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[Zanadu]

Just got the new download (1 Oct.). Two items.

Under German a/c stats, there is still a blank where the FW190A should be, and there is still an entry labeled FW190A where the '190D should be.

Why doesn't the P38F have the 'trubo' feature, as it DID have a Turbo-supercharger. Even a REAL turbo rather than the two stage mechanical blowers used by the P51, Spitfire and '109K. In fact, of the a/c listed ONLY the P38 (all models except the Lightning I built for the British) and the P47 had actual turbo supercharging.

[Zanadu]

Sorry. Should have said of the 'Fighter a/c listed...' as the B17 and B25 both used turbo superchargers.

[bartbert]

Dan sets all the aircraft statistics, so hopefully he'll post an answer shortly.

[Zanadu]

And for the bombers that should have been B24 not B25. D**n I must be half asleep today.

[Zanadu]

Just played on local. I see you have re-valued the AI a/c. It really seemed silly to have an AI leader valued at 50 with far more skills than one of mine valued at 150.

My leading Zero pilot took a pair of Bettys past a pair of Corsairs with a moderately good leader and a pair of P47s with no skills at all, and took down 644xp.

[Guest Mike]

From chatting with Dan I believe the "turbocharger" ability in DiF does not directly relate to the presence of turbo-or super-charger, so much as it does to teh relative high altitude capabilities of the a/c.

Many a/c had turbochargers, and virtually all had at least 1 stage superchargers.

What does matter is that whichever is used makes a significant differnce to performance at altitude. Many a/c had even 2 stage superchargers that were not sufficient to make them high altitude fighters - eg the Napier Sabre in the Tempest had a 2-stage supercharger, but does not get a turbo in the game.

OTOH the Mig-3 does get a turbocharger despite having only a single speed supercharger IIRC, because its engine was optimised for high altitude operations.

Back to the P-38F - it's turbochargers could not produce the full chatrge theoretically possible, because of the inefficient intercooling system fitted - the air was sent out tubes to the wingtip and back to the engine to cool it - this made them vulnerable to damage, provided little or no control for the intercooling, and didn't do a very good job.

The P-38J was the 1st model to have core-type radiators for intercooling, located under the engine and resulting in the deeper cowling. the increased drag from these was more than compensated for by the increased power from adequate intercooling provided.

So I expect that if more P38's are modeled in the game then the "J" will be the first one with a "turbocharger" in game terms.

See here for a summary of P38's , and an interesting comparison between P38F and P28G at this site.

[Zanadu]

The leading edge air cooling system was certainly one of those things that looked really great on paper, but proved to be much less than ideal in practice. Moreover, eliminating it had only a minor effect on drag, but opened up the wing leading edge for additional fuel tankage.

I've seen the P38F-G info and found it very interesting. The manuevering flaps mentioned on the G were actually retro-fitted to the Fs as well and gave the Lightning the ability to match horizontal turns with anything the Germans had, including the '109.

I also found the info on the P47C trials interesting. The results of climb trials between the P47C, Spitfire IX and P38F showed that while the Spit IX had an solid edge over the P38F in climb up to 10K ft., above that the F was not only equal in climb rate, but actually slightly superior.

[Zanadu]

I would point out, in view of the climb data, that the Spitfire IX does have the 'turbo' special effect, although engine performance of the P38F clearly improves more with increased altitude than that of the MkIX.

It's ability to operate effectively at higher altitudes than the F4Fs and Zeroes, let alone the P40s was one of the major reasons the P38 (starting with the F) was so successful. The core coolers certainly simplified the operational handling of the engine-supercharger system, and improved efficiency as well, but even the pre-J Lightnings had the edge over Corsairs, Hellcats with their mechanical blowers (not as good as the one on the Merlin) at the higher levels.

The only US mechanical supercharger in a class with the RR units on the Merlins and Griffins was the one developed for the R2800 in 1944, and used on the F4U-4 and P61C.

[Guest Mike]

In DiF of course turbo chargers have no effect on climb rate - they only affect power at height - everything climbs and dives at exactly the same rate of 1 band per turn - unless you have cards to play!

I'm not sure where you get an advantaged performance for hte 38F over the Spit IX - the figures on the Spit perf page givehte IX better time climbs to all altitudes than the 38F or G - albeit not by much vs the G -the IX is fully 2 minutes faster to 20,000 feet than the F (5.6 minutes to 7.6).

However there were versions of the IX that were up to a minute faster to 20,000 feet on top of that

The graph on the P38 page shows the P38H as having a much better performance than the IX.

The IX also seems to have a significantly higher ceilling than hte P38 - from 42500-45000 feet at mean combat weight depending on engine, vs a maximum of 40,000 feet for the P38L - as seen on on hte rate of climb and time-to-climb charts that is as high as they go.

The P38F is a bit weak in the game IMO - I said as much a couple of months ago and thought that it could probably be better simulated by just taking the turbocharger off the J.

But the Spit IX does seem to have had the edge on it at altitude according to the figures.

[Sixxkiller]

Ahhhhhhhhhhhhhhhhhh GEEK OUT, duh duh dun na, Le Freak C'est GEEK.. GEEK OUT!

[Zanadu]

I was referring to the site you've quoted, which has a tabulation (titled: PARTIAL CLIMBS AT FULL POWER FROM LEVEL FLIGHT UNDER MAXIMUM CONTINUOUS CRUISING CONDITION ...) comparing climb of the P47C to that of the Spit IX and the P38F. Comparing the last two to each other, the Spit has a good advantage from sl to 10K, but above that the P38 is very slightly better. As climb rate changes are largely the result in variations of available power, it sees to me that this indicates that power available to the P38F with its turbo sc was maintained at least as well as that of the Spitfire.

Besides, after Mage, its fun to argue a point with someone who offers counterarguements instead of just repeating himself and demanding that you agree with him.

[Zanadu]

AS to ceiling of the Spit being higher, wing loading (where the Spit has the advantage) is a major factor there as well as engine power.

[Dan Verssen]

Right, the Turbo Charger ability has more to do with overall performance than the device.

At one point there was talk of having two levels of Turbo Chargers in the game. The first would treat High as Medium, and the second would work like they do now.

[lakespeed]

Dan, in the board game some aircraft can't operate at certain levels (i.e. the P-40B was a no-go at Very High) have you thought of making that a factory in the whole Turbo/Altitude thing?

[Guest Mike]

Originally posted by Zanadu:

I was referring to the site you've quoted, which has a tabulation (titled: PARTIAL CLIMBS AT FULL POWER FROM LEVEL FLIGHT UNDER MAXIMUM CONTINUOUS CRUISING CONDITION ...) comparing climb of the P47C to that of the Spit IX and the P38F.

I can't find that page - what's the URL?

found it - http://www.spitfireperformance.com/p-47/p-47c-8thaf-climb.jpg

OK - a couple of points - these climbs were made at 75% full power, which is maximum cruise, and at a standard speed of 165-170 knots indicated airspeed - they might therefore be regarded as "economical" rates of climb.

The text in the report for which this is an appendix states

c. Appendix B shows the results of these climb trials compared with Spit IX and P-38. Again it must be remembered that this is the table of mean results of the trials made, and not necessarily an absolute indication of the airplane’s climb.

They are therefore not really relevant to combat.

[ October 02, 2006, 03:33 PM: Message edited by: Stalin's Organist ]

[Zanadu]

Stalin

I think that you mis-read the captioning. The climbs were made at FULL power. They were initiated from level flight at cruising throttle (165mph I.A.S.)

[Zanadu]

Looked the stats over again. Problem is that, historically, the P38F and G dominated the South Pacific, but by the game stats, the P38F is pretty much of a dog.

