Was a British Nakajima B5N possible?

[Admiral Beez]

In January 1937 the Nakajima B5N1 Kate first flew, entering IJN service in late 1937 or early 1938. The Kate was a retractable undercarriage, all-metal, monoplane, folding wing torpedo bomber with max speed of 229 mph, ceiling of >24,000 feet with a range of 669 miles, powered by the 770 hp Nakajima Hikari 3 Nakajima B5N (Kate)

This was a significant increase in overall performance over the USN's Devastator and RN's Swordfish. In B5N2 form with the 1,000 hp Sakai engine, entering service in 1939 max speed increased to 235 mph, ceiling to >27,000 feet, with a cruise speed of 160 mph, but with reduced range of 608 miles.

Was a British equivalent of the B5N1, with these above specs possible to enter service by spring 1938? To me, the biggest barrier is the engine. The all-metal, retractable undercarriage, folding wing monoplane Blackburn Skua first flew in February 1937, a month after the Nakajima B5N1, so we know the FAA and AM knew how to work in this spec.

 

[Shortround6]

In January 1937 the Nakajima B5N Kate first flew, entering IJN service in late 1937 or early 1938. The Kate was a retractable undercarriage, all-metal, monoplane, folding wing torpedo bomber with a max speed of 235 mph, a cruise speed of 160 mph and a range of 608 miles. This was a significant increase in overall performance over the USN's Devastator and RN's Swordfish.

Yes and no. The B5N1 Kate first flew in Jan 1937 However.....

The later prototypes and first several years of production aircraft differed considerably from the first prototype. They got a more powerful 9 cylinder radial and the Fowler flaps and powered wing folding were changed to simpler flaps and manual folding wings for easier maintenance.
The B5N2 with the 14 cylinder Sakae engine (same as used by the early Zero) didn't fly until Dec 1939.
This is the version that was used in the early Pacific fighting. The earlier version seeing a fair amount of use in China in 1938-39.

Earlier version was only a small amount off in performance. In 1939 the Japanese issued the specification that lead to the B6N and the US issued the specification that lead to the TBF.

The British had an engine comparable to the 9 cylinder engine used in the B5N1. Fit the Pegasus and the British would actually have a better engine. But by 1939-40 both the Japanese and the British would need something better.

 

[fastmongrel]

A British version is going to be heavier with less fuel. Probably need a bit more power which leads to more weight.

 

[tomo pauk]

Almost there: Fairey Battle with 9 cylinder radial engine (Cyclone in this particular aircraft).

 

[Admiral Beez]

Yes and no. The B5N1 Kate first flew in Jan 1937 However.....The B5N2 with the 14 cylinder Sakae engine (same as used by the early Zero) didn't fly until Dec 1939.

This same chronology could work for the Brits. FAA monoplane, all-metal, retractable undercarriage torpedo bomber first flies in 1937, but like the B5N1 it is underpowered. The British introduce a few of these into service, but continue to rely on the Fairey Swordfish whilst engine development continues. Dec. 1939 the first higher powered FAA aircraft flies, same as the B5N2. By 1941 the FAA's replacement, akin to the B6N flies. So, we're essentially looking to replace the Albacore with a British all metal monoplane. We're still challenged by what engine to use.

 

[Admiral Beez]

A British version is going to be heavier with less fuel. Probably need a bit more power which leads to more weight.

Problems to be overcome for certain. We definitely do not want a British equivalent to the slow, plodding Devastator.

Dauntless? Yes please! But the Brits are better off making their own all-metal, monoplane TSR.

 

[fastmongrel]

Can the Fulmar be the basis of a Torpedo bomber. The undercarriage might need moving outward to provide space for a fish.

 

[Admiral Beez]

Can the Fulmar be the basis of a Torpedo bomber. The undercarriage might need moving outward to provide space for a fish.

The Fulmar is a little late, not flying until 1940. We're looking for a monoplane, all-metal TSR to first fly in 1937, same year as the B5N1 and Skua. The Hawker Henley also first flies in 1937, but the RR Merlin may be underpowered in its early days.

