Could you have designed a better Warbird?

[Clay_Allison]

Then use R4M rockets with HEAT warheads. No critical resources are required. Even a Me-109G6 can kill tanks (and heavy bombers too!) using this weapons system.

You have to have a real pair of balls to hold your fire down to breath-smelling range, which is what you'd have to do to hit with bloody unguided rockets.

 

[davebender]

R4M rocket - Wikipedia, the free encyclopedia
The R4M was the world's first effective folding fin rocket. It's not like the previous clunkers used by Britain, Germany and the USA.

R4Ms were usually fired in four salvos of six missiles at intervals of 0.07 seconds from a range of 600 m. Two warheads were available for the R4M, the common PB-3 with a 0.4 kg charge for anti-aircraft use and the larger shaped charge, similar in construction to the Panzerschreck, the Panzerblitz II (PB-2), for anti-tank use

So....
You approach the target and fire all 24 rockets in less then 5 seconds from a range of 600 meters. The law of averages suggest you are going to hit something.

A crazy man like Bronc will then charge in to finish the job with cannon fire. As for me, I firewall the throttle and head back to the airfield for another load of rockets. 8)

 

[Vraciu]

Hi guys,
an idea came to me today to make a fighter for the Japanese which would combine best abilities of such aircraft like Ki-61/Ki-100, Ki-84, J2M and N1K2-J. Main fuselage of three sections like Ki-84 in order to simplify production process. I want to adopt engine cowling from Raiden for Homare engine (it would lead to make some changes in NK9A, but I think that it's worth it - aerodynamics). Then, center section from Shiden-kai, canopy from Hayate. Third section of fuselage: combined Ki-84 and Ki-61 (just bottom from the latter). Wings from Shiden-kai, maybe a bit longer. Armament of 4x20 mm Ho-5 cannons (2 per each wing) or 2x20 mm Ho-5 and 2x30 mm Ho-155 cannons. Engine, as said before - NK9 Homare, maybe version for J2M's cowling would be called Model 32. I hope, if engineers would do their job properly, it will produce 2,200-2,300 hp. It would be good to equip it with supercharger but to be honest I don't know if there was such possibility for Homare or even for any engine in Japan AD 1944/45. Propeller with design from Raiden but adjusted for Homare performance. Cockpit with center from N1K2-J and sides from Hien (design of course, controls adjusted for other kind of aircraft and other kind of engine), seat from Hien. Radio equipment - Type 4 Hi Model 3, as I know it's the best Japanese aircraft radio of WW2. Type 4 gunsight (God, I would like to have an AceMaker Japanese equivalent, but...). Undercarriage from Ki-61/Ki-100 (u/c of remaining trio caused problems for non-experienced pilots). Ability to get one droppable fuel tank under fuselage (for 300 l of fuel) and two under wings (one per wing, 200 l each). With three additional tanks and, I hope, ca. 700 l in internal tanks, the maximum range would be even about 3,000 km. Instead of fuel tanks ability to get some bombs, of course (2x250 or 3x100 I think). So, and that's it. Any ideas to improve the project? I will start making some drawing soon.

Regards from Poland,
Chris

 

[Vraciu]

Well, I'm thinking now about changing the engine to NK11 or MK10 (about 2,500 hp each one). And about A7M3-J.

Regards

 

[Vraciu]

Here it is, some changes made:
powerplant is MK9D, undercarriage is from A7M3-J, tailwheel from Ki-84, behind tailwheel is tailhook for carrier landings, wings are combined N1K2-J's and Ki-100's and folded like F6F's ones (Japanese had one F6F so they could copy it).

Length is 11,78 m,
Wingspan - 15,12 m.

Regards from Poland,
Chris

 

[davebender]

Japan, Germany and Italy all made great fighter airframes. Give them adequate quantities of good aircraft engines (plus fuel!) and they have everything necessary for a superior aircraft.

In the case of Japan they need a reliable copy of the 1,350hp DB601E V12 in mass production NLT January 1942 to power the Ki-61 IJA fighter. That would give 1942 Japan the best fighter aircraft in the Pacific and one of the finest in the world.

