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ZachariasX

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About ZachariasX

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  1. The problem is how windows didtributes processs among the cores. For flightsim, you‘d actually need to have a know, most overclockable core reserved to its main „fibre“ thread, while carefully distributing the other tasks among the cores. Windows is so bad at this that noone in high preformance computing woukd touch windows even with a stick. Don‘t count on such software. Rememer „Ram Doubler“?
  2. ZachariasX

    Me 262 Questions

    You‘d be the only one to think so at that time.
  3. ZachariasX

    G14 vs MK9

    The better climb of the G14 is very marginal and for practical purposes will not save you. You auickly reach altitudes (and your quarry as well) where the Spits gets more than competitive. The IX at max rev. and throttle will always be able to follow. You can practise that on Berloga pretty well, good 109 riders will be keen on doing high yoyos on you, but engaging a slow Spit at high speeds. This trick requires significant higher energy when opening the fight. Then you may distance yourself in the vertical after the first pass. NEVER turn with the Spit, unless the Spit it flown such that you may have good reason assuming you‘ll have the edge on him anyway, be it by damage or just bad piloting. If you are caught by a Spit, especially by the IX, in my experience you can try rolling scissors while slowing down. In the 109 you have the edge in pulling high AoA and get your bearings on him. The Spit doesn‘t like to be flown such. In the Spit I never follow the 109 in such a maneuver, I just try a snapshot begore passing him at higher speeds and then make something out of my higher energy.
  4. ZachariasX

    Pfalz D.IIIa and Sopwith Camel

    This should be a function of the Ju-52 for leaning mixture at altitude.
  5. ZachariasX

    Realism of zoom

    Just don‘t tell him you can do the same on pan view using ministicks on the HOTAS!
  6. ZachariasX

    Compression Ratio and Octane

    That‘s for you to type up why this is an interesting metric for determining what the engine can do.
  7. ZachariasX

    Compression Ratio and Octane

    I'm mean here and I say, they stand with the French, as they made a living on the Hispano Suiza that was turned into a Klimov. But these are also larger displacement engines, the Klimov 105 is still a Hisso in some way. Both are relatively large ~36L displacement and similar compression something of 7:1. The Klimov has a slightly better power to weight ratio (1.42 to 1.32 kW/kg) probably due to a better supercharger mainly. It is actually close to the DB601 with similar power output at 34L displacement. The cylinder compression of 6.9:1 is marginally lower than the Klimovs 7.1:1, but essentially it is the same. The Daimler however has a 1.47 kW/kg power to weight, showing what you can do with a neat supercharger, even though it is single stage. Lets have a look at the Merlin. It has a very low 6:1 cylinder compression. It is the same as in the Peregrine or the Kestrel, the baby V12's. But if you are about to add a big blower to the engine, you don't have to go all too high with compression in the cylinder. At 2 ata, you'll have 12 ata in the cylinder insetad of 6. It can be said that all Klimov, Hisso and DB tried to get more out of the piston engine itself, whether RR readily relied on the supercharger. That the super(turbo)charger is the way to go is especially obvious as you can see it in todays cars. There are hardly any naturally aspirated engines anymore. Those that are have compression (since the 1960's) ratios up to around 11:1, basically mimiking what the Merlin is capable of doing at +16 boost or so. Both Klimov and DB are simply not made for the same turbo installations and hence can't be compared in absolute boost values. The DB needs less boost for the same power. But it comes at the price of being essentially a heavy engine for a light aircraft (in case of fighter AC). American engines running at ~6.5:1 compression were a bit of an intermediate. After all, they were fond of turbosuperchargers and were thinking in that direction as well. But as that was mainly envisaged for altitude performance, you could give the engine a tad more compression than RR boffins would do. In this sense, if you have low compression in the piston of a 27 litre engine and you know you can add twice the air in the cylinder before presure gets critical, you have built essentially a 54 litre engine. Th Merlin is a tiny big engine and for good reason is a great choice for racers. If you are not convinced that you can fetch that much air at low temperatures, you better increase piston pressure such that with the added air it will reach no more than 13:1 or so. This shows how borderline both +25 boost and 1.8 ata in fact are for those engines. TL;DR It's just Cyril Lowesey's superchargers on one side, and then the whole rest of the world on the other side.
  8. ZachariasX

    Pfalz D.IIIa and Sopwith Camel

    Oh, absolutely.
  9. ZachariasX

    Me 262 Questions

    Doubtful.
  10. ZachariasX

    Tempest Mark V research

    Around Christmas/New Year, I shouldn't think ratings above +11 boost were issued. But From February to Summer, I'd expect a gradual increase of permitted boost ratings.
  11. ZachariasX

