ORIGINAL: Xargun
I've been watching my engine production lately and its going the wrong way - stockpiles are draining so I'm been going over my aircraft / engine plans in more detail to correct the issue before its too late. Cannot accurately plan engines until I have my aircraft plans locked down so here is my aircraft plans (including numbers where applicable):
CV Aircraft
A6M2 Zero (x120) until A6M5c Zero (x120) until A7M2 Sam (x100)
D3A1 Val (x40) until D4Y3 Judy (x60) until D4Y4 Judy (x60) [May not build D4Y3 depending on need when available]
B5N2 Kate (x50) until B6N2a Jill (60)
Land-base Fighters
A6M2 Zero (above) until J2M3 Jack (x100) until N1K2-J George (x100)
N1K5-J George (x60)
J7W1 Shinden (x100)
Ki-43-Ic Oscar (x120) until ki-44-44-IIc Tojo (x120) until Ki-100-I Tony (x120)
Ki-84a Frank (x??) until Ki-84r Frank (x??) [May wait until Ki-84r completely - depending on need]
Ki-63 (x??)
Night Fighters
J1N1-S Irving (x60) until P1Y2-s Frances (x60)
Ki-45 KAId Nick (x??) until Ki-102c Randy (x??)
Level Bombers
G3M2 Nell (x60) until G3M3 Nell (x60)
G4M1 Betty (x30) until end of war [Long range night bomber]
P1Y1 Frances (x60) until P1Y2 Frances (x60)
Ki-21-IIa Sally (x60) until Ki-49-IIa Helen (x60) until Ki-49-IIb Helen (x90)
Ki-67-Ia (T) Peggy (x??)
Recon
C5M2 Babs (x30) until C6N1 Myrt (x30) until C6N2 Myrt (x30)
Ki-46-II Dinah (x30) until Ki-46-III Dinah (x30)
Patrol
H6K4 Mavis (x30) until K8K2 Emily (x30)
Transport
L3Y2 Tina (x30) until L2D2 Tabby (x30)
H6K4-L Mavic (x30) or H8K2-L Emily (x30) [Should I build one or the other or both ??]
MC-21 Sally (x30) until Ki-49-II KAI Helen (x30)
Float
E13A1 Jake (x30) until E13A1b Jake (x30)
Please comment on my plans above - especially numbers. As I have said I have had little to no experience with late game (44+) and only a little experience with late 43 so my numbers may be way off.
I would try to hold A6M2 production to 90. It is ok to set it to 120, but try to stop expansion at 90 if you are able to sufficiently maintain your squadrons with only 90 (it is hard to do, especially against your oppnent). The A6M2 factories never upgrade for free and it hurts when you shut most of them down only 10 months after expanding them. Oscar at 120 is ok. The Oscar factories will upgrade for free throughout the war, and Oscar has its purposes, especially as a fighter-bomber. So you will shut down and restart these factories from time to time as the war progresses. Val at 40 is ok. You will be short Vals to fill out your squadrons until mid February no matter what you do. You probably will not need 50 Kates. 30 should be enough.
I would focus on eather George or Jack and put only 30 in the other. I prefer George. I doubt you will ever field the Shinden. Better to focus exclusively on A7M2 Sam. You will not need 30 Mavis. 10 or 15 is enough. They are engine hogs. Try to use more Jakes- 1 engine versus 4 is a huge HI advantage. Ditto for C5M2s. 30 Dinahs seems high as well. 20 should suffice. The H6K4 Mavis transport is useless in PDU:ON, since your normal Mavis can function as a transport.
You will probably not need so many Frances. Though they later model is an excellent night bomber. If you want to pursue a late war night bombing strategy (which is what I recommend for PDU:on), then research into Frances is Ok to get the night bomber (it is the radar-equipped model). 60 Sallies and 90 Lillies is also high. Far too many engines. 30 of each should be enough.
For army transports just use the original Topsy until the obsolete engines run out, then switch to something else: either the new Topsy (to save political points) or the Thalia. The 2nd generation Topsy uses an important engine, (I forget which one), so it may be a no go. The MC-21 Sally has less range than the Topsy and Thalia. The Tina is your best transport, but alas it is navy. You only have 1 navy squadron of transports and only get 1 more, so 5 Tinas is enough for a month.
As I mentioned, your best 1943 fighter is the Ki-63 Tony. It is fast, with a high ceiling, uses 1 engine, and has 2 accurate cannons. It is the Japanese P-38. I would advise building some of these to bridge between Tojo and Frank. Because of its high ceiling, it also works well as the high fighter in layered cap with Tojo, Frank, and Oscar. Focus on only 2 end-war army fighters at the most. Frank is obvious. Everyone has their own opinion on the other. Lowpe and Pax would have a better idea than me which performs best.