What was the RNZAF's Mustang order?

[ZacYates]

Hi folks,
How many Mustangs did we order during WW2, and which subtype/s were they?

Wikipedia says this, citing Stewart Wilson's Mustang Warbirds: Civil Registered Mustangs of Australia and New Zealand Then and Now: "New Zealand ordered 370 P-51 Mustangs to supplement its F4U Corsairs in the Pacific Ocean Areas theater. Scheduled deliveries were for an initial batch of 30 P-51Ds, followed by 137 more P-51Ds and 203 P-51Ms."

In another thread on this forum I found this from David Duxbury:

May 16, 2020 23:58:46 GMT 12 davidd said:

Interesting detail was that apart from the first 30 aircraft, all the Mustangs on allotment were P-51Ms; however despite the designation, these were in fact very similar to P-51Ds apart from model of the Packard Merlin fitted.

I'm wondering if somehow P-51M was a misprint for something else because the M is a development of the lightweight P-51H - a very different beast to the Ds we received - or if David was misinformed.

The background info for the Mustang on Phillip Treweek's excellent Kiwi Aircraft Images also says the order was for 370 without any subtypes mentioned.

When announcing on Facebook that NZ2423 was joining the Biggin Hill collection Brendon Deere said the order was for 160 Mustangs. His first Military Wings book only states "the original large order was cut to a fraction".

Ewing and Macpherson's The History of New Zealand Aviation says at war's end the government cancelled "allotments" for "137 North American Mustang fighter/bombers".

Gavin Conroy's Precious Metal says 320.

I'm sure Mustangs of the RAAF and RNZAF by a certain forumite could be a help but unfortunately I don't have access to a copy.

In the scheme of things it's a fairly minor nit to be picking but I'm curious, particularly as to whether we had in fact ordered any P-51Ms.

[baz62]

In my copy of Southern Cross Mustangs it says: NZ Government approached the Munitions Assignment Committee(Air) seeking allocation of 167 to be ordered with a further 203 for delivery in mid 1946. MAC(Air) assigned batch of 30 Dallas built P51D-25-NT with the balance to be made up of P51M-1-NTs. I wonder if that was supposed to say P51D-1-NT?

[joey05]

From the oh so reliable wiki

P-51M (NA-124)
The P-51M-1-NT was based on the P-51D-30-NA/NT, but utilized the V-1650-9A engine lacking water injection and therefore rated for lower maximum power than the -7. One was completed out of the original 1629 ordered, AAF Serial Number 45-11743.

[markrogers]

I read a long time ago (25 years ago) that the P-51M also had twin aerials on top of the rear fuselage, similar to the ones on the Mustangs that were escorting the B-29s to Japan.

[madmac]

I wonder if there are any tech pubs (AFM's, etc) for the P-51M that made it in to the country.

[davidd]

A couple of small points:

New Zealand never actually ordered any Mustangs, they were allocated by the Munitions Assignment Board in Washington (actually the Munitions Assignment Committee [Air] of that Board), based on bids from the theatre commander under which the RNZAF served in the forward area. That is a part of how "Lend-Lease" actually worked.

Although slated for mass-production, as is pointed out above, only one was ever actually completed. I don't know if any tech publication was actually produced for the P-51M, probably not, but if it had, it may have been a simple supplement to the P-51D Tech Orders as they were practically identical to the later P-51Ds (as noted by joey5 above).

David D

[baz62]

Possibly should have said "asked for" rather than "ordered"?

[tbf2504]

From some gleaning of air files in archives some time ago, I saw a reference to the impending change to Mustangs and a move to USAAF type of aircraft that there was thought that it would
allow the RNZAF to become part of the general move through the Philippines onto Japan as part of MacArthur's campaign. The reasoning was that US Navy aircraft (Corsairs) may have logistical support
problems in his theatre of operations.

[davidd]

