chain. One is RAF and the other one USAAF. Both had their own leadership and own regulations. Notice a difference? : ) And yes, I am OK with it. Cant speak for anybody else.

44-1 is 150 grade fuel. I am OK with 130 grade 72". The motor/blower needed adjustment for 44-1.

You keep saying mid/high rating, why? If you dont consider 1.98 Ata was being used (which I may even understand since it was authorized only for roughly 1.5 months before ve day), then there is only one rating, namely 1.8 Ata. If you believe the OKL document excerpts I posted (1.98 authorization in March 45) then it is the lower/lowest rating of the two. Otherwise please show data of a K-4 production line variant with rating below 1.8 Ata and I will stand corrected. PS: Remember, MW50 injection system and tank were production line installations for the K-4.

Hey ironjockel! The mission editor has a bug at the moment. You can't change MW50 in single player missions as well. I would assume this is related.

Another bug I found today was that you could fly through your own bombs which you just dropped. Once the bomb was even rendered in my cockpit as I passed through it. It seems to depend on which detonator mode you use. Another time the bomb was suddenly accelerated a few 100m to my rear and after a few seconds my aircraft exploded. I will add a few tracks to show what happened, they replay correctly for me. Last time I tried my game crashed and I will add the corresponding log files.

When going above 1.45 ata without MW50 activated the 109 trails grey/brown smoke and the engine starts knocking/overheating. Now there was a bug in an earlier version where the smoke would come up even when MW50 was used and wouldnt dissipate. Now the smoke still doesnt dissipate for as long as you fly with boost above 1.45 ata and only when going below that the whole length of the smoke trail will vanish in 2 seconds. This is independent of how long the smoke trail is. So the smoke trail is clearly still bugged. Can you guys reproduce that? PS: How do I drop the droptank? I cant get it to drop.. I thought it would act like ordnance? Nevermind, its the ordnance emergency release and wasnt mapped on the keyboard! :thumbup:

I just tested a bit. When engaging 1.8 Ata without MW50 the engine will break after 12-85 seconds. So if MW50 is not available please say so somewhere, because people will frequently break their engines when moving the throttle above 1.45 Ata!

What people just dont seem to realize is, that however much you increase boost for the P-51.. at sea level the 109 will rape the Mustang! And people wishing for a G-10 or G-14 dont understand the problem at all. A G-14 may even outperform a K-4 at deck due to its engine design and less weight. A G-10 has exactly the same engine as the K-4 but is lighter, a bit drag-ier and has the better anti fighter armament (20mm MG151). The Mustang will however fly cirlces around a 109 at high altitude due to lower wingloading and blower design. So the only viable choice is actually to increase the altitude of the fight. The P-51 was designed as a high altitude escort and not a low level crazy dogfighter. But for some reason people dont want to hear that. :noexpression: At 21000 ft the 67" (actually the data is for 61", R.D.E.1.(a) 1/9/44) Pony has ~ 1400 BHP while the B4 + MW50 109 only has ~1280 BHP. This discrepancy should increase with altitude.

