An Allison V-1710 with a two-speed supercharger in 1942

[andy1967]

Hi
No. 515 Sqn. and the Defiant is mentioned in 'The Aircraft of 100 Group' by Martin Streetly:
View attachment 875380
View attachment 875381
The same author's book 'Confound and Destroy' has some data on the type:
View attachment 875382
Mike

Thanks Mike.

 

[andy1967]

Hi
Note the start date is July 1943. If we look at the ORBATs included in the volume, first the 1 July 1943:
View attachment 875373
View attachment 875374
You will note that No.263 Sqn. still has Whirlwinds and that No.515 Sqn. still has some Defiant IIs alongside Beaufighter IIs. Then the ORBAT for 1 January 1944 shows they are gone:

View attachment 875375
View attachment 875376
Mike

Interesting to learn that Spitfire Va and Hurricane IV including in the Order of Battle.

 

[Geoffrey Sinclair]

Some repetition with other messages from a long interruption while writing this one. Eastern India Monsoon, mid May to October which tended to decrease air operations. Remember the effects on air supply/transport requirements from the Chindit operations in the first half of 1944 and the Japanese attack on Imphal in March.

SEAAC had
31 December 1943, 1,393 Hurricane, 136 Spitfire, 184 Beaufighter, 110 Dakota
30 June 1944, 2,760 Hurricane, 469 Spitfire, 319 Beaufighter, 205 Dakota

Comparison of USAAF India figured with the USAAF Statistical Digest is not possible as the digest table includes China. CBI Losses January to October 1944 were 423 (152 to enemy aircraft, 94 to AA, 177 other causes), 57 heavy, 85 medium/light bombers, 281 fighters. The USAAF says the airlift to China lost 149 transport aircraft in the time period.

Defiant: given its availability in 1941 it was used to equip the expanding night fighter force until twin engine types were available, Defiants leaving around mid 1942. After this came 515 squadron, formed in October 1942, the Defiants left in December 1943, Beaufighters started arriving in June 1943.

Whirlwind left 137 squadron in June and 263 squadron in December 1943.

The following is from several different reports, they do not match exactly.

To end May 1942 the USAAF reports 506 Mustang exports (73 in April, 115 in May), the British report 364 imports, the Ministry of Aircraft Production says 130 on the way, 171 in its hands, there were 21 lost at sea. Leaving 172 to be accounted for. The numbers in MAP hands is an indicator of the delays introducing a new type.

Deliveries to the RAF before March 1942 not given, March saw 20, April was 52, May was 57 Mustang, total 129, the RAF in Britain reports 120 Mustang on strength on 28 May 1942 (99 in squadrons, 11 OTU, 3 in miscellaneous units, 7 under repair) Interestingly 19 are reported as being in the process of export from Britain, ultimately 4 to USSR. 41 group reports no Mustang in its Maintenance Units on 29 May.

Also on 28 May the Middle East had 810 operational aircraft, including 3 Beaufort, 24 Beaufighter (day) plus 22 (night), the operational single seat fighter force was 165 Hurricane II, 107 Kittyhawk, 70 Spitfire V and VI, 60 Tomahawk.

First Mustang operational sortie on 10 May 1942, another 4 on 14 May, 3 sorties on 21st and 3 on 23rd, all from 26 squadron, next Mustang operations, 2 sorties a day 28 June to 4 July (except 2nd July) by 239 squadron on the 28th and 268 squadron on the other days. Another 6 pairs of sorties 5 to 11 July by 268 squadron, daily operations 12 to 17 July, by 26, 239 and 268 squadrons and so on.

Vigorous convoy 11 to 16 June, by which time there had been 11 Mustang operational sorties, low level "Offensive Reconnaissance". Hard to have an operational Mustang squadron or two in the Middle East in mid June 1942 with pilots trained in air combat as a priority.

19 August, Operation Jubilee 26 squadron 16 sorties, 5 losses, 239 squadron 14 sorties, 3 losses, 1 Fw190 claimed destroyed, 400 squadron 24 sorties, 1 loss, 414 squadron, 17 sorties, 1 Fw190 claimed.

According to the RAF census, operational units, 31 December 1943

ADGB
Beaufighter 2 Ic, 4 If, 2 IIf, 3 VIc, 104 VIf
Hurricane 22 I, 1 IIa, 3 IIb, 2 IIc, 61 IV
Mosquito 83 II, 5 III, 39 VI, 45 XII, 50 XIII, 1 XV, 9 XVII
Spitfire, 4 I, 35 IIa, 8 IIb, 3 Va, 436 Vb, 52 Vc, 9 VI, 35 VII, 46 IX, 60 LF.IX, 45 XII, 4 XIV
Typhoon, 2 Ia, 266 Ib
Whirlwind 13 I
Mustang 57 I

2nd TAF
Hurricane 13 I, 4 IIb, 44 IV
Mosquito 3 II, 5 III, 83 VI, 4 PX.IX, 1 PR.XVI
Spitfire 1 Va, 64 Vb, 14 Vc, 169 IX, 127 LF.IX, 5 PR.III, 22 PR.IV, 21 PR.XI, 4 PR.XIII
Typhoon 133 Ib
Mustang 96 I, 58 Ia, 15 III

Losses 210 Mustang I (plus 22 lost at Sea, 4 to USSR), 12 Ia. The 50 Mustang II were split 3 with a miscellaneous unit in ADGB, 1 with 41 Group, 9 with Controller of Research and Development, 40 in assembly units.

 

[ThomasP]

re

SEAAC had
31 December 1943, 1,393 Hurricane, 136 Spitfire, 184 Beaufighter, 110 Dakota
30 June 1944, 2,760 Hurricane, 469 Spitfire, 319 Beaufighter, 205 Dakota

Wow!

2,760 Hurricanes in theater as of June 1944. I knew they sent a fair number to the Far East, but that many surprises me. I realize that the FE air war was a secondary theater at that time, so it makes sense that the Hurricane would outnumber the Spitfire & such, but still . . .

Part of my surprise is maybe from a lack of coverage in literature of the Hurricane's role in the Far East (not sexy enough?), although it may be that I have just not looked into the subject enough.

If it is not too much of a hassle, does anyone know where the various Units/Sqns (in the quote above) were stationed around that time?

 

[Steamed_Banana]

re


Wow!

2,760 Hurricanes in theater as of June 1944. I knew they sent a fair number to the Far East, but that many surprises me. I realize that the FE air war was a secondary theater at that time, so it makes sense that the Hurricane would outnumber the Spitfire & such, but still . . .

Part of my surprise is maybe from a lack of coverage in literature of the Hurricane's role in the Far East (not sexy enough?), although it may be that I have just not looked into the subject enough.

If it is not too much of a hassle, does anyone know where the various Units/Sqns (in the quote above) were stationed around that time?

I have it from Shores Bloody Shambles 3, and in fact I posted the whole TO&E in the P-38 thread I think a while back, but I'll track it down and repost it later.

Of the top of my head though I think by 1944 maybe a dozen squadrons of Hurricanes were in a mix of Eastern Indian airfields, and the rest were in major cities and places Ceylon further from the front line.

 

[MikeMeech]

re


Wow!

2,760 Hurricanes in theater as of June 1944. I knew they sent a fair number to the Far East, but that many surprises me. I realize that the FE air war was a secondary theater at that time, so it makes sense that the Hurricane would outnumber the Spitfire & such, but still . . .

Part of my surprise is maybe from a lack of coverage in literature of the Hurricane's role in the Far East (not sexy enough?), although it may be that I have just not looked into the subject enough.

If it is not too much of a hassle, does anyone know where the various Units/Sqns (in the quote above) were stationed around that time?

Hi
The following may be useful for a quick comparison of changing strength/equipment in the FE during the war:

Source: 'The Forgotten Air Force - The Royal Air Force in the War Against Japan 1941-1945' by Henry Probert.

