Manoeuvre rating for WW2 aircraft

[Garyt]

Hi, New to the forum.

I've been looking at playing a pacific theatre naval/aviation game, looking at possibly Seekrieg, Command at Sea or Seas of War.

I usually apply some houserules to most games I play , and was not quite happy with how these games represent aircraft.

For Instance, Seekrieg uses a multiple of the planes weight for damage resistance, and a rather undetailed method of maneuverability, basically the speed at which a plane can make a 2g turn.

I've looked at some different ways of rating the planes.

Now the weight = damage resistance seemed a bit overly simplistic to me, but looking at it, most things that added weight on a plane improved damage resistance, such as armour and self sealing fuel tanks. I've thought of making a slight change, basing it more on the square root of weight, but also applying an adjustment, probably for self sealing fuel tanks, armor, and other important factors (maybe +/-10-20%). This adjustment would be applied prior to taking the square root.

The maneuver issue is a far tougher one. I look at as ww2 planes both performed in a dogfight capacity, also in a "zoom and boom" one. I take the average of their capacity in both, as the important thing is which plane will win out and force the other to fight to their own strengths.

I took the scores of planes in a few areas and set up the base, and increased or decreased the base score by one per half step of standard deviation from the norm. After 2 half step deviations in either direction, I went to full step deviations.

The attributes I used were as follows:

Dogfight: 3x 360 degree turn time + 1x 200-250 mph acceleration + 2x roll speed at 150mph + 1x roll speed at 250 + 2x acceleration 150-250

Boom and Zoom: 1x Max speed + 1x 200-250 acceleration + 1x 1-5k climb time + 1x 5-10k climb time + 1x Roll at 250 mph + 2x roll at 350 mph + 3x average dive speed 10-5k and 5-1k + 1x acceleration 150-250 mph

Averages of both were used, then the dogfight and boom and zoom scores were averaged.

Here are some results:

P38L- 8.6
Fw190D9- 8.4
P38J- 8.3
SpitIX- 8.2
Fw190D9- 8.1
F4U Corsair-8.0
Bf 109K4 7.9
SpitV -7.9
Ki84 Frank- 7.9
Bf 109F4- 7.8
Fw190A8- 7.8
P51D- 7.7
Bf 109G6- 7.7
Fw190A4 7.6
F6F Hellcat-7.5
SpitIa - 7.4
P39D- 7.2
Bf 109E4- 7.0
A6M5 Zero- 6.9
A6M3 Zero- 6.8
Ki43 Oscar- 6.8
Bf 109G6R6-6.8
P38F TBolt- 6.8
FM2 Wildcat-6.5
P40E- 6.3
P47D-6.0
HurriIIc- 5.9
A6M2 Zero- 5.7
Bf 110C4- 5.7
Bf 110G2R3-5.7
HurriI- 5.4
F4F Wildcat 5.1

What really suprised me - the P-38. The late model P-38 seems a very fine plane. My guess it had fallen a bit out of favor do to the problems the earlier modles had, and the US was more geared towards the P51 by this point.

The ME 109 also suprised me a lot, I guess it should not have, this plane registered I think more Ww2 killls than any other. It's a great climber, a strong vertical/energy fighter, and actually turns well for a plane that fights as well as it does in the vertical, probably due to small size. It's only real drawbacks I know of - it's a bit small, which will hurt it for damage taken, and apparently while it could dive fast, it was not as maneuverable in the dive as others. This is somewhat represented by bad roll speeds at 350k+, I'm not sure if it truly shows the drawbacks though.

The Wildcat F4 also suprised be in a bad way. But it turns and dives OK, and is below average to terrible on everything else, seems like it was way underpowered. I guess it's durability which is not represented here was it's greatest feature.

Bear in mind also that this is only maneuver (I use the term broadly as it represents both turning and vertical/energy maneuverability), two other separate areas are damage resistance and firepower.

BTW - Firepower as done in Seekrieg uses this formula -
.30 calibre- 1.25
.50 calibre- 2.50
20mm - 8.5
(it does not address the 30mm weapon)

A bit simplistic too I think, the rate of fire while similar on many of the various types of weapons could vary as well as muzzle velocity. The 20mm used by early Zero's had a lower muzzle velocity than the later ones, which also gave it different ballisitcs then the 7.7mm used by the Zero's.

But I alwys thought as a real rough way of thinking that the 2-20mm + 2 -.30 cal was roughly similar in firepower to the 6- 50's used by US planes. According to the above, 19.5 is the rating for the twin 20's, 15 for the 6 50's.

I'm curious as to thoughts on the maneuver formula, personally I think I may have made roll rate a bit too important, and any other thoughts on this.

 

[davebender]

Roll becomes more important as speed increases. At speeds greater then 400 mph roll rate is probably more important then banked turn ability. So the importance of this characteristic is directly related to aircraft max speed.

 

[GregP]

Where did you get the turn time and acceleration data for all these planes? Just curious.

The P-38 was the fastest-accelerating plane in US service.

 

[tomo pauk]

Hello, Garyt,
Congratulations for your effort. I have some questions:
Maybe you would like also to post a table with roll rates, speeds, dive speeds etc? Are the max speeds the absolute maximums, or they hold true for single altitude? Stating the sources should help, too. When you say "1-5k", is the "k" a kilometer, or a thousand feet?
BTW, the "P38F TBolt" is a typo?

 

[Garyt]

Well, I thought the source was real good initially. It turns out it comes from one of the programmers for Warbirds and represents the performance of planes in the warbirds simulator. Information is here:

Home Page

So I can't say the is a result of exhaustive testing of ww2 planes - it's more a copy of someone else's research. It does however seem rather accurate, I'm just wondering if there is perhaps some bias one way or the other.

I must say though it seems to be very rooted in factual information, so it's probably very accurate.

"Where did you get the turn time and acceleration data for all these planes? Just curious.

The P-38 was the fastest-accelerating plane in US service."

There are a lot of factors in calculating the best accelerator with the above stats, altitude is an issue, accelerating from what speed to what speed is another. The Hellcat wins accelerating from 150-250, and the Corsair and Mustang are right behind the P-38 at this lower speed. On Higher end acceleration, the P-38 wins, the Mustang not too far behind. These are the two later model P-38's though, the P38F is unremarkable in this regard.

I'm suprised we did not see more of the late model P-38's, though if this is accurate Price of WW2 Aircraft | C Strohmeyer's Weblog; Life, Business it would seem that you could build about 2 P-51's for the price of a P-38.

For other competitors, the KI-84 (Frank) is one of the best at accelerating, the up-engined ME109's are very good. The FW's are got, not great at accelerating until you get to the Dora. The Me109K4 was a pretty amazing plane considering it's frame was in service at the start of the war, it was the best climber and had great acceleration, better than the Allied planes. I guess that's what happens when you put 2000 horsepower on a small airframe. Apparently they had a lot of internal changes and aerodynamic improvements on this model as well.

"Maybe you would like also to post a table with roll rates, speeds, dive speeds etc? Are the max speeds the absolute maximums, or they hold true for single altitude? Stating the sources should help, too. When you say "1-5k", is the "k" a kilometer, or a thousand feet?
BTW, the "P38F TBolt" is a typo?"

Yeah, P-38F Thunderbolt should be "P38-F Lightning". 1-5K means 1-5 thousand feet. For the scope of what I am doing for a game, it does not make sense to break apart the stats as to what plane is better at what altitude, but to use more of an average instead. I've posted a link to the table.

And I also must say be careful looking at some testing by the US of non allied planes. I know some of the testing was done with Japanese planes that had not been maintained and probably suffered from some "dealer rot". Also, many of these Japanese planes had been run on whatever possibly low octane fuel they could find that had some semblance of AVGAS. Probably fouled these engines some and lowered their overall performance unless they were given rather extensive tune-ups.

One thing I noticed as well - Initially, the P-51 ranked middle of the road even though many of it's numbers were similar to the Dora (even turns a bit better than the Dora). I looked at the P51 to check my math, and found out the math was correct, but the P-51 seemed to be at just the wrong end of the standard deviation breakdown most of the time. I.E. if a 360 turn rating was 20.1-22.1 for a score of 5, the P-51 would be a 22.2 for a score of 4. I gave it "half points" when re-doing it's ratings, but what I really need to do is to come up with a system with less break points, and instead of using 1/2 standard deviation steps make it more in the range of 1/10 steps of a standard deviation.


Overall I must say though that the table looks very similar to anything I have seen from true testing. I think there might be a discrepancy in the P-47's dive time, that's all I really see. The maximum speeds may not match exactly with absolute top tested speeds, they are a hair slower, but they seem to be accurate from a relativity standpoint. And these lower speeds may be more relevant for field performance. Whoever came up with these tables did their research well, even though they may have fudged a few numbers due to lack of data.

 

[tomo pauk]

My 2 cents worth (while acknowledging the work behind the data at the Hoof's site):
-the maneuverability posted, both here and at Hoof's site, is derived from in-game fight models - sort of such a disclaimer should've been posted 1st
-some of the data is questionable (WER for F4F and Ju-88, dive speeds of 460 mph for Zero, Hayabusa, Wildcat, zoom climbs starting from 400 mph for those 3 fighters)
-it is too bad only the data for altitudes under 10000 ft is taken into account
-there is no distinction between different engine regimes (how good/bad the engine power is modeled in the sim, is the engine power listed as take-off power, or WER, or military, what power levels are used in acquiring the data)

 

[davebender]

P-51 ranked middle of the road even though many of it's numbers were similar to the Dora (even turns a bit better than the Dora).

P-51 and Fw-190D9 are late war aircraft with speeds in excess of 400mph. Roll is what counts most for high speed maneuverability and Fw-190D9 was a roll champion.

 

[GregP]

Part of the problem with things like this is primary, accurate data. Many times you'll see something like a P-51 and a SPitfire compared ... but if you read the test conditions, one or the other is limited to some arbitrary manifold pressure or RPM while the other is free to use 20 inches more. Naturally, the one with the higher limit climbs better and is faster. So you HAVE to pay attention to the test conditions.

In the CBI the AVG flew some P-40's that were limited to 59 inches of MAP by the book, but we have had several former AVG pilots including General Davey Allison (no relation to the engine people) say he frequently flew them at 75 inches of MAP to get an advantage or make a sale. The devil is in the details.

I've been trying very hard to compile such a chart for more than 10 years and have a pretty decent start at it, but getting the data on the major types from around the globe is very difficult.

 

[wmaxt]

Greg,

I found a page from CC Jordon that placed the P-38 at 2.8 mph/second, F4U4 at 2.4 mph/sec, and the P-51 at 2.2mph/sec.
I've seen other data that also confirms the assessment by gregt as the fastest fighter acceleration wise.

Bill.

 

[Garyt]

"-the maneuverability posted, both here and at Hoof's site, is derived from in-game fight models - sort of such a disclaimer should've been posted 1st"

Was initially unaware that this was not primary source data. Came to the realization when it seemed to good to be true that ALL that data was right there on all the planes - and all other research I've done you get a smattering of info on a few planes. I did however in a later post state that it appeared the data was from a game.

"some of the data is questionable (WER for F4F and Ju-88, dive speeds of 460 mph for Zero, Hayabusa, Wildcat, zoom climbs starting from 400 mph for those 3 fighters)"

I've heard of but have seen no specs on the zero's limited diving ability - a "not to exceed" speed due to it's fragile construction.



"I've been trying very hard to compile such a chart for more than 10 years and have a pretty decent start at it, but getting the data on the major types from around the globe is very difficult."

Would be very interested in what you have, Greg.

 

[Jabberwocky]

"-the maneuverability posted, both here and at Hoof's site, is derived from in-game fight models - sort of such a disclaimer should've been posted 1st"

Was initially unaware that this was not primary source data. Came to the realization when it seemed to good to be true that ALL that data was right there on all the planes - and all other research I've done you get a smattering of info on a few planes. I did however in a later post state that it appeared the data was from a game.

"some of the data is questionable (WER for F4F and Ju-88, dive speeds of 460 mph for Zero, Hayabusa, Wildcat, zoom climbs starting from 400 mph for those 3 fighters)"

I've heard of but have seen no specs on the zero's limited diving ability - a "not to exceed" speed due to it's fragile construction.

"I've been trying very hard to compile such a chart for more than 10 years and have a pretty decent start at it, but getting the data on the major types from around the globe is very difficult."

Would be very interested in what you have, Greg.

The Zero did not have a "fragile construction". Dive limits were imposed due to stressed skin weakness, not structural weakness. Without significant structural change to the wing, the limiting dive speed went from 390 mph in the A6M2 to 410 mph in the A6M3 to 450 mph in the A6M5. G limit was around 8.8 g.

 

[Francis marliere]

Gary,

as a player of Seekrieg and Command at Sea, I understand that you are not happy with the air-to-air combat rules of these games and try to make out your own model. However, I fear that you open a can of worms and suggest that you look after rules that are "good enough" rather than "good". These games, especially SK are naval wargames and will not simulate accurately air combat. CaS can work fine for large operations in which some aircraft are involved (such as carrier battles) but I am afraid that SK is not designed for this kind of scenarios (SK5 is perfect however for small scale surface battles). Moreover, air combat is complex and almost impossible to simulate. As the proverb says "what can be counted does not always count and what counts cannot always be counted". The most important parameters (pilot quality, tactics, tactical situation, etc.) are difficult to count, and the things that are easier to count (aircraft speed, climb rate, etc.) are not the most important.

IMHO it is usually easier to keep the existing rules and make them better by changing a few things rather than to change the whole rules. Sometimes the game system is coherent and a change in an area has a impact in other fields. A game such as CaS has a strong support (websites, discussion group and official review) and if you use completly different rules, you won't be able to profit from the advices, rules improvements, game aids provided by the authors of the game or the community. In the other hand, if you only change what you don't like in the official rules, you may benefit from this stuff.

As far as I renember CaS, there were two things wrong with the air-to-air rules. The maneuver rating lacks (in 0.5 increment) and should be more precise to make the difference between planes (ie Hurricane I II have a maneuver rating of 2.5 despite the mk.II being better in real word). Moreover some ratings are sometimes discutable and may be changed (3.5 may be a bit strong for the Zero for exemple).

More important, the model that calculates if a plane is destroyed when he is hit, is IMHO inaccurate. Damage value has very little impact in the game and the chances of destruction depend only of gun power. If hit by the same gun battery, a Zero and a Corsair have almost the same chances to go down.

I will finish by pointing out that your sources are very accurate but not very reliable : it's data from a game not historical data. A while ago, I tried to use this website as a source while working on my own air-to-air rules for CaS. I found some big differences with historical data. I now rather use other sources, such as :
WWII Aircraft Performance
Standard Aircraft Characteristics Arcive
Historical Information
Note that, as good as this sites are, they don't provide all the stuff that you would like to have. Some data such as acceleration, dive speed, roll rate is very difficult to find and I am afraid you won't find them for all the planes that interest you. Unfortunately, you have to work with what you have at hand.

Best regards,

 

[tomo pauk]

Hello, Garyt,

Was initially unaware that this was not primary source data. Came to the realization when it seemed to good to be true that ALL that data was right there on all the planes - and all other research I've done you get a smattering of info on a few planes. I did however in a later post state that it appeared the data was from a game.

