Shipbucket

THAT is why the Langley is skipped. The USN in this AU now has three (German) battlecruisers of its own to convert and a plan to convert them.

I still don't understand why you'd convert a twenty year old run down battlecruiser, let alone a German one that's been a pain to maintain her entire life.
HMS Furious was never an ideal design, but it was acceptable because she was available on the slipway, so she could be finished on a reasonable timescale.
With Derfllinger you'll basically have to take her apart down to the last bolt and reassemble her again. Probably with completely new boilers and turbines since the old ones are bound to be completely knackered by now.

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That which does not kill me has made a grave tactical error

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Source Materiel is always welcome.

Ten year old battlecruiser, when she is converted. (1913 laid down, Cramp and Sons get her in 1919/20 and finish her in 1922.)

USS Langley (USS Jupiter laid down as a collier with a troublesome prototype turbo-electric drive in 1911 and converted in 1920 by the Norfolk Navy Yard into a floating flight deck.) Her sister ship USS Nereus was lost to causes unknown in "The Bermuda Triangle" in 1918.

The Langley, herself, was bombed and sunk near Tjilatjap harbor, about the middle of the south Java coast February 1942. Could not dodge Japanese medium bombers because she was too slow and she turned like a potbellied pig.



The wreck is just shallow enough to dive.

Anyway to resume, the USS Proteus, name ship of the class disappears in 1941 in the same general area as the Nereus. Probably a U-boat got her.

So... Why would one want to stick with a RTL history like that? As shot up as Derfflinger and Lutzow were, they seem to be well built. Lutzow went down due to some bad luck and a design flaw in the forehull. The Derfflinger certainly seems to have had no trouble showing up at Scapa Flow in 1918. On the other hand how do Lion and Princess Royal actually fare mechanically?

And here comes the FLUFF.

PLAN DOG: SYNOPSIS: THE KYUSHU PROBLEM, IT IS BETTER TO GIVE THAN TO RECEIVE.

One of the things about Pearl Harbor that makes it so easy, is that the enemy (the USN) concentrates all the targets into a nice cramped harbor with one channel into and out of it. The Imperial Japanese Navy is another matter. There are two main base clusters in the target sets. One base cluster set is situated on Kyushu. That target set is distributed among three naval bases, one anchorage and two IJN and two IJA airbases in the distribution in 1931. (See map above.). It is not so easy to Port Arthur the Orange Team (the Imperial Japanese navy) in that kind of setup, especially with the projected area defenses in place as indicated.

The biggest problem is air coverage. Those airpower circles show what the Japanese 1931 aviation can actually cover. That includes their excellent Nakajima B1M and B2M with reported ranges of ~ 1200 kilometers. The rough rule of thumb, divide by three to get the combat radius, only works for post 1935 aircraft. For a patroller, pre 1935, the rule is air hours at cruise, then divide the result by 4. The average combat patrol radius for Japanese and American aircraft is about 160 kilometers or 100 statute miles. So guess where Admiral Harry Edward Yarnell (TF 10.1 Actual) has to approach with his fleet to do the dirty deed to Kyushu?