Mike

 

[MikeMeech]

Hi
The question of HF/VHF has come up on this thread in relation to the Mustang I in ACC. To take a wider view it was decided quite early, the 'Wann/Woodall' Exercise in Northern Ireland between 17 and 28 September 1940 (this was mainly an exercise to sort out signal requirements for air/army support), to use VHF for air to ground and ground to air communication. The main problem was the introduction of the equipment into service with the high demands on the VHF sets to be produced. However, by January 1941 there is a proposal of what was wanted:

Note that the VHF equipment was to be provided later. As the war went on VHF was introduced into all Theatres as the sets became available, examples of use of VHF:
Use in the Battle of Normandy;

Use in Burma;

And in Italy;

AOP did use HF when just dealing with artillery units but if they were directing CAS aircraft onto a target (as in the US 'Horsefly' system) then VHF sets were also required. The ground stations (there were variations throughout the war) had a mixture of VHF (for aircraft comms) and HF (for use connecting to ground units), as can be read in the extracts above.
It is interesting to note that US personnel who were involved in this task were trained using HF equipment in the USA then on arrival in the UK prior to D-Day they were introduced to the VHF equipment they would be using in action.
The extracts attached are from the publication 'Air Support', Air Publication 3235 (first published by the Air Ministry in 1955 and later re-printed by MLRS Books).
I hope that is of interest.

Mike

 

[ggiumarra]

The Mustang Is going into storage were primarily the very early AG series Mustang Is from the initial deliveries, those that had been issued out to Squadrons to allow them to convert onto the Mustang from Lysanders or Tomahawks. These early Mustang Is had not received the full suite of required modifications to allow them to be used operationally, except in an emergency.

I don't think it's not too much of a stretch to say that the starving out of a key island base, which is what Malta faced, if no relief reached them by late June, qualifies. They certainly rushed out every day Beaufighter they could lay their hands on, a number in deplorable condition, which accounts IIRC for a low serviceability amongst them (only 14 on Malta itself during Julius). One pilot whose unit flew to Malta at the last minute recalled their new Beaufighters had been assembled so poorly (he attributed it to them being made at a shadow factory, but I wonder if there were any of those for Beaufighters) that it was significantly slower than it should have been. A "little bit of cannibalism" to get 20, 40 or maybe even 60 Mustangs was fully justified for this operation. For Pedestal, we are talking virtually the same time period as Dieppe.

The first Mustang arrived, I believe, in October 1941, and a fair number by December, early January, so it's not as if there was no time to get acquainted with them and iron out some of the more important issues. The P-51B apparently had a pretty low serviceability rate at first, and had unresolved issues with gun jamming, as well a sometimes dangerous problem with the wheel well doors coming open in flight that did not keep them from shooting down a lot of GAF fighters on very long missions over Germany before they were resolved.

It appears Mustang Is have been "released for service in the R.A.F." with the following notices (none of which are show-stoppers, IMO, but closer to "small and niggling") as of May 1, 1942. Perhaps "released for service in the R.A.F." is a term that designates something more limited than what seems like its plain meaning; if so, you can set me straight (and I will have learned something, which I have learned a lot from the exchanges in this thread, even from those who are arguing against what I have posted).

AIR 39/110

And I would also have to dig back in my files, to see the date when the tropical service trials were completed and the Mustang I was officially cleared for overseas service in the tropics.

This is the next page from the same May 1, 1942 doc above. It actually looks as if someone has planned for and maybe is even anticipating deployment to the Med. area.

 

[ColFord]

It appears Mustang Is have been "released for service in the R.A.F." with the following notices (none of which are show-stoppers, IMO, but closer to "small and niggling") as of May 1, 1942. Perhaps "released for service in the R.A.F." is a term that designates something more limited than what seems like its plain meaning; if so, you can set me straight (and I will have learned something, which I have learned a lot from the exchanges in this thread, even from those who are arguing against what I have posted).

The 'un-modified' aircraft, lacked a range of items that would have seen their use in an operational context as having high risk. One of the things the 'un-modified' aircraft lacked was the seat back armour. So they still required installation of Mod.321 Seat Back Armour. There were also issues with the accuracy and reading of the US supplied compass, which required replacement with another type and modifications to the aircraft electrical wiring to prevent interference to the compass - something you need to conduct useful navigation over longer distances or water - Mod.301. And a few other 'niggling' issues.

The armament fixes were a little while in reaching a stage where the armament had a degree of reliability that those actually on the Squadrons and being asked to fly them considered them to be 'acceptable'. The key fixes, which involved for the wing guns, the design, testing, re-design, re-testing, acceptance and then production of the new design case and link ejection chutes and new cutouts in the wing lower surfaces commenced in June 1942 but were still being implemented and refined, final, definitive fix was only determined in November 1942. The nose guns issues, partly came down to fixes to the nose gun synchroniser wiring, better moisture protection of the nose gun synchroniser wiring, better maintenance of the nose gun synchroniser gear (plus making sure sufficient sets of the required equipment and tools for the servicing were provided); along with adjustments to the nose gun feed mechanisms and some rework of the ammunition feed paths from the ammunition bins. Then there were the issues with the original gun sight glass as supplied and the lighting of the gun sight, which led to revised gun sight head and glass and revised wiring of the lighting for the gun sight - and the pesky shortage of supply of the gun sight bulbs to match the new gun sights. 17 June 1942 the armament on the Mustang I was considered to be 'acceptable for Service use provided that the modifications listed at Appendix I are incorporated....." Then there was the delay as those modifications were designed, documented, decisions on who would conduct the modifications, getting items manufactured if required, promulgated and actually done. In the case of some of the original modifications, further refinement and rework was required.

Go into the Squadron ORBs and then see the notations on instances of armament issues, which carry through until the end of 1942 then taper off into 1943. Into 1943 they still get sufficient issues that some Squadrons still include in their post action reports where armament was used, the rounds expended and issues/stoppages/jams/gun run aways to late 1943.

And those tropical air filters, most of the early production AG serial NA-73s, the carburettor intake trunking didn't have the arrangements to actually fit the tropical air filter. The revised intake trunking was specified for the NA-83 Mustang I. NAA was to supply new upper cowling sections with the revised intake trunking, or modification kits, to fit the air filters for those aircraft that didn't have it, but they were supposed to come with the delivery of the airframe spares - later. Have yet to find in any of the surviving AM/MAP documentation if NAA actually delivered the revised cowlings or kits. In early 1944, there is a bit of a panic (someone did an audit of the Mod status of the aircraft) when it was realised that not all the surviving NA-73 Mustang Is in service or in reserve have the ability to fit the air filter element - something they will need for the upcoming invasion and they start operating from ALGs with dusty conditions. Even then, once they do get to the ALGs in France, the original type filters are not able to cope, becoming clogging and requiring more frequent replacement, rapidly reducing remaining stocks. Solution is to source a filter from another supplier offering better filtration, getting them made to the required size and specification with a high priority in quantity.

I still have not located the correspondence on the acceptance of the Mustang I for 'tropical' service, however, the November 1942 revision to the AP 2025A Mustang I Pilot's Notes is the one that includes the addition of the 'Desert Equipment' if fitted, it it not referenced in the earlier editions or revisions before then.

There was discussion about potential for the early Mustangs to be deployed or utilised overseas. IF, the RAF had been able to secure additional deliveries under Lend Lease of the NA-91 Mustang IA in sufficient numbers with delivery into later 1942 into mid-1943, then some may have been released for overseas service. (NA-91 Mustang IA: delivered NAA Aug-Sept 1942, arrivals into UK November 1942 to end January 1943). What may have happened then would be retention of the NA-91 Mustang IA in the UK and 'surplus' NA-73 and NA-83 directed overseas. Maybe.

The term 'released for service' is more limited. "Released for Service' means that the aircraft does not have handling, performance or other vices or issues that would not prevent a competent service pilot from safely operating the aircraft.

