Why was the Barracuda so much slower than the Avenger?

[RCAFson]

I wonder what Fairey (or any of the British firms) would have come up with before the war for a fleet fighter if specified as follows:

1) Single seat
2) Single engine
3) Monoplane
4) Retractable undercarriage
5) Fitted with 8 mg with possible upgrade to four 20mm or combo
6) 330 mph or faster with competitive rate of climb
7) 900 mile combat endurance
8) Foldable to less than 20ft wide and 12ft high
9) Wide robust undercarriage with good forward view
10) Good low speed handling

This of course assumes that the priorities of war, the need to get the Spitfire, Hurricane, etc. into immediate service can be addressed.

That's a big ask in 1936-38. Even in Sept 1939 no SE fighter existed anywhere that could meet those requirements.

 

[Admiral Beez]

That's a big ask in 1936-38. Even in Sept 1939 no SE fighter existed anywhere that could meet those requirements.

My thinking is that it would be a pre-war Specification, but would not enter service until 1940 or early 1941.

 

[RCAFson]

My thinking is that it would be a pre-war Specification, but would not enter service until 1940 or early 1941.

The AM/FAA issued specification N.8/39 in 1939:

Specification N.8/39 and N.9/39
Blackburn Firebrand
and Fairey Firefly
In 1938 work began on two new specifica-
tions for the FAA, N.5/38 for a two-seat fighter
and N.6/38 for a turret fighter. These were
quickly updated to N.8/39 and N.9/39, both
dated 21st June 1939. N.8/39 called for a top
speed at 15,000ft (4,572m) of at least 275
knots (317mph/5l0km/h) and an inter-
changeable armament of eight forward-firing
0.303in (7.7mm) Browning machine guns or
four 20mm cannon; N.9/39's requirements
were identical apart from four Brownings in a
turret. On 10th August the two documents
were issued to tender to seven companies
and five had replied by 19th September...
...On 23rd December [1939] the Admiralty reported
that the N.8/39 tenders were unsatisfactory
and revealed fresh requirements for single-
and two-seat fighters; the turret fighter was
now abandoned. The specifications were
modified under a document called NAD.925/39
and proposals for alternative single- and two-
seat types were requested. The former
required a maximum speed of 330 knots
(380mph/611km/h) at 15,000ft (4,572m), the
two-seat 300 knots (345mph/556km/h). The
designs produced to this unofficial document
were relatively quick investigations with fold-
ing wings and other naval fittings.

(Buttler, British Secret Projects...)

 

[Thumpalumpacus]

The AM/FAA issued specification N.8/39 in 1939:

Beezy's first stipulation was "Single seat".

 

[RCAFson]

Beezy's first stipulation was "Single seat".

Read the bottom half of the quote.

 

[Thumpalumpacus]

Read the bottom half of the quote.

And which domestic single-seat proposal was taken in hand? I'm struggling to think of any single-seat FAA fighter that wasn't a converted RAF fighter or purchased from America. His hypothetical service date of "1940-41" narrows the window a lot. What project do you sacrifice in order to get this hot-shot operational in the FAA by 40-41?

 

[RCAFson]

And which domestic single-seat proposal was taken in hand? I'm struggling to think of any single-seat FAA fighter that wasn't a converted RAF fighter or purchased from America. His hypothetical service date of "1940-41" narrows the window a lot. What project do you sacrifice in order to get this hot-shot operational in the FAA by 40-41?

There was no way to get such an aircraft into series production in less than two years.

Fairey proposed a single seat fighter and the Blackburn Firebrand was accepted and built to that spec. The Hawker Sea Fury originated from that proposal as well.

 

[Thumpalumpacus]

There was no way to get such an aircraft into series production in less than two years.

Agreed, which is why I think mentioning that spec isn't really apt. Beezy's kinda asking for the Moon in that time-frame, I think. Took us Americans near the end of 41 to get the Wildcat operational, and the Japanese around the middle of that year(?) to get the Zero operational, and neither of those meet all his specs.

 

[EwenS]

Agreed, which is why I think mentioning that spec isn't really apt. Beezy's kinda asking for the Moon in that time-frame, I think. Took us Americans near the end of 41 to get the Wildcat operational, and the Japanese around the middle of that year(?) to get the Zero operational, and neither of those meet all his specs.