If one guesses about 50 kilometers southeast of Fukue Island, then give oneself a cigar. This is the only seam and gap in the 1931 air defense coverage that protects Kyushu. It also happens to be smack in the middle of the commercial sealanes that cargo ships use to carry oil and foodstuffs from south-east Asia and Dutch Indonesia to southern Japanese ports. Two major Japanese airbases in the Rykuku Islands at Futemna and Kodema (Okinawa), make for further extreme difficulties. Nevertheless. American task forces have gamed this type of operation out as the “Orange Team” against both the Blue Team land-based air, surface fleets and opposing alerted “enemy” aircraft carrier forces in previous wargames. The conclusion the Orange Team gains? Aircraft carriers can approach to within 100 kilometers of an enemy coast and deliver a surprise air raid. The attacker runs the risk of losing many aircraft (about half of the attackers) and up to half of the attacking aircraft carriers can be sunk, but the defender usually suffers twice the losses. If the attacker achieves complete surprise, he can inflict substantial damage and escape almost unscathed. He has to strike and run though. If he hangs around to enjoy the fireworks, he becomes submarine bait. The basis for these conclusions is a series of 1920s exercises begun in 1923 (RTL) to work out the peculiarities of the aircraft carrier as a fleet scout. It turns out (in this AU it is the Lincoln Canal and Pearl Harbor. In the RTL it is the Panama Canal and Pearl Harbor.), that the pesky scouting force commanders in these exercises are more interested in attacking the Lincoln (Nicaragua) Canal and/or the Blue Team ships moored in their harbors. In fact, no less than five times is Pearl Harbor or the Panama Canal bombed. After Admiral Yarnell “sinks” three battleships at their moorings in Fleet Problem 12, Charles Adams, Hoover's navy secretary, who observes the Blue Team fiasco, throws his hands up in disgust and exclaims to Admiral Schofield (Chino Actual), “Why do we even bother with defense at all?”

THE NATURE OF THE (AIR) BEAST.

Japan has two competing (emphasis on the word competing) air forces. The Imperial Japanese Army Air Service (IJAAS) has a circus act based on Imperial German Army WW I practice, which is odd, since the Japanese army air service is taught how to fly by the FRENCH. The IJAAS organization is more or less two squadrons of 9 planes each, a 3 plane reserve section and a 3 plane headquarters element; 24 planes in total. Two squadrons form an air battalion, (50-54 planes) two battalions form a regiment (100-120 planes); two or more regiments form a division (200-250 planes, depending on types) and two or more divisions form an air corps. (~500 aircraft) The IJAAS has two of them, air corps that is. One (~600 aircraft) is in China fighting the Mukden Incident, and the other corps (training force of ~450 machines) is in Japan, where it ostensibly provides part of the home islands defense. This is good news for the USN. IJAAS pilots in Japan are mostly trained for close air support with the IJA fighting in China. They have second rate machines for a training establishment and a military mindset totally unsuited for naval warfare or for strategic air defense. They are trench strafers. The Imperial Japanese Naval Air Service (IJNAS) considers them useless and so treats the IJAAS.

The IJNAS is another beast of a different order. British equipped, Royal Navy indoctrinated and trained, they are a tough bunch of honchos, the cream of the Japanese Navy which already gets Japan’s best, and they know it. Organizationally, outside the carrier air groups, the IJNAS (11th Fleet is the land based headquarters command for non-ship borne INNAS aviation), the IJNAS builds on an airbase ground unit called a squadron (hikotai) composed of four subunits called Shotai (3-4 aircraft section that forms a 12-16 aircraft squadron + 4 reserves for the leadership). These Hokutai might be grouped into 2-4 squadrons together to form a Group (~24-60 aircraft). That is the baseline unit for the 11th Fleet. By 1931 there are five embarked groups on Japan’s carriers (~260 aircraft total, a roughly split in half force of torpedo bombers and scout fighters). The 11th Fleet operates 40 groups of land based aircraft, or roughly 1600 aircraft, of which 200 are seaplanes of all types, about 400 trainers and a mixed force of 1000 aircraft split in half between pure fighters and scout fighter/light bombers. The bombers, are mostly an odd job assortment of the usual twin engine biplanes one sees for the era and one Special Group of heavy bombers which are functionally akin in purpose to the British Vickers Vimy or the American Keystone LB-7 (B-3 and B-6) equipped bombardment groups, used exclusively as pure terror weapons. (The Mitsubishi Ki-20 is based on the German Junkers G-38. It is a deathtrap.) Unfortunately this Special Heavy Bomber Group (特別な衝突のグループ) of 6 planes is based at Atsuga airbase, a fact which Admiral Henry Varnum Butler (TF 10.2 Actual), will discover the hard way as he raids Yokusuka.