I was fortunate in my research when it started to be able to come into contact with a large number of RAF, RAAF, RCAF, RNZAF and 'other' - pilots and groundcrew (of all the supporting trades) who flew and maintained the Allison engine Mustangs during WW2. Some of those were there and flew and maintained the Mustangs when they first entered RAF service, and a smaller number were still there at VE-Day (and just beyond) still flying and maintaining them. From them I was able to obtain their first hand reminisences, but also access to pilot's log book, diaries, journals, various official and technical documentation they had retained from their time in service, hand written note books from various courses, etc. So I have been able to overlay their first hand experiences and perspectives, plus information from their preserved dcoumentation, over the surviving and publically accessible documentation through the various archives, museums and some other private collections.

 

[Geoffrey Sinclair]

General note, Colin can provide more detailed dates for Mustang equipping, operations etc.

I don't think it's not too much of a stretch to say that the starving out of a key island base, which is what Malta faced, if no relief reached them by late June, qualifies.

The planning for the operation made assumptions on what allied airfields were available, up to Gazala in North Africa.

The fundamental problem for the Vigorous convoy action 11 to 16 June, is that the US Military Attaché in Egypt was kept fully informed of the planning of the operation and its progress, he in turn informed Washington daily in a code the Axis could read. The Attaché reports combined with British Army radio discipline helps explain some of the "Battle Sense" displayed by the Axis in North Africa 1941/42. At Gazala 2 British generals communicated in Hindustani to evade unwanted listeners thereby achieving security. At Alamein the German radio interception unit was overrun, the loss of capability and the tightening of radio discipline based on understanding how much the unit could learn, along with the US changing codes made things much harder for the Axis.

They certainly rushed out every day Beaufighter they could lay their hands on,

AIR 8/511, 512, 513 Air reinforcements to Middle East/Mediterranean via Air, Takoradi and the cape, Beaufighter exports,

Week	UK to	Gibraltar	Gibraltar	to Malta	Takoradi	Takoradi	to ME
Ending	Depart	Arrive	Depart	Arrive	Arrive	Depart	Arrive
2-May-41​	16​	15​	13​	13​
9-May-41​			2​	2​
23-May-41​
30-May-41​	14​	12​	12​	12​
6-Jun-41​
13-Jun-41​	3​	3​	3​	3​
8-Aug-41​
15-Aug-41​
5-Sep-41​	6​	6​	6​	6​
12-Sep-41​	1​	1​	1​	1​
26-Sep-41​	8​	8​	7​	7​
3-Oct-41​	3​	3​
10-Oct-41​			3​	2​
28-Nov-41​	13​	13​	13​	9​
5-Dec-41​	10​	10​	7​	10​
12-Dec-41​			2​	2​
19-Dec-41​	22​	21​	8​	8​
26-Dec-41​	2​	2​	14​	14​
2-Jan-42​	3​	3​	1​	1​
9-Jan-42​	2​	2​	2​	1​
16-Jan-42​			3​	3​
30-Jan-42​	1​	1​
6-Feb-42​	13​	13​	6​	6​
20-Feb-42​	9​	9​	7​	7​
27-Feb-42​	10​	10​	9​	8​
6-Mar-42​			4​	4​
20-Mar-42​	12​	12​	4​	4​
27-Mar-42​	6​	6​	7​	7​
3-Apr-42​	7​	7​	13​	13​
10-Apr-42​	1​	1​	2​	2​	2​
17-Apr-42​
24-Apr-42​	2​	1​	1​	1​
1-May-42​					3​	2​
8-May-42​					7​
15-May-42​							2​
22-May-42​					6​	3​
29-May-42​					4​
5-Jun-42​	19​	18​	3​	1​	3​		2​
12-Jun-42​			13​	12​	2​	6​
19-Jun-42​			2​	2​	10​	1​	5​
26-Jun-42​					6​		2​
3-Jul-42​					11​	14​
Totals	183​	177​	168​	161​	54​	26​	11​

Note the gap in May. Beaufighter Exports for Australia February to June 1942 were 14, 37, 3, 7, 10, the RAF was still in the process of replacing Defiants in the home based night fighter units.

made at a shadow factory, but I wonder if there were any of those for Beaufighters)

To mid 1942 Beaufighters were made by Bristol Filton and Weston, the latter wartime, and Fairey

A "little bit of cannibalism" to get 20, 40 or maybe even 60 Mustangs was fully justified for this operation.

Simply put the Mustang was too late for squadron level operations, available in limited numbers in Britain May/June 1942.

For Pedestal, we are talking virtually the same time period as Dieppe.

In what was meant as a maximum effort, 71 sorties by 4 squadrons at Dieppe.

The first Mustang arrived, I believe, in October 1941, and a fair number by December, early January, so it's not as if there was no time to get acquainted with them and iron out some of the more important issues.

To give the detailed reports instead of just a 1941 and Q1/42 summary, remembering how many were still in MAP hands in May.

Month	Export	Import	Cumulative difference
Sep-41​	1​		1​
Oct-41​	17​	1​	17​
Nov-41​	46​	7​	56​
Dec-41​	15​	24​	47​
Jan-42​	74​	10​	111​
Feb-42​	102​	50​	163​
Mar-42​	69​	57​	175​
Apr-42​	73​	118​	130​
May-42​	115​	97​	148​
Jun-42​	64​	42​	170​
Total	576​	406​

As Colin has pointed out the problems were more protracted when it comes to dust control.

The P-51B apparently had a pretty low serviceability rate at first,

Which is the key, given convoy protection requires a lot of sorties.

and had unresolved issues with gun jamming, as well a sometimes dangerous problem with the wheel well doors coming open in flight that did not keep them from shooting down a lot of GAF fighters on very long missions over Germany before they were resolved.

The P-51 had structural failure issues into mid 1944, the operational Mustang groups claimed 9 kills in December 1943 then 44 in January 1944 and 89.5 in February, after that comes months where groups switched from P-47 to P-51 making it harder to assign claims by fighter type.

First appearance of at least one Mustang, from RAF Squadrons by Jefford

26 sqn	Jan-42​
	Feb-42​
241 sqn	Mar-42​
2, 16, 268, 613 sqn	Apr-42​
4, 225, 239 sqn	May-42​
63, 169, 170, 400, 414 sqn	Jun-42​

Trying to equate the USAAF in late 1943/early 1944 in Britain with the RAF in the Middle East in mid 1942 and the different problems they faced is a false comparison.

It appears Mustang Is have been "released for service in the R.A.F."

In short hand terms it was now acceptable to allow regular pilots to fly it, then came having trained units and combat.

Two different books give two different arrival dates for the first Mustang for testing in Britain, November 1941 or January 1942, the oil cooler was too efficient in Britain, leading to some of the oil congealing and the remaining oil running too hot, this delayed testing, new cooler tested in July 1942, the interim solution clipped 13 mph off top speed. Gun heating was a problem, armament required 17 changes, hoods needed strengthening.

It was quite standard in mid 1942 for the British to test for Desert and Tropical conditions, including survival packs.

Takoradi option, that is direct to there instead of Britain, times from arrival at Takoradi to arrival in Egypt.

First 2 Tomahawks arrived in January 1941, another 100 in the first week in February, first fly outs mid March, first arrivals in the Middle East last week in March, with 82 sent, 56 reported arriving end May.

Kittyhawk, 50 arrived mid February for 1942 AVG, all departed by week ending 3 April. First Kittyhawk for the RAF arrived week ending 22 May, first fly outs week ending 12 June. Total of 75 arrivals to week ending 5 June, by week ending 3 July there had been 64 fly outs, 42 reported arrivals in Middle East.

 

[ggiumarra]

At 1 July 1942, the RAF had 14 Squadrons, all within Army Co-operation Command that were converted over to the Mustang I. Some were considered to be 'operational' whilst others were considered to still be 'working up' and not yet operational for a number of reasons.

Of those, three Squadrons, 26 (10 May 1942), 239 (22 June 1942) & 268 (26 June 1942) had conducted operational sorties as "fully operational".

A number of the other ACC Mustang Squadrons including 2(AC), 4 (AC), 16 (AC), 225 and 613 were considered to be at an operational status, meaning that if required they could be moved to an airfield in a more forward area to commence full scale operational flying if required.

Most of those squadrons in the timeframe June-July-August 1942 were heavily involved in a range of large scale Army 'summer' exercises in the UK.

