Why the Skua Only Carried a 500lb Bomb

[elbmc1969]

OK, so the point is that the Air Ministry put out a requirement for a monoplane torpedo bomber in January 1938, so a TBD in Great Britain at the time would have little effect.

 

[elbmc1969]

What can the TBD do that the Albacore can't? If the FAA said to Fairey; remove the need for divebombing and a high G high Vne airframe, reduce the fuel capacity, strip out the armour and SS tanks do you think they could deliver a TBD? Probably, but why would the FAA want that?

Not trying to be confrontational, but the Albacore did benefit from a 30% higher empty weight. That gives you a lot more to play with. (And yes, I understand that the combination of the monoplane and a weaker motor meant that the Devastator wasn't going to get off the deck with an empty weight 30% higher.

 

[yulzari]

Looking at the Royal Navy planned progress of carrier aviation the Sea Gladiator/Skua + Swordfish was to be replaced by Fulmar + Albacore and those by the Firefly + Barracuda but progress fell behind but they did recognise and desire better performance. An all Griffon Firefly + Barracuda from 1942 would have been a quite adequate carrier fit to the end of the war had it worked out as planned. In 1939 Skua and Swordfish were a workable, if at the end of their viability.

In the background was the ever changing Firebrand that went from failed Fleet Fighter to the primary naval strike force to cope with the Soviet navy, but we had best not look too closely in the interests of good order and discipline.

A comparison might be to British tank guns. That program was to be the 2 Pounder initially, as the best tank killer in service at the start of the war, thence to the 6 Pounder to replace it in 1940/1 whilst the 17 Pounder was developed for 1943/4. This would have given the Commonwealth first class tank guns throughout the war. However the fall of France delayed the 6 Pounder whilst there was an mis-match between tank and gun design not leaving enough space for the big 17 Pounder except for the Challenger so the 6 Pounder had to soldier on in 75mm form whilst the 17 Pounder was squeezed into the small Sherman turret best operated by midget circus strong men contortionists.

In both cases the overall plan was fine, but execution by industry lagged behind.

 

[RCAFson]

Not trying to be confrontational, but the Albacore did benefit from a 30% higher empty weight. That gives you a lot more to play with. (And yes, I understand that the combination of the monoplane and a weaker motor meant that the Devastator wasn't going to get off the deck with an empty weight 30% higher.

The Albacore (and Swordfish) was stressed for vertical divebombing with a 2000lb bomb load. The requirement for vertical divebombing, large internal fuel capacity, armour and SS fuel tanks mandated a larger and stronger airframe. The STOL requirement, with the available engines, meant that a biplane with a larger wing area was required. However, the Albacore with full internal fuel (no aux tanks) and a torpedo weighed about 10% more than a TBD and with max weapons load and max internal fuel it was about 20% heavier (~12500lb) than the TBD at ~10400lb.

 

[Admiral Beez]

In May of 1940 when the Skuas are performing successful interceptions off the coast of Norway the SBD was not in service.

My bad, I did not intended to suggest a one for one swap, as indeed the Skua and SBD do not overlap, and the non-folding SBD won't fit on Ark Royal (had she survived) nor the Illustrious class. No, my intended point was that if one wanted to use a dive bomber as a stand-in fighter within its service period, the Dauntless does remarkably well considering that unlike the Skua, the SBD was never intended to operate in the fighter role. Online sources report the SBD shot down 138 enemy aircraft, not bad for a divebomber.

 

[RCAFson]

My bad, I did not intended to suggest a one for one swap, as indeed the Skua and SBD do not overlap, and the non-folding SBD won't fit on Ark Royal (had she survived) nor the Illustrious class. No, my intended point was that if one wanted to use a dive bomber as a stand-in fighter within its service period, the Dauntless does remarkably well considering that unlike the Skua, the SBD was never intended to operate in the fighter role. Online sources report the SBD shot down 138 enemy aircraft, not bad for a divebomber.

The SBD of which thousands were built made many kill claims most of which cannot be verified via reference to IJN records. The Skua seems to have shot down more EAs (verified by Axis records) in 1940 than the SBD in 1942...