WHAT ABOUT THE BLUE TEAM?

The AU USNAS, is an all-Navy show. Even so, though the idea is to obtain unity of purpose as well as unity of command; it is almost as screwed up as the Japanese command setup is. There is Carrier Aviation otherwise known as the United States Navy Air Battle Force (USNABF), Ship-borne Scout Aviation known officially as the United States Navy Forces Afloat Scout Force (USNFASF), Maritime Patrol (USNMP), Homeland/Base Air Defense Aviation (USNBADA), Tactical Aviation (USNTA), Strategic Aviation (USNSA), and the Army Support Service (ASS), the United States Navy Air Transport Service (USNATS), and the Marines off in their corner, running their own United States Marine Corps Aviation (USMCA). Just plowing through the acronyms is acrimonious. Whatever acronym the naval aviator finds himself under, he will be part of a two plane section, that forms a four plane element that forms an eight plane flight that forms a squadron of sixteen planes. Reserves and replacements for squadron operational losses come from central force pools (Group level or higher) Groups on carriers are two to four squadrons+flights (~24-64 aircraft per carrier). Groups ashore are based on plane type (administrative and logistics simplification). Bomber Groups are ~32 aircraft. Fighter groups are ~ 64 aircraft. Seaplanes carried as spotters and recon scouts are administratively carried as assigned to the ship, like another piece of artillery or fire control gear; though a cruiser division that operates together will form an aviation section or flight. Flying boats, shore-based, are treated exactly like bombers organizationally and operationally , even if they are forward deployed and tender supported. This is one thing the USN gets correct. Those Boeing flying boats will come in handy during the Battle of the Volcano Islands.

So what does Congress authorize for the USNAS? The carrier aviation is usually the cream of the crop, both with planes and pilots. Officially the (RTL numbers ~260 aircraft for the actual 5 USN carriers extrapolated to the 9 AU carriers) is supposed to have ~ 360 aircraft on the 6 combat carriers and the 3 training carriers. The numbers fluctuate. The USN has this nasty habit of sending the carriers to sea to support the Marines in the South American banana wars and the seas down there can get rough. Usually about 40 aviators (RTL) a year DIE just in trying to land on the flattops. The aircraft, of course are destroyed too. This is one explanation for the small batch lots that Douglas, Martin, Curtiss, and Boeing manufacture during the 1920s and 1930s and why so many different types proliferate. If one thinks the land-based guys have it any better, then one has not heard of the annihilation of the USN’s lighter than air fleet through operational evolutions in tornadoes and flying weather that should have grounded fixed wing aviation. Speaking of the RTL joys of American land based air? The Keystone LB-7 (B-6) is notorious as a pilot killer during the 1934 RTL Army air mail scandal. There is no truth to the assertion that the pilots who fly it, call it either the “Tombstone” or the “Headstone”.
Anyway… Congress, in its wisdom, authorizes 4 seaplane groups (~ 128 planes), 2 flying boat groups (~32 planes), 10 fighter groups (~480 planes), 3 bomber groups (~ 96 planes), 4 transport groups (~96 planes), 2 Marine Aviation groups (~100 planes) and ~100 scout observation planes to the fleet. There are 6 training groups, for Congress knows that in time of war, the need for pilots will skyrocket. (~192 planes, HAH!), for about 1224 planes ashore, which when added to the carrier aviation, that is about 1,584 aircraft AU (and RTL), authorized. Based on RTL readiness rates and availability, casualties in men and machines and the difference between what Congress will authorize and what it funds, the numbers are a lot closer to 700 aircraft, with the carriers getting the most money, men and machines. This means a front loaded war for Blue against Orange in 1931. It has to be fought that way, If Blue is outnumbered 4-3 in ships, 10-1 in deployable troops and 4-1 in the air. PLAN DOG is a recognition that far from being in a position of inferiority as is supposed; for Orange in 1931, the chances for a Pacific knockout against Blue are the best chances that Orange will ever have. After 1932, the odds climb exponentially. Roosevelt will add 100 ships and triple the air forces by 1938. From 1938-1941 he will double it again.

