Grumman Martlet Mk II questions

[MDriskill]

The Martlet II appears to have been built in two sub-variants. Some early aircraft with "A.M." serials (yes, note periods after the letters!) had British-spec catapult spools, and an extended fairing between the landing gear, as seen in the shot below.

 

Later aircraft with "AJ" serials seem to have dispensed with both features.

 

What was the cut-off point? Did all the "A.M." machines have the early features?

 

Another noticeable difference was the tall over-wing pitot on the early aircraft, vs. the small under-wing one on later machines. I suspect this change was not connected to the spools though.

 

 

Edited January 7, 2022 by MDriskill

[ClaudioN]

3 hours ago, MDriskill said:

What was the cut-off point? Did all the "A.M." machines have the early features?

I made a few notes over the years, sources by now forgotten. One that may be relevant is:

"a picture of A.M.997, taken in late November 1942, shows this to have neither British-standard catapult spools, nor the lengthened fairing between the landing gear struts"

 

3 hours ago, MDriskill said:

Another noticeable difference was the tall over-wing pitot on the early aircraft, vs. the small under-wing one on later machines. I suspect this change was not connected to the spools though.

This was Grumman's first attempt to provide a pitot for the folding wing aircraft. Another note I have says:

"this form of pitot tube was used only on the early examples; A.M.974 appears to be already fitted with the smaller, L-shaped underwing pitot – see IWM A 11637, Admiralty Official Collection".

Curiously, another photo shows that the first Martlet II (A.M.964) initially had BOTH the overwing pitot and the F4F-3 style straight pitot tube on the wing leading edge.

[MDriskill]

Thank you! That's great information.

[Geoffrey Sinclair]

I cannot help with the catapult and fairing details, the production details might provide some clues, given the gaps.

 

According to Air Arsenal North America AM954 to 999 were built first, then AJ100 to 153.

 

Martlet II acceptances, 10 in March 1941, 1 in June, then 49 from August to December 1941, then 1 in February, 22 in March and 6 in April 1942.  F4F-3 production ended in September 1941 (then revived January to May 1943) , F4F-4 production began in November 1941.  The F4F-4B order had 1 accepted in March 1942, then production from June to December 1942.

 

Does anyone have a figure on how many Martlet II had folding wings?  The XF4F-4 first flight 14 April 1941, officially accepted in May.

[Grey Beema]

This may not be a lot of help and you have probably seen it before but I have referred to it quite often.

 

http://www.clubhyper.com/reference/wildcatfaaba_1.htm

[EwenS]

I looked into the Martlet II deliveries a few years back combining information from the article @Grey Beema linked, Sturtivant’s FAA aircraft and a few other sources. In summary:-

 

Britain ordered 100 Martlets as Mk.II in 1940.

 

The first 10 were delivered in March 1941 with fixed wings - serials AM954-963. These later get relabelled Mk.III

 

Britain learns of Grumman’s folding wing and obtained agreement to defer the rest of the batch until it is productionised. It flies about June 1941 and production aircraft start flowing in Oct 1941.

 

The first folding wing aircraft are delivered between 4/10/41 and 12/12/41. 36 in total serials AM964-999. These are put aboard HMS Illustrious in time for her to sail from the USA to Britain on 16 Dec. Most of these aircraft were then issued to 888 squadron on Formidable and 881 & 882 on Illustrious when they sail for the Indian Ocean in Feb/March 1942.

 

Deliveries continued with 54 aircraft AJ100-153. 13 in Dec 1941 (AJ100-112) and the remaining 41 (AJ113-153) in March/April 1942. These aircraft were crated up and shipped direct to the Far East as attrition replacements (destination Bombay and Ceylon) beginning 15/3/42 with the last arriving 25/4/42. Four were lost en route. This was the period of greatest crisis in that theatre and modern single seat fighters were desperately needed to counter the Japanese Zero.

 

Now for the catapult spools. I don’t think that there was any difference between the AM and AJ serialled Martlet II. The spools were designed to support the aircraft on the catapult trolley used with the British BH.III accelerator (catapult). But they were removable. Loading an aircraft onto the trolley was a bit of a faff and the RN preferred free take offs, especially with lightweight fighters. So most of the time aircraft didn’t have them fitted. They added to aircraft weight and drag and the Martlet needed neither hindrance. Looking at other aircraft types, they rarely appear unless the aircraft is actually being loaded onto the catapult trolley.

