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JtD

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  1. No, 29500ft is not higher 30000ft. 31000ft for instance are. With a power gradient of about 100hp per 1500ft of altitude, it is lacking 100hp due to the low full throttle altitude alone. And it used water injection at altitudes above 30k and obtained less than 420mph at 31k. Yes, 100hp less. Below full throttle altitude. Give it a good full throttle altitude, a bare metal finish and the best prop available, and you'll have it go 435@31k.
  2. At 56" it is still lacking compared to other P-47's tested, which maintained 56" up to altitudes > 30k.
  3. Interesting report, thanks for linking that. On your above sentence - it would be at the limit if it used a RAF14 airfoil. However, with the airfoil it used, the safety factor is 2 and 3 for front and rear spar. It should also be mentioned that once you pull out of the dive (produce lift), the moment in the wings should be reduced and you gain some margin for a pull out g-load (unless the safety factor on the rear spar is smaller than that on the front spar in the diving condition).
  4. Both the HUD and the indicator show CAS in game. Glad to see someone here who knows there's a difference. If you look at the figures of the D 44-1 fuel report, you have to consider that it is performing pretty poorly. In particular its high altitude performance is off compared to most other tests, with a low full throttle altitude. You don't need more power for better performance, you need a better aircraft (condition). Maybe a bare metal polished one instead of one painted in standard camo. Or one fitted with a Hamilton 6507A2 prop instead of the Curtiss one, giving 5-8 extra mph. A small plus might be that it is a razorback D. They also don't say what turbo rpm they used. Not sure if you mentioned all that, because I only skimmed this last page.
  5. This is modelled based on (atmospheric) pressure and boiling point physics, and as I've already stated, the MiG-3 apparently ran at 1.4atü. But I've also aready quoted the devs that this is implemented, and still you tested it? Here are tables and charts that give water boiling points over pressure: https://www.engineeringtoolbox.com/boiling-point-water-d_926.html Mig-3 1.4atü -> 2.4ata (2.4bar for ease of conversion) at sea level, 1.4ata in vacuum (or say 1.7ata at altitude). Boiling points: 126°C down low, 110°C in vacuum or 115°C at altitude. Limits in the manual are 5° lower than that (120° for take off, 110° in flight). Makes sense. Different aircraft -> different pressure, different coolant (for instance glycol) -> different boiling points. If I were you, I'd take what you have on the MiG-3 and contact the devs about it (PM Gavrick), or write a bug report in the much ignored bug report section of the forum.
  6. He means that historically there are occasions of Mustangs outturning 109s and vice versa. Technically they were close enough in performance to allow pilot and circumstances to make the difference.
  7. If no wires were there the upper and the lower wing would not work as one structural member but as two separate ones, when it comes to taking the g-load. And given that height of the sturctural member factors in as cubic factor, you can imagine that these wires were pretty important. Say you have two 10cm high wings wired together as a perfect 1m high load bearing twin plane structure - if you lose the wires, you end up at less than 1% the strength of the wired construction. Question is, did the wires really take these loads or were they just supports and if so, to what degree?
  8. Excuse my ignorance of WW1 aircraft - but weren't g-loads (and other loads) taken mostly be the wiring of the wings? Shouldn't it be therefore pretty simple to get a fairly accurate idea of permissible g-loads by getting the dimensions and material properties of the wires? The wings would hardly factor in, with the exception of late German designs, which had load bearing functions as well (thick wings).
  9. Ailerons and elevator are often of Frise type or simply of asymmetric nose shape, rudder hardly ever is. It gives them less linear force-over-angle characteristics, and they are more prone to overbalancing and erratic movement, in particular in case of damage, where airflow can be erratic. Can't say if that is modelled properly, but it might be what they were aiming for.
  10. Yeah, it's protected by impenetrable 1mm aluminium armour. And I've heard it shoots lasers, too.
  11. The Fw190 had an armoured oil ring/cooler/tank, not armoured cowl flaps. The only aircraft to qualify in some way as having armoured radiator flaps is the Il-2, which had two armour grade steel outlet flaps of 5mm thickness. Any other radiator flap used in WW2 I can think of wouldn't even protect against rifle calibre bullets. Complete list of armour on the A-8 subversions:
  12. A Bf110C cockpit image shows another type of placard. I'd say it says "km 10-5-0" and that there are markings corresponding to the temperature limits of the manual. These placards aren't present in the poor quality images of the manual. Since these placards are easily made in your local workshop, they may have well been added as an afterthought at any point between the production line and front line squadron activities, and that in many forms. The purpose probably was to indicate the safe operating zones, which are not on the actual temperature gauge. But unless someone finds dozens of high quality images of WW2 Bf109G cockpits, I guess we'll never really know what exactly was done how back then, and if they indeed painted wrong limits on some of them. Bf110C image (temp gauges labelled 14 low centre panel): https://www.deutscheluftwaffe.com/archiv/Dokumente/ABC/e/Ereignisse/bilder/gross/007.jpg Personally I wouldn't use them at all, because of the performance impact of the added weight.