HOW ABOUT SOME SUBMARINES TO GO WITH THE AIR RAIDS WE FEED YOU?

Congress loves Marines. And Congress loves Sub-marines. It never occurs to the Congress-critters that kilogram for kilogram and man for man, a submarine is twice as expensive as a battleship. But then again, if it is used properly^1, the submarine will kill ten times as many men and twenty times as much shipping as any other class of warship. That includes aircraft carriers… especially aircraft carriers. RTL proof you ask? 12,850,815 gross tons is the accepted losses to U-boats for WW I.

How much tonnage was lost at Jutland? 105,000 tonnes by the British? Maybe 200,000 tonnes in surface actions during the war? We could look at US submarine numbers for WW II and ask the numbers. The Japanese lose 1,178 merchant ships for a total of 5,053,491 tons. The warship losses to US boats are 214 Japanese ships and submarines totaling 577,626 tons. A staggering five million, six hundred thirty one thousand, one hundred seventeen tons, (5,631,117 tons), 1,392 ships total.^2

How does American carrier aviation do? Depends. The numbers seem to skew badly in their favor. The flyboys sink 161 warships (711,265 tons), 359 merchantmen (1,390,241 tons) for a grand total of 520 ships and 2,101,477 tons. Most of those sinkings, however, are in-harbor sitting duck at their moorings ship kills in the final months of the war when the IJN and merchant fleet is forced to homeport for lack of fuel. (courtesy of the US submarine fleet hunting for tankers during the murderous year of 1944.^3)

The thing to which one should pay attention in this AU is that the Americans start out as competent submariners. They do not have the dud captains, dud torpedoes problems of 1941 in 1931. What they have is too few subs. They could use about forty more fleet boats (Type 171s) instead of the thirty or so Type 181s they will get in the 1931 AU emergency program. Using the rule of 1/3 for submarines rotated into combat, leaving combat and in combat, a 67 boat fleet that loses 6 boats in the opening operation of the war will be only able to keep 20 boats on station assigned kill boxes around and near Japan. Operation Kettledrum uses about 12-20 U-boats (Type VII and Type IX) to sink almost 2.5 million tons of shipping off the US east coast in 1942. In 1931, the Japanese have just 3.2 million tons of own flagged merchant shipping. The postulated US Type 171s and the Type 181s use snorts and Type II Sargo batteries^4. The Japanese in 1931 are no better at ASW than they will be in 1944. Dead meat that is.

^1 The Germans kill 14,500,000 tons of allied shipping in WW II. Apparently they use U-boats well in the beginning for a while.
^2 The Americans take 2 years to figure out how. Most of their kills come in 1944. The Americans are slow learners.
^3 Does anyone mourn for the ~40,000 men the Silent Service drowns? One must remember that this kind of war is unspeakably awful.
^4 Friedman, Norman (1995) U.S. Submarines through 1945 Naval Institute Press. ISBN 1-55750-263-3, p. 336. The Italians beat the Dutch to it by ten years ( Capt. Pericle Ferretti 1926 for the Sirena class.). In the AU the USN gets wind of it and adapts the Sirena system to replace their own R-boat snorkels which have not been working.

That's still a battecruiser that has been worked hard without proper maintenance for a few years followed by two years of neglect. And you still have to take her apart down to the waterline in order to perform your modification. And you'll have to do it without such handy things as blueprints and documentation in general.
And there's the not insignificant issue that she's built in metric and the use uses inches and feet. That issue alone has killed many projects.

If your trial carrier must be combat capable you should convert one of your own ships that's under construction or built a dedicated one.