So one squadron flew a "fully operational" mission on 10 May (I was already familiar with the approximate date on that particular one) and some others did substantial training subsequently (very vaguely remembered that). Leaving aside what I pointed out before about August being the same month as Dieppe and Pedestal, is it such a crazy idea to think one or two more (total of 20-30 a/c) could have been made ready a month after the 10 May mission? The Beaufighters flew out to Malta just days ahead of time (I'd have to look up the exact date). The Mustangs would only have been needed for a couple of days starting on the 14th if they were involved in recon (in which case it's fairly unlikely they'd be using their guns anyways), and perhaps just a few-several hours if they were to supplement or replace the Beaufighters the morning of June 15, after that the "long-range" Spitfires took over and the post action report states that while they were over the convoy. Also a possibility was convoy protection late on the 14th. I would also point out that the primary benefit was making the bombers miss the ships, in which case a single functioning MG may have sufficed to throw off the aim.

UPDATE 2: I forgot to mention that it was on the morning of the 15th, before the first Spits arrived and when just 2-4 (!) Beaufighters were there (but unable to communicate with the FC on HMS Cairo bc they had the wrong kind of radios) that the tanker Kentucky (sister ship of the Ohio) and a merchant ship were fatally hit (Kentucky was only damaged but later scuttled). The Spitfires seem to have allowed no further ships to be lost, though one was lost later that morning during a brief gap in the coverage. Either some Mustangs to supplement the coverage, or more drop tanks for the Spits could have meant most if not all of the remaining convoy got through (1 merchantman was lost the day before). If 4 or 5 get through instead of just 2 (1 damaged) it could have started the snowball rolling downhill and set the stage for a positive cycle of reinforcement to further leverage the island as "unsinkable aircraft carrier." What arrived barely sufficed until Pedestal, and while more got through then, it also could have benefited from enhanced airpower on the island. As it was enough got through to bump up activity for a while, but not that much and not that long.

(Just to save you all time in figuring this out, the blue bars are Beaufighter sorties, the red, Spitfire; flight 17 or 18 was probably the last LR mission and it seems only 1-3 LR, SE fighters might have gotten lost on the way back, with 2 of the pilots rescued)

Lets take a moment to get our heads out of the weeds of feed chute pins and the standardized angle of heater installation (as important as they are) and look at the bigger picture. In 1940 and 1942 the British alone outproduced Germany in a/c by 50%. In 1941 it was 100%. They were also the beneficiaries of thousands of a/c from the US. Can anyone deny that both the UK and the US had outstanding aviation technology at that time? Yet, at a critical moment in an operation almost 3 years into a war they actually were relatively prepared for (I say relatively, as compared to, for instance, WWI) and they still can only get at most 4 fighters of dubious value in this role (yes, a terror if they got an enemy bomber in their gun sights, but terrorized themselves if enemy SE fighters show up) over a critical convoy at critical moments says to me something is wrong. To maintain they didn't realize the problem is not really supportable, because I can show you the minutes of a meeting from before the Battle of France when some very prominent names in the RAF (ones that everyone here would recognize) got together to consider this very problem (fighter protection for sea commerce) and, of course, Malta had been a hot spot for many months by now.

Now it was the British Purchasing Commission as far back as May 1940 that came up with the idea of having 170 (US) gallon tanks in the Mustang. In the second contract they increased it to 180 gallons and they also directed NAA to come up with the auxiliary internal tanks that gave the Mustang the 1750 mile ferry range (these were all revelations to me when I read them in "Bastard Stepchild", I had supposed that NAA had built the Mustang with larger standard tanks because "they didn't know they weren't supposed to" and I'd never heard of the drop-in auxiliary tanks at all). I would like to point out (and probably a lot of you know this already) that it was much more due to the fact that the Mustang was designed to carry more fuel internally than other SE fighters of its day that gave it extraordinary range (the superior aerodynamics helped some, but they were much less important). Someone, somewhere in the Air Ministry or the MAP seems to have been thinking about this role for the Mustang from the beginning (I would love to learn more about this if any of you know anything). Long-range capability is certainly not a prime capability you would think of back in 1940 if you were designing a warplane for an ACC type role (although, ironically, the one campaign it really would have come in handy was in Tunisia in the early months where the only hard surfaced airfield the Allies had was 100 miles from the front lines; send Mustangs? Uh, no, lets offload some more Hurricanes and Bisleys and send a few Mk V Spits, without, from what I can tell, any drop tanks <-- if I am wrong about the drop tanks I want to know, so don't hesitate to update me on that).

Now, if I had seen in the documents from early 1942 the idea "Hallelujah! we now have just the fighter plane to help us out at Malta and the Med! Lets do everything we can to get them there to help out as soon as possible!" that would be one thing, even if it turned out "tried as we might, we just couldn't get all the defects worked out in time". Perhaps such documentation exists, but I've never seen them and I've never seen them in the literature either; this applies all the more to between Julius and Pedestal (again, if someone knows different, I will be glad to find out about it). What we do see, however, is an outstanding fighter for just this very important role buried in a command that the RAF uniformed hierarchy don't even want to exist and which there is no conceivable chance that for many months at least will even be used for the primary role it was constituted for.

The other possibility, as I have pointed out before, was to get more long-range tanks for the Spitfires. Kenney in the SW Pac is famous for the in-theater work he did to enhance his command's a/c, not least of which was the "Brisbane Tank", but I give even more props to the RAF personnel on Malta who took leftover non-jettisonable Hurricane ferry tanks and made drop tanks out of them for Spitfires. They worked brilliantly on June 15th (when, I believe, they used all they had), otherwise it is highly likely that even the two merchant ships that (barely) made it to Malta during Harpoon would also have been sunk in which case there would have been a high probability the island would have been forced to capitulate to fend off starvation. Why can't the RAF back in the UK, with all the industrial and technical resources at their disposal, show even a measure of the resourcefulness they did on Malta? Just in case you think I'm an American beating up on the Brits, I hope it's clear by my other posts that I don't feel the AAF did all they could regarding long-range fighters either.

UPDATE: oops, I forgot this (this is in reference to tropical Spitfires, and how they may have gotten more drop tanks to Malta, and yes, even the 30-gallon type would have been quite useful):

Once again, the Mustangs could have been very helpful if they'd only sent 6-12 to do reconnaissance. It was already recognized earlier in the year that PR Spitfires were better for that job than the twin-engined bombers they typically sent out. PR Spits, however, were scarce so there were never enough to spare and they involved specialized equipment and training that were not relevant to the kind of recon needed at that time and place (meaning they were mostly not flying true PR missions), but they had the speed and range required (of course, the Mustang was faster).

There was discussion about potential for the early Mustangs to be deployed or utilised overseas. IF, the RAF had been able to secure additional deliveries under Lend Lease of the NA-91 Mustang IA in sufficient numbers with delivery into later 1942 into mid-1943, then some may have been released for overseas service. (NA-91 Mustang IA: delivered NAA Aug-Sept 1942, arrivals into UK November 1942 to end January 1943). What may have happened then would be retention of the NA-91 Mustang IA in the UK and 'surplus' NA-73 and NA-83 directed overseas. Maybe.

So one of my main points, as I expanded on some earlier in this post, is that it made no sense to relegate a very good fighter plane with some exceptional attributes to a role in which it was guaranteed to contribute almost nothing to winning the war (shooting up locomotives and barges is not going to move the needle much, especially not compared to perhaps - and I am not saying 100% it would have worked out this way, but I think it very plausible it could have - helping to shorten the time it took to drive the Axis out of N. Africa). It's a poor use of your resources.

Oh lord, this was supposed to be a concise response

 

[Steamed_Banana]

They did have some (Allison) Mustangs in the Med though, and not just A-36, right? But they don't seem to have done much with them in the fighter role, or am I mis-remembering this?

 

[ggiumarra]

They did have some (Allison) Mustangs in the Med though, and not just A-36, right? But they don't seem to have done much with them in the fighter role, or am I mis-remembering this?

From what I know, you are correct on both points.

A little bit more on what I was suggesting before and on the subject of Mustangs in the Med in mid-1943 (from a No. 14 Squadron doc, 1 June 1943, AIR 23/7323):

The RAF was also used Mustang Is off the coast of the Netherlands as fighter protection and I think recon for anti-shipping strike groups (Beaufighters serving as both torpedo bombers and Flak suppression, for which they were very effective) as well in 1943, I believe as early as the spring (I could look it up). These probably were helpful but not otherwise all that impactful, though it does again demonstrate their usefulness in the roles I talked about in previous posts relative to the Med. in mid 1942.

A couple of excerpts from a report on Op Vigorous (AIR 20/783):

I should add here that the 12 Beaufort torpedo bomber strike group was originally escorted by 2 Beaufighters which were both (I think) shot down when they ran into those 109s (for some reason it is not mentioned here).

I guess what I have absolutely failed to point out at all, much less emphasize is that more than a critique of the RAF/AAF leadership at the time I am more targeting postwar historians who dismiss the Allison Mustang as nothing more than a steppingstone to the Merlin Mustang, that really was not much different to the Allison P-40 or the P-39 and so had no particular merit as a fighter a/c. I disagree: it had plenty of performance at altitudes that were very important, especially in 1942 into early 1943 - although thanks to this thread I now understand how the P-40 had a major advantage over it in the important area of roll rate. Regardless, the main thing that set it apart and was its range. The US was not getting that in any other fighter during that time (not at all at first, and only in limited quantities through early 1943) and the British could also have made far better use of the capability they had at their disposal in the Mustang (though a lot of the missions I'm talking about could have been done nearly as well by Spitfires, which you're going to have to have around anyways, on Malta at least, so arguably a better choice, though I believe the best solution would have been both together) during some crucial months when that capability could have been very useful and potentially impactful way out of proportion to the number of a/c involved. The counterfactuals are mainly to illustrate the point. Of course, there is no way to know how their use would have affected things, especially since the opportunity for greatest impact came in a limited time frame (two days in June and less than 24 hours in August) so you're talking about situations where a little bad luck could negate everything else (I am not suggesting some sort of American Wunderwaffe here, far from it).

I also maintain it would have been better to keep the P-51A in major production until the decision was made to cease Allison SE fighter production, mostly for the range as well.

As far as a single-stage/two-speed s/c on the Allison, that would have been a very nice improvement and was definitely a fail on the AAF not to pursue that possibility, which should have paid off handsomely, but in the context of what I am talking about it's not really enabling anything the way increased range is. From a broad perspective it's just a nice cherry on top (though I suppose if I was a Mustang pilot locked in combat with an enemy fighter I might see it a little differently).

 

[Steamed_Banana]

I guess what I have absolutely failed to point out at all, much less emphasize is that more than a critique of the RAF/AAF leadership at the time I am more targeting postwar historians who dismiss the Allison Mustang as nothing more than a steppingstone to the Merlin Mustang, that really was not much different to the Allison P-40 or the P-39 and so had no particular merit as a fighter a/c. I disagree: it had plenty of performance at altitudes that were very important, especially in 1942 into early 1943 - although thanks to this thread I now understand how the P-40 had a major advantage over it in the important area of roll rate. Regardless, the main thing that set it apart and was its range. The US was not getting that in any other fighter during that time (not at all at first, and only in limited quantities through early 1943) and the British could also have made far better use of the capability they had at their disposal in the Mustang (though a lot of the missions I'm talking about could have been done nearly as well by Spitfires, which you're going to have to have around anyways, on Malta at least, so arguably a better choice, though I believe the best solution would have been both together) during some crucial months when that capability could have been very useful and potentially impactful way out of proportion to the number of a/c involved. The counterfactuals are mainly to illustrate the point. Of course, there is no way to know how their use would have affected things, especially since the opportunity for greatest impact came in a limited time frame (two days in June and less than 24 hours in August) so you're talking about situations where a little bad luck could negate everything else (I am not suggesting some sort of American Wunderwaffe here, far from it).

I totally agree with the potential merits of the Mustang I / II for this Theater. Especially a couple of units operating from Malta.

Compared to the Kittyhawk, the former had both roll and turn rate as an advantage, and the Spitfire could out-turn both of them, but the Mustang does indeed have the range as well as apparently speed by quite a margin, and I think this could have been leveraged to great advantage in the Theater. The roll rate issue could also have been fixed before 1942 I think (it was certainly fixed in the P-51B/C)

I also maintain it would have been better to keep the P-51A in major production until the decision was made to cease Allison SE fighter production, mostly for the range as well.

Agree again. I think if they had more of these in Burma and in the South Pacific it could have been very beneficial. They should have made these instead of about half of the P-39s they made (the other half going to the Soviets).

As far as a single-stage/two-speed s/c on the Allison, that would have been a very nice improvement and was definitely a fail on the AAF not to pursue that possibility, which should have paid off handsomely, but in the context of what I am talking about it's not really enabling anything the way increased range is. From a broad perspective it's just a nice cherry on top (though I suppose if I was a Mustang pilot locked in combat with an enemy fighter I might see it a little differently).

A two speed SC would have greatly enhanced it's performance. Given the speed it was making on the Allison, if it had say 1,100 or 1,200 hp at 20,000 feet I think it would have been an absolute beast.

 

[Elan Vital]

I recall NACA testing the German variable speed supercharger drive, a single and 2-speed Szydlowski-Planiol supercharger with swirl throttle along other supercharger/turbocharger types.
Was there any thought given to making an Allison supercharger out of one of these types?

That was in 1940 it seems. Here: NACA report

 

[ColFord]

So one squadron flew a "fully operational" mission on 10 May (I was already familiar with the approximate date on that particular one) and some others did substantial training subsequently (very vaguely remembered that). Leaving aside what I pointed out before about August being the same month as Dieppe and Pedestal, is it such a crazy idea to think one or two more (total of 20-30 a/c) could have been made ready a month after the 10 May mission?

No.26 Squadron RAF, on 10 May 1942, Flying Officer G N Dawson RAFV flew NA-73 Mustang I AG418 on a SOLO 'offensive reconnaissance' from RAF Gatwick to Berck-sur-Mer in France, where he strafed a hangar at the aerodrome there, then proceeded to strafe a flak position near Rang-du-Flier, and a train with ten enclosed carriages near le Fresnesie before returning safely to base. So not at Squadron strength, a solo sortie, a quick dash over the Channel, just over the coast, shoot up some targets of opportunity and get out quick. No.26 Squadron flies their next sortie on 14 May 1942, comprising two Mustang Is, again another quick dash across the channel, not penetrating far in over the coast, in fact less so than most of the Spitfire and Hurricane units flying Rhubarbs and Rangers over France at the time. On 18 May a number of the Squadron pilots head up to Abbotsinch to collect modified Mustangs, un-modified Mustangs are flown out. On 19 May the Squadron commences participation at Squadron strength in Exercise TIGER, which continues until 31 May. During that time, pairs are sent out 21 and 27 May for Rhubarbs just over the French coast. In the middle of the Squadron's participation in Exercise TIGER, pilots are sent to Abbotsinch to collect modified Mustangs on 22, 25 and 27 May. At the conclusion of Exercise TIGER the Squadron then has one day for the ground crew to conduct maintenance, including on the newly arrive modified Mustangs, before they commence a program of air firing and air tests on the newly received modified Mustangs during June. Also during June, No.26 Squadron 'loses' half it strength which is split off to form the core of the newly forming No.171 Squadron, and receives an influx of new pilots fresh from 41 OTU, a suffered a period where there is a shortage of groundcrew familiar with the Mustang until new personnel are posted in and trained up. The shortage of trained ground crew is repeatedly noted in unit and WIng ORBs along with its impact on the rate of flying able to be achieved. Next operational sortie is then not until 7 July 1942, first POPULAR sortie along a segment of the French Coast by a pair of Mustangs as a 'demonstration' - basically a live rehearsal to prove the methodology and camera installation works. On 14 July they send out three Mustang Is on the first full operational sortie and lose one out of the three - likely flak. On 17 July then send out three on another POPULAR and lose two out of the three. In all cases, the pilots lost are amongst those that arrived in June, fresh from 41OTU.