    Pfalz D.IIIa and Sopwith Camel

    They differed in wing loading. That's about it. The Pup could go up to 6'500 m altitude (provided both Pup and pilot were in shape), whereas wing loading of the Albatros didn't permit this altitude, lest fyling a turn at this altitude. Performance degradation is about equal in both rotary or inline engine. The Pups were like little balloons 500 meters above the Albatri, trying to dive on them and then trying to climb up again. If they had a free rotating machine gun on the Albatros they could have "popped" one Pup after the other. below 5'500 meters Any Abatros drive could have massacred any Pup at leisure.
  12. ZachariasX

    Compression Ratio and Octane

    @NZTyphoon Good links, thank you. maybe I shold also add this one, from Shell some facts and the about the future of AVGAS. One minor correction, high performance fuels tend to burn slower than antique fuels. The slow burn makes combustion more controllable, greatly aiding in achieving high power ratings as well as efficient engines. Nowadays you can also inject in only part of the chamber, using a fraction of fuel, mixing obnly with a fraction of the air in a specific location, while giving an efficient burn. You couldn't do that if you don't have tight control over the burn. It is also of note that slow burn, as we have it for the "good fuels", is not always desirable. Ancient engine concepts like the Monosoupape rotary engine in fact relied on a fast burn, as they ejected the combustion gases in the same stroke when the burn is taking place. This means, for "efficient" operation of these rotaries, combustion has to be completed way before the piston travelled all the way downwards. In the lower quarter of the stroke, the valve opens and lets the pressure out and if you have residual burn then, ll you get for that is a little fire next to the engine instead of power cranking the prop. This way, you actually have a design that relies on the low octane, fast burning turd to operate efficiently. Also, think of high performance engines as EFFICIENT engines. I remember (lacking any source though) the chief technitian of VW saying that, after being asked why VW would develop something like a W16 engine for a Bugatti, he said that only engines that have the economy can be good racing engines. Fuel quality is key to that. Think of the engine and the fuel as a combination of technology. Fuel is made. Engines are made. They should match to give you that extra power.
  13. ZachariasX

    Tempest Mark V research

    No, it is exactly as you said. However, you also have 15 boost in the same timeframe, making actual use (as stated in pilot accounts) very plausible.
  14. ZachariasX

