Kurfürst

Staying with the radiators - I noticed on the video that the radiator flap control seems wrong. In DCS video, it has 4 positions (which is correct): Automatisch (auto) - top position Zu (close) - left position Auf (open) - right position Abgeschlossen (close) - lower position The Abgeschlossen (closed) - lower position is wrong! The real thing had label "Ruhe" (Still or in this context, Off) position in this place, which switched the motion of the radiator flaps off. See the attched picture from the K-4 manual (K-4 Flugzeug-Handbuch Teil 00, P. 27), in which the Ruhe text can be faintly seen. I believe the Zu and Auf positions were gradual and continous opening/closing the rad flaps to fully open or closed positions (I do not know how fast but probably slow). The pilot would leave the switch at these positions until the desired rad flap opening was achieved, and then turn the switch to "Ruhe" to fix them in that position. Alternatively, he could leave it of course in the Automatic position and forget about the whole thing. :)

Yes, I believe the text stands for SeitenLeitWerk Voreinstellung -1.7 degrees. In the meantime I have found the F/K-series wing on which the wing profil is identified as 2414 (root) and 2411 (wingtip). It seems to be hand written note so it may be either someone's ex post facto guesswork or authentic... Apparantly not, the respective engine sheets of the DB 605A at 30-min rating (1310 PS output) and the methanol-water injected/boosted 605AM (same engine) for the wet WEP (MW50) rating of 1800 PS practically give the same cooling requirements of 340/345 000 kcal/h, despite the radically more power. So in short the methanol boosted engine running at much higher output does not appear to need a lot more cooling at all. Probably a result of the internal cooling effects of methanol-water (MW 50 injection), but its curious why, given that the amount of water injected may not answer it alone. Bottomline, if the above specs are true, the cooling capacity of the 109G was already generous for the 1,3ata rating as test show, so my guess would be that the radiator flap exit was limited in order to prevent the system from causing excessive drag, as 220 mm would be sufficient. Though cold winter conditions can explain as well the implementation of such measures. I believe its an early 1,8ata version which would be more representative for the late 1944 condition of 605DM and DB engines plus all the others seem to be the "normal" boosted versions. The '51 definietely is.

PS - one some of the pictures found on 109K, some planes have a notice painted on the radiator flaps that the opening is limited to 220 mm. The normal opening was ca. 350 mm. My question is if anyone knows the reason for this (lower drag..?) and if this is implemented in DCS 109K model ?

This might help. I remember seeing a similar 109(G?) wing plan, which seemed original, and on which the 2R1 was also noted to be NACA 23xx series. But it is true its somewhat of a mystery profile. This is for the 109F tail assembly for interest.

Probably too late to change anyway.

Wonderful news. Thanks for the update! :)

Well supposedly the K had some improvements in ground handling as well, it may have been the most docile 109 on the ground because of them. of course there is not much testing or reports on this, but physics work the same with known values... we will see, but certainly unleashing all the power does seem to be a bad idea! :)

Two weeks be sure!

Maybe they want ethanol sacrifice to.... booost things. :D

Maybe the Gods are angry with us and we need to please them with sacrifice.

November was only for beta afaik

A p-47..? :lol: Seriously, it might, given the power & altitude.

Oh I see. That's a wonderful little airfield there too. And the buffet is great, too! :thumbup: P.S. I have been in the inside. Just ask the old gentleman (Curator/Guide/Ticket seller, all in one as I understand! :D I hope he is all well, looked very old when I was there.. ) to let you in and open it up. I did! :)

"LOAN"...? Its the one in Wiener Neustadt, Austria, an ex-G-14/AS from Bodenplatte and recently restored by some friends. Quite an engine section there, if you ever wonder there, really rare things. Said to have been dozered into a hole next to the airfield in 1945, so they had to just dig them out and wash them down. :)

I very much hope so, LOL! :pilotfly: Anyway, here is a picture I took of a leading edge slot of a G-6/14, it shows some details.