 

There is another potential, but less likely, reason given the aircraft markings. With the arrival of US types the RN began to look at tail down launching. Martlet II AM991 was being used for such trials in April-July 1942 on a US built escort carrier (either Avenger or Biter) following their arrival in Britain. At some point after that the BH.III accelerator on the Illustrious class was modified to allow tail down launches of US aircraft types. The BH.III fitted to Implacable, Indefatigable and the Colossus class from late 1943 were so configured from the outset. Unfortunately I have not so far managed to identify when this would have happened or how complicated a job it was (dockyard or ships’ engineers).

 

The RN was still using the trolley to catapult launch British types through to the end of the war (Fireflies on Implacable in June 1945 for example). The first British type designed for tail down launching was the Seafire XV produced from late 1944.

 

So returning to the initial query, my bet is that the first aircraft has the spools fitted but not the second.

 

And now you have aroused my curiosity, does anyone know if the Lend Lease Martlet IV / F4F-4B (delivered 1 on 27/2/42 and the remaining 219 between June & Nov 1942) and the later Mk.V / FM-1 and Mk.VI / FM-2 were fitted with British catapult spools. My gut feeling is that they probably didn’t.

 

 

[ClaudioN]

10 hours ago, EwenS said:

Now for the catapult spools. I don’t think that there was any difference between the AM and AJ serialled Martlet II. The spools were designed to support the aircraft on the catapult trolley used with the British BH.III accelerator (catapult). But they were removable.

My understanding was that catapult spools were fitted by Blackburns after delivery by Grumman. Spools required some local strengthening to the airframe and I do not think that Grumman, already under pressure to expedite deliveries to both the USN and the FAA, would be prepared to put in the extra work for this mod.

I believe eventually a Blackburn-run modification centre was set up to carry out modifications according to FAA requirements for any Grumman aircraft (for instance, the observer position on the Tarpon/Avenger). I have been unable to find out whether the centre was located in the US or in Britain, I believe Martlet mods were carried out at Abbotsinch, UK.

 

As to deliveries, the situation is a bit more complex. In Sturtivant's book only 24 aircraft (A.M.964-A.M.987) are listed as being ferried aboard Illustrious. Nine more (A.M.988-A.M.996) are reported as being at Lee-on-Solent around the end of 1941/beginning of 1942, so they might have been ferried by carrier, too, making a total of 33. Two of the Martlets flown off Illustrious were lost on arrival to the UK, two more were lost during training in early 1942. An Admiralty document gives 29 available for Formidable and Illustrious (though A.M.991 was retained in Britain), suggesting that numbers seemingly match.

A further 12 aircraft were delivered to Illustrious along the way to the Indian Ocean, HMS Archer ferrying them directly from the USA to Freetown. These are expressly mentioned in a report by Illustrious CO (ADM199/937) as Martlet IIs (unmodified). I assume these aircraft are among those reported by Sturtivant as being shipped to... (some Indian Ocean destination).

 

I would think highly unlikely that any of the Martlets delivered straight to the Eastern Fleet received the catapult spool mod. Just a feeling, but photos seem to confirm those minor differences were there.

 

14 hours ago, Geoffrey Sinclair said:

Does anyone have a figure on how many Martlet II had folding wings?  The XF4F-4 first flight 14 April 1941, officially accepted in May.

 

AFAIK, all 90 Martlet IIs had folding wings. The first ten of the 100-aircraft order (A.M.954-A.M.963) had fixed wings and were re-designated Martlet IIIs, as already said by @EwenS.

 

Plus, one of the Martlet Is retained aboard Illustrious for 'Ironclad' was fitted with folding wings while aboard the carrier.

This is explicitly stated in the report referred to above, I know nothing more about it. Any additional information would be extremely welcome!

Edited January 6, 2022 by ClaudioN

[MDriskill]

You gents never cease to amaze me! Again, many, many thanks for all the excellent info - as usual, you've gone entirely above and beyond my request.

 

For what little it's worth, I personally have never seen a photo of any Martlet with FAA catapult spools, other than some "A.M." Mk II's. I didn't know the spools were removable, most interesting.