    Compression Ratio and Octane

    Maybe one more thing, just to illustrate how fuel quality and engine devoelopment is interlinked. Back in the prehistoric times, when short, chunky pilots as these were defining flight they also preferentally flew aircraft that consisted of engines with some controls and some wings attached to it. Planes looked like this: or, if for some weird reason flotation was an issue, like this: Or if they felt like having a good time, it looked like this: Making combat aircraft from that gave in worst case this: A plane "as deadly as it looks". Best case, we get the Me-109 or the Spitfire. Still "engines made flyable", and somebody even brought a gun to put on them. Now some poeple were wondering why Douhet come up with the doctrine of "the bomber always getting through", but I guiess these planes are part of the answer. What these aircraft have in common, is that they are very small (as small as possible) and they are very light. Being overpowered, you used two main modes, either full bore (racing, intercepting, impressing your neighbors) OR you used them at rather low throttle settings that still would make them fly comfortably well. Now, what is the connection to fuel quality and engine design? Remember, above, I said that "bad fuel" costs you mileage, as you have to put in more to suppress knocking and cooling the burn, cooling your cylinders in consequence. BUT, if I let the very same engine run at lower power outputs, I can lean the mixture, making the burn more efficient, hence increasing your mileage. Now we come to bottom of the issue. The higher I push an engine on given fuel, the lower its efficiency. There is a thing called cruise speed. Cruise speed is a speed at which you cruise somewhere, making your mileage a metric of paramout importance. And this is why at cruise speed you lean your mixture. After what I've written above, the point where you had to enrich the mixture for going faster is a limit to efficient cruise. Now, this delta, from max. cruise speed to max. speed (max cruise power to max. power) is largely dependent on your fuel quality, as "bad fuel" will lower that point, even though you might get the same cruise speed. Both the Spit and the 109 started out with rather smallisch V12 engines of about 27 litres, meaning that the limit of efficient power output is very low compared to possible max power outputs, and it will also be very hard to up that efficient power output unless you increase fuel quality in terms of burn efficiency. The result is (besides abyssmal range) the low cruise speeds of both the Spitfire and the 109. If you fly faster, your engine will be progressively less efficient. In the Spitfire, at least there they found some empty space for more gasoline to offset higher boost ratings. The 109 on the other hand was greatly helped by the fact that work came to him, instead of him having to fly all the way to work. Starting out with 27 litre engine, at roughly 1000 hp, what do you do when you want more power. K said correctly that people hate to make new engine blocks, as that cost money and tends to delay production. So what did Rolls Royce do? They were working on blowers to pump more air through the same block. This works well IF you have fuel good enough that doesn't force a rich-rich mixture early on, negating any hope for range in combat. Because they had a fuel that had to be set on a rich mixture later, they could do so. The octane ratoing only set them a cap about the maximum boost rating. And this was always in a region, where the engine stared to come apart and the progresively had to reinforce the engines to follow possible boost ratings. The Germans were not so lucky. At DB, they knew that with their synthetic fuel, they soon had an engine that got them nowhere, literally. So they had to come up with an alternative. They actually had to "split" the use of their engines between running like mad and getting somewhere. That required two fuels, one that got you somewhere (B4) and one that didn't get you shot down right away (C3). In consequence, they were compelled to build engines that accepted both low and high octane ratings and make the most of it. And for the B4, that compelled them to up displacement right away. And they did so. The DB60X series progressively went from 26 to 44 litres in just a couple of years. And you understand now why even the most fancy "big block" of those must accept B4 fuel. As well as C3, of course. Rolls Royce on the other hand the pumped up that little engine like there's no tomorrow, up to +25 boost. Amazing. BUT with what I've said above, while the engine was about to produce 2000 hp instead of 1000 hp, the point of where it lost efficiency remained the same. Even the Spit IXe on steroids had an abyssmal cruse speed. Tempest pilots were mocking them as themselves having a higher landing speed than a Spitfire had a cruise speed. To make matters worse, the slower you fly at give fuel consumption, the shorter your legs are. It's not just that the Spit didn't have much fuel abouard, it also could not make much from it as it was slow. It took some work, like removing weapons and lightening the airframe to give it faster an longer legs in the PR versions. The Germans on the other could make C3 or B4 fuel, as they liked. But making one came eat the cost of making the other. It's not that they had one and were working on the other and "kept the bad one as extra". And where was B4 mainly used? Bombers, recon, transport, all of which actually needed to go somewhere. It's not that they wouldn't have fancied to get 100 extra hp on the He111, not at all. It's just had they done that, they had less range of the very same aircraft plus all the other issues you have with that aromatic turd. Hence, you have large displacement engines. The British used "small blocks" even in their bombers. But only up to a point. The AVRO Shackleton had to have Griffon engines, as the Merlins would have to be used at a boost rating, where efficient burn is no longer possible, hence they installed the Griffon that shifted this point to a workable power region. It can be said in all fairness, the Spitfire should have been discontinued in 1942 (as should have the 109) and be replaced with the Griffon powered MB5. But both the Spit and the 109 were still great aircraft. And MB had a habit of not completing their job. The Tempest on the oher hand clearly shows what you can do with larger engine. Cruising efficietly at almost 400 mph is truly a whole new sport. Sure, you can say the 190 Dora and the late 109 could still catch them at that speed, but this is saying a sprinter is fater than a Marathon runner. And for yourself, your car is most likely specifed for 98 octane gasoline to perform as specified (it doesn't, don't put it on a bench, you'll be disapointed). This means, V-Power with 100 octane is absolutely unneeded, as your engine will not reach compression settings requiring that. BUT getting such a fuel is deeply desirable to keep your engine happy for the simple reason that it burns very clean. Also. if you dilute your gasoline with alcohol, it gets lighter and you lose milage per gallon of gas. If your fuel is turd (did I mention ARCO above?) and you put in more turd to get octane to at least 91, well, your engine will not live up to its specs and it will accumulate dirt.
  15. ZachariasX

    Tempest Mark V research

    Never cleared by Napier? Here, look again, this is by the Napier Heritage Trust: We are musting at the possible power outputs of an engine that is absolutely known to produce 3'055 by the end of the year in question here. Also it is stated that the IIb ran officially at +11 boost, but if you see a whopping 600 hp headroom, then a 13' boost becomes at least plausible. Plus there *are" people thyt you can quote saying "I used +13' boost". The Sabre is a most remarkable piston engine. I think it is even the most remarkable of the war. It by far outclasses ANY other piston engine in power to weight, power to displacement and power to frontal area. The Griffon was a good engine, but that's about it. Just a good, big fat V12. Naturally, most hated thos engine, most notably RollsRoyce, a company that was rather infamous in handling things when they felt someone was stepping on their turf. True. But those very few are more like 50 operational aircraft, rather than 5. In total, you are probably right. we will get what the devs have most info on, and this is +11 boost. RollsRoyce almost killed the plane back then, but now they could kill the memory of it by making Napier fold, erasing documentation of smaller, iterative steps to increase the power of the engine.
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