Be assured that in my experience, development is only based on reliable information and data from archives and acknowledged contributors. That has been true for all the projects I have been involved with. Those most vocal, ever present, ever under a new handle, ever replying members who have all the time in the day to spout out their "contributions" never get the attention they desire. :)

There is nothing to open them i suppose. the real thing got sucked out by the airstream at high angles of attack, though you can move them very easily on the ground, too.. its basically a piece of formed metal, moving on rails.

Excellent job! :thumbup:

Luckily its up to the devs to decide what is relevant - and the more data, the better! :D In any case, sadly not much is heard about the Spitfire development so far. Hopefully, there will be some updates in foreseeable time...

Some various Some additional gun dispersion data, via Olivier Lefebrve / AAW. This might come in handy for modelling the Hispano guns on the Spitfire IX. Unfortunately only nose mount dispersion data available for the gun, as mounted in the P-38 nose, but given that German results for the same guns in the fuselage and wings display roughly 2-2,5x higher dispersion for wing mounted installations, it would be easy to make an educated guess for the dispersion of the Hispano, and if we get an E variant, for the .50 M2s in the flexible Spitfire wing. The .303 Brownings had a quite large spread in wing installation, iirc around 20 mils for 100%. Here are the results of a lenghty research into dispersion data, which is quite hard to come by... The data is based on 100% diameter dispersion with 1 mil = 1/1000th of rad, the kind of mount is precised next to the weapon. 75% dispersion diameter is supposed to be half the 100% diameter which seems quite true for most weapons, this value is provided when quoted in the source (M2 data for instance). We can clearly see the impact of the wing mounting compared to engine mounting, the later seems to have absorbed recoil and vibration much better... indeed dispersion is at least 2 times greater with wing mounted weapons. Engine mount are the most efficient but nose mounting or cowling mounting does not provide the same amount of precision the mount being much more prone to vibration it seems. Note that US data on the M2 is confusing since the reference data comes from a P-38 nose mounted M2, but the US manuals use the same dispersion data for wing mounted weapons. Either the P-38 mounts are really up to no good or the manuals make a wrong assumption when it comes to wing dispersion. I tend to believe the later, i think the wing mounted M2 would have had a dispersion of at least 12mils and probably more. If you quote this data on other sites/bbs please precise the source being AAW. TIA H means Height (or max dispersion diameter) as i previously used vertical and lateral dispersion values. D means distance. Units are metric. German Weapons ----------------------- MG-17 Cowling mounted (Bf 109F-2 / Bf 109F-1 actual tests) H = 0.60 / 0.8 m D = 100 m R/D = 60/10000 80/10000 = 6 mils / 8 mils MG-131 Cowling mounted (Fw 190A - theorical max) H = 1m D = 100m H/D = 100/10000 = 10 mils MG-151/15 Engine mounted (Bf 109F-2 actual test) H = 0,35 m D = 100 m H/D = 35/10000 = 3.5 mils MG-FF Engine mounted (Bf 109F-1 actual test) H = 0,2 m D = 100m H/D = 20/10000 = 2 mils (very tight patern) MG-FF Wing mounted (Bf 109E-3 actual test) H = 0,35 m D = 100m H/D = 35/10000 = 3.5 mils MG 151/20 Engine mounted (Bf 109G-6 - theorical max) H = 0.3m D = 100m H/D = 30/10000 = 3 mils MG 151/20 Wing mounted - inner (Fw 190A - theorical max) H = 0.7m D = 100m H/D = 70/10000 = 7 mils MG 151/20 Wing mounted - outer (Fw 190A - theorical max) H = 0.8m D = 100m H/D = 80/10000 = 8 mils MK 108 Engine mounted (Ta 152 - therorical max) H = 0.35 D = 100m H/D = 35/10000 = 3.5 mils Allied Weapons ------------------ M2 Nose mounted P-38 (USAAF 1944 Gunnery manual) H = 1.88 m D = 229 m H/D = 188/22900 = 8.2 mils (75% = 4.1 mils) Hispano 20mm Nose mounted P-38 (USAAF 1944 Gunnery manual) 3 mils 75% 6 mils 100% assumed