 

[Vraciu]

Yes, but servicing liquid-cooled engines in jungle was a serious problem for Japanese. Allied mechanics were accustomed for them and Japanese were not. That's why Japanese preferred radial, air-cooled engines.

 

[davebender]

servicing liquid-cooled engines in jungle was a serious problem for Japanese.

If Japan produces enough DB601 aircraft engines then it's not an issue. Worn out engines get replaced and shipped back to the factory for rebuild rather then trying to overhaul engines at front line airfields. That's what the WWII era Luftwaffe did and I think most air forces operate that way in the modern world.

 

[Shortround6]

If Japan produces enough DB601 aircraft engines then it's not an issue. Worn out engines get replaced and shipped back to the factory for rebuild rather then trying to overhaul engines at front line airfields. That's what the WWII era Luftwaffe did and I think most air forces operate that way in the modern world.

It is one thing in the modern world and another thing in WW II.
While the engines may not have been overhauled at front line fields the allies certainly used regional depots to over haul engines. Engine repair shops in Cairo overhauled engines for the Mediterranean theater. I am sure that the 8th and 9th Air forces over hauled engines in England rather than ship them back and forth to the US. Pacific theater probably also had overhaul facilities.
The Japanese may have established regional depots/shops also. It is not like they can drive the engines in a truck to a local rail line and get get them to the factory in a couple of days and get replacement engines the same way like a Continental power could. It is either fly the engines 1,2, or 3 at time using scarce transport aircraft or use ships taking weeks to get back and forth. while there are replacement engines available engines sitting in freighter holds don't do anybody any good.
Shipping bearing, ring and gasket sets is a whole lot easier than shipping complete engines. Throw in a few connecting rod/piston sets, some valves and valve springs and few other parts and you can cover a fair amount of over haul needs.
The British gave the US 600 Merlins as both complete engines and for breaking down for parts for engine replacement-parts for repair and overhaul for Merlin powered P-40s in North Africa. I doubt that they sent the 600 engines to the United States to be Broken down.
Even in the 1950-60s the US and Nato were working to to overhaul engines in Europe. German and Italian companies were contracted to repair/overhaul jet engines rather than ship them back to the US for overhaul. I believe at least one Japanese company got similar contracts. In some cases this repair/overhaul work lead to licence manufacture of parts if not complete engines.

Sometimes licence manufacture is not all that easy. A country has to have all the parts suppliers in line and up to spec for it to work. Some engine companies did not make their own bearings but bought them from specialty companies (Allison's profitable part of the business during the 1930s).
Bristol was actually dependent on Swedish roller bearings for the Hercules engine for much of WW II.

 

[renrich]

Here is a simple and easily done way to come up with a great fighter design for WW2. You take what is arguably the best all around fighter of the war anyway, the F4U. You redesign the structure so that the wing and fuselage section does not have to carry the loads of a carrier landing. Likewise the landing gear. The aft fuselage is lightened because it does not have the carry through of the shock of the tail hook catching the wire. All of this saves weight. You delete the anti corrosion treatments necessary for duty at sea. You leave in the two internal wing tanks which gives you an internal fuel capacity of 361 gallons. You delete the right wing leading edge spoiler that evens the stall characteristics and the plane can turn tighter. That spoiler is not needed for land based duty. You use automatic blower controls instead of manual to lighten the pilot load. If you want more armament you go with the two 20mms and four 50 cals like some of the Hellcats had.

You wind up with a long range, even better maneuvering, heavily armed, fast and fast climbing, rugged fighter that can do almost any job.

 

[johnbr]

What the Ki 61 need was 605 with a two stage supercharger.

 

[cocky pilot]

I dont know the technical details yet but I have an anglo american design team called the hindsight committe working on it and we have already come up with the names.

Production would be carried out by Supermarine Westland and Vickers in UK and Curtiss Douglas and Northrop in the US

Naming is as follows for all planes

Supermarine shudabin
Westland wudabin
Vickers Virtually
Curtiss Couldabin
Mitchell Mightabin
Northrop Neighon


Fighters will have the suffix Unbeatable and Bombers suffixed Unstoppable

At present my favourites are the Supermarine Shudabin Unbeatable Mk 4 (jet powered to mach .9 with six cannon)and the Northrop Neighon Unstoppable Mk2 cruising at 60,000ft with 10 ton bomb load.

