Was the Sea Fury Britain's first carrier aircraft with power folding wings?

[Admiral Beez]

The FAA's Hellcats and Tarpons (Avengers) had power folding wings, but I don't believe any of the British-build carrier aircraft of WW2 had power folding? Is the postwar Sea Fury the first?



Why did it take so long? This postwar Seafire has them, why not the earlier models?

 

[EwenS]

Grumman developed its STO-Wing folding system in 1940/41. It was designed around a hydraulic system. But wing folding added weight to the F4F Wildcat so sapping performance. So to minimise the performance loss the folding wing F4F Wildcats were fitted with a manual system instead.

When the folding wing Seafire III was developed in 1942/43 power folding was seen as most desirable due to man power issues amongst carrier deck crews. BUT the weight increase to provide it (especially with the double fold) was unacceptable due to the effect it would have on performance on what was basically a modified, and already heavier, Spitfire V. Then the Seafire XV/XVII used the same wing and folding mechanism, but was only seen as an interim aircraft pending development of the Spitfire XXI based Seafire 47 with the single wing fold. Powered folding on Seafire 47 was fitted from the 5th production aircraft which first flew in Feb 1947.

Most of the main British naval aircraft types of WW2 began development before mid-1940. Many suffered substantial weight growth. Powered folding on the likes of Barracuda and Firefly would simply have exacerbated the performance problems they had.

By the end of the war more powerful engines were available and new types entering service then got power folding. But the post war slowdown meant it was 1946-48 before Seafire 47, Sea Fury F.10 and Sea Hornet F.20 and later Firefly versions began to reach front line units.

The nature and tempo of carrier operating cycles changed significantly between 1940 and 1942 highlighting the need for power folding.

 

[pbehn]

Did the sea Mosquito get them? I cant find any info.

 

[EwenS]

Did the sea Mosquito get them? I cant find any info.

Sea Mosquito TR.33 had manually folded wings after the first 13 aircraft had been built. It was only ever envisaged as a low production variant and power folding would have meant complete redesign of the hydraulic system with the added weight that that brought.

Admiralty plans in 1944 envisaged a total of 72 being acquired for 2 squadrons (24 aircraft each) as alternative air groups for HMS Implacable & Indefatigable plus a photo squadron (12 aircraft) plus another 12 for trials and training. The purpose was to provide a long range strike / PR capability for the Far East, something that the Director of Plans felt was beyond the capability of the USN at the time.

With the end of the WW2 the production order was cut back from 100 to 50 with another 6 built as TR.37 with a different radar in the nose. The only front line FAA squadron with Mosquitos was 811 squadron, which had reformed on Mosquito VI on 15 Sept 1945 to work up on the type. These were gradually replaced with 12 TR.33 between April and August 1946. It operated these until it disbanded on 1 July 1947.

A whole range of second line FAA squadrons operated various versions of the Mosquito during the latter part of the war and then into the postwar years.

 

[MikeMeech]

The FAA's Hellcats and Tarpons (Avengers) had power folding wings, but I don't believe any of the British-build carrier aircraft of WW2 had power folding? Is the postwar Sea Fury the first?



Why did it take so long? This postwar Seafire has them, why not the earlier models?

Hi

While the Avenger/Tarpon had power folding, as far as I can find the Hellcat had manual folding like the Wildcat/Martlet. Indeed the Grumman 'sto-wing' system is very similar to the earlier (1937) Blackburn Skua folding system:

The Supermarine system for folding wings proposed in 1939 for the 'Sea Spitfire' (from 'Spitfire, The History' by Morgan & Shacklady) also appears to be similar to the later Grumman system:

Or the system of the two-seat N 8/39 proposal (from same source):

These were also manual (as they had been on bi-planes from 1912 onwards). As has been mentioned power folding did increase the weight of the system and it became more viable and necessary as aircraft got heavier and had more engine power.

Mike

 

[GregP]

Here's the F4F Wildcat "Power" wing fold system.

 

[Thumpalumpacus]

Here's the F4F Wildcat "Power" wing fold system.

Like I used to joke about my old 73 Toyota -- "it's got Armstrong power-steering."

 

[BiffF15]

Here's the F4F Wildcat "Power" wing fold system.

"Man" power.

 

[Admiral Beez]

A lot easier than the Seafire.

 

[EwenS]

Hi

While the Avenger/Tarpon had power folding, as far as I can find the Hellcat had manual folding like the Wildcat/Martlet. Indeed the Grumman 'sto-wing' system is very similar to the earlier (1937) Blackburn Skua folding system:
View attachment 660209
The Supermarine system for folding wings proposed in 1939 for the 'Sea Spitfire' (from 'Spitfire, The History' by Morgan & Shacklady) also appears to be similar to the later Grumman system:
View attachment 660210
View attachment 660211
Or the system of the two-seat N 8/39 proposal (from same source):
View attachment 660216

These were also manual (as they had been on bi-planes from 1912 onwards). As has been mentioned power folding did increase the weight of the system and it became more viable and necessary as aircraft got heavier and had more engine power.

Mike

I'm confused about the Hellcat. This training film states that hydraulic power was at least required to lock the wings in place (see from 1.20 onwards) once they were unfolded. But it shows one / two men only on each wing as they were unfolded.


Doesn't seem very much manpower when compared to this training film on carrier flight deck operations with the Wildcat (see around 4.30 onwards)


Even the video above has 3 involved plus one overseer (elf and safety no doubt!)

I can't find anything at the moment actually showing a Hellcat's wings being either folded or unfolded. They always seem to on deck with wings spread. Sods law when you are looking for something.

 

[Admiral Beez]

Hmm…. I assumed the F6F Hellcat had power folding since both the Corsair and Avenger did.

 

[GreenKnight121]

The Hellcat is listed as having optional power-folding. All Hellcats had the power-fold system installed, but it could be easily disabled for manual folding if so desired... and many squadrons on USN carriers did that to reduce wear on the aircraft systems.

 

[Admiral Beez]

Here's the Avenger (edit) fold. I thought the engine had to be running to generate the hydraulic power?

 

[BiffF15]

Here's the Hellcat fold. I thought the engine had to be running to generate the hydraulic power?

AB,

Avenger fold vice the Hellcat (typo). My assumption is it's an electric hydraulic pump as that's what it sounds like. The OV-10 had one (made by the lowest bidder) that worked the gear and flaps, as well as the 767, A319 and A320 (assume the rest of the "320" types have them as well).

Cheers,
Biff

 

[DarrenW]

as far as I can find the Hellcat had manual folding like the Wildcat/Martlet.

All Hellcats had the power-fold system installed, but it could be easily disabled for manual folding if so desired...

I think there's a bit of confusion on how the F6F's wing folding system worked. The pilot's manual specifically states that the wings are spread and folded manually from the ground, with the only hydraulic portion or "power" control available was related to the wing hinge locking pins. There was never a system installed which gave full hydraulic control of the wing folding procedure.

There was a two position control lever on the right hand cockpit shelf which operated the locking pins, and a "T" handle control on the lower center control panel to control the safety locking pins. These safety locking pins prevented the main locking pins from disengaging, regardless of hydraulic pressure.

So it would be incorrect to say that the F6F had power folding wings in the sense we understand that to mean (like we find in aircraft such as the Corsair). But there was a hydraulic element to accomplishing the wing folding procedure if we include the wing hinge locking pins. This can understandably be confusing to some.