 

[Shortround6]

The SBD of which thousands were built made many kill claims most of which cannot be verified via reference to IJN records. The Skua seems to have shot down more EAs (verified by Axis records) in 1940 than the SBD in 1942...

One does wonder what an equal number (or greater number, what with folding wings) of Fulmar IIs could have done in the Pacific as CAP instead of Dauntless's in 1942?

At least it solves the Skua vs Dauntless time problem.

 

[SaparotRob]

You giving the Fulmar's back seater any guns? Seeing as how we gave it folding wings.

 

[yulzari]

You giving the Fulmar's back seater any guns? Seeing as how we gave it folding wings.

Fairey found the rear gunner in the Battle had little chance of being effective at battle speeds with the airstream pressures and with the canopy open for the gunner the drag slowed down the Battle and impacted upon the rudder. Hence, with the later light bomber and related Fulmar and then the Firefly, they decided that it would be more effective to fair in the rear cockpit and abandon mounting any gun. It also saved some weight so assisted speed and climb. Albeit a small comparative speed increase. My old RAFVR officer in my ATC squadron was an ex Battle gunner in the Battle of France and said much the same from his experience of wrestling his VGO with a 250 mph slipstream whipping around the raised rear canopy and coming straight into his face.

 

[Reluctant Poster]

My bad, I did not intended to suggest a one for one swap, as indeed the Skua and SBD do not overlap, and the non-folding SBD won't fit on Ark Royal (had she survived) nor the Illustrious class. No, my intended point was that if one wanted to use a dive bomber as a stand-in fighter within its service period, the Dauntless does remarkably well considering that unlike the Skua, the SBD was never intended to operate in the fighter role. Online sources report the SBD shot down 138 enemy aircraft, not bad for a divebomber.

I debunked the SBD claims at Coral Sea previously:

Improved Skua for FAA?

So true!! But let's not forget that even in 1940 the majority of the world's bombers were flying around with defensive positions little more advanced than this... RAFM 158 Despite sweeping technological advances in some areas, other areas suffered lags in development much slower than we often...

ww2aircraft.net

In another post I totaled the actual kills vs claims for the SBD at Eastern Solomons and Santa Cruz based on Lundstroms "The First Team and the Guadalcanal Campaign".

Improved Skua for FAA?

The RN originally intended to have Blackburn build Albacores. But the contract was switched to Swordfish because the jigs were becoming available from Fairey and less need for strategic materials. That enabled the aircraft to be available sooner which in 1939 was what the RN needed. In late 1939...

ww2aircraft.net

At Eastern Solomons the SBDs claimed 6 Vals but actually shot down 0.
At Santa Cruz they claimed 15! Zeros during the strike on the Japanese but actually shot down 0.
At Santa Cruz during the strike on the Americans they claimed
2 Zeros actual 0
9 Vals actual 2
2 Kates actual 0

That's 34 claims vs 2 actual kills
As noted previously, up to and including Coral Sea SDBs claimed 31 EA vs 6 actuals

That gives a grand total of 8 actual kills vs 65 claims

I don't have data for SDB claims at Midway so it is not included

 

[RCAFson]

You giving the Fulmar's back seater any guns? Seeing as how we gave it folding wings.

The Fulmar was designed for and built with folding wings. Some were field modded to accept a Vickers GO MG on a post mount and some observers were given SMGs as a last ditch defense.

 

[SaparotRob]

The Fulmar was designed for and built with folding wings. Some were field modded to accept a Vickers GO MG on a post mount and some observers were given SMGs as a last ditch defense.

Total brain fart about the folding wings on my part.

 

[Beermat]

* The one RAF aircraft that could and did dive-bomb was, of all things, the Westland Whirlwind, which dropped pairs of 250lb in an 80° dive (I think using the trim tabs to recover); why a twin-engined high-altitude interceptor was given this capability I do not know, except that it seems a very Petter thing to do. The problem with overspeeding mentioned in some sources was caused by an unsatisfactory two-pitch prop, which de Havilland solved on a wet wednesday in the Battle of Britain by clocking the blade angle round by about three degrees, but I don't think they ever got a constant-speed unit, which explains why they never met their design performance in the high-altitude interceptor role...