 

What was the function of the extended fairing between the landing gear? Was that part of Blackburn's spool installation? This image is from a video clip on the "Armoured Aircraft Carriers" site, poor quality, but shows the shape rather well (and, it appears not to have any spools?):

 

 

 

Edited January 8, 2022 by MDriskill

[Geoffrey Sinclair]

Thanks for the mark II non folding wing information.

 

The British import report has no Martlet III.  The Martlet II and IV imports, month, number, mark, destination

May-41, 9 Martlet II UK

Jan-42, 32 Martlet II UK

May-42, 1 Martlet II UK

May-42, 12 Martlet II Mombasa

Jun-42, 7 Martlet II Mombasa

Jul-42, 1 Martlet II UK

Aug-42, 10 Martlet IV UK

Aug-42, 13 Martlet II Mombasa

Sep-42, 40 Martlet IV UK

Oct-42, 60 Martlet IV UK

Oct-42, 3 Martlet II Mombasa

Nov-42, 14 Martlet IV UK

Nov-42, 30 Martlet IV Mombasa

Dec-42, 3 Martlet IV UK

Feb-43, 7 Martlet IV UK

 

Totals 35 II and 30 IV for Mombassa, 43 II and 134 IV for UK, so 78 II and 164 IV.  Versus 100 II and 220 IV accepted for the RN, with 4 mark II lost at sea en route.  Things like the 12 mark II delivered to Illustrious at Freetown in March/April 1941 probably did not make the imports figures, that still leaves 6 unaccounted for.  The import reports ignore aircraft that were a part of unit movements, and the RN formed a number of units in North America.

 

For completeness,  The 30 Wildcat originally meant for Greece arrived in the Middle east, 27 in July and 3 in October 1941.  Total mark V imports 268 (versus 312 accepted) and 338 mark VI (versus 340 accepted, the last in April 1945)

[ClaudioN]

6 hours ago, Geoffrey Sinclair said:

May-41, 9 Martlet II UK

According to Sturtivant A.M.954, the first G-36B, was retained by Grumman in the US for trials, which explains why only nine arrived in May 1941. Wheteher and when it reached Britain is not reported.

[MDriskill]

A few Martlet IV's (aka "F4F-4B" to the US Navy) were retained in the US as trainers, retaining full FAA regalia. Charger operated on Chesapeake Bay. Identifying these must have been interesting for local residents!

 

Per notes I made MANY years ago (source long forgotten 😬), 320 Mk IV's serials were assigned, FN100 - FN319; unlike other Lend-Lease Wildcats, apparently there were no parallel USN Bu Aer serials. This image is from Dana Bell's excellent book:

 

Edited January 8, 2022 by MDriskill

[ClaudioN]

4 hours ago, MDriskill said:

Thank you very much for the image.

I had some fun cross checking with "Fleet Air Arm Aircraft 1939-1945", "The Squadrons and Units of the Fleet Air Arm" and the Navy List for February 1943, and the result is rather interesting to me.

Side number 8x indicates that FN256 is an aircraft of No.896 Sqn., shore based based at NAS Quonset Point (HMS Asbury), right before embarcation in HMS Victorious for her deployment to the Pacific.

Pilot: Sub-Lt. R. C. Wilkinson, RNVR

A particularly interesting photo as Victorious Martlets in 1943 are so elusive.

[Seahawk]

Several interesting features in that very useful image: NB the prop blade markings and the upper/lower camouflage demarcation line, which seems to follow a panel line most of the time - and is much less easily seen when the aircraft is the right way up!

[MDriskill]

23 hours ago, ClaudioN said:

Side number 8x indicates that FN256 is an aircraft of No.896 Sqn., shore based based at NAS Quonset Point (HMS Asbury), right before embarcation in HMS Victorious for her deployment to the Pacific.

 

That makes entirely too much sense! Why would a US trainer have FAA squadron markings...?

Edited January 9, 2022 by MDriskill

[Geoffrey Sinclair]

According to Air Arsenal North America, just like the B added to make them F4F-4B, so a set of Bureau Numbers ending in B were created for the RN Martlet II order, 0031B to 0250B, for the 220 aircraft involved but the B serials were in some cases duplicated and caused confusion, so the system was abandoned.  One of the few USN orders the USAAF WS-378 report for 1940/42 covers is the Grumman G-36B order BR-A-1548 for Britain, all 100 exported, monthly export figures being

 

9 in Apr-41
5 in Jan-42
6 in Feb-42
11 in Mar-42
24 in Apr-42
45 in Jun-42

Which do not fit the early 1942 British import figures at least.