Some additional gun dispersion data, via Olivier Lefebrve / AAW: Here are the results of a lenghty research into dispersion data, which is quite hard to come by... The data is based on 100% diameter dispersion with 1 mil = 1/1000th of rad, the kind of mount is precised next to the weapon. 75% dispersion diameter is supposed to be half the 100% diameter which seems quite true for most weapons, this value is provided when quoted in the source (M2 data for instance). We can clearly see the impact of the wing mounting compared to engine mounting, the later seems to have absorbed recoil and vibration much better... indeed dispersion is at least 2 times greater with wing mounted weapons. Engine mount are the most efficient but nose mounting or cowling mounting does not provide the same amount of precision the mount being much more prone to vibration it seems. Note that US data on the M2 is confusing since the reference data comes from a P-38 nose mounted M2, but the US manuals use the same dispersion data for wing mounted weapons. Either the P-38 mounts are really up to no good or the manuals make a wrong assumption when it comes to wing dispersion. I tend to believe the later, i think the wing mounted M2 would have had a dispersion of at least 12mils and probably more. If you quote this data on other sites/bbs please precise the source being AAW. TIA H means Height (or max dispersion diameter) as i previously used vertical and lateral dispersion values. D means distance. Units are metric. German Weapons ----------------------- MG-17 Cowling mounted (Bf 109F-2 / Bf 109F-1 actual tests) H = 0.60 / 0.8 m D = 100 m R/D = 60/10000 80/10000 = 6 mils / 8 mils MG-131 Cowling mounted (Fw 190A - theorical max) H = 1m D = 100m H/D = 100/10000 = 10 mils MG-151/15 Engine mounted (Bf 109F-2 actual test) H = 0,35 m D = 100 m H/D = 35/10000 = 3.5 mils MG-FF Engine mounted (Bf 109F-1 actual test) H = 0,2 m D = 100m H/D = 20/10000 = 2 mils (very tight patern) MG-FF Wing mounted (Bf 109E-3 actual test) H = 0,35 m D = 100m H/D = 35/10000 = 3.5 mils MG 151/20 Engine mounted (Bf 109G-6 - theorical max) H = 0.3m D = 100m H/D = 30/10000 = 3 mils MG 151/20 Wing mounted - inner (Fw 190A - theorical max) H = 0.7m D = 100m H/D = 70/10000 = 7 mils MG 151/20 Wing mounted - outer (Fw 190A - theorical max) H = 0.8m D = 100m H/D = 80/10000 = 8 mils MK 108 Engine mounted (Ta 152 - therorical max) H = 0.35 D = 100m H/D = 35/10000 = 3.5 mils Allied Weapons ------------------ M2 Nose mounted P-38 (USAAF 1944 Gunnery manual) H = 1.88 m D = 229 m H/D = 188/22900 = 8.2 mils (75% = 4.1 mils) Hispano 20mm Nose mounted P-38 (USAAF 1944 Gunnery manual) 3 mils 75% 6 mils 100% assumed

Also one of the rare occasions I actually agree with Holz. this might prove interesting. http://forums.eagle.ru/attachment.php?attachmentid=107361&stc=1&d=1415955237

Gauss. You are looking for Gauss.

The GAU 8 may be well one of the most accurate large caliber Gatling guns, and as close to perfect for the job it was meant to do, but its pointless to compare it to the others, be it small caliber, single shot bolt action rifles or 120mm APFSDS tank guns. You build a Gatling for Rate of Fire, not for accuracy. In any case, the GAU 8 has nothing to do with the K-4.

Yes, provided that the said accuracy would change much with maximal distances up to and around 1000 m.. or that flight simulations would bother with calculations for each round, based on complex ballistic tables detailing data for 100 meter intervals, including corrections for humidity, temperature etc. :doh: