"Scraps of Paper - in a World on Fire" Scenario 127

[Dili]

Yes i'll be trying with B-26, still do not understand the logic behind why it works with your settings.

[Admiral DadMan]

ORIGINAL: Dili

Yes i'll be trying with B-26, still do not understand the logic behind why it works with your settings.

This is probably confirmation bias, so take this with some skepticism.

Alfred suggested that there may be an issue with drop tanks that are mounted on the Center Line at the same time as torpedoes. I can confirm that drop tanks on the Center Line will prevent Center Line mounted torpedoes from being used.

Someone else (I think it was Big B) suggested that the weapon used for torp replacement (filter 4) should be combined with another mission, most likely a Port Attack (filter 16). This makes sense, as ships can be attacked in port. So on Normal Range with a torpedo in the mix, there should be a weapon with a filter 20 (4+16), so that if torps are not chosen or are not available on a Naval Attack, it will take this weapon instead.

For an Extended Range mission without a torpedo specified (as in my above TBD example), don't use filter 4 because you don't need an alternate for the Primary Naval Attack weapon. The weapon used for Naval attack (filter 2) will also be used for Port Attack (filter 16). This weapon should have a filter of 18 (2+16).

[Admiral DadMan]

Caveat: I have not tested this with Japanese torpedoes. IJN torpedo planes have a hard coded 800kg AP bomb that can appear during a Port Attack. I have not done any testing on Japanese aircraft.

[Dili]

Yes it is an hypothesis but i think someone also tried with level bombers and those typically don't have an external centreline tank. Did you tried this with level bombers or only with TB's?

[Admiral DadMan]

I have tested with TB's and DB's (in which I installed a torpedo [:D]) and I am getting the results I expect and desire.

I believe (before I test more) that if you handle the torpedo replacement properly, the other weapons/filters/devices will work as you wish regardless of aircraft type.

ORIGINAL: Dili

Yes it is an hypothesis but i think someone also tried with level bombers and those typically don't have an external centreline tank. Did you tried this with level bombers or only with TB's?

[btd64]

RHS has B-26's with torpedoes. And they work....GP

[Admiral DadMan]

ORIGINAL: btd64

RHS has B-26's with torpedoes. And they work....GP

Got a link so that I can download it? (please [;)])

[btd64]

Babysitting at the moment. I'll send you the files via email later....GP

[Dili]

ORIGINAL: btd64

RHS has B-26's with torpedoes. And they work....GP

RHS has aircraft wps filters?

[Admiral DadMan]

ORIGINAL: btd64

Babysitting at the moment. I'll send you the files via email later....GP

Gracias.

[Admiral DadMan]

Level Bombers:

Morning Air attack on TF, near Catbalogan at 85,84
Weather in hex: Partial cloud
Raid spotted at 26 NM, estimated altitude 17,000 feet.
Estimated time to target is 6 minutes
Allied aircraft
B-17D Fortress x 7
Allied aircraft losses
B-17D Fortress: 5 damage
Japanese Ships
CVL Ryujo
DD Natsushio
Aircraft Attacking:
7 x B-17D Fortress launching torpedoes at 200 feet
Naval Attack: 4 x 22in Mk13 AerTorp
Carrier support unable to supply air cover...

-------------------------------------------------------
Afternoon Air attack on TF, near Batan Island at 85,70
Weather in hex: Overcast
Raid spotted at 4 NM, estimated altitude 19,000 feet.
Estimated time to target is 0 minutes
Allied aircraft
B-17D Fortress x 5
Allied aircraft losses
B-17D Fortress: 2 damaged
Japanese Ships
xAKL Kumakawa Maru
xAKL Hanakawa Maru, Torpedo hits 3
Aircraft Attacking:
5 x B-17D Fortress launching torpedoes at 200 feet
Naval Attack: 4 x 22in Mk13 AerTorp

[Dili]

Thanks, works then, not dropping bombs and torpedoes at same time anymore.

[Admiral DadMan]

All Scenario files, Art, and the back story can be found here on Dropbox.

What's New:

*Sorted out proper loadouts for Allied Torpedo bombers to substitute the proper ordinance for Ground/Port/Airfield/City Attack or replace torpedo on Naval Attack.
---This is not fully completed yet, as there is considerable work to do on all Allied aircraft. This will be followed by a possible rework of Japanese aircraft.

*Returned Yorktown and Enterprise to 19,900 ton design as historically built.
*Returned Wasp to 14,500 ton design as orginally built
*Moved Hornet to the Wasp class so that she would conform to Treaty tonnage limit.
*US carrier arrivals tweaked to balance out force levels.