 

Amazingly the RAF has contract cards for the Martlet I, II and most of the IV order, given it is an aircraft built in the US for the RN.  About 30 cards of information.

 

Mark I.  Data includes arrival and departure dates at Scottish Aviation for AX824 to 9 and BJ507 to 512.  The mark I order is put at 95 thanks to some serials from the Greek order aircraft listed as mark I.

 

Mark II deliveries are put as 8 in June and 1 in July 1941, 27 in January, 5 in February, 8 in March, 24 in April, 6 in May, 20 in June and 1 in July 1942, total 100.  Nice except AM954 is listed as lost at sea USA/UK 23 February 1942.  AM956 to 963 delivered in June, AM955 in July 1941, AM960 to 963 marked "fixed wings". AM964 to AM996 delivered January and February 1942 (except AM967 to UK on SS Brimanger? delivered July 1942), it might be possible to work out which arrived on Illustrious.

 

AM997 to 999 shipped direct to Bombay, delivered March 1942.  All of AJ100 to 153 are listed as shipped direct to Bombay or China Bay, if I have deciphered the hand writing correctly, except for AJ150 to UK, with AJ107, 109 to 111 listed as lost at sea.  I suspect delivery month is when the aircraft left the US.

 

Martlet IV order deliveries, 10 in August, 49 in September, 122 in October and 14 in November 1942, total 195 on the summary card but FN100 to 308 have contract card entries (so 209 entries, 10 of which say December delivery), (Serials for the order of 220 went to FN319) most are marked USA to UK, but others have units as the allocation, 590?, 890, 894 (in USA) squadron, others list Mombassa, while FN205 to 7, 240 lost at sea, FN295, 296, 299, 300 blank entries.

 

There is also a summary of some early RN aircraft orders from Grumman, requisition and contract numbers. 

[tempestfan]

20 hours ago, Seahawk said:

Several interesting features in that very useful image: NB the prop blade markings and the upper/lower camouflage demarcation line, which seems to follow a panel line most of the time - and is much less easily seen when the aircraft is the right way up!

And a rather clear view of my particular little obsession, the small blister in front of the outboard case chute, which according to Richard Dann is not shown on Grumman drawings (I had a short conversation with him on HS in the Stone Age about it), and hence not represented on any drawings apart from those by Jumpei Temma.

[MDriskill]

Again, thanks for the info! I was not familiar with Air Arsenal North America, but now have a copy on the way.

 

Here is some truly trivial trivia for the Martlet II modeller. My guess is that these are early examples with "A.M." serials:

 

1) Yellow arrows: on most Wildcats, the small rectangular door that accesses the crank for the wing fold lock pin is hinged on its inboard side. On these machines - the very first folding F4F's - it is hinged at the rear. I would think the later version is less susceptible to handling damage.

 

2) Blue arrows: Some of these machines have the small teardrop bulge in front of the wheel (required to clear an intercooler joint flange on two-stage supercharged aircraft), while others do not. Superfluous for the single-stage Mk II, possibly Grumman decided it was more expedient to have only one version of this panel.

 

 

Last but not least, this site has a great selection of very clear Martlet photos, many of them new to me:

 

http://www.axis-and-allies-paintworks.com/e107_plugins/forum/forum_viewtopic.php?14422

 

Edited January 12, 2022 by MDriskill

[Steve in Ottawa]

On 1/9/2022 at 2:47 PM, MDriskill said:

Last but not least, this site has a great selection of very clear Martlet photos, many of them new to me:

 

http://www.axis-and-allies-paintworks.com/e107_plugins/forum/forum_viewtopic.php?14422

 

Sady, it looks like all the photo links are dead. ☹️

[ClaudioN]

15 minutes ago, Steve in Ottawa said:

Sady, it looks like all the photo links are dead.

They come from the archives of San Diego Air and Space Museum, you should be able to find them here:

https://www.flickr.com/photos/sdasmarchives/albums

[dogsbody]

2 hours ago, Steve in Ottawa said:

Sady, it looks like all the photo links are dead. ☹️

 

Works for me, up here, on The Backside Of Beyond.

 

 

Chris

[janneman36]

And me so all fine and thank you for sharing😁👌