Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: Buzzbait on January 18, 2001, 04:52:00 PM
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S! all
I`ve been flying the 190a5 recently for a change. It`s actually not a bad plane if you fly without the two MGFF Cannon. Got a decent climb, accelerates quickly, especially in a dive, handles well at medium to high speeds, zooms well and has good initial turn at high speed. (although perhaps not as good as it should be) Just don`t hang around and burn `E` after you make your first pass.
Several inaccuracies I noticed:
1) The aircraft can be run on boost for ever without overheating. This is actually not the case historically. The A8 had the Methanol/Water injection system added to prevent the overheating which characterized the A4/A5 etc when using the direct injection of fuel into the supercharger which was the A5`s system of reducing overheating when on high boost.
2) The A5 should be as fast or faster than the A8 at sea level when using boost. I can send documents regarding this if someone is interested. (355mph is correct speed)
3) Even when you don`t load the MGFF outer cannon, they still show as visible on the wings. Hoping this doesn`t mean the aircraft is still paying the weight penalty for the empty guns and only saving on ammo load. In any case, this is a graphics glitch.
4) As the Luftwaffe guys have said many times, the MG34`s in the cowling could be removed. All of the 190a4`s and a5`s used in the Jabo raids against London and SW England in the summers of 1942 and 1943 had these guns removed as well as the MGFF Cannon. Another thing about the MG34`s: Many guys say they never fire the MG34`s because they are useless. Well definitely they were not very effective, historically the Luftwaffe pilots used them as and aiming guide, to sight in the cannon. When they started to get hits with the MG`s, then they opened up with the cannon. However when I try to use them this way, I instead find they are a handicap to seeing hits on the target. This is because the muzzle flashes from the MG`s are so bright they obscure your view of the target completely. I think this is historically inaccurate. The guns would not generate that big a flash, and certainly, if flash was a problem, then they wouldn`t have been used by the German pilots as gunnery aids. So muzzle flash needs to be brought down significantly.
5) The Rate of Fire of the MG151/20`s in the wing roots seems very low. I realize they were syncronized guns which were firing within the propellor`s arc, which slightly cut down on the ROF, but they seem to be really slow. Hearing them is like: Boom, Boom, Boom... not a continuous sound. Perhaps a re-examination of the ROF needs to be done here.
Cheers Buzzbait
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1) Neither of the 190's in AH are equipped with MW50. Only the 109G-10 has this installed. The A5 can run on "WEP" for 10 min in AH before it is shut down.
5)Don't listen to the sound for how many rounds are being fired. This sound is a default 20mm sound I think. By looking at the counter I get they have a ROF of about 625/min.
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2) Are these documents posted on the WEB anywhere? If not send them to me and I will post them if I have sufficient space.
5) A few versions ago I measured the ROF of these guns with a stopwatch and got 630 rounds per minute.
Hooligan
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Umm, check that machinegun model again..
its not MG34 in the planes
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S! Snefens
Hmmm.... No MW-50 with 190a8? Doesn`t sound like the historical A8. That aircraft had it as standard issue as well as GM-1 Nitrous. What`s the justification for it not being included?
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S! Fishu
If it`s not MG34, then its a 7.92mm MG anyway, which is the same for the purposes of producing a muzzle flash. The issue is the brightness and size of the muzzle flash and the effect of it on spotting rounds hitting the target. The German pilots were very able to use the small calibre weapon to align their aim and then squeeze off a burst from their big guns. In AH the flashes completely obscure the target.
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Sad as it is I've found no single trustable documentation on Fw190As being fitted with MW50. They were fitted with GM1, and the boost override for very low altitudes.
AFAIK, a lot of G and F 190s were fitted with the MW50. The A-series didnt, tho, although they had provision for it.
Here is a couple of scans I posted a while ago, explaining the boost systems used by the Luftwaffe. The A8 uses the petrol injection into the air intake. The A5 doenst. That is the reason that A8 is 15mph faster on the deck, but at 3K the speed lines of the A5 and A8 crosses not to ever cross again. The boost override works only at very low altitudes.