US Carrier Deployment
CVB-Langley -(Apr42 fitting out after re-construction)
CV-Lexington -(In theater)
CV-Saratoga -(San Diego fitting out)
CVL-Ranger -(Norfolk, East Coast)
CV-Yorktown -(Norfolk, East Coast)
CV-Enterprise -(In theater)
CVL-Wasp -(June42)
CV-Hornet -(June42)

*Reset US CV aircraft capacities and air group sizes to conform to USN early war doctrine. Carrier capacities and air groups will grow as practices changed and doctrine evolved in the first year.

Lexington/Yorktown class:
Dec41 =69
Jan42 =72
Mar42 =78
Jun42 =88
May43 =90

Ranger:
Dec41 =69
Jan42 =72
Jun42 =78

Wasp class is not affected by this.

Langley CVB class
Apr42 =88
Jun42 =90
Mar43 =102

Added two new aircraft to the game:
*Consolidated TBY Sea Wolf carrier-based torpedo bomber. Was developed as a replacement for the TBF/TBM Avenger.
*Douglas BTD Destroyer carrier-based attack bomber. Was developed as a replacement or the SBD Dauntless, SB2C Helldiver, and could carry a torpedo.
---Both of these aircraft become available in September 1944.

Those are the major changes.

Click here to go to the first post for scenario information.

[Admiral DadMan]

What I'm working on for v0.4:

-Re-introduction of Shinano (and a scrapped sister ship) as the improved Yamato class originally planned and laid down.*

Most notably, armor will be 10–20 millimeters thinner than that of Yamato/Musashi, as their armor thickness had been proven to be greater than it needed to be for the desired level of protection. That weight savings was put into improved protection in other areas.

These two ships will mount the superior Type 98 dual purpose 100mm/65cal in place of Yamato's Type 98 dual purpose 127mm/40cal AA weapons.

*(Garzke, William H. & Dulin, Robert O. (1985). Battleships: Axis and Neutral Battleships in World War II. Annapolis, Maryland: Naval Institute Press. ISBN 978-0-87021-101-0.)

There will be the opportunity to build out these two ships as battleships or carriers after they arrive.

-I am also researching the possibility for the Mogami class to be converted into full-blown CVL's

Further along the development track:

*Mission-defined weapon loadouts for Allied Aircraft
*Mission-defined weapon loadouts for Axis Aircraft.

As always, observations are welcome.

[Admiral DadMan]

I've done all the editing I think that I'm going to do on this scenario.

Shinano can arrive in late 1942. She and her sister (Shinano II) can be finished as a battleship, converted to a carrier at a properly sized repair shipyard. Conversely, as the Japanese have this ability, they can be halted before they arrive.

The two Ibuki class cruisers (Ibuki, Ibuki II) can also be either halted, or built as CA's or CVL's.

Beginning April 1942, the Mogami class can be converted to CVL's at a properly sized repair shipyard.

Many (not all) Allied torpedo-carrying aircraft have had their loadouts re-programmed for specific types of targets. Many aircraft that historically performed ASW work now carry a 250lb "depth bomb" as their ASW load.

I decided to leave well enough alone on the Japanese side.

In addition to the Vought TBU/Consolitdated TBY and Douglass BTD, another plane appears.

It is a carrier-based variant of the North American P-51D Mustang that was fitted with a tail hook and tested on USS Shangri-La in late-1944 called the F1J-1 Seahorse.



All files can be found in links from the first post.

Happy hunting.

[Admiral DadMan]

Some minor corrections and improved plane art for v1.1.

Navy F1J-1 Seahorse:

[RyanCrierie]

ORIGINAL: Admiral DadMan

It is a carrier-based variant of the North American P-51D Mustang that was fitted with a tail hook and tested on USS Shangri-La in late-1944 called the F1J-1 Seahorse

I have the data on the proposed North American Liquid Cooled VF they proposed to the USN, it was basically a modified version of the P-51H.

[RyanCrierie]

North American NA-133 - Navalized P-51H Mustang

At NARA was a folder on the XF8B and the North American Liquid Cooled VF and my guess as to what the NAA Liquid VF was turned out to be correct. There were no eye popping brochures, but a mass of correspondence back and forth. There was even some Jet VF specifications buried in the correspondence as well (!).

It's quite clear that North American was aiming at the same market that the F8F was being aimed at; since one of the drawings (reproduced in reduced format) was one comparing the NA-133 to the F8F. The other drawing was a much clearer version of the badly degraded mimeograph copy I found at the NHHC's Aviation History Branch.

----------------

COMMENT ON MILITARY REQUIREMENTS COMMENT

1. As stated in letter, Bureau has checked none of the figures quoted by Vought, but even on basis of figures presented, the liquid cooled design is considered to possess "no outstanding advantages". If designs were checked on comparable engine ratings, the liquid cooled design would be inferior in all aspects of performance, as detailed below.

2. Regarding the spot - as pointed out in the letter, a different arrangement of equipment and wing folding was used in the two designs. The liquid cooled design has the guns in the outer panel with ammunition outboard of the 4 guns. The air cooled design shown in the tabulation has the guns in the center section with the ammunition inboard of the 6 guns. By moving the wing fold inboard, and ammunition outboard, a folded span of less than 16.5 feet is obtained without difficulty. Such an arrangement gives a spot of 205 ft. for 36 liquid cooled airplanes, and 202 ft. for 36 air cooled airplanes, or as stated in the letter, substantially identical spots result.

3. Performance and engine - The ratings used for performance and performance figures must be considered together. As shown in the tabulation, the liquid cooled engine design has slightly better speed, (7 mph max.) and better climb (475 fpm max.) through the medium altitudes. Above 23000 ft., the air cooled has a large, speed and climb advantage, giving a higher average V max. and R/C. These figures are based on a liquid cooled Allison engine rated at 2100 BHP. Army power plant personnel have informed Bureau personnel that no such engine is in sight. A comparison of Allison engine present ratings and expected future ratings are shown on the attached sheet. Correcting Vought performance figures back to Army engine ratings will make the air cooled design superior throughout the altitude range. The 2700 BHP rating used for the 2 stage R 2800E engine, is 50 HP more conservative than Bureau estimates. It is considered that the 2100 BHP Allison engine is far more problematical than the 2700 BHP R 2800 E.

4. In view of the greater interest in jet and turbine powered VF types, it was considered unnecessary to attempt a thorough evaluation of the air cooled or liquid cooled designs submitted by Vought. Mil. Req. has concurred in this general conclusion. It is suggested that further liquid cooled vs. air cooled arguments be. held in abeyance pending receipt of North American's proposal, and evaluation of P-51D with arresting hook now at NAMC, Phila.

G. Spangenberg
C. L. Fike

[Written on Paper]

This was in reply to caustic Mil Req comment. the letter was deleted from files at direction of Adm.

----------------

Comment -

This is essentially a P-51 and presumably incorporates improvements based on P-51 experience. While the P-51 did not have entirely adequate directional and longitudinal stability, the e.g. has been moved forward somewhat. We have no means for checking this in the time available but it would appear that the destabilizing effect of 4-blade prop and increased power may offset much of the gain due to forward shift in c.g.

Variable dihedral may turn out to be very effective. It is understood that negligible weight is involved to obtain this feature.

There should be some concern about gas tanks on the wing tips. The weight moment may be quite troublesome at low speeds. There should be some check on flutter effects.

It is not known how the stall will compare with P-51. The stall of the XP-51 was none too good. The lift coefficient developed on the P-51 was rather low.

Diehl 10/28/44

------------------------------

Aer-R-3-LCS
24 July 1944

MEMORANDUM

CONFIDENTIAL

From: Military Requirements.
To: Engineering.

SUBJ: Experimental Carrier Fighter Powered by Liquid Cooled Engine, Request for Proposal.

Ref: (a) DCNO (Air) Conf. memo. Op-31-CL-MML (SC) A21-1, Ser. 053031, dated 21 March 1944.

1. Ref. (a) was routed through the Bureau of Aeronautics for answer and comment. Both ref. (a) and the answer thereto aroused comment which indicated violent disagreement on the part of those concerned. The fact remains that the Mustang outstrips all other VF of its time. The variance of opinion itself expressed by the interested parties indicates an experimental venture in the liquid cooled airplane is necessary.

2. If carriers are to remain a potent force in warfare, then their airplanes must equal or better in performance those of the enemy, regardless of their operating base, To do so, though, it may be necessary to. launch all planes by an auxiliary means in order that their performance be not inferior due to the take off handicap, provided they can land safely on return.

3. It is believed that any carrier fighter designed for use within the coming five year period should have a Vmax of 475 m.p.h. - at a critical altitude of 25,000. Vmax at SL should be at least 425. This plane, in its fighting weight, should climb to 30,000 ft. in five minutes. Its combat radius should be 300 miles in the escort version, 75 miles in the interceptor version. Either version should be able to remain in the air six hours. The present air situation in the Pacific is entirely the result of fighting a fifth rate air power. The problem of protecting a carrier in the near future will be that of meeting an enemy attack force picked up at radar range and coming in at 400 m.p.h. Their missiles will probably be of the homing variety. No longer will slow attack groups circle your task force prior to attack. To stop such an attack, you will not want a fighter that is also a dive bomber, also a ground attack plane, also a long range scout. You will need the best flying machine that can be built or carrier aviation will disappear on the first attack.

4. It is, therefore, requested that a proposal for such a fighter, powered by the appropriate liquid cooled engine, with the performance suggested in paragraph 3 above, be asked for from interested companies. It is particularly desired that North American be asked for such a proposal. The problem itself will indicate the type of take-off necessary to produce the best possible fighter. A parallel proposal using a liquid cooled engine - Jet combination seems in order.

5. The purpose of this proposal is to obtain the smallest aircraft possible for carrier use without loss of range and performance.

R. E. DIXSON
Comdr., U.S.N.

--------------------------

This may be the memo that started it all:

--------------------------------------------------

Op-31-C1-MML
(SC) A21-1

Serial: C53031

21 Mar. 1944

MEMORANDUM

CONFIDENTIAL

From: DCNO (Air)
To: Chief, BuAer

SUBJ: US Navy Aviation Experimental Program - Review of.

1. It is requested that the Aviation experimental program be subjected to a study and review.

2. It Is considered that experiences of the war and the present trend of design within the Navy may point to the necessity of reefing our sails and. departing on a new tack.

3. The weights and physical measurements of our newer airplanes are increasing rapidly with the result that we shall soon be forced into reduction of carrier complements. To obtain increased performance the natural and logical step has been an increase in power. However, the direct result of this has been larger engines presenting greater frontal areas with correspondingly larger fuselages to accomodate them.

4. Possibly we have reached the place in the development of the air-cooled engine where we should sever our many years of allegiance and look to a design of aircraft incorporating liquid cooled in line power plants.

5. The size and weights of our projected designs is ample evidence of the fact that our engineers must concentrate on smaller and more compact aircraft with which to do the job at hand. If the liquid cooled in line engine represents the step necessary to achieve the results, we should then be spending some of our time and money on development of that article.

J. S. McCain
Deputy Chief of Naval Operations
(Air)

---------------------

Aer-E-213-CS

MEMORANDUM

11/25/44

SUBJ: Model VF Airplane - North American Aviation Model 133, Liquid Cooled Proposal -Summary of.

Refs:

(a) NAA Conf. Ltr. AL-874, dated 20 Oct. 1944•

(b) NAA Conf. Ltr. AL-889, dated 3 Nov. 1944-

(c) DCNO (Air) Conf. Memo. OP31-C1-MML, (SC) A21-1, Serial 053031, dated 21 March 1944.

(d) Mil. Req. Conf. Memo. Aer-R-3-LCS, dated 24 July 1944.

(e) Engr. Conf. Memo. Aer-E-211-GS, VF, dated 21 Aug. 1944.

(f) Mil. Req. Conf. Memo. Aer-R-3-JTB, dated 2 Sept. 1944.

Encls : (HW)

(A) Performance Summary and Comparison, dated 11—22 —44.

(B) VF Speed vs. altitude Comparison, dated 11 —2 2 —44.

(C) VF Climb vs. Altitude Comparison, dated

(D) VF Combat Radius vs. T.O. Dist. Comparison dated 11-24-4-4.

(E) Comparison, NA-133 vs. Mil. Req. Specification, dated 11-22-44.

(F) V-1650-11 Engine Rating Curve Sheet, dated 11-13-44.

1. By refs. (a) and (b), North American Aviation, Inc. has submitted engineering, cost and delivery data on a carrier basedVF airplane powered with a V-1650-11 liquid cooled engine, as Informally requested by the Bureau.

2. The history of this proposal dates back to ref. (c), which requested a review of the aviation experimental program to determine whether carrier based aircraft should be utilizing liquid cooled engines to obtain high performance in smaller' sizes of airplanes. Comments on ref. (c) indicated a wide diversity of opinion on the question, and ultimately resulted in ref. (d) requesting that proposals from various contractors be obtained for a carrier based VF airplane powered with a liquid cooled engine. Ref. (f) provided a clarification of requirements as requested by ref. (e). A number of contractors were requested informally to submit such designs, but North American Aviation was the only company willing to submit a complete proposal. Chance Vought made some preliminary studies in a comprehensive fighter design survey, but reached the conclusion that other types of power plants were more suitable for future fighters. The remaining contractors were unwilling to attempt liquid cooled designs at this time.