In the timeframe May through July 1942, the ORBs for all the Mustang Squadrons considered to be 'operational' at that time are recording the transition out of unmodified Mustangs and the collection or delivery of modified Mustangs. Now when each of those modified Mustangs arrived at the Squadron, they then needed a degree of work by the Squadron's ground crew to fully bring the aircraft up to a state to be considered fully operational. Radio equipment would need to be checked, tuned for the Squadron and local sector frequencies; armament checked, usually a couple of sessions in the butts to check armament alignment and harmonisation, followed by test firing in the air and further checks and fixes for any issues identified; compasses would be swung; usually the fitters and riggers would find a couple of things that needed adjustment or fixing; then conduct of any of the required modification that were not the responsibility of MAP but were to be done at unit level. If the aircraft was destined to carry an oblique F.24, then it would then have to be sent away again for a few days to have the camera modifications conducted. Plus paint on the Squadron ID letter and individual aircraft id letter.

Consider this, the two RCAF Mustang I Squadron, No.400 and 414, had not flown an operational sortie using their Mustangs before Dieppe. Their first operational sorties, for a large number of the pilots, on Mustangs, was Dieppe.

The RAF was also used Mustang Is off the coast of the Netherlands as fighter protection and I think recon for anti-shipping strike groups (Beaufighters serving as both torpedo bombers and Flak suppression, for which they were very effective) as well in 1943, I believe as early as the spring (I could look it up). These probably were helpful but not otherwise all that impactful, though it does again demonstrate their usefulness in the roles I talked about in previous posts relative to the Med. in mid 1942.

Yes, a number of the RAF Mustang I Squadrons flew shipping reconnaissances - Jim Crow or Lagoon - starting from 29 June 1942 (most sorties before then were Rhubarbs or Populars along the French or Belgian coasts) from basically up near Borkum on the mouth of the Ems, down around the Dutch coast, particularly a couple of 'beats' covering from around Terschelling or Texel down to The Hook; then others covering from around Boulogne to Ushant. The Mustangs would go out a couple of times during the day, often pairs that had some guidance about possible 'trade' likely from Ultra and other sources. Sometimes it would be two pairs, who would fly out to a mid-point, with one pair covering the southern half and the other the northern half of the 'beat'. They would locate, identify course and speed and composition of the convoy and report so that Coastal Command and RN Light Forces could then decide the best response. A number of the ACC Mustang Squadrons also flew escort for RN Light Forces at dusk - as they were deploying for the night's work - and dawn - as they were returning - and got involved in few intense dogfights as a result - 2nd half of 1942 to late 1943. On a number of occasions as well they were tasked for dawn sorties chasing German E-Boats and fast minelayers as they had been out during the night and heading for their home ports.

In August 1942, a couple of the ACC Mustang Squadrons start flying fighter affiliation with the Bostons and Venturas of RAF 2 Group, focussing on low level flying, defence and attack. That then builds into September 1942, with large scale practices at Squadron level of Mustangs protecting a full Squadron of Bostons or Venturas, then eventually multiple Mustang Squadrons and multiple 2 Group Squadrons - exercises included the Mustangs 'protecting' the bombers at low level from 'attacking' Spitfires, Typhoons and Whirlwinds. That culminated in an operation on 16 September 1942 when eleven Mustang Is (was to be 12 but one went u/s) of No.268 Squadron RAF escorted 12 Bostons of No.88 Squadron on a low level attack against a concentration of enemy shipping at Den Helder - which had been spotted by a No.268 Squadron pair doing the morning 'Lagoon'. The operational plan was for the Mustangs to provide a low escort to the Bostons with a Squadron of Spitfires slightly higher escorting them out part of the way then turning back, and being met by a Squadron of Spitfires on the way back - neither Spitfire Squadron made the RV. The ACC Mustangs were tasked with providing escorts to a number of operations at low level with 2 Group until mid-1943, including the attack on the Phillips works. There was a degree of friction between HQ ACC, the ACC Mustang Wings and Squadrons and Fighter Command over the use of the Mustangs in the low altitude bomber escort role for 2 Group. They were trying to get the Mustangs to use tactics that were more in line with what the Spitfire Squadrons were using and that didn't take best advantage of the Mustang's low altitude performance. The positive feedback on the escort being provided by the ACC Mustangs to the 2 Group bombers on low level operations did not go down well with some in FC. In particular 2 Group noted the Mustangs turned up to the RV on time, at the right location, stayed down low with the bombers - didn't drift up higher where they would get picked up by the enemy radar - maintained excellent R.T discipline, and they didn't 'drift off' too far away from the bombers. Post action reports written by a couple of the senior ACC staff regarding operations where the 2 Group bombers suffered high loss levels because the FC fighters turned away early due to low fuel, didn't make the RVs for either the ingress or exit and pursued enemy fighters too far away leaving the bombers unguarded allowing other enemy fighters to attack, led to FC sidelining the ACC Mustang Squadrons from those types of escort operations.

The other area where the performance of the ACC Mustangs was called in by FC in the UK was against the low level Luftwaffe Jabo attacks against south east England from mid 1942 onwards until end 1943. They also used the ACC Mustangs for dawn and dusk low level patrols off the coast against low level German mine laying aircraft.

A little bit more on what I was suggesting before and on the subject of Mustangs in the Med in mid-1943 (from a No. 14 Squadron doc, 1 June 1943, AIR 23/7323):

Six NA-97 A-36A provided by the US 12th AAF in July 1943 for use by No.1437 Strategic Reconnaissance Flight after their Marylands were basically plain worn out and no longer viable in the operational environment. Were used by the flight for the invasion of Sicily and southern Italy, up until late October 1943, surviving aircraft - a couple - handed over to help prepare RAF P-40 units converting to Mustang III.

No.14 Squadron RAF, four USAAF NA-91 P-51 supplied 'on loan' by US 12th AAF, April to June 1943. Six single seat fighter pilots to fly them provided by RAF fighter Squadrons in MTO. Issues with serviceability and spares noted as limitation on number of sorties being able to be flown.

No.225 Squadron RAF, four USAAF NA-91 P-51 supplied 'on loan' by USAAF 12 AAF, mid April 1943 to mid July 1943. The US P-51s were fitted with a single vertical reconnaissance camera in the tail. No.225 Squadron at the time only had five Spitfire Vb/c on their strength fitted with a single F.24 oblique mounted just behind the cockpit in the radio hatch. They needed the vertical camera to get specific types of required photography, and to be able to take photos outside the effective range of light flak. Use was basically over by mid May with German & Italian surrender, then only one sortie flown mid June over Pantelleria and Lampedusa Islands. Arrival of PR Spitfires and more Spitfire Vb/c fitted with cameras and ability to also carry slipper tanks for the Squadron from late June removed requirement for the Mustangs, so returned to USAF. Supply of spare parts, serviceability and unfamiliarity of groundcrew with the Mustang limited rate and number of sorties flown, recorded in Squadron ORBs.

There is a lot more to the story, and unfortunately a lot of it has not been 'out there' to inform people of what the actual historical facts were.

 

[Shortround6]

Using non-standard aircraft in small numbers in far-away theaters often results in a lower than normal serviceability rate.
British sent a report to the US on a 150 test done on Kittuhawk I (?) and while the plane completed the test "in a very satisfactory manor"
as a whole one of complaints was "..all the pipeline joints on all systems are secured with American type clips" Which didn't seem to work as well as the British clips and needed more checking and tightening.
Hopefully the Allison Mustangs used the same types of pipeline joint clips as the P-40s and needed "spares" were not thousands of miles away, only a few hundred?
Things like landing gear door actuators or emergency hydraulic system parts may be specific (or require adaptation) from anything else in inventory.
Ventral mount radiators/oil coolers tend to suffer from foreign object ingestion.

As mentioned by others above, Many of the ground crew of the first Mustang squadrons were just learning how to maintain them. Squadrons in the UK might be able to post men back and forth or communicate on certain problems fairly quickly. Several squadrons in the Med would be more isolated.

None of this might be deal breakers but by the spring and summer of 1942 the British had all too many examples of sending small numbers of odd aircraft (and tanks and guns and trucks and.....and ......and.....and) to faraway places and having to then try and deal with the logistics of keeping them running or in combat.

 

[Geoffrey Sinclair]

26 October 1940 NA-73X first flight
25 August 1941 XP-51 41-38 accepted
27 August 1941 first NA-73 accepted for Britain.
25 September 1941 contract DA-140 for 150 P-51 Mustang
31 December 1941 XP-51 41-39 accepted.
January 1942 RAF decides the P-51 is the right choice for tactical reconnaissance units, replacing Tomahawks.
Last real chance to change the Curtiss contract from P-47 to P-51
31 January 1942 contract AC-24545 for P-47G from Curtiss

10 May 1942 First Mustang operational sortie, another 4 on 14 May, 3 sorties on 21st and 3 on 23rd, all from 26 squadron, next Mustang operations, 2 sorties a day 28 June to 4 July (except 2nd July) by 239 squadron on the 28th and 268 squadron on the other days. Looking at the 26 squadron records they were flying Tomahawk and Lysander in May 1942 alongside their Mustang.

11 to 16 June 1942, Vigorous convoy, full details known to the axis in advance.

As of end July Mustang production will cease in September 1942 unless new contracts are written. Leaving the RAF with its 320+300+150 less losses at sea and to the USAAF, or about 2 months of average Spitfire production in 1942.

7 August 1942 AC-27396 500 A-36A intended for USAAF.
24 August 1942 AC-30479 1,200 P-51, However the number of Allison versions is to be minimised, Merlin production split between the RAF and USAAF. The RAF does not seem to have asked for any Allison Mustang from this contract but was allocated 50 as compensation for USAAF allocations from earlier contracts.

24 September 1942 first P-47G acceptance from Curtiss, next 2 on 31 October, next 2 on 30 November, then 1 on 31 December.

30 September 1942 final P-51 acceptances from DA-140.
13 October first flight of Mustang X
14 October first A-36A acceptance, another 30 on the 28th to 31st, 10 more 25th to 30th November, with 101 accepted in December

30 November 1942 XP-51B first flight.

28 February 1943, cumulative RAF Mustang I losses 3 instructional, 87 category E, 16 lost at sea, 4 USSR, total 110 out of 620 sent, no losses from the 93 Mustang Ia.

30 June 1944, Mustang I, 616 for RAF, losses 9 instructional, 252 Category E, 22 lost in transit, 4 to USSR, 6 census queries, leaving 323 effectives, Mustang Ia 33 category E, 1 census query leaving 34 effectives, Mustang II 4 category E leaving 46 effectives. (4 Mustang I converted to Mustang X, 3 with RAF, 1 with USAAF)

A-36 with USAAF peaked at 445 in February 1943, down to 226 in December, 120 in June 1944, 37 in December. The RAF would be well aware how quickly strength eroded for operational aircraft.

So one squadron flew a "fully operational" mission on 10 May

No, one Mustang flew 1 sortie, a shallow penetration of French airspace.

Leaving aside what I pointed out before about August being the same month as Dieppe and Pedestal, is it such a crazy idea to think one or two more (total of 20-30 a/c) could have been made ready a month after the 10 May mission?

The short answer is yes, it is a crazy idea, given the reported problems including compass and armament, along with trained pilots and the problems of having spare parts to support several days of intensive operations, note the reported decline in Beaufighter serviceability, Dieppe, 71 sorties 9 losses, 12.67%, by 4 squadrons, including 2 squadrons flying their first operations

The Beaufighters flew out to Malta just days ahead of time (I'd have to look up the exact date).

Please do so, given the week ending data is obviously not precise enough.

Lets take a moment to get our heads out of the weeds of feed chute pins and the standardized angle of heater installation (as important as they are) and look at the bigger picture.

Irrelevant to getting and maintaining an operational Mustang fighter/reconnaissance force in Malta June to August 1942.

n 1940 and 1942 the British alone outproduced Germany in a/c by 50%. In 1941 it was 100%. They were also the beneficiaries of thousands of a/c from the US.

Production, 1940 to 1942
Britain, 15,049, 20,094, 23,672 UK Statistical Digest
Germany, 10,826, 11,776, 15,556, USSBS
140%, 170%, 150%.

Italy 3,257, 3,503, 2,813

From North America direct to Britain + direct to overseas, including Canada etc., 1,069+0, 1,712+2,761, 2,394+3,504. The figures exclude 214 aircraft on pre war contracts delivered September 1939 to February 1940 and also exclude 284 trainers delivered to Canada before June 1942. UK Statistical Digest.

Can anyone deny that both the UK and the US had outstanding aviation technology at that time?

On average what the allies were turning out were not as good as the latest Bf109, Fw190, Ju88 for example.

I can show you the minutes of a meeting from before the Battle of France when some very prominent names in the RAF (ones that everyone here would recognize) got together to consider this very problem (fighter protection for sea commerce) and, of course, Malta had been a hot spot for many months by now.

Please provide the reference and details, in particular where the ships were expected to be relative to land. Remember the RAF had little air sea rescue systems and fighters did not carry dinghies. Britain relied on coastal shipping from 1939 to 1945, 3,584 FN/FS series with 104,792 ships, 1940 to 1944 531 CW/CE convoys with 9,097 ships, 1941 to 1944 1,067 WP/PW convoys with 16,546 ships. Even during the Battle of Britain shipping protection made up a significant amount of RAF fighter sorties.

Now it was the British Purchasing Commission as far back as May 1940 that came up with the idea of having 170 (US) gallon tanks in the Mustang.

A legacy from F.18/39 which begat the MB.3/4/5, tankage for a 2,000 HP engine, 15 minutes take off power allowance, 2 hours economic cruise, 15 minutes full power combat, 30% reserves. It was the most modern British single seat single engine specification.

The F.18/37 Typhoon had 114 imperial gallons internal fuel, the early P-51 150 gallons. The Mohawk and early Tomahawk 132 gallons.

it was much more due to the fact that the Mustang was designed to carry more fuel internally than other SE fighters of its day that gave it extraordinary range (the superior aerodynamics helped some, but they were much less important).

The superior aerodynamics gave the internal wing space to carry the fuel load with reduced drag, it gave the P-51 about 10% better top speed than the Spitfire with the same engine, that in turn enabled a lower power engine with corresponding lower fuel consumption. The Spitfire I was about 10% faster than the Hurricane I with the same engine, the Hurricane could go 103.5 miles on 100 pounds of fuel, the Spitfire 118.8.

Someone, somewhere in the Air Ministry or the MAP seems to have been thinking about this role for the Mustang from the beginning

No, they had the Lysander for the role, making lots of them, the RAF was providing more tactical reconnaissance squadrons than the army had field forces to use them in 1938/39. F.18/39 is quite explicit, top speed at 15,000 feet, two speed supercharger so speed below 15,000 feet be as high as possible. Look through the early war RAF fighter performance charts and 15,000 feet is the common test altitude. The Battle of Britain pushed thinking into the 30,000 feet or higher ideas. The Battle of France pushed thinking into the need to fight for tactical reconnaissance, hence the allocation of Tomahawks in 1941, then came a superior alternative in 1942.

Uh, no, lets offload some more Hurricanes and Bisleys and send a few Mk V Spits,

Welcome to the reality the forces in Britain had the theory of combined operations, the forces in the Mediterranean the reality. A situation that continued until the second half of 1944. A few Spitfires translates to 758 to the Mediterranean October 1942 to February 1943, plus 138 to North Africa, then 380 to North Africa March and April 1943, including mark VIII and IX.

What we do see, however, is an outstanding fighter for just this very important role buried in a command that the RAF uniformed hierarchy don't even want to exist and which there is no conceivable chance that for many months at least will even be used for the primary role it was constituted for.

Pre war the RAF understood the need for Army support, as did the Army for Air support, how that was done remained a big difference. A 1943 invasion of France was quite live in 1942, the US kept insisting on it.

The other possibility, as I have pointed out before, was to get more long-range tanks for the Spitfires.

All you need to do is provide the shipping space for high volume low weight items that would be regularly lost on operations.

Kenney in the SW Pac is famous for the in-theater work he did to enhance his command's a/c,

Pays to have a local industrial base able to make things.

Why can't the RAF back in the UK, with all the industrial and technical resources at their disposal, show even a measure of the resourcefulness they did on Malta?

They were making the tanks, what they needed was the shipping space. According to Lloyds the first 28 months of the war saw 7,594,305 GRT of allied merchant shipping lost, in 1942 it was 7,377,351 GRT. Getting the most out of the available shipping "full and down" took a while as the cargo mixture changed so much.

Compounding the losses was the lack of a proper US Army shipment control system. In mid 1942 an example given was one ship 30% of the cargo had no markings, 25% no addressee and just general description, e.g. Quartermaster. In September 1942 the equipment of 1 infantry regiment was sent to England split up between 55 ships. The result was although the equipment was in England for the US troops already in England allocated to Torch some of the equipment had to be sent a second or even third time because it became lost somewhere in England.

it made no sense to relegate a very good fighter plane with some exceptional attributes to a role in which it was guaranteed to contribute almost nothing to winning the war

Eisenhower was appointed to command Torch on 14 August 1942, then comes how long the operation was intended to take, the US was insisting on an invasion of France in 1943. Apart from the optimism about when US forces would be ready the shipping losses in 1942 resulted in mass cancellation of LST orders in September 1942 to allow DE construction. Then came the mass cancellation of DE orders in September and October 1943 to allow LST construction followed by further DE cancellations in 1944 while turning a number of DE into APD as part of the amphibious forces. Or another way the US completed 61 LST in January 1943, then another 229 for the rest of 1943. Landing craft issues delayed Overlord to June, and cancelled Anvil as a simultaneous operation.

If you want an "efficient" use of "a few" P-51 on sustained operations over water but close to land consider anti submarine reconnaissance sorties around where the merchant ships were being lost. In the December 1941 to May 1942 period the allies lost 1.85 million tons of tankers, and another 750,000 June to August mainly off the US coast and in the Caribbean. Allied tanker tonnage went backwards to at least December 1942 and it took until the end of 1943 to get back to the end of 1941 position. After that the gains were more than a million tons per quarter more than the losses. Even so to help ease the shortage tankers were allowed out of convoy when crossing the Atlantic in 1944. Try and run intensive air operations without bulk fuel supplies.

During 1942 the RAF wanted fighters with performance at 20,000 feet or higher. It knew what Allison Mustangs it had would be about all it was going to get which meant the force would quickly become numerically irrelevant with sustained operations. Note how quickly the A-36 force dwindled.

but I think it very plausible it could have - helping to shorten the time it took to drive the Axis out of N. Africa). It's a poor use of your resources.

Since we are into counter factuals, allied anti shipping does so well the axis cut their losses in North Africa in late 1942, evacuating the personnel, no 250,000 prisoners in Tunisia with associated army and air force equipment losses. Those forces then need to be defeated in Sicily etc.

I guess what I have absolutely failed to point out at all, much less emphasize is that more than a critique of the RAF/AAF leadership at the time

It does not come across like that.

I am more targeting postwar historians who dismiss the Allison Mustang as nothing more than a steppingstone to the Merlin Mustang, that really was not much different to the Allison P-40 or the P-39 and so had no particular merit as a fighter a/c.

Name the historians instead of coming up with a few right forces at a few right times could do wonderful things. The RAF could keep the Allison Mustang in England for the most important operation, Overlord, where they would be facing a much more numerous Luftwaffe than in the Mediterranean or could use it in the Mediterranean from late 1942 through 1943 once the supply lines had been established and find something else for Overlord, running into the Mustang shortage the 9th Air Force reported and forced it to switch a P-51 group to P-47 for about 3 months.

Of course, there is no way to know how their use would have affected things, especially since the opportunity for greatest impact came in a limited time frame (two days in June and less than 24 hours in August)

Firstly that is handing the allies some remarkable predictive powers, secondly assuming that the allies had the relevant forces available to operate out of Malta safely in the second half of 1942 with adequate supplies and thirdly given the actual losses the Axis took how much more before they give up?

 

[drgondog]

Couple of comments re: P-51 vs P-39 and P-40 and P-38G and P-47B
Tactical Trails at Eglin Proving Ground Aug 7 -Nov 7, 1942
Summary statement "This airplane (P-51-NA) superior to all other types up to 15,000 feet"
Below 15000 feet:
Speed - superior to all types
Climb - superior to P-39D, P-40F, P-47B
Turn - equal to P-40, P-39, better than P-38F and P-47B
Roll - slightly inferior to P-40F, superior to P-39, P-38 and P-47.
Dive - better acceleration and top dive speed than all others tested.

Note, the P-51 was 400 pounds heavier than XP-51/Mustang I/A-36/P-51A due to the 4x20mm cannon inst'l and was 'draggier due to both the cannon installation and also induced drag due to higher weight. Also note that the P-40 remained a 'better roller' than all versions of the P-51, below 250-280mph TAS but all versions of P-51 could extend rather than fight due to much higher speed envelope for both level flight and dive. Only the P-47B was equal in dive, but also structurally deficient at near terminal dive speeds - but it was lighter than the P-47B/C with same HP until water injection introduced in the D-11.

Notes about P-51 design issues leading to structural failures:
Loose latches on main gear door fairing, which resulted in opening due to aero loads.
Inadequate up-lock for main gear, causing gear to crash through the fairing door in high g/high aero loads,
Ammo door failure due to very high speed aero induced loads.
Empennage failure due to severe asymmetric loads with several inputs causing the failure due to large rudder deflections in roll and coupled with yaw and high prop vortex strength.
Several instances of engine mount bolt structural failure in mid-March 1943 due to faulty heat treatment by NAA subcontractor.

Fixes:
Beef up latches and up-lock.
Stiffen ammo door.
Introduce dorsal fin and reverse rudder boost tab, then change angle of incidence for H.Stab and introduce metal elevators.
Introduce improvements to contractor part QA for critical components.

 

[drgondog]

Now it was the British Purchasing Commission as far back as May 1940 that came up with the idea of having 170 (US) gallon tanks in the Mustang. In the second contract they increased it to 180 gallons and they also directed NAA to come up with the auxiliary internal tanks that gave the Mustang the 1750 mile ferry range (these were all revelations to me when I read them in "Bastard Stepchild", I had supposed that NAA had built the Mustang with larger standard tanks because "they didn't know they weren't supposed to" and I'd never heard of the drop-in auxiliary tanks at all). I would like to point out (and probably a lot of you know this already) that it was much more due to the fact that the Mustang was designed to carry more fuel internally than other SE fighters of its day that gave it extraordinary range (the superior aerodynamics helped some, but they were much less important). Someone, somewhere in the Air Ministry or the MAP seems to have been thinking about this role for the Mustang from the beginning (I would love to learn more about this if any of you know anything).

Not entirely sure regarding the driving force to include 170-gal internal fuel in NA-73.

For example, for the contemporary (1940) US Pursuit, XP-39 and YP-39 each had 200-gal. The P-40A had 180-gal and the P-40B had 160-gal. The YP-38 had 400-gal, or 200-gal per engine. The P-509 was proposed with 157-gal and the XP-46 with 156-gal. The first delivered NA-73X spec in April 1940 had 157-gal but the spec morphed to NA-73/XP-51 in two weeks to 170-gal self sealed tank.

I do know that RAF was keeping NAA design team well informed regarding XP-46 design branches after Atwood acquired the P-40 and P-46 data from Burdette Curtiss in April 1940.


That said, the BPC/RAF were insistent that the fuel tanks be protected from the outset and none of the flying US Pursuit aircraft had armor plate or self sealing tanks. The Mustang I tested to 1020mi 'yardstick' range with zero reserve at 65% power cruise for 15,000 feet.