_________________
“Close” only counts with horseshoes, hand grenades, and tactical nuclear weapons.
That which does not kill me has made a grave tactical error

Worklist

Source Materiel is always welcome.

Since, there is the issue of dismounting the heavy guns and re-trunking the funnels and learning how to put a flight deck and hanger over the hull in addition to the problems you mention [see below for reasons to do it], why would one start with the SMS Derfflinger?

• 1. If you plan to convert your own battlecruisers on the stocks to aircraft carriers, you might want to make your mistakes on another ship first. Which should it be? A collier or a purpose built one off expensive useless for combat purposes experiment gone wrong like the Hosho? How about a spare battlecruiser or three that comes in as a prize?

• 2. What fun you will have as you learn about German engineering plants, artillery, ammunition handling, torpedo protection systems (as in none, which is why my drawing has her with a blistered hull to handle both topweight issues and provide a three layer torpedo defense.) and fire control systems. Just how her ventilation system and electric power setup is laid out will advance US knowhow at least a decade. (No South Dakota dead in the water at Guadalcanal because some confused officer manually tripped the wrong cutout. German systems are automatics

• 3. The AU US Navy has been metric ever since 1888 when they adopt Krupp artillery instead of the appallingly awful Whitworth guns the Endicott mission selected. Mister McKinley's navy if you had not noticed, uses German technology right down to the Schwartzkopf torpedoes.

RTL state of know how, USN. About March 1918, the USN has a year of seaplane combat against the German U-boat bases in Belgium under its belt, and a great deal of observation about the Royal Navy Flying Service, who they both admire and sort of disrespect. The USN has about six years of Eugene Ely and Glenn Curtiss experiments under their belts as well. They probably know as much or probably more about what a carrier should look like as the British do. They want to build one to test their own operating theories because it is understood (see above) that one of the reasons the British North Sea blockade has been a shambles, and Jutland as a battle is inconclusive in both the Colbert and Mahanic sense is because the British bungle the reconnaissance. Seaplanes cannot do it. A carrier has to operate with the fleet to bring Zeppelin killing deck launched fighters and some kind of scout plane to sea. That sounds like a large cruiser to the yanks.

They know about the wind over deck problem. An aircraft carrier has to be fast. Curtiss told Moffett when the USN went to Congress*1 in 1918 to expect takeoff runs of at least 200 feet (~60 meters) off a ship that has to run into the wind at least 22 knots or 40 k/h top lift off a Nieuport or one of his Jennies. The USN quickly conclude that they need a 200 meter long ship that can run sustained at 24 knots. Guess what that sounds like? There are the 267 meter long Lexingtons waiting to be reworked, but there are also a boatload of practical unknowns before one orders a halt and redesign and rebuild of partially completed ships on the slips. Why not take an existing battlecruiser apart and put it back together as a carrier first?

The Americans do not want to go through the debacles the British and later the Japanese go through. Aircraft carriers already look to be hideously complex and expensive enterprises. How many time is HMS Furious modified? Three? Four? Akagi goes through two complete and one partial rebuild. The Japanese do not get it right until Soryu. The British are supposed to be world leaders in the art but their carriers compared to the Lexingtons are not as good. That is possibly because the British odd-lotted ships on the slips and did their wartime conversions (Furious) under immense pressure to get something out there, but with Courageous, Victorious, Argus and Hermes, postwar, when the pressure is off, they do not do so well. And this is despite the lessons learned with Furious.

Why not make the mistakes on Derfflinger first? (I drew them into the ships.) Moltke and Lutzow follow and are better each. Those are America's "Courageous class" experiments. The Lexingtons are the real killers.

^1` Norman Friedman remarks in his book about US aircraft carriers that the USN made requests for an aircraft carrier in the annual naval budgets starting in 1918, and that Congress refuses because the American navy could not nail down a final cost for a keel up design that would amount to another battlecruiser in size and expense. Remember, the USN did not even know what kind of planes they would operate yet. The thing is that Friedman gets this wrong. AFAICT the USN cannot come to a consensus on final characteristics, so the collier Jupiter is proposed as a plankover to work the operations problems while C and R tries to come up with a workable keel up design *(Ranger). The Lexingtons are real life WNT accidents that exhibit all the compromises and mistakes one expects from the first purpose designed American carriers.