I don't think that "asking" for any particular aircraft type would have done any good - without the concurrence of the theatre commander we would not have got any aircraft at all, or at least only types that no other theatre commander wanted! The first thing any country had to do to obtain military aircraft (and particularly modern ones) was to undertake to train up squadrons of aircraft (suggest types, such as SS fighter, medium bomber, Anti-submarine patrol aircraft), and the powers that be in Washington (although earlier in the War, London was where you might send your suggestions) would have to be approached on the subject, and we might receive reply that the logical theatre for the RNZAF would be the South Pacific theatre of operations. After the (American in this case) theatre commander had perused New Zealand's suggestions and decided how he could use such squadrons, he would then put his aircraft bids (including proposed RNZAF units) to the Munitions Assignment Board for general agreement, thence to the Munitions Assignment Committee (Air), who would have to deliberate on each theatre, then sit down to the difficult task of attempting to fairly allocate the types of aircraft suggested by all the theatre commanders around the World. For each year of the war (and with many intervening reviews of projected and revised production schedules, viewed in conjunction with an overall assessment of the progress of the war in various theatres, and expected developments), this committee had to evaluate the claims against projected production and try to make fair allocations to all claimants. To even be considered for aircraft (or anything else for that matter), most claimants (such as the RNZAF, or more accurately their theatre commander) would have to submit a plan on the proposed deployment of the allocated aircraft, usually viewed for convenience as operational squadrons fully equipped, plus allowances for attrition aircraft based generally on recent operational experience applicable to each theatre and the type of aircraft concerned. Fighter aircraft were considered more likely to be lost, compared to, say Catalina patrol aircraft. The Catalinas were, by middle of the war, only used operationally at night, or with fighter escort when required to operate in areas patrolled by enemy fighters, and enemy warships were usually left to combat aircraft to deal with. Like many smaller air forces, the RNZAF operational squadrons were to be generally at the disposal of the theatre commander to which they had been assigned, although allowances had to be made for a "working up" period in New Zealand on each new type, plus further operational training in the rear Pacific bases in concert with American air force elements so as to learn their general operating procedures, formations, drills and language, as well as their paper work! Of course once the first RNZAF squadrons had been blooded (completed an operation tour) in the forward area, the knowledge thus gained could be filtered back through various channels to New Zealand, and be absorbed into the general culture. Washington maintained "the books" for all client states with which it was involved during WW2 under various individualised Lend-Lease schemes, with expectation that all clients would attempt to provide as much Reverse Land-Lease goods/services back to the USA, which could then either used by themselves, or transferred to other nations (which is why the official name of "Lend-Lease" was "Mutual Aid"). However if a client state had no way of avoiding cash purchase of goods, I guess they had to front up and do just that, although whether this actually happened, I do not know. However even fairly poor nations could usually find something that was always in demand, such as food, clothing or other textiles, minerals, coal, etc. As many forumites might know, NZ was able to settle all its Lend-Lease accounts by August 1946, whereas the cash-stripped United Kingdom had to keep on paying till the early years of the 21st Century.

In case anybody is interested in how we got British aircraft (before we were accepted into the American system), we had no problems in obtaining training aircraft (because we were prepared to accept obsolete RAF operational types just prewar and then early years up till about late 1940/early 1941 - Vincents, Hinds, Gordons - for very modest prices apparently!), and our initial order for five Oxfords in 1937 was massively reinforced by allocations under the Empire Air Training Scheme (EATS) which we had signed in December 1939 at Ottawa, which obligated us to supply trained (and semi-trained) aircrew for service with the RAF at any location in the World, with considerable numbers of semi-trained pilots being shipped to Canada from late 1940 onwards, to complete their advanced training with Canadian schools. We decided to order 14 Ansons in late 1941/early 1942, for our very own School of General Reconnaissance, and in 1943 we ordered nine more Ansons for communications duties (Oxfords were not as suitable as Ansons), but these on arrival were shanghaied by the School of GR as that school was now expected to train navigators for Pacific operations, so nine Dominies were ordered to replace them in this role. The Ansons and Dominies, as well as about ten Walrus were probably all paid for directly by NZ taxpayer, unlike most of the wartime Oxfords and Harvards, which were financed by the EATS, although each contributing member of this scheme had to pay monthly "contributions" (progress payments) in proportion to the efforts and outputs of each member, calculated to build up, then operate the entire scheme until it was no longer required. I believe that all contributing nations to the EATS (later known as the British Commonwealth Air Training Scheme, or BCATP) were able to keep up these payments such that the whole scheme was wound up satisfactorily in 1945, without any loose ends. We also had an arrangement with the Canadian Govt for supply of Canadian-manufactured aircraft, although this was complicated by fact that of the 59 Canadian aircraft we received, 56 were Catalina flying boast which were actually financed by the US government under LL; the other three were Harvards, of a type which it was intended to gradually replace American built variants had the war continued into 1946 (as expected). We also had to pay the British Govt for all of our Hudsons (and our early Kittyhawks), as these were all supplied directly from their factories as diversions from RAF orders (many pre-Lend-Lease). I have never found anything on how we arranged to pay for (or even why we asked for) the four Sunderland transport flying boast delivered to NZ in late 1944, although the Americans were deeply suspicious of these aircraft as they passed right through the USA en route to Auckland from the UK. Enough said about them, but I am certain New Zealand had to pay for these aircraft, one way or another. They were not a raging success in their role as transports.