Au contraire - the Whirlwind had a constant speed unit from the outset, controlling a bracket prop. It was actually this that was the problem - the fat blades at altitude experiencing rotational wave drag at transonic speeds causing the mechanism to 'fine' to compensate to the point where no thrust was generated.

It was used for dive-bombing because it was a suitable vehicle for it, really. I don't think Petter had much to do with that decision - some might say that as it was the right one he almost certainly had no connection with it!

 

[tomo pauk]

It was actually this that was the problem - the fat blades at altitude experiencing rotational wave drag at transonic speeds causing the mechanism to 'fine' to compensate to the point where no thrust was generated.

Very interesting. Is there some additional or mandatory reading about this phenomena happening on the Whirly?

It was used for dive-bombing because it was a suitable vehicle for it, really. I don't think Petter had much to do with that decision - some might say that as it was the right one he almost certainly had no connection with it!

LOL

 

[Shortround6]

It was used for dive-bombing because it was a suitable vehicle for it, really. I don't think Petter had much to do with that decision - some might say that as it was the right one he almost certainly had no connection with it!

I will not say they never dive bombed with the Whirlwind but I think it was very, very rare. Of course it may depend on the definition of "dive-bomb" (what angle was used).
I believe they only conducted fighter bomber (not the same thing) trials in Oct 1942 (A&AEE/733A) so it was well after the design/development and it's production life was over.

 

[SaparotRob]

Au contraire - the Whirlwind had a constant speed unit from the outset, controlling a bracket prop. It was actually this that was the problem - the fat blades at altitude experiencing rotational wave drag at transonic speeds causing the mechanism to 'fine' to compensate to the point where no thrust was generated.

It was used for dive-bombing because it was a suitable vehicle for it, really. I don't think Petter had much to do with that decision - some might say that as it was the right one he almost certainly had no connection with it!

While I have little technical understanding of this topic, I do appreciate a good "au contraire".

 

[don4331]

Very interesting. Is there some additional or mandatory reading about this phenomena happening on the Whirly?


LOL

In "The Aviation Historian, Issue 20" staring pg. 39 they go into the issue of thickness/profile/speed and the issues with transonic performance. On pg.44 are the references to original materials.

The DH propellers on the Spitfire were having the same issues - and the article proposes that the same solution would have greatly improved the Whirly's altitude performance.

 

[tomo pauk]

In "The Aviation Historian, Issue 20" staring pg. 39 they go into the issue of thickness/profile/speed and the issues with transonic performance. On pg.44 are the references to original materials.

The DH propellers on the Spitfire were having the same issues - and the article proposes that the same solution would have greatly improved the Whirly's altitude performance.

I've take a look at the article. It is certainly very informative.

What is puzzling to me is the usage of words like "it appears", "possibly", "in this possible condition", "whether or not", "there is little doubt", all in less than two pages - why use that kind of wording in the 1st place?

 

[don4331]

I've take a look at the article. It is certainly very informative.

What is puzzling to me is the usage of words like "it appears", "possibly", "in this possible condition", "whether or not", "there is little doubt", all in less than two pages - why use that kind of wording in the 1st place?

I understand - bottom line, Whirly was never tested with thin propellers, so it is a bit of a what-if. But why the author is starting from a possibility, he doesn't need to keep using "weasel words." My wind tunnel work has been at hi-way speeds, so I'm not an expert on whether a difference between 9 and 9.6% thickness would make that much difference. It seems to have for the Spitfire

All the work that NACA put into the airfoil design of propellers goes largely uncredited, but it made enormous difference in the capabilities of the USAAF and USN fighters.

 

[tomo pauk]

I understand - bottom line, Whirly was never tested with thin propellers, so it is a bit of a what-if. But why the author is starting from a possibility, he doesn't need to keep using "weasel words." My wind tunnel work has been at hi-way speeds, so I'm not an expert on whether a difference between 9 and 9.6% thickness would make that much difference. It seems to have for the Spitfire

Thank you for understanding where I'm coming from.

All the work that NACA put into the airfoil design of propellers goes largely uncredited, but it made enormous difference in the capabilities of the USAAF and USN fighters.

Probably not as 'sexy' as other fields of aero-nautical business.