... What?

http://www.shipscribe.com/styles/S-584/ ... 584-cv.htm

Exactly. The navy could not make up its collective mind from 1918-1922. So what is the point here? That they wanted a keel up design that featured a navigation and deck observation station above the flight deck and to keep exhaust gasses off that flight deck? They already knew this would be a problem. Kings's observations of HMS Argus' operations (1917-18) from tank modelling and the first experiments off USS Birmingham (1910) provide that data. What they do not know, and Friedman glosses over it with a mere mention, is hanger arrangements, tricing, and deck operations. The mistakes they make on the Lexingtons show this.

FLUFF: WHY DO THEY USE BI-PLANES?

Because Bi-planes have good lift characteristics generally, and because with planes taking off from ships, the designers have to be conservative. No forward control canard winged or pusher propeller designs or even monoplanes, unless seriously proven, need apply. Besides, the biplanes have smaller footprints and take up less deck and hanger space. They are easier to trice in a hanger. And they can carry heavier bombloads for the underpowered engines available.

The period is called Mister Hoover's Navy after all. I selected it for very good reasons. The impetus was the original thread elsewhere in this forum of an Anconia type seaplane tender conversion of the Wiesbaden by the Kriegsmarine matched with the 1926 publication of Hector C. Bywater's speculations about a Japanese American war in the Pacific.

The Wiesbaden as an aircraft tender was always going to be nonsense. The Germans know as much about aircraft carriers in 1916 as the fictional man in the moon. If a German battlecruiser is going to become an aircraft carrier, it will have to be the Americans who convert a war prize to do it. The only candidates that fit the bill will be the Derfflinger and the Moiltke. These are the only German ships long enough, wide enough and fast enough to meet the the known wind over deck requirements to get a navalized Nieuport off the deck without a catapult.

Things do not just happen by a snap of the fingers. Thoughts, plans, and experimentation before hull metal is fitted together, must be enjoined. This is especially true for aircraft.

Let us look at the state of the art, ten years after WW I For the USA in its fighter line, that is the F4B (P12). It is a biplane.

Specifications (P-12E) (F4B-1)
Data from Bowers 1989
General characteristics
Crew: one
Length: 20 ft 4 in (6.19 m)
Wingspan: 30 ft (9.14 m)
Height: 9 ft (2.74 m)
Loaded weight: 2,690 lb (1,220 kg)
Powerplant: 1 × Pratt & Whitney R-1340-17 Radial engine, 500 hp (373 kW)
Performance
Maximum speed: 189 mph (304 km/h)
Cruise speed: 160 mph (257 km/h)
Range: 570 miles (917 km)
Service ceiling: 8,020 m (26,300 ft)
Normal ceiling: 3,048 m (10,000 ft)
Armament
Guns: 2 x .30 inch (7.62 mm) Browning machine guns with 600 rounds per gun or 1 x .30 inch (7.62 mm) machine gun with 600 rounds and 1 x .50 inch (12.7 mm) machine gun with 200 rounds
Bombs: 244 lb (111 kg) of bombs carried externally.