The Zero reached the front line from July 1940 initially with a trials unit. By Sept they had two units flying them in China alongside the A5M.

The carrier capable A6M2 Model 21 version went into production in Nov 1940 and began to reach the carrier squadrons from early 1941. Over 350 were in service by PH.

The Martlet I entered front line service in Oct 1940 and the first squadron went aboard the escort carrier Audacity to work up in July 1941.

 

[Jabberwocky]

I wonder what Fairey (or any of the British firms) would have come up with before the war for a fleet fighter if specified as follows:

1) Single seat
2) Single engine
3) Monoplane
4) Retractable undercarriage
5) Fitted with 8 mg with possible upgrade to four 20mm or combo
6) 330 mph or faster with competitive rate of climb
7) 900 mile combat endurance
8) Foldable to less than 20ft wide and 12ft high
9) Wide robust undercarriage with good forward view
10) Good low speed handling

This of course assumes that the priorities of war, the need to get the Spitfire, Hurricane, etc. into immediate service can be addressed.

An even more disappointing Blackburn Firebrand?

Check out the responses to Specification N.8/37, which called for development of a carrier-based single-seat fighter for the Fleet Air Arm, capable of at least 380mph at 15,000ft and armed with 8 Mags.

EDIT: d'oh, beaten to the punch.

 

[Thumpalumpacus]

The Zero reached the front line from July 1940 initially with a trials unit. By Sept they had two units flying them in China alongside the A5M.

The carrier capable A6M2 Model 21 version went into production in Nov 1940 and began to reach the carrier squadrons from early 1941. Over 350 were in service by PH.

The Martlet I entered front line service in Oct 1940 and the first squadron went aboard the escort carrier Audacity to work up in July 1941.

So they're on the early side of his timeline (40-41) but still don't fulfill his stipulations ... which was my point.

 

[Shortround6]

So lets see how the 2-3 contenders do, P for Pass and F for fail.

Requirement....................................................................................................Martlet I.........................F4F-3......................................A6M2

1) Single seat.........................................................................................................P.....................................P................................................P
2) Single engine....................................................................................................P.....................................P...............................................P
3) Monoplane.......................................................................................................P......................................P...............................................P
4) Retractable undercarriage..........................................................................P......................................P...............................................P
5) Fitted with 8 mg.............................................................................................P......................................P...............................................P
6)with possible upgrade to four 20mm or combo................................F.......................................F...............................................F
7) 330 mph or faster..........................................................................................F.......................................P..............................................P
8) with competitive rate of climb.................................................................F.......................................F...............................................P
9) 900 mile combat endurance.....................................................................F.......................................F...............................................P
10) Foldable to less than 20ft wide and 12ft high................................F........................................P..............................................F
11) Wide robust undercarriage with good forward view...................F.......................................F...............................................P
12) Good low speed handling.......................................................................P......................................P...............................................P

I gave everybody a pass on the eight .303 requirement. I am not going to argue about four .50s vs eight .303s or two 20mm vs six .303s
The upgrade to four 20mm is fail, I am assuming since this was a British spec (hypothetically) that the 20mm intended was the Hispano gun.
Martlet I fails the speed requirement.
The Martlet and F4F-3 fail the range/endurance requirement. it says combat, not ferry.
Martlet and F4F-3 both fail the WIDE undercarriage requirement, it may have been sturdy (?) but it was narrow and tippy.

The Zero has the best record after the first 4 requirements (which could have been passed by anything designed after 1938)
however the A6M2 had a few problems in late 1940 and early 1941.
1 was the no folding wing to start, Folding was introduced in production with the 67th airframe.
2 there was a back and forth with fitting a tab on the Aileron for better roll response.
3 there was an early crash with one of the A6M1 prototypes that lead to a number or restrictions on the first 50 aircraft built and modifications to later ones.
4 a second crash in April 1941 was traced to wing failure due to overstraining the wing by lowering speed at which the wing began to flutter due to the aileron balance tab which had not been part of the original design.
Solutions used on all Zeros built after May of 1941 include.
1. Increase thickness of outer wing skin
2, Install longitudinal stringers to increase torsional strength
3, add external balance weights to ailerons pending redesign of ailerons to use internal weight/s.
4 Pilot confidence in the balance tab system was ruined and the tab system was removed until early 1943.

edit> this decreased the roll response of the early Zero's. <edit

The Zero was used in China in 1940 but it was not quite the Zero of late 1941. ALL Zeros used at Pearl Harbor had been built between May and Nov of 1941.