You need to differentiate between B4 and C3 fuel. You mixed the engine output between the low octane (87) B4 fuel and the high octane (96/145) C3 fuel. The ground crew could adjust for different compression between the two fuels by simply turning a few screws. MW50 is made up of 50% water and 50% methanol and is used for charge cooling. The water in MW50 is used to cool the air in the supercharger, therefore making it more dense and throwing more oxygen molecules in the engine to react with hydrocarbons and producing greater mean effective pressure. The methanol has actually less cooling effect than the water, but is used in conjunction to limit knocking of the engine and increases the heating value. The whole MW is pressurized and supercharger injection is executed at a few bar overpressure. Beyond full throttle height MW50 does not deliver much additional engine output, only a few percent due to charge cooling effect. So you see, when not using MW50 with B4 fuel you will lose some hundreds of BHP below full throttle height. You can run the DB605 at higher boost than 1.45 Ata without MW50, but the engine will start knocking and being overstressed. The engine will not produce the same amount of BHP at the same boost pressure as with the use of MW50. Now with C3 fuel the story looks different. C3 fuel as said before has a lean octane rating of 96, but was of synthetic nature and added with high amounts af aromatic hydrocarbons which gave it a theoretical rich octane rating of 145. This is comparable to the allied 150 fuel type and was in use since 1942. The DB605 should in theory produce a few less BHP (~50) at 1.8 Ata with C3 fuel than with B4 fuel + MW50. This again is due to missing charge cooling effect. It will however not cause knocking of the engine because the octane rating of C3 is much higher compared to B4. Furthermore the effect is altitude independent and not time limited. After corrections in quality control of DB605 parts it was cleared to be used with C3 + MW50, by which another increase in boost pressure and therefore further increase in BHP (2000) engine output was possible. So to conclude: 1.45 Ata, B4 no MW50 -> 1410 BHP (cant really run higher boost or will risk engine blow up) 1.8 Ata, B4 + MW50 -> 1825 BHP (10 minute rating) 1.8 Ata, C3 no MW50 -> 1775 BHP (unlimited) 1.98 Ata, C3 + MW50 ->1973 BHP (10 minute rating) Now a 1.45 Ata limited K-4 is only of theoretical nature, since it employed production line installation of MW50 tank and injection system. As I said after depletion of the MW50 (~40 min) the pilot would be limited to Steig- und Kampfleistung (1.45 Ata) but it is not an official rating. The MW50 tank however could be left empty or filled with normal avgas fuel for extended range, in which case a cockpit switch had to be adjusted.

Well I guess its worth a try. Just set the MW tank to empty instead of B4 fuel. :thumbup: I suspect a lot of engine failures though, since theres no way to limit the boost as in real life. Has anybody tried flying the K-4 for prolongod periods without MW50 at boosts above 1.45? I would expect rapid overheating, throttle firewalling should be a no go. Will test tomorrow.

How much BHP does a +21 lb/sqin / 72 inHG Merlin 66 put out? I found conflicting numbers. Following numbers are for the M.S. blower. at +18 lb/sqin / 67 inHG I have 1700 BHP (1630 BHP at SL?) -> current model at +25 lb/sqin / 81 inHG I have 2000 BHP So at the moment we have a 1700 BHP P-51D vs a 1825 BHP K-4 at ten minute rating. And you want a 1700 BHP P-51D vs a 1411 BHP K-4 to make it fair, did I get that correct?

Alright! :thumbup: You can not run the DB605 with B4 fuel as modeled in the game on 1.8 Ata. The fuel is simply not of high enough octane to eliminate engine knocking. C3 fuel in comparison is similar to allied 150 octane fuel and before change in mixture somewhere along the end of the war was 96/145 octane. (I am really not sure how much the octane rating changed and when that change took place. As I said I am not interested/ knowledgable in fuel discussions.) DB605DB on B4 fuel without MW50 -> Sondernotleistung 1.5 Ata, (very short time, dont know exactly) mostly combat power of 1.45 Ata must be used DB605DB on B4 fuel with MW50 -> Sondernotleistung 1.8 Ata, 10 minute rating DB605DB on C3 fuel no MW50 -> Sondernotleistung 1.8 Ata, no limit in boost time, altitude independend effect DB605DB on C3 fuel with MW50 -> Sondernotleistung 1.98 Ata, 10 minute rating As qouted earlier, the highest rating saw some use after the OKL order dated 20.3.45. If significant or not lies in the eyes of the observer. In March 45 the war was pretty much lost and german forces were surrendering to US/GB troops while fiercly fighting soviet forces. Now please dont misunderstand me. I am not saying it is impossible a K-4 without MW50 met a Mustang. There probably where some planes flying around in this configuration, but there is no specific data that I know of. Once the MW50 tank was empty (used up or leaked) you couldnt use it anyway. But what I am saying a 109K would not meet a 30NA Mustang at any time in history. Also I have said 72"hg should be introduced, maybe even 75. I would need to check sources to make up my mind. Now when I am flying I am using MW50 mostly when going vertical to get an edge over the opponent in climb. In medium speed scissors or turn fighting the high boost torque is your enemy in my opinion. Since Echo was right, the MP calculation is misleading Id like to correct this. HP calculation however is not misleading as prop efficiency is similiar with a slight edge to the 4 blade Hamilton Standard. Only difference is max torque development being mostly negated by RPM adjustment. DB605DB 1.45 Ata -> 1411 BHP (Steig-Kampfleistung, B4 fuel - C3 fuel in 1.98 Ata configuration has actually lower output) 1.8 Ata -> 1825 BHP (Sondernotleistung 10 min rating) 1.98 Ata -> 1973 BHP (Sondernotleistung 10 min rating, C3 fuel only)

I have to disagree with you here. The 1945 P-51D-30NA is very much the best P-51D in existence. People seem to forget all the aerodynamic, weapon & structural improvements which this includes and for some reason only focus on boost pressure. When raising the boost pressure, the DCS P-51 will be pretty much equal in status and equipment to the ones used in Korean theatre in the 1950s. As said before the K-4 modeled is the lowest boost version there was. You could only strip it of MW50, which is not historical but merely an act of game balance. PS: Echo I know I didnt include compression ratio, but I did not want to further complicate this. You are very much right though. The prop effiecency of the P-51 modelled is higher than the german one though. So that is a non issue.

While I completely agree with you on most parts, you mixed something up right there. The DB605DB of the K-4 cannot be flown at 1.8 Ata with B4 fuel without MW50. It would overheat and start knocking like hell. That is due to the missing charge cooling effect of MW50. The maximum boost without MW50 would be 1.5 Ata. C3 fuel by itself would also have a max of 1.8 Ata, with the difference of being altitude independent and as far is I know no time restriction on boost was issued. Just to make it more obvious what you guys are wanting: 67 inHG = 2.24 Ata 72 inHG = 2.41 Ata 75 inHG = 2.51 Ata 1.5 Ata = 44.88 inHG 1.8 Ata = 53.86 inHG 1.98 Ata = 59.24 inHG I have written in a different thread about the role of the P-51 in combat. After it was used in air supremacy fighter sweeps many german planes were destroyed on the ground and right before landing/ after take off. The wings were ordered to attack everything they could find, this happened mostly low level. Most Me 262 combat losses were results of this scenario, so it proved to be a highly effective strategy. Whole allied fighter wings were vulching known Me 262 bases, that is why these were equipped with FW190 "Platzschutz Staffeln" which should protect the jets in their vulnerable phases. But allies were vulching all Luftwaffe bases whichever aircraft was stationed there. So indeed P-51 should attack ground targets and columns everywhere and anytime, cause that was what they were ordered to do. What we really need is a AI B-17 or any other allied 4 mot Bomber with well modeled air gunners. At defending high altitude interceptions the P-51 would shine and quickly servers would be flooded with Mustangs.

I am actually very much a spitfire guy and respect people with valid arguments. I'm by no means a P-51 expert, but I feel confident in an argument with you. Do you know what a Reynolds number is? Concerning MW50 please look at 1942 BMW801D tests. Even NASA states laminar flow was not achievable by the P-51.. why do you think the idea of laminar flow was quickly abandoned after WW2 and instead the German methods of calculating boundary layer transition were adopted. Prof. Hermann Schlichting et al tested the Mustang wing at high Reynolds numbers and found laminar flow to be non-existent even in windtunnel tests. The new generation Me 262 wing had superior characteristic and was non laminar flow. The German engineer Edgar Schmued however did a wonderful job at designing the iconic P-51. Once a quality British engine was put in it was a highly potent plane. Also manufacturing quality was superior to the German late war production, which made the piftyone an excellent fast escort. It could however not leave dogfights at will. Where did you get that from, history channel? To stay on topic: please put in ground targets and supply columns. That would make it more interestingin my view.

Sorry Solty, it is absulutely not worth it to disprove you everytime.. Last time I did that you argued with Wikipedia data and lost on all fronts. Get your facts straight first, what you just said is wrong on so many levels..

As I said when putting in context that we have a P-51D-30NA. Surely not in 44. :thumbup: OKL, Lw.-Führüngstab, Nr. 937/45 gKdos. 20.03.45 10. I. / JG 27 Bf 109 K-4 no change boost increase to 1.98 ata 12. III. / JG 27 Bf 109 G-10 no change boost increase to 1.98 ata 19. III. / JG 53 Bf 109 K-4 no change boost increase to 1.98 ata 20. IV. / JG 53 Bf 109 K-4 no change boost increase to 1.98 ata Strength numbers 9th April 1945. I./JG 27 29 III./JG 27 19 III./JG 53 40 IV./JG 53 54 Total 142. 1.8 Ata C3 fuel use by K-4 can be proven by pictures alone, since many photos show aircraft with a C3 triangle. But there are certainly OKL orders somewhere. I dont particularly enjoy the whole fuel discussion a lot.

Arent these the ones which are in the EN/Single folder? :huh:

Well the 109 is literally a ton lighter than the pifty1 and by the way flying on its historically lowest rating. C3 fuel, 1.98 Ata C3+MW being historical possible higher ratings. Taking into context that the P-51 modeled is a July/August 1945 Iwo Jima model with HVAR rockets which were never used in Europe by P-51s, there is no reason to complain. In the ETO the early type 3 rocket christmas tree launchers instead were employed. A K-4 without MW boost is simply ahistorical, as germans were using it since as early as 1942. By early 1944 pretty much all active duty fighters were fitted with MW50 boost. Even 75 hg will not change climbrate and acceleration significantly. People are expecting way to much off a high altitude escort at deck. Having said that, I think 72 hg boost is historically perfectly viable (maybe even 75 hg, I would need to check sources) and should be introduced. It will however not change a thing in dogfights around the 400-450 kph range. At high altitude the pony is a beast, try taking the fight to 9-10km altitude and you will fly circles around 109s. By the way mid 1945 historically speaking the Dora should be flying on C3 fuel as well. The pony has a turn, acceleration advantage though since the laminar flow drag bucket is modelled, even though even recent NASA papers conclude laminar flow did not exist in the pony in any other than lab conditions. Rivets, bumps, even dead flies would completely disrupt the laminar airflow. These small imperfections also dissipate energy like its a sport. In the areas of the prop slip stream laminar flow is a joke by itself. The aerodynamic forces will ripple,dent & warp the wing structure in suttle ways making airflow turbulent. At real flight Reynolds (>20.000.000) numbers the effect would disappear even under lab condition. There are many reasons laminar flow is a myth and the 51 was underperforming compared to charts. For this reason I am also very sceptical about dubious excel calculations extrapolated on test flights with coated and sanded wings, which were conducted using paper sheets to protect the wings from insects during start/ low level flight. I even have a picture here of this interesting method. Conclusion: Wait for a real allied dogfighter - the Spitfire. I will be flying nothing else for a while after release.

They are still there and have been there for as long as I can remember. Select Mission, Flaming Cliffs, click on the little folder symbol and chose the Folder EN. There you go! :smilewink:

If you slightly open rads though, you can go nowhere near as fast. German level speed tests were (mostly) done with rads 3/4 closed. When doing that I cant reach 580 kph, so jet thrust from the rads must be contributing quite a lot. I cant imagine that the radiator drag per se would decrease a lot when closing the rad flaps by ~5cm. At least not from almost closed to fully closed. To be clear, I still think everything is perfectly fine. I am merely thinking out loud. :book: I am probably opening the rads more than how it was done in WW2 tests.

Sry that was ground speed.. :doh: I messed up. OMG, I never knew that you could switch to TAS! That is so awesome! I have to retest speed at FTH now!:joystick: Yeah thats true, pitot instrument error, altitude, air density and temperature play a role there. I always test level speed without weather effects under normal conditions. 1013 mbar, 15 °C that should be how engineers in WW2 were testing as well. Still the pitot error would remain and I guess DCS is very much capable of modeling this! :pilotfly:So you are probably right!