(http://www.airtel.net/hosting/0003d/ebringas/germboost1.gif)
(http://www.airtel.net/hosting/0003d/ebringas/germboost2.gif)
2-As I said already, no, the A5 is slower at low altitudes. Rightly so.
3-that is art only, the Fw190A8 with 2x20mm shows 4 cannons too. BElieve me, the weight of the outboard cannons is not there when you load the 2x20mm configuration. THe difference is well noticeable.
4-MGs on the cowling are MG15, not MG34. I doubt about the "firing MGs before cannons" unless they were at very low ranges, they have very different ballistics.
I also find them useless, and I'd love to see the option to get rid of them at all. BTW the A5s used in UK for fast slashing bombings were Fw190A5/U3. Those had wing racks for wing bomgs, or DTs. those had also central rack for multiple bombs.
Leter, those planes' designation was changed, and they were known as Fw190G3. (HINT HINT ; WHY NOT MAKE THE 190A5 BE CONFIGURED AS A G3?)
5-ROF of mausers suck. I dont know if rightly or not. But I find highly questionable that with a ROF of 650 rpm ,the bandits are able to cross my bullet streams without getting hit. This happens a lot to me (and to more 190 drivers).
[This message has been edited by RAM (edited 01-19-2001).]
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S! Ram
I am very familiar with the pages you are showing. They are from the engine section in the very back of "Jane's Fighting Aircraft of WWII" and are of course a secondary source.
I don't have a scanner and don't know how to post documents on this board so I may just send you the material directly. I may also hand you over to another fellow who is more of an authority on the 190 and who has all the documents from original sources.
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If you have a primary source indicating that MW 50 was used on any Fw 190A models, I would love to see it!
The best I have is a translation of the pilot's handbook which indicates that the A-8 used a boost override system that was dry (no MW 50), and that GM-1 was an option. Performance charts accompanying the manual indicate the 355 mph speed at sea level was obtained using the boost override. The manual also describes the supplementary petrol injection system but indicates that it had been phased out of production.
[This message has been edited by funked (edited 01-19-2001).]
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Originally posted by Buzzbait:
S! Ram
I am very familiar with the pages you are showing. They are from the engine section in the very back of "Jane's Fighting Aircraft of WWII" and are of course a secondary source.
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I agree with funked. Any documentation you have on instalation of MW50 in Fw190As will be greatly welcome here (email is on the profile)
BTW the pages I posted-yes, from Jane's- are not to proof anything, but as a description of the systems used by the germans as boosters. Its a fairly good and short enough description, short enough to post it here (http://bbs.hitechcreations.com/smf/Smileys/default/wink.gif)
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Originally posted by RAM:
...But I find highly questionable that with a ROF of 650 rpm ,the bandits are able to cross my bullet streams without getting hit. This happens a lot to me (and to more 190 drivers).
[This message has been edited by RAM (edited 01-19-2001).]
This happens to me every day.
Lets suppose a general ROF of 650 RPM for the 4x20 in A8, lets suppose you are perpendiculary aligned with the enemy flight path, lets suppose the enemy length is 10 meters and is flying at 350 kmh. You start firing before the enemy crosses in front of you, and, of course, you'll have chance to hit that plane just while its entire lenght crosses your fire zone. A 10 meters plane will spend 0.103 seconds to advance 10 meters flying at 350 kmh. So, you'll have some part of the enemy in front of any of your guns just for 0.103 seconds. In 0.103 seconds your 4x20 will hit 4.46 times the enemy plane.
As you can see, this is an extreme example with an enemy crossing fast in front of you.
My main problem with 151/20 is the aiming. You have tracer... ...an eternity.. ..tracer.. ..an eternity.. ..tracer.. You have little chance to correct your aiming point based on the tracers. This could be a ROF related problem, or it could be just because we have 50 bullets between tracer and tracer.
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650 RPM for the Mg151/20 is certainly too low.