The Hellcat and Corsaid have superior performance and horsepower vs the Fs cannon bonus and a slight advantage in structure. The early Zero is about equal with the 'agility' capability to match the P38Fs strenght of structure. The A6M5 is much superior to the P38F with better performance and better wingman offense vs only the Lightning's stronger structure.

With it's low horsepower rating and without the 'turbo' it's going to do poorly at high altitude, where, historically, it dominated.

[Guest Mike]

Originally posted by Zanadu:

Stalin

I think that you mis-read the captioning. The climbs were made at FULL power. They were initiated from level flight at cruising throttle (165mph I.A.S.)

No - read the text accompanying the graph - the climbs were done at 165-170 mph. I know this is different from the "full power" on hte graph, but "Full power" can mean many things - it can mean full emergency power, full normal power, full cruise power - full power at 6", 9" 18" or 25" (etc) boost...

b. All climbs were started at maximum cruise (75% power) climbing at an indicated speed of 165 – 170 m.p.h. indicated.

(from P47 tactical trials)

"Full power" is not a technical term. "Climbing at and indicated speed of 165-170mph" is a precise technical term and is the only thing you can take from this as an indication of what they were doing.

[Guest Mike]

Originally posted by Zanadu:

With it's low horsepower rating and without the 'turbo' it's going to do poorly at high altitude, where, historically, it dominated.

Like I said - IMO it shuold have had hte same stats as the J sans Turbo & it would have been fine.

[Zanadu]

The climbs would have been at full power, with the IAS controlled by the climb angle. Actually, this should have been at least a minor advantage to the Spitfire, as the Lightning was usually clibed at a higher speed, but shallower angle.

The Lightning (F) could out climb the Zero (A6M2 or 3) in terms of actual rate of climb, but the Zero could climb more steeply. The Lightning still gained altitude faster due to the higher IAS.

[Guest Mike]

Yhey might have been as you say - but the document doesn't say that so it remains only a possibility IMO.

[Zanadu]

Stalin: I've been doing some checking with other sources. The rate of climb numbers are too high to be anything except full throttle climbes. While both the RAF and USAAF generally used 'time to climb' numbers to compare climbing performance, the USN used 'initial rate of climb', that it, the average climb rate in feet per minute to ten thousand feet, for comparisons.

The 'book' value initial climb rates for some USN a/c (from UNITED STATES NAVY AIRCRAFT SINCE 1911 by Swanborough and Bowers) are:

Grumman F4F-4 Wildcat: 1950 feet per minute

Grumman F6F-5 Hellcat: 2980

Grumman F8F-1 Bearcat: 4570

(generally considered the fastest climbing

piston engined production a/c ever built)

Vought F4U-1 Corsair: 2890

Vought F4U-4 Corsair: 3780

IJN A6M3 Zero-32: 4500

IJN A6M5 Zero-52: 3140

The value on the chart for the Spitfire IX: 4348

for the P38F 3489

NOte that the Spit IX isn't much short of the Bearcat's climb rate, while the P38F is somewhat higher than the Hellcat and Corsair, which is consistant with the pilot accounts that I've read.

Also, below 10K, the early Zero could outclimb even the Lightning, but lost climb rate quickly above that height, and was no match for the P38F at higher levels.

[rich12545]

There is no compulsion in religion. Q'ran 2:256

Whosoever will, let him believe, and whosoever will, let him disbelieve. Q'ran 18:29

Unto you your religion, and unto me my religion. Q'ran 109:6

Since Islam is in the process of a worldwide jihad, how come they don't believe their own Q'ran?

Or maybe this isn't the place for my comment or your quotes?

[Guest Mike]

Maybe......

[rich12545]

This is a gaming forum. I'm just as much a customer as anyone else here and I don't appreciate coming on the forum and greeted by muslim propaganda. So how about removing it and I won't make disparaging remarks about Mohammad.