 

[koivis]

It would be good to equip it with supercharger but to be honest I don't know if there was such possibility for Homare or even for any engine in Japan AD 1944/45.

Every single aircraft engine producing over 1000 hp had a supercharger in WW2. Every one of them. What you are probably meaning is a turbosupercharger.

What the Ki 61 need was 605 with a two stage supercharger.

What the DB 605 did not need was a two stage supercharger. It already had a variable-speed supercharger, driven through a barometrically controlled clutch.

 

[Vraciu]

What you are probably meaning is a turbosupercharger.

You're probably right. Sorry for my English. In Polish turbosupercharger is in fact "turbosprezarka" but I thought that "sprezarka" is simply charger.

BTW I have another idea of never-were aircraft - medium bomber for RAF, a slightly bigger Canberra with 2 Centauruses.

Regards

 

[cocky pilot]

You're probably right. Sorry for my English. In Polish turbosupercharger is in fact "turbosprezarka" but I thought that "sprezarka" is simply charger.
BTW I have another idea of never-were aircraft - medium bomber for RAF, a slightly bigger Canberra with 2 Centauruses.
Regards

In the UK a supercharger is driven from the engine and a Turbocharger driven from the exhaust. As with all things it is easy to say and not so easy to do.

There is a difference between two stage and two speed, heres some wiki info on the merlin.
__________________________________________________________________________________________________________________________
Central to the success of the Merlin was the supercharger. A.C. Lovesey, an engineer who was a key figure in the design of the Merlin, delivered a lecture on the development of the Merlin in 1946; in this extract he explained the importance of the supercharger:

"Coming now to specific development items we can ... divide them into three general classes:

Improvement of the supercharger.
Improved fuels.
Development of mechanical features to take care of the improvements afforded by (1) and (2).
Dealing with (1) it can be said that the supercharger determines the capacity, or ... the output, of the engine. The impression still prevails that the static capacity known as the swept volume is the basis of comparison of the possible power output for different types of engine, but this is not the case because the output of the engine depends solely on the mass of air it can be made to consume efficiently, and in this respect the supercharger plays the most important role ... the engine has to be capable of dealing with the greater mass flows with respect to cooling, freedom from detonation and capable of withstanding high gas and inertia loads ... During the course of research and development on superchargers it became apparent to us that any further increase in the altitude performance of the Merlin engine necessitated the employment of a two-stage supercharger."[26]
As the Merlin evolved so too did the supercharger; the latter fitting into three broad categories:[27]

Single-stage, single-speed gearbox: Merlin I to III, XII, 30, 40, and 50 series (1937–1942).[nb 3]
Single-stage, two-speed gearbox: experimental Merlin X (1938), production Merlin XX (1940–1945).
Two-stage, two-speed gearbox with intercooler: mainly Merlin 60, 70, and 80 series (1942–1946).
The Merlin supercharger was originally designed to allow the engine to generate maximum power at an altitude of about 16,000 feet (5,000 m). In 1938 Stanley Hooker, an Oxford graduate in applied mathematics, explained "... I soon became very familiar with the construction of the Merlin supercharger and carburettor ... Since the supercharger was at the rear of the engine it had come in for pretty severe design treatment, and the air intake duct to the impeller looked very squashed ..." Tests conducted by Hooker showed the original intake design was inefficient, limiting the performance of the supercharger.[28][nb 4] Hooker subsequently designed a new air intake duct with improved flow characteristics which increased maximum power at a higher altitude of over 19,000 feet (5,800 m); and also improved the design of both the impeller, and the diffuser which controlled the airflow to it. These modifications led to the development of the single-stage Merlin XX and 45 series.[29]

A significant advance in supercharger design was the incorporation in 1938 of a two-speed drive (designed by the French company Farman) to the impeller of the Merlin X.[30][nb 5] The later Merlin XX incorporated the two-speed drive as well as several improvements that enabled the production rate of Merlins to be increased.[32] The low-ratio gear, which operated from take-off to an altitude of 10,000 feet (3,050 m), drove the impeller at 21,597 rpm and developed 1,240 horsepower (925 kW) at that height; while the high gear's (25,148 rpm) power rating was 1,175 horsepower (876 kW) at 18,000 feet (5,490 m). These figures were achieved at 2,850 rpm engine speed using +9 pounds per square inch (1.66 atm) boost.[33]