The Japanese machines are identical but are only in an evaluation hokutai (squadron) at Sasebo. They are trying (and will succeed in building copies, but at the moment, the Japanese are borrowing British ideas and foreign equipment, so their likely top of the fighter flight line is this:

Specifications (A2N1)
Data from Japanese Aircraft, 1910-1941;[2] The Complete Book of Fighters
General characteristics
Crew: 1
Length: 6.18 m (20 ft 3⅜ in)
Wingspan: 9.37 m (30 ft 9 in)
Height: 3.20 m (9 ft 11 in)
Wing area: 19.74 m² (212.5 ft²)
Empty weight: 1,045 kg (2,304 lb)
Loaded weight: 1,550 kg (3,417 lb)
Powerplant: 1 × Nakajima Kotobuki 2 nine cylinder air-cooled radial engine, 433 kW (580 hp)
Performance
Maximum speed: 293 km/h (158 knots, 182 mph) at 3,000 m (9,845 ft)
Cruise speed: 166 km/h (90 knots, 103.6 mph)
Range: 501 km (270 nmi, 311 mi)
Service ceiling: 9,000 m (29,500 ft)
Normal ceiling: 3,048 m (10,000 ft)
Wing loading: 78.5 kg/m² (16.1 lb/ft²)
Endurance: 3 hours
Climb to 3,000 m (9,845 ft): 5.75 min
Armament
Guns: 2× 7.7 mm (0.303 in) Type 97 machine guns

If that sounds like a Boeing F2B, congratulations. It is.

Just to give you an idea of what the British do; this is the Hawker Hart:

Specifications Hart (Kestrel IB powered day bomber)
Data from The British Bomber since 1914.
General characteristics
Crew: 2
Length: 29 ft 4 in (8.94 m)
Wingspan: 37 ft 3 in (11.36 m)
Height: 10 ft 5 in (3.18 m)
Wing area: 349.5 ft² (32.5 m²)
Airfoil: RAF 28
Empty weight: 2,530 lb (1,150 kg)
Max. takeoff weight: 4,596 lb (2,089 kg)
Powerplant: 1 × Rolls-Royce Kestrel IB water-cooled V12 engine, 510 hp (380 kW)
Performance
Maximum speed: 161 kn (185 mph, 298 km/h) at 13,000 ft
Stall speed: 39 kn (45 mph, 72 km/h) [42]
Range: 374 nmi (430 mi, 692 km)
Service ceiling: 22,800 ft (6,950 m)
Wing loading: 13.2 lb/ft² (64.3 kg/m²)
Power/mass: 0.11 hp/lb (0.182 kW/kg)
Climb to 10,000 ft 8 minutes, 30 seconds
Armament
Guns: 1 × synchronised forward firing .303 in (7.7 mm) Vickers machine gun, 1 × .303 in (7.7 mm) Lewis Gun on Scarff ring in rear cockpit.
Bombs: Up to 500 lb (227 kg) bombs under wings

This thing can dive bomb and hold its own against US and Japanese fighters. Part of the reason for that quality is that British aero engines outperform US and Japanese equivalents by a 8-10 hp per hundredweight ratio and the British until the NACA airfoil survey is completed in 1932 have superior understanding of windflow over wing and better designed propellers. That will change radically by 1935, but we are in `1928-1930 at the moment.

Now why no monoplanes yet? Actually there are a few for the Americans;

Specifications (XP-15. XF5B)
Data from Angelucci 1987, pp. 81–82.[1]
General characteristics
Crew: one
Length: 21 ft 0 in (6.40 m)
Wingspan: 30 ft 6 in (9.29 m)
Height: 9 ft 4.5 in (2.84 m)
Wing area: 157.3 ft2 (14.61 m2)
Empty weight: 2,052 lb (931 kg)
Gross weight: 2,746 lb (1,246 kg)
Powerplant: 1 × Pratt & Whitney SR-1340D, 525 hp (391 kW)
Performance
Maximum speed: 190.2 mph (306 km/h)
Cruise speed: 160 mph (257 km/h)
Range: 420 miles (676 km)
Service ceiling: 27,650 ft (8,428 m)
Rate of climb: 1,800 ft/min (9.15 m/s)
Armament
2 x .30 inch machine guns

The plane is a reject for several reasons; one, it has poor climb; two, its stall characteristics are terrible; three; current fighters can outturn it; four, pilot visibility for landings is poor compared to the referent F4B.