BTW the list does not include either armor or fuel tank protection. None of the candidates had it.

 

[SaparotRob]

I'm a fan of the A6M but does that wing tip fold look a bit ridiculous lame unimpressive to anyone else?

 

[Shortround6]

I'm a fan of the A6M but does that wing tip fold look a bit ridiculous lame unimpressive to anyone else?

It did what was required.
Made it easier to get the planes on and off the lift/elevator with the least amount of weight gain possible.

Be careful what you ask for. The designers just may give it to you.......................and nothing more.

 

[Admiral Beez]

I'm a fan of the A6M but does that wing tip fold look a bit ridiculous lame unimpressive to anyone else?

The Japanese ditched it on later variants. The tip fold didn't do much to help with stowage.

 

[warbird51]

Possibly obvious, but I find it puzzling that according to Wiki the Barracuda's maximum speed was 38mph slower than the Avenger's despite:

• only 60hp less
• inline vs radial engine
• smaller wings
• lighter

The Avenger can carry a torpedo internally, but I'm assuming max speed is without torpedo? I'm not an aerodynamicist but just eyeballing pictures I don't see any screaming red flags like fixed landing gear (which anyway might not hurt too much at those speeds) or the Skua's vertical windscreen. Would the struts on the tail make that much difference?

Other guesses:

1. Wiki is just wrong? (Neither plane makes wwiiaircraftperformance.org, if anything the other numbers out there are even worse for the Barracuda, not so much for the Avenger.)
2. The Fairey-Youngman flaps add drag out of proportion to the extra wing area (I assume they are counted as part of the wing area)?
3. Thicker wings (relative to chord/absolutely)? The Avenger was NACA 23015 which is 15% thickness at the root (which seems surprisingly thin?). I can't find the Barracuda's airfoil, eyeballing it may be a bit thicker?
4. Aerodynamics is just weird and it doesn't need to be anything big/obvious?

(I'm thinking of the immediate aerodynamic reasons, not any underlying doctrinal reasons e.g. the Barracuda's dive bomber requirement.)

Edit: I guess another possibility is if the Merlin had worse altitude performance than the R-2600? The Wiki speeds don't come with altitudes but 16k vs 22k service ceiling does seem significant...

Edit 2: Other numbers are all over the place but don't indicate it's just an altitude thing e.g. Barracuda Max speed: 228mph at 1,750ft or 210mph at 2,000ft
Avenger Maximum speed 271 mph (436 km/h) at 11,200 feet (3400 meters) 251 mph (404 km/h) at sea level

Because it was British????

Ducking now!!

 

[Shortround6]

The Japanese ditched it on later variants. The tip fold didn't do much to help with stowage.

It wasn't intended to help stowage.
It was intended to reduce the chances of wing tip damage when transporting the aircraft on the carrier lifts/elevators.
The Early Zeros had wing spans nearly identical to the width of the elevator shafts on certain carriers.
Later Zeros had the wing tip shortened (A6M3) and left square or shortened and rounded (A6M5).
Neither did anything for stowage but made handling aboard carriers easier.

 

[Admiral Beez]

It wasn't intended to help stowage.
It was intended to reduce the chances of wing tip damage when transporting the aircraft on the carrier lifts/elevators.

Well, in the act of stowage then.

 

[Shortround6]

Shokaku
The forward elevator was larger than the others to allow aircraft that had just landed to be moved below without folding their wings and measured 13 by 16 meters (42 ft 8 in × 52 ft 6 in). The other elevators were narrower, 13 by 12 meters (42 ft 8 in × 39 ft 4 in)
A6M2 wing span 39ft 4 1/2in.
D3A Val

Pretty much the same deal. Enough fold to get up and down the elevators.

 

[EwenS]

Similar reasoning to the T shaped lifts on early British carriers. In an era without barriers or deck parks forward for aircraft just landed. Roll them forward onto the lift, strike them down into the hangar, and fold the wings as the aircraft is pushed off the lift into the hangar itself. Helps speed up the landing cycle.