  13. Totally agree with you, that placard is a placard of many questions. I found a parts number in a Bf109G component list, says 109.954, but that doesn't lead anywhere. I also think that for the most part we should ignore pictures of restored 109's, because all too often they are wrong in some details. In the picture you posted last, the placard seems to have been added at a later date, it looks much more fresh than everything else. I also note the screws are painted in a glossy black, while most other (probably original) screws are painted in a matt grey. Doesn't really add trust.
  14. This is interesting. The Bf109 manual states at Fl20343 switchable temperature gauge is to be used. It goes to 160° and can display oil inlet temp when the button on the top right is being pressed (as with the Black6 picture you posted). The data sheet below states it is not supposed to be used for new models. There also is a Fl20342 non-switchable temperature gauge, which goes to 130°, and says is supposed to be used as a replacement for the Fl20343 switchable gauge. Now the interesting bit is, that in your picture, the gauge is ending at 130° and is missing the switch-button in the top right corner. It's not a 20343, likely a 20342. But the frame still says "press the button", and I wonder if the markings put on the green-red bar on top of the gauge still come from an original 20343. Interestingly enough, the in game version is also a mix, but a wrong one, as it is missing the switch button. https://www.deutscheluftwaffe.com/downloads/Dokumente/Geratezeichnungen/20000-22000/Blatter/Fl20343.gif https://www.deutscheluftwaffe.com/downloads/Dokumente/Geratezeichnungen/20000-22000/Blatter/Fl20342.gif Please also note that on the 109 the radiator was automatic and set to control the coolant temperature at 102°, independent of altitude. Any markings below that temperature can't really have operational meaning to the pilot. The DB605A cooling system ran at 1atü and was good for 106° at 15km altitude, according to the DB605 manual. Edit: I found the figures for the markings of 78° at 10km and such already in a May 1941 Bf109F manual, it's exactly the same text. Which is wrong already there, and definitely a leftover from earlier versions. The correct version for a Bf109G would probably look like this, which corresponds to the figures from the compact flight manual: https://upload.wikimedia.org/wikipedia/commons/9/96/Messerschmitt_Bf_109_G-6R3_Cockpit.jpg Regarding the Mc.202, I found that it used a "special Aer. Macchi valve" that weighs 620grams. No information about pressure. Please note that even closed systems running without over-pressure would need some sort of pressure valve, otherwise an overheating coolant would simply blow a line or a joint and never seal for the rest of the flight if the coolant temperature drops again. I've also read that the temperature should not exceed 95° E and 103° U in a climb, which I'd wager are engine in and engine out temperatures. The Mc.202 uses a licence built DB601Aa, which, afaik, used the temperature limits given by Raven109 and me before. These values supposedly are "6° below the boiling point", fwiw. The DB601Aa had an pressure valve rated at 0.3atü, according to a Bf109E export description. I suppose the devs went with the same figures for the Mc.202. I have no data that explicitly says otherwise, might be a good idea to ask our Italian community members. At the very least they speak Italian, which I don't. It's possible the cooling system on the Mc.202 was upgraded to later DB601/DB605 standards, we'd just need some more info on that. Giving 103° as a limit in a climb does not make sense if that's higher than the physical maximum already at 2km altitude...but that's no hard data, just an indication.
  15. Guilty as charged. I'd suppose the markings come from the reference I gave, plus some artistic freedom. The boiling point of pure water at 10km altitude is around 75°. The way I read the MiG-3 manual, the MiG radiator ran at 1.4atü with (pure) water, which should be good for 125° at sea level and 110° basically in vacuum. This agrees with the manual which states 120° on take off and 110° in flight, with the pressure gauge at 1.2-1.5at. So operational limits slightly below the physical ones. The water temperature is being measured at the engine outlet, so it is the hottest point and no hidden reserve is needed. Imho, the MiG-3 should not "overheat" at 100° at altitude.
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