Maybe start with the Skua? Wider wingspan, improve streamlining (including that near-vertical windscreen), more powerful engine (when available), reduce weight through omission of dive bomber and fighter equipment, including removing dive brakes, reduce forward armament and incorporation less armour (the Swordfish and Albacore had essentially no armour for the aircrew).

Someone made a good attempt here Blackburn Skua Mk III

 

[fastmongrel]

The Fulmar is a little late, not flying until 1940. We're looking for a monoplane, all-metal TSR to first fly in 1937, same year as the B5N1 and Skua. The RR Merlin may be underpowered or not available in its early days.

Maybe start with the Skua? Wider wingspan, improve streamlining (including that near-vertical windscreen), more powerful engine (when available), reduce weight through omission of dive bomber and fighter equipment, including removing dive brakes, reduce forward armament and incorporation less armour (the Swordfish and Albacore had essentially no armour for the aircrew).

Blackburn Skua Mk III

The Fairey P4/34 which became the Fulmar flew 13 Jan 1937
Fairey P.4/34 - Wikipedia

 

[fastmongrel]

I think the radiator needs moving. Maybe a chin radiator but that's pig ugly so prefer wing root.

 

[Admiral Beez]

I think the radiator needs moving. Maybe a chin radiator but that's pig ugly so prefer wing root.

Definitely doable. I never liked the Fulmar or early Fireflies chin rad. I'd avoid the wing root rads as well, as that takes up internal fuel space. Instead put the rads under the wings like on the Spitfire. Keep a clean belly for the torpedo.

Thoughts on a recess to keep the torpedo tight against the lower fuselage? Like how the Skua has a recess for its bomb.

 

[SaparotRob]

The Fulmar is a little late, not flying until 1940. We're looking for a monoplane, all-metal TSR to first fly in 1937, same year as the B5N1 and Skua. The Hawker Henley also first flies in 1937, but the RR Merlin may be underpowered in its early days.

Maybe start with the Skua? Wider wingspan, improve streamlining (including that near-vertical windscreen), more powerful engine (when available), reduce weight through omission of dive bomber and fighter equipment, including removing dive brakes, reduce forward armament and incorporation less armour (the Swordfish and Albacore had essentially no armour for the aircrew).

Someone made a good attempt here Blackburn Skua Mk III

I tried that link and it seems I'm permanently banned from that site. Which is rather insulting since I've never been there.

 

[Admiral Beez]

I tried that link and it seems I'm permanently banned from that site. Which is rather insulting since I've never been there.

Cheeky sods, lol. Here's a PDF printout.

 

[Jay Flynn]

Fairey did offer a monoplane TSR version during the development of the Swordfish. Not quite as advanced as the B5N,,,but in 1937ish.....

 

[fastmongrel]

Major problems for all designs is horse power. I reckon 12 or 1300 horsepower is the minimum requirement. Can we get Rolls Royce to update the Buzzard or Bristol to build a 14 cylinder Pegasus.

 

[fastmongrel]

Fairey did offer a monoplane TSR version during the development of the Swordfish. Not quite as advanced as the B5N,,,but in 1937ish.....

Fit folding gear and a good engine and you have a decent 1937 bomber. Still be as slow as cold custard though.

 

[fastmongrel]

A horrid mash up of the Fairey Mono and a Firefly nose. My paint skills are very nearly zero

 

[Admiral Beez]

Fairey did offer a monoplane TSR version during the development of the Swordfish. Not quite as advanced as the B5N,,,but in 1937ish.....

IK, but I'm looking for all-metal, retractable undercarriage. fastmongrel forget about those canvas wrapped slowpokes. Let's push the British designers to bring their best. I bet Petter from Westland could have made a winner.

 

[Jay Flynn]

View attachment 612119

Fit folding gear and a good engine and you have a decent 1937 bomber. Still be as slow as cold custard though.

Taurus? Maybe 200-10mph?

 

[Jay Flynn]

Taurus? Maybe 200-10mph?

The Albacore got 170mph with it. Maybe even 220-230mph with retracting u/c