And then there is Lockheed:

Specifications (YP-24. XF1O)
Data from Lockheed Aircraft since 1913
General characteristics
Crew: two
Length: 28 ft 9 in (8.76 m)
Wingspan: 42 ft 9½ in (13.04 m)
Height: 8 ft 6 in (2.59 m)
Wing area: 292 ft² (27.1 m²)
Empty weight: 3,010 lb (1,365 kg)
Loaded weight: 4,360 lb (1,978 kg)
Max. takeoff weight; 5,000lb (2,268 kg)
Powerplant: 1 × Curtiss V-1570-23 "Conqueror" liquid-cooled V12 engine, 600 hp (448 kW)
Propellers: 3-bladed propeller
Performance
Maximum speed: 235 mph (204 knots, 378 km/h)
Cruise speed: 215 mph (187 knots, 346 km/h)
Range: 556 mi (483 nm, 895 km)
Service ceiling: 25,000 ft (7,620 m)
Rate of climb: 1,820 ft/min (9.3 m/s)
Armament
Guns:
1× 0.50 in (12.7 mm) machine gun firing through the propeller
1× 0.30 in (7.62 mm) machine gun firing through the propeller
1× 0.30 in machine gun in rear cockpit

This is my preferred AU aircraft to be modified. The problem is that I have to get rid of the Conqueror engine which is a dog of a maintenance nightmare and handwave a folding wing and the retractable landing gear. This tech is so brand new that the prototype is lost when the pilot makes a forced wheels up landing (He forgets to move the lever to lower the wheels, but with a fire in his lap, can you blame him?), when the engine catches fire in a test flight.

Specifications (V-1570-59)
General characteristics
Type: 12-cylinder liquid-cooled Vee aircraft engine
Bore: 5  1⁄8 in (130.2mm)
Stroke: 6  11⁄32 in (161.1mm)
Displacement: 1,570.4 in³ (25.73 L)
Dry weight: 770 lbs (349 kg)
Components
Cooling system: Liquid-cooled
Performance
Power output: 675 hp (504 kW) at 2,450 rpm
Specific power: 0.43 hp/in³ (19.6 kW/l)

The engine cannot be supercharged without it catching fire or blowing oil everywhere; you know? Your typical piece of Curtiss crap.

So what to do?

Specifications (GR-1820-G2)
Data from Tsygulev[4]
General characteristics
Type: Nine-cylinder single-row supercharged air-cooled radial engine
Bore: 6  1⁄8 in (155.6 mm)
Stroke: 6  7⁄8 in (174.6 mm)
Displacement: 1,823 in³ (29.88 L)
Length: 47.76 in (1,213 mm)
Diameter: 54.25 in (1,378 mm)
Dry weight: 1,184 lb (537 kg)
Components
Valvetrain: Two overhead valves per cylinder with sodium-filled exhaust valve
Supercharger: Single-speed General Electric centrifugal type supercharger, blower ratio 7.134:1
Fuel system: Stromberg PD12K10 downdraft carburetor with automatic mixture control or Hesselmenn ANBAC direct fuel injection.
Fuel type: 87 octane rating gasoline
Oil system: Dry sump with one pressure and one scavenging pump
Cooling system: Air-cooled
Performance
Power output: 700-1,000 hp (520 -746 kW) at 2,200 rpm for takeoff
Specific power: 0,40-0.46 hp/in³ (20.88 kW/L)
Compression ratio: 6.45:1
Specific fuel consumption: 0.6 lb/(hp•h) (362 g/(kW•h))
Oil consumption: 0.35-0.39 oz/(hp•h) (13-15 g/(kW•h))
Power-to-weight ratio: 0.70-0.84 hp/lb (1.10-1.39 kW/kg)

Still leaks oil, is heavier and catches fire, but gives 30% more range and can be supercharged.

Fix the balky landing gear on the Lockheed and voila, strike fighter (1931).