Name Ammunition Rate of Fire Muzzle velocity Weight
Oerlikon F 20 x 72RB (144 g) 500 rpm 550 m/s 24 kg
Oerlikon L 20 x 101RB (144 g) 350 rpm 670-700m/s 43 kg
Oerlikon FFL 20 x 101RB (144 g) 500 rpm 750 m/s 30 kg
Oerlikon S 20 x 110RB (122 g) 280 rpm 830 m/s 62 kg
Oerlikon FFS 20 x 110RB (122 g) 470 rpm 830 m/s 39 kg
MG c/30L 20 x 138B (119 g) 350 rpm 900 m/s 64 kg
MG FF 20 x 80RB (115 g) 520 rpm 570 m/s 28 kg
MG FF/M 20 x 80RB ( 92 g) 520 rpm 690 m/s 28 kg
MG 151/20 20 x 82 (115 g) 740 rpm 710 m/s 42 kg
MG 151/20 20 x 82 ( 92 g) 740 rpm 800 m/s 42 kg
ShVAK 20 x 99R ( 96 g) 800 rpm 800 m/s 42 kg
B-20 20 x 99R ( 96 g) 800 rpm 800 m/s 25 kg
Hispano Mk.II 20 x 110 (130 g) 600 rpm 880 m/s 50 kg
Hispano Mk.V 20 x 110 (130 g) 750 rpm 840 m/s 42 kg
Type 97 (Ho-3) 20 x 125 (164 g) 400 rpm 820 m/s 43 kg
Type 1 (Ho-5) 20 x 94 850 rpm 750 m/s 33 kg
Type 99 mod 1 20 x 72RB (142 g) 490 rpm 555 m/s 23 kg
Type 99 mod 2 20 x 101RB (142 g) 490 / 750 rpm 750 m/s 36 kg
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Jekyll those are rates for unsynchronized guns.
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OK funked, and your point is?????
I always understood the outboard cannon on the 190s WERE unsynchronised. If you time the outboard guns on the 190A5 you will find that they only fire at about 620-630 RPM. That's way low for the 151/20.
500 shells, 250 per gun. Guns empty in 24.84 seconds. Test it yourself if you like.
Interestingly, the CHog outboard hispanos (presumably Mk IIs), fire at 632 RPM compared to 600 RPM in the above table. The inboard cannon fire at 651 RPM.
[This message has been edited by Jekyll (edited 01-19-2001).]
[This message has been edited by Jekyll (edited 01-19-2001).]
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In AH:
The outboard guns fire at 700 and the inboard guns fire at 630. These numbers match the ROF information I have seen in Rechlin test documents.
http://home.earthlink.net/~jayboyer/b-20mmTabelle4.jpg (http://home.earthlink.net/~jayboyer/b-20mmTabelle4.jpg)
Hooligan
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Jekyll:
My point is that the discussion in this thread concerns the inboard, synchronized cannons. The 190 was fitted with an interrupter mechanism which prevented the inboard guns from firing when a propellor blade was in front of the muzzle. This reduced the rate of fire by about 10%.
I did the same test in the game and found that the guns run out of ammo in a hair less than 24 seconds, which gives about 625 rpm. 625 rpm is about 90% of 700 rpm which is the unsynchronized rate of fire.
The weird thing is that if you do the test with the outboard MG 151/20 loaded (on the A-8), all four guns stop firing at the same time. This implies that the outboard guns are firing a rate of 350 rpm, or they have a double ammo load, or it could be that all four guns fire at the same rate, and the ammo load is distributed equally between them.
In any case, it's not right. The outboard guns should fire at the full rate and expend their ammo in 12 seconds.
[This message has been edited by funked (edited 01-19-2001).]
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Oops I was wrong. The outer cannons DO run out of ammo after 12 seconds. It's just that the muzzle flashes keep showing. I figured it out by taxiing over to hangar and shooting it. There were four sets of hit sprites for the first 12 seconds, then 2 sets of sprites for the last 12 seconds. So the rates of fire and firing times for the outboard MG 151/20 are correct. (60 sec/min) * (140 rounds) / (12 sec) = 700 rounds per minute.
[This message has been edited by funked (edited 01-19-2001).]