As can be seen, for most of WW2 it was really extremely difficult to obtain war goods (including training and transport aircraft) during such events, practically impossible really, without having to undertake to place such aircraft (and personnel) under the control of foreign commanders in areas quite distant from New Zealand (combat aircraft), or to undertake to train large numbers of New Zealanders for service with the RAF, even though once under RAF control, the British Government undertook to pay them (although at RAF rates of pay; any shortfall in comparison to RNZAF pay was made up by transfer). The NZ Govt had practically no control over RNZAF personnel serving with the RAF, except under the most unusual circumstances, as they were under RAF administration for practically all purposes. Even the "Article XV" squadron members had no real privileges, despite their slightly higher status. Members of the 2nd NZEF (Army) were never put in this situation.

The Americans were pleased when any other friendly country offered to take on some of the risk of operating combat squadrons in forward areas, often alongside similar American units; governments who thought they could get modern aircraft, but "Keep them at home, just in case" would be quickly disabused of any such ideas. The only type of air force units they wanted under their commanders were the ones prepared to take a full part in the offensive, not the ones who wanted to stay at home. End of story.

[Mustang51]

Zac....that idiot who wrote the Mustang book all those years ago did not go into the purchases proposed as, from memory which is dimming, it was very difficult to obtain information on this from Oz in the late 60s and much of what was obtained appeared to be contradictory

[nuuumannn]

Interesting and detailed write-up, Dave. A couple of good books on the Lend-Lease orders and the British Air Commission as a matter of background.

www.aviation-bookshop.com/shop/the-british-air-commission-and-lend-lease/

www.amazon.com/Air-Arsenal-North-America-Lend-lease/dp/1857801636

[ZacYates]

Nov 2, 2021 18:29:30 GMT 12 joey05 said:

From the oh so reliable wiki

P-51M (NA-124)
The P-51M-1-NT was based on the P-51D-30-NA/NT, but utilized the V-1650-9A engine lacking water injection and therefore rated for lower maximum power than the -7. One was completed out of the original 1629 ordered, AAF Serial Number 45-11743.

Also from Wiki (my italics for emphasis):

The P-51H was designed to complement the P-47N as the primary aircraft for the invasion of Japan, with 2,000 ordered to be manufactured at Inglewood. Production was just gathering speed with 555 delivered when the war ended. Additional orders, already on the books, were canceled. With the cutback in production, the variants of the P-51H with different versions of the Merlin engine were produced in either limited numbers or terminated. These included the P-51L, similar to the P-51H but utilizing the 2,270 hp (1,690 kW) V-1650-11 engine, which was never built; and its Dallas-built version, the P-51M, or NA-124, which used the V-1650-9A engine lacking water injection and therefore rated for lower maximum power, of which one was built out of the original 1629 ordered, serial number 45-11743.

So I'm confused!

[davidd]

Am fairly certain the P-51M was merely a variant of the late D models, and had NOTHING TO DO with the lightweight models at all. How all this confusion has arisen all these years after WW2 is some sort of an indictment of somebody - or something! Would some other body (not me) with excellent references on the P-51 types please sort this lot out.
David D

[Mustang51]

David, You are correct

[ZacYates]

Thanks gents. There goes my idea of building a P-51H model in RNZAF colours!

[shorty]

Were not the Venturas to be replaced with B-25 Mitchells? This was because of our equipment supplier changing from the USN to the USAAC?

[Dave Homewood]

Lockheed Harpoons were actually on order to replace the Ventura fleet. Four of them arrived before the decision was made they were no longer needed. And after a bit of flying by guys at Whenuapai, the four returned to the USA.

[davidd]

To be strictly correct, the 47 PV-2s were ALLOCATED to the RNZAF for delivery from late 1944 onwards as ATTRITION aircraft to replace losses of the PV-1s, although in reality they would have been treated by RNZAF as "modified" PV-1s to keep our Bomber Reconnaissance force in being through till mid 1945 or later. The FG-1D Corsairs allocated to the RNZAF for earlier months of 1945 were likewise intended as attrition aircraft (to support the reducing 1944 allocation F4Us) until a newer type was selected for delivery from July 1945 onwards (the P-51s).

As PV-1 production ended on last day of May 1944, Lockheed had hoped to smoothly bring the largely similar PV-2 onto the line at Burbank (although first PV-2 had been delