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dwaindibley
10-19-2007, 12:59 AM
Does selecting extra ammunition for the Jug give any performance penalty in IL2 1946 (v4.08)? I'd assume extra weight but I don't notice any difference myself but I'm a very casual player although I do use all the "real" options for engine, flight model ect.

Also I'd be interested if there is any historical basis for this option on the P47. Increased range?

Oh, and one more question while I'm here can anyone share their views on gun convergence. Best to have all 8 the same or 4 at say 175m and 4 at 225m which seems to work quite well.

Thanks in advance.

Bearcat99
10-19-2007, 05:13 AM
I don't think it is too much of a performance hit.. none that I notice. I find that that is not a bad convergence.. although I set mine depending on what I am doing.. I set it a little longer for groundwork. I also have mine set similarly.. with a 50M difference.. but I sometimes set them all the same.. experiment and find what suits your skills.

JG53Frankyboy
10-19-2007, 05:15 AM
Originally posted by dwaindibley:
Does selecting extra ammunition for the Jug give any performance penalty in IL2 1946 (v4.08)? I'd assume extra weight but I don't notice any difference myself but I'm a very casual player although I do use all the "real" options for engine, flight model ect.

Also I'd be interested if there is any historical basis for this option on the P47. Increased range?

Oh, and one more question while I'm here can anyone share their views on gun convergence. Best to have all 8 the same or 4 at say 175m and 4 at 225m which seems to work quite well.

Thanks in advance.

http://forum.1cpublishing.eu/viewtopic.php?t=260

VMF-214_Pappy
10-19-2007, 06:31 AM
I have played around with 150m to 300m is us aircraft and the JUG, what seems to work best for me is both set at 225m where i tend to open fire usually, i get alot of fires, controls and de-wings this way and it is totally devistating to anything wearing a red meatball.

TgD Thunderbolt56
10-19-2007, 06:41 AM
Originally posted by VMF-214_Pappy:
...it is totally devistating to anything wearing a red meatball.

A BB gun is totally devastating to anything wearing a red meatball. http://forums.ubi.com/images/smilies/blink.gif

There IS a performance hit on the extra-ammo option albeit not too severe. Kinda the equivalent to an extra 25% fuel. As far as convergence in the Jug, I've been using 350m inner, 400m outer for years and most all my shots are high-deflection. Whether by preference or opportunity I couldn't say, but I think it's a combination of both.

TB

HotelBushranger
10-19-2007, 06:59 AM
Btw welcome to the forums dwain http://forums.ubi.com/images/smilies/25.gif

Kernow
10-19-2007, 07:00 AM
Originally posted by dwaindibley:
Also I'd be interested if there is any historical basis for this option on the P47.
Almost certainly it is historical; I think all loadouts and weapons for any aircraft were at least tried once or twice for real, even if they never became widely used. But I don't know for sure in this case.

I use 150 m for anything with less than 4 x 20 mm cannon and only shoot at close range. If I knew I was going to be strafing I'd set something more like 300 m, rather like Bearcat said. I use the P-47 for B&Z, which often only gives a second or so of firing time. I've often wondered is opening up earlier and with a longer convergence would be better. However, I suspect the earlier warning would just allow the bad guy to jink out the way before I was close enough to do real damage, so I stick with 150 m and last moment shooting. Unless I completely screw up the shot or get a bad screen freeze that is enough to take them out of the fight even if it doesn't result in instant death. Generally I don't waste my E just to finish them when 3 times out of 4 they bail or crash within 5 mins anyway. If the other one-in-four manages to land, good luck to him (and you'll still get the points, if that matters).

BOA_Allmenroder
10-19-2007, 07:14 AM
Ok, I'm going to ask the obviously stupid question, but how do you set different guns at different ranges? All I see is the one settng in the game? Do you have to go into the config file?

Geez, and I've been playing this for several years.... http://forums.ubi.com/images/smilies/53.gif

Skycat_2
10-19-2007, 07:15 AM
Very briefly: The P-47 design could carry 425 rounds per gun maximum. However, operational charts recommended loading about 300 rounds per gun as the operational limit. I've also seen recommendations for six (instead of eight) gun configurations so maybe removing two guns allowed the weight of full ammunition to the remaining guns (ie, 6 x 425 rpg).

The charts I'm referring to are for the B, C and early D models even before wing pylons were introduced. Maybe after the wings were strengthened in production, planners were more comfortable with full ammunition loads in the wings if other stores weren't hung underneath?

TgD Thunderbolt56
10-19-2007, 07:22 AM
Originally posted by BOA_Allmenroder:
Ok, I'm going to ask the obviously stupid question, but how do you set different guns at different ranges? All I see is the one settng in the game? Do you have to go into the config file?


The P-47's 8 MG's are seperated into an inner bank of 4 and an outer bank of 4. The outer bank uses the same convergence settings you have assigned to your cannons while the inner bank uses the setting for machine guns.

dwaindibley
10-19-2007, 10:08 AM
Thanks guys I appreciate the info. I've been dipping in and out of IL2 for the last 2 years or so and have tried my ham fisted hand at many of the planes but find I still end up coming back to the P47. I love her looks, nice cockpit layout, survivability and plenty of firepower plus I feel she really teaches me the value of energy ie. once you cash it in you'd better use it or else ...

TgD Thunderbolt56 thank you so a bit less fuel = more spray for my pray i think that's a fair exchange rate!

Skycat_2 and JG53Frankyboy that's really interesting info just what I was looking for.

VMF-214_Pappy and Bearcat99 it sounds like I'm in the right area at around 200m +/- so I think I'll stick with that but try and learn to shoot straight.

HotelBushranger I'm a medium time lurker first time poster so hello to you and everyone else here. I find this a very interesting and useful forum and in no way a zoo.

Once again thanks to you all.

Stew278
10-19-2007, 10:29 AM
Originally posted by TgD Thunderbolt56:

The P-47's 8 MG's are seperated into an inner bank of 4 and an outer bank of 4. The outer bank uses the same convergence settings you have assigned to your cannons while the inner bank uses the setting for machine guns.

Wow, I never realized that. Are there any other planes where we can set the MG's with different convergences?

Cajun76
10-19-2007, 11:35 AM
That's the only one that I know of. If you notice, you have to use both MG and cannon triggers for all 8 guns in the Jug to fire. So convergence settings correspond to the separate triggers. No other MG only a/c that I know of has that, even the 12 gun Hurricane fires all 12 with Weapon 1.

My personal setting is 300 for MG and 250 for "cannon". I believe it was Blutarski that did an analysis of the the dispersion vs convergence and determined that 250 to 300 was optimal. Additionally, the MGs are the outer pair and the "cannon" are the inner.

I noticed that when MG was 250 and cannon were 300 (the reverse of my settings) that it left a gap in the pattern where they crossed paths. Very concentrated at those spots, but they are at least 15 feet (4.5m) apart. With your gunsight centered on the target, many fighter sized targets are hard to hit like this.

BOA_Allmenroder
10-19-2007, 11:54 AM
Wow, thanks TdG and other Jug drivers. http://forums.ubi.com/images/smilies/25.gif Does the same apply to the P51 6 gun models: NT and NA?

Cajun76
10-19-2007, 12:05 PM
No problem. P-51 uses only 1 trigger for all 6 guns. Only MG convergence is going to apply. The inner pair does carry more ammo than the outer 2 pairs do in normal loadout.

The Jug is unique in the game for this, but most planes IRL could select different combinations of guns.

IIRC, a Wildcat pilot swore to keep 1 pair of guns in reserve and use only use 1 pair at a time after running out of ammo in a critical situation.

Skycat_2
10-19-2007, 08:19 PM
I found and interesting item in the book Warbird Tech Series Vol. 23, Republic P-47 Thunderbolt by Frederick A. Johnsen:

"The P-47C could carry 425 rounds for each machine gun, but ammunition belts had to be carefully loaded any time more than 275 rounds per gun were to be carried, or stoppages were likely to occur." (p. 47)

At the 1C forum, JG53Frankyboy posted:

please:
give the P-47D-22 the same flightmodel/performance as the P-47D-27.

so they can be used side by side - as in real.
the P-47D-10 can still "represent" an early Razorback Thunderbolt with its actual FM version 4.08

I'm not sure if side-by-side operations is proof that they were equal; I saw a P-51D fly along with an F-16 at an airshow this summer which only proves that they can match speeds, not that they are equal in ability. With the P-47 'D' series, the -22 and -27 blocks had more differences between them than just the shape of the rear fuselage:

"The next real change came with the P-47D-22-RE which was the first to have the Hamilton-Standard paddleblade propeller installed at the factory. This was the first of three propellers that had blades with a wider chord which offered increased performance over the original Curtiss Electric propeller with blades of a narrow chord. The other two paddleblade propellers were built by Curtiss Electric, one having a symmetrical blade design and the other having a wider asymmetrical shape. These two propellers were first installed on the P-47D-23-RA, which otherwise was the same as the P-47D-22-RE. These two production blocks were also the last razorback Thunderbolts to be built.

"The P-47D-25-RE at Farmingdale and the P-47D-26-RA at Evansville were the first to feature an electrically operated bubble canopy similar to that used on the British Hawker Typhoon...These two production blocks also saw an increase in internal fuel capacity from 305 gallons to 370 gallons to further extend the Thunderbolt's range. There were also changes in the cockpit layout, and the water injection system was increased to thirty gallons.

"The next significant change occurred with the P-47D-30-RE and P-47D-30-RA when compressibility flaps were added..."

(Excerpted from D&S Vol. 54, P-47 Thunderbolt in detail and scale, by Bert Kinzey, 1998.)

Summarized, the P-47D-27 not only had a changed shape but could carry an additional 65 gallons of fuel and 15 gallons of water. AAF Publication 50-5, Training Manual For The Thunderbolt P-47, published March 1945, described 'the new Thunderbolt (D-25)':

"The new Thunderbolt carries more gasoline, double the quantity of water (for war emergency power), and more oxygen than earlier planes. The additions raise the weight about 560 pounds, gives the plane a higher stalling speed. Airspeed must be kept slightly higher." (AAF 50-5, p. 7)

"While flying the D-25 and subsequent series, it is particularly important to maintain a slight back stick pressure during spin recovery. On these late planes, if stick is permitted to get forward of neutral the plane may go into a flat spin. A flat inverted spin is something to avoid. Fortunately, there is only one way to get the P-47 into this condition. That is by exaggerated use of the ailerons while the plane is stalling on its back. This speed is anything less than 120 mph IAS on models prior to the D-25, and 135 mph IAS for the later series." (AAF 50-5, p. 56)

"Always trim for a dive. Because of the sensitivity of the controls, it is always important to have the P-47 properly trimmed before entering into a dive. This is doubly true for the D-25 and subsequent series. These planes are subject to rudder lock during any uncoordinatied movement of controls." (AAF 50-5, p. 69)

The changed tail design of the D-25 and later series required modification: "Cutting down the rear fuselage to accommodate the bubble canopy had led to yaw instability in the aircraft's flight, so the P-47D-40 had a neat dorsal fin extension in the form of a narrow triangle running from the vertical tailplane to the radio aerial. The dorsal fin extension was retrofitted in the field to earlier P-47D bubble-top variants." (Source (http://www.vectorsite.net/avp47.html))

I don't know if the FMs for the the D-22 and D-27 were significantly different, but the evidence suggests that the two blocks did not fly the same. I don't know if comparing the operational charts in Pilot's Fight Operating Instructions AN 01-65BC-1 (P-47RB,-C, -D and -G models up through the D-23 model) and AN 01-65BC-1A (P-47D-25 through D-35 series) would yield a definitive answer on top speed, etc. for the two blocks. The tactical chart linked at the 1C forum suggests to me, however, that the P-47D-22 could achieve a slightly higher top speed than the D-27 block while the training manual I quoted says the D-27 had a higher stall speed because of its greater overall weight.