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Maybe thats because the outer cannons in the A5 are MG FF and not MG 151/20?
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S! RAM and FUNKED
I am trying to contact my acquaintance who has the document sources. Will let you know.
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Funked is right here..
with continous fire you will still see muzzle flash even after one set of guns are empty
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Originally posted by Buzzbait:
S! RAM and FUNKED
I am trying to contact my acquaintance who has the document sources. Will let you know.
Can't wait (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif) I hope you are right!
AH's Fw190A8 with MW50....allied yalls on the sky.....YUMMMMM!!!!!! (http://bbs.hitechcreations.com/smf/Smileys/default/biggrin.gif)
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Nath: DOH I'm an idiot, I tested the A-8 not the A-5. I guess I was fixated on the MG 151/20.
RAM: Keep in mind that the performance of the current A-8 is equivalent to that claimed for MW 50. Unless these new documents have some new performance data, don't expect things in AH to change. I still think we should have GM-1 though, for those stratoBUFF intercepts. (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
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Looking at that document, I cannot help but notice one sort of rounds:
MG151/20 2cm geschosspatrone 805m/s
Is that a tracer round?
What's the difference between the MG151 and the MG151/20?
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Baron Claus "StSanta" Von Ribbentroppen
9./JG 54 "Grünherz"
(http://www.geocities.com/nirfurian/stSanta.jpg)
"I am the light at the end of your sorry little tunnel." - A. Eldricht
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Mg151 is the 15mm version.
Mg151/20 is 20mm.
That round is the Mine round. I believe the , el nomenclature indicates the tracer variety (and L'Spur is self-destruct) although I am too lazy to look it up at the moment (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif).
Hooligan
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DOh Iit says so on the page
New question: what velocity does the MG151/20 have in AH?
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Baron Claus "StSanta" Von Ribbentroppen
9./JG 54 "Grünherz"
(http://www.geocities.com/nirfurian/stSanta.jpg)
"I am the light at the end of your sorry little tunnel." - A. Eldricht
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Originally posted by funked:
RAM: Keep in mind that the performance of the current A-8 is equivalent to that claimed for MW 50. Unless these new documents have some new performance data, don't expect things in AH to change. I still think we should have GM-1 though, for those stratoBUFF intercepts. (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
Funked, no
Watch the pages I posted about the petrol injection on the air intake (the booster the 190 has). It increases the performance of the BMW801D from 1730hp (roughly) to 1870hp. That is 140 hp, noticeable, but still FAR away from the estimated 2100hp performance that MW50 booster gave to a BMW801D, according to most sources.
Plus, the MW50 booster works up to 22K feet aprox. The petrol injection does it ONLY at VERY low altitudes.
I'd get the MW50 ALL day over the petrol injection boost (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
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Mandoble, while your math is correct, you forgot a few very important variables. First, the target is not a rectangle. You are shooting at something that is (fighter) around 10 ft across on the fuselage. Something as small as a wing or tail could easily pass between the rounds. You also aren't taking into account dispersion. You also are assuming that your plane is not moving in relation to the enemy. The last factor is that you are assuming the shells coming from a single gun. Since they are mounted in the wings and set to converge at a point, the equations become a little more complicated.
You would only achieve 4 hits if the first round struck the engine cowl and the rest were perfectly alligned with the fuselage.
WHEW this is all too complicated; lets just mount laser beams in the cowl (just like Tie fighters.) (http://bbs.hitechcreations.com/smf/Smileys/default/biggrin.gif) (Btw: My Hispano gun sound is a clip of the lasers from Star Wars. (http://bbs.hitechcreations.com/smf/Smileys/default/biggrin.gif) (http://bbs.hitechcreations.com/smf/Smileys/default/eek.gif) I end up ROFL every time I strafe a target in a Typhoon. )
I realize this isn't really on topic, but I felt like posting, so I did. (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
(Btw: If you think it's hard trying to shoot moving targets with the MG151, try the Shvak in the Yak or La5. )
I now return you to your regularly scheduled thread, already in progress. (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
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bloom25
THUNDERBIRDS