Please do not feel offended in any way. I've already congratulated you on your work, and acknowledged the effort both from you and Hoof.
However: I'm not aware of your independent research (ie. other than it uses Hoof's data), quality of it, nor of the results of it. The source of yours has two major shortcomings: it's data comes from a person doing measures in a simulation, and any simulation is, at the best, a tertiary source. I did not "get a smattering info on a few planes", but simply pointed out that your source got several things wrong, without any deeper look at all of the other data. The another thing with Hoof's data is that it uses/relies on data available almost 20 years ago (the page was last updated on October 1997), ie. it does not take into account all the research done in last 2 decades.

I've heard of but have seen no specs on the zero's limited diving ability - a "not to exceed" speed due to it's fragile construction.

Jabberwocky's replied to this - the dive abilities between different marks of Zero were much more different historically, than at Warbirds. And the in-game models do dive much better than it was historically so.

 

[GregP]

Hi Wmaxt!

I've seen those acceleration ratings, too, but have not come across the flight reports with primary data in them.

The P-38 went from the non-combat ready models before the F model to the F model and beyond with G, J, and L. I can't believe they all accelerate the same and I especially don't believe they accelerate at a constant rate. Perhaps the ratings above are an average from cruise speed until some arbitrary speed, say ... 350 mph, is reached. Without the data I don't know what models were being flown, the rpm and manifold pressure they were using, the weight of the aircraft during the flight, or anything else. They went from early Allisons to the late-war -100 series units that were different animals from the early units.

The Corsair went from types very similar to one another (F4U, F4U-1A, F4U-1D) to types well in advance of them (F4U-4 and later) and from less than 2,000 HP to 2,250 HP and more later. Speed went from just over 400 mph to about 470 mph in the Corsair.

The P-51 went from the Allison-powered early models to the 2-stage Merlin units and even better in the P-51H.

So the real questions would indlude which models were test at what weight, altitudes, and power settings, and how exactly the quoted numbers were derived since I find it unbelievcable taht the acceleration was a constant regardless of starting speed or altitude. The P-38 had Allisons, the F4U had an R-2800, and the P-51 had both the Allison and the Merlin.

It is quite possible the numbers are at the particular type's best altitude and are averages from lo, say,w cruise to some combat speed of choice that may well vary with the type. I know you have thought of most of this and my text above is nothign new, but getting accurate primary data is , as I said, yough since it is time-sensitive data. As we all know, a Bf 109D is quite a different animal from a Bf 109K. The same can be said for MOST of the fighters of WWII. Even the Grumman Bearcat, which DID make WWII but didn't make combat has different performance in its very low number of variants.

Getting these data for US types is difficult but some can be found. Getting these data for British types can also be done for at least some of the fighters. Getting these data for German types is fraught with danger since so many people claim to have the flight test reports and so many of them disagree with one another.

Finding primary source data on Japanese types is almost impossible, though you CAN find some. I happen to have a rather pritine copy of the 2-book set entitled ""General View of Japanese Military Aircraft in the Pacific War" compiled by the staff of "Airview" by Kanto--Sha Co, Limited in Tokyo in 1953 (English text in 1955). The entire staff was Japanese and the editor in chief was Kazuo Baba. The cutaways draings were by Kikuo Hashimoto. The preface staes that they used only authentic Japanese records and were as accurate as they could be in the 1953 timeframe. The primary intent was to produce a factual reference, not a political text.

It has a fairly comprehensive table with data on 54 Japanese Army types and 68 Navy types as documented in Japanese service or flight test. But making coparisons is almost impossible since the data are simple data points. There is nothing like a chart by altitude for various performance numbers duch as top speed, climb rate, and rate of turn. The primary performance data points are Vmax, Vland, Climb (time to height), range, and celiling with no reference to Vmax at sea level plus Vmax at best height.

To date, I have found no better reference for Japanese types, and that makes a flight model very difficult and meaningful comparisons pretty tough.

 

[Garyt]

"as a player of Seekrieg and Command at Sea, I understand that you are not happy with the air-to-air combat rules of these games and try to make out your own model. However, I fear that you open a can of worms and suggest that you look after rules that are "good enough" rather than "good"."

Well, in actuality that's pretty much what I am doing, looking for the "good enough". Some times the games seem biased in one way or another - such as the 3.5 for the Zero. While it's turning abilities merit this, there are other aspects of it's overall performance that do not. But I'm not looking to do a complete re-write - more of changing the rules a bit for accuracy. Maybe going to a D20 vs a D10 for maneuver rolls, etc.

Francis - Have you had a chance to look at Seas of War? Seas of War

It's a bit more Seekrieg than Command at Sea. Looking at that as a possibility as well. I'm looking to play a Flat-Top ruled game for strategic purposes, but tactical using one of the above mentioned games.

What's neat about Seekrieg regarding Naval aviation - they have rules for planes returning early from a sortie without accomplishing a strike, being miles off target, etc. etc. Real life things that prevent a strike of say 40 planes really indeed striking as 40 planes.

Regarding your thoughts about being careful with changing rules - I get that. For instance, with seakrieg depending upon weather you could have easily 20%+ of a strike force not make it to the target. In many boardgames, this is abstracted into a lower effectiveness from the whole strike. To accurately represent this in something modeled more specifically like a miniature game, you have to account for those planes that do not make the strike, as individual planes will be more effective.

 

[drgondog]

The P-51B would out perform the D in every category except firepower and visibility.

 

[Garyt]

"The P-51B would out perform the D in every category except firepower and visibility."

Not from what I have seen. In about any source they seem to be very similar with a few differences. seems the Dora was a better roller, not from hoof's data but from other data, even posts on this site. P51 was better at turning.

 

[fastmongrel]

"The P-51B would out perform the D in every category except firepower and visibility."

Not from what I have seen. In about any source they seem to be very similar with a few differences. seems the Dora was a better roller, not from hoof's data but from other data, even posts on this site. P51 was better at turning.

I think dragondog is comparing the Mustang P51B against the later P51D model. When you say Dora do you mean the Fw190D.

 

[drgondog]

"The P-51B would out perform the D in every category except firepower and visibility."

Not from what I have seen. In about any source they seem to be very similar with a few differences. seems the Dora was a better roller, not from hoof's data but from other data, even posts on this site. P51 was better at turning.

I was referring to the P-51B vs P-51D

The P-51B-7 (mid block) and beyond had Exactly the same engine as the P-51D _____> 1650-7. At most altitudes the P-51B-1, -5 and early -7 had the 1650-3 engine with better performance at high altitude than with the 1650-7. Last and most important the P-51B/C with 4x.50 cal versus 6x .50 cal was ` 275 pounds lighter than any version of the P-51D.

Same wing, same ailerons ------------> roll slightly better, turn slightly tighter, accelerate slightly better, and climb slightly better with same fuel and throttle settings.

Versus the FW 190D-9 the D-9 could out roll any Allied fighter and was otherwise evenly matched in most cases against the P-51. Perhaps the 51 could out turn the FW 190 slightly and with 150 Octane fuel probably out climb the 190D..

 

[Garyt]

I was referring to the P-51B vs P-51D

Gotcha.

Versus the FW 190D-9 the D-9 could out roll any Allied fighter and was otherwise evenly matched in most cases against the P-51. Perhaps the 51 could out turn the FW 190 slightly and with 150 Octane fuel probably out climb the 190D..

Pretty much what I have read as well.

A little bit Ironic to me that the Mustang, which is best at high altitudes rolls worse but turns a bit better than the Dora. You'd think this would be reversed, as the high altitude plane would lend itself more to boom and zoom tactics.

Neither though seem to have been very efficient turners.