Cajun76
10-19-2007, 08:59 PM
FWIW, I think he's mostly referring to the -22 lacking the paddle prop.

The bubbletop was slightly slower and could over yaw in slow speed conditions and spin in on landing approach before the fin fillet was added. In game it has already retrofitted.

Skycat_2
10-19-2007, 09:38 PM
The 3-D model for the ingame P-47D-27 does not show a dorsal filet. The same is true for the boosted P-47D model. Maybe the FM assumes that a fin filet was retrofitted, but the visual model does not represent this.

The 3-D model for the ingame D-22 definately has an asymmetrical paddle propeller. FWIW.

dwaindibley
10-19-2007, 09:42 PM
Thanks Skycat looks like some good reading there and a very nice site you linked. Any other P47 books you or anyone else could recommend? I recently read "P47 aces of the US 8th .." by Osprey which was very interesting and have been trying to find a copy of Thunderbolt! (authors name escapes me at the moment).

TgD Thunderbolt56 I love the picture in your sig btw. Looks like that 190 is in for a nasty shock if it thinks it'll out run the Jug!!

Cajun I'll try those convergence settings you are using thanks

Cajun76
10-19-2007, 09:48 PM
Robert S. Johnson

dwaindibley
10-19-2007, 09:50 PM
Yes that's the one. Ordered it at amazon but was bounced, probably out of print I guess

Skycat_2
10-19-2007, 10:10 PM
"Spitfires, Thunderbolts and Warm Beer" was a good read. It gives a very good insight to what the first American fighter pilots to go to England (first as RAF pilots and then later transfered to the 4th FG, 8th AF) experienced.

I almost picked up "Angels Zero" while I was at the Air Force Museum last week, but the price of hardcover dissuaded me. It's a Thunderbolt pilot's memoir of action over Europe, especially the low-level work. I took a look for it on Amazon.com and that lead me to the book I'm currently reading:

An Ace Of The Eigth: An American Fighter Pilot's Air War in Europe by Norman "Bud" Fortier (Presidio Press, 2003).

The book is narrative memoir of the author's combat experiences in Thunderbolts and Mustangs. I got it as a paperback for $7, new.

Cajun76
10-19-2007, 11:00 PM
Originally posted by Skycat_2:
The 3-D model for the ingame P-47D-27 does not show a dorsal filet. The same is true for the boosted P-47D model. Maybe the FM assumes that a fin filet was retrofitted, but the visual model does not represent this.

The 3-D model for the ingame D-22 definately has an asymmetrical paddle propeller. FWIW.

IIRC, the fillet FM is modeled, but they said they wouldn't change the 3D model to fix it. Been several years, so I could well be wrong.

As for the paddle prop, it's modeled in 3D but the FM dosen't reflect it, AFAIK. I believe Frankyboy has done some testing... and IL2 Compare shows identical performance for the -10 and -22.

Skycat_2
10-19-2007, 11:44 PM
Ahh, I understand now. Thanks for the clarification.

dwaindibley
10-20-2007, 01:58 AM
Originally posted by Cajun76:
My personal setting is 300 for MG and 250 for "cannon". I believe it was Blutarski that did an analysis of the the dispersion vs convergence and determined that 250 to 300 was optimal.

Tried those settings and yes have been merrily shredding enemy aircraft def more punch thanks.

"Spitfires, Thunderbolts and Warm Beer" and "An Ace Of The Eigth: An American Fighter Pilot's Air War in Europe" both on order should give me some happy reading thanks Skycat.

I have to say this is a very helpful forum.

DD

Cajun76
10-20-2007, 08:25 AM
We're always glad to help. Pretty strong community even after 6+ years. We appreciate honest questions like yours rather than the ranters that pop up from time to time just to complain.