3. The North American Model 133 is similar to the P-51H Airplane being procured by the Army. The power plant is a fuel injection, Packard built, Merlin V-1650-11 engine equipped for water injection, and the installation is substantially identical to that of the P-51H. The wing has been redesigned for folding, 10 sq. ft. of area added, slotted flaps incorporated instead of split flaps, and larger ailerons with power boost have been installed. The landing gear has been modified to meet Navy strength requirements. The fuselage fuel tank of the P-51H has been eliminated, and the wing fuel cells capacity reduced to give a total of 150 gal. of protected fuel. Elimination of the fuselage fuel tank reduces the e.g. travel, permitting use of a smaller horizontal tail, while maintaining adequate longitudinal stability. Arresting and catapult provisions are basically similar to those installed on a P-51D, though somewhat improved from a drag standpoint.

4. The interested branches of the Engineering and Maintenance Divisions have examined the data available, and a number of details found which require correction if the design Is to be procured. The discrepancies are not major, and do not affect the performance of the airplane to a sufficient extent to require submission of a revised proposal. Wing tip drop tanks of 50 gal. capacity have been proposed, primarily to better the airplanes spotting characteristics by allowing the tail to pass under the center section of the wing. The nonstandard tanks seriously complicate the fuel system, introduce handling and filling complexities as well as aggravating the logistics problem. Since the spotting advantage of 39 airplanes as compared to 32 airplanes in a 200 ft. deck length exists only when bomb racks and rocket launchers are not installed, it is considered that a standard 100 gal. tank suspended from the wing bomb rack is a superior installation.

5. Performance characteristics of any airplane are proportional to the engine ratings available. In ref. (e), Engineering requested certain data to permit establishment of naval ratings for liquid cooled engines. Military Requirements, in ref. (f), indicated that power plant reliability and fuel type were to be at the contractor's discretion. North American's performance was submitted on 90 inch manifold pressure ratings, using 150 grade fuel and water injection. These ratings are not in agreement with Army, British or Packard data. Two Bureau performance estimates were made, one to check the NAA figures, and the other at the weights estimated by the Bureau, slightly higher than those of NAA, and at the engine ratings given by the Army as their anticipated future ratings. These ratings are shown on End. (F), with the V-1650-3 present rating indicated for comparative purposes only. It will be noted that the normal rating of the engine is less than the R-1820 or R-1830 at sea level, while the W.E.P. rating used by North American approaches that of the R-2800.

6. A summary of performance characteristics for the design Is shown on Encl. (A), while speed,, and climb curves comparing the airplane with the F8F-1, F8F-2 ("E" Engine) and F2G-1 are included as Encls. (B) and (C). The F8F performance shown is the Bureau estimate of the production airplanes with both the present "C" engine and the future "E" engine, while the F2G-1 is shown at the current military rating. Previous comparisons using the "E" engine have been subjected to criticism as a hypothetical engine. The V-1650-11 engine is not scheduled for production until June 1945, and the NAA-133 airplane is not promised until 9 months after date of contract, it therefore appears proper to use the "E" engine in the comparison since current estimates are that it will start in production by 1 Sept. 1945. An experimental F8F-2 should be flying during the spring of 1945. A plot showing combat radius (standard VF problem) spotted against take-off distance is included as Encl. (D).

7. Encl. (E) shows a comparison of the characteristics of the NAA-133 airplane with those specified by Mil-Req. It is obvious that the design fails to meet the desired performance by a wide margin.

8. The most serious disadvantages of the NAA-133 design for carrier use that have been mentioned are:

(a) Increased vulnerability inherent in any liquid cooled arrangement over air cooled types.

(b) Increased maintenance because of addition of radiators and aftercoolers.

(c) The airplane as presented will possess the poor ditching characteristics of the P-51 series airplanes.

(d) Introduction of liquid cooled type will increase logistic problems, and necessitate an additional training program.

9. This memorandum has been prepared to summarize the NAA-133 proposal data for use in the conference now scheduled for 1400, Monday, Nov. 27, 1944.

W. Z. FRISBIE

[RyanCrierie]

Some more pix

[RyanCrierie]

Comparison of estimates