In 1940 Rolls-Royce considered adapting the Merlin to use an exhaust-driven turbocharger to increase the power of the Merlin. Although a lower fuel consumption was an advantage, the turbocharger was rejected in favour of a two-stage supercharger.[34] The basic design, first tested in September 1941, used a modified Vulture supercharger for the first stage while a Merlin 46 supercharger was used for the second.[35] A liquid-cooled intercooler on top of the supercharger casing was used to prevent the compressed air/fuel mixture from becoming too hot.[nb 6] Fitted with the two-stage two-speed supercharger, the Merlin 60 series gained 300 horsepower (224 kW) at 30,000 feet (9,144 m) over the Merlin 45 series,[35] at which altitude a Spitfire IX was nearly 70 miles per hour (113 km/h) faster than a Spitfire V.[36]

 

[Shortround6]

What the DB 605 did not need was a two stage supercharger. It already had a variable-speed supercharger, driven through a barometrically controlled clutch.

This seems to be one of the more common/persistent myths.

The variable-speed supercharger drive replaced the 2 speed drive used on a number of other engines but the variable-speed supercharger drive could do nothing to improve/change the actual pressure ratio of the supercharger itself.

DB 605's used a higher compression ratio than allied engines and so could not use as much boost as allied engines without detonation. DB 605's, with their larger displacement didn't need as much boost to make their rated power.

The DB 605A was compressing the surrounding air just under 3 times at 5700meters for it's 1.42 ata rating. Power fell off above this height.

The Merlin 61 at 23,500ft was compressing the surrounding air just over 5 times to make its rated power at 15lbs of boost which is close enough to 2.0 ata to make no real difference to this discussion. At the time no single stage compressor could get anywere near a 5:1 pressure ratio no matter how it was driven.

 

[davebender]

I agree.

If Japan wants the Ki-61 program to be successful they must sink some serious money into facilities for manufacture of the DB601 engine and it's sub-components. Otherwise they are wasting their time. The same goes for Italy if they want the DB601 / DB605 engine for their Macchi C.202 fighter aircraft.

 

[billswagger]

I'm not sure how outrageous this concept would be, but how about a variable gear ratio for the reduction gearing.
Perhaps something that works like an actual transmission?
I'm not sure of the benefits of such a concept anyhow.

Other than that, i would expand on a more stream line 109, removing the wing radiators and developing a rear section similar to the mustang's.

 

[tomo pauk]

Bf-109G-2 "a better warbird":
Bf-109F-4 hull, MGs deleted, plugs between wings and hull containing cannons (added benefit would've been better undercarriage layout), wings without rounded wingtips so span would almost the same, but the wing area slightly increased, new fuel tank instead of hull MGs and their ammo.

 

[Vraciu]

I made somewhat similar project about two years ago, but I have taken Bf 109G-14 as basic structure. Here you go:

Powered by DB 605ASM, armed with 1 MK108 and two or four MG151/20s, it has normal undercarriage (assembled inwards like Fw 190's, unlike Spitfire's or original 109's) and canopy which provides better visibility (it comes from Fw 190). Lenght is 9,55 m.

And here is our "Ultimate Axis Fighter" which I made today.

Powered by DB603, armed with 5 MG151/20s, fuselage is combined Bf 109G-14/G.55/Ki-61/Ki-84/my A8K/N1K2-J, wings are my original project (they have combat flaps), undercarriage comes from G.55, canopy from Ki-84, as cockpit is, but I equipped it with Kommandogerat. German radio equipment and gunsight.
Lenght is 10,22 m.

And here are plans I reffered to during work:
Ki-61

G.55

N1K2-J (from Z.J. Krala book "Kampanie powietrzne II wojny światowej. Daleki Wschód cz. VIII")

Bf 109G-14 (from K. Janowicz book "Bf 109G/K vol. II")

Ki-84 (from K. Zalewski book "Samolot myśliwski Nakajima Ki-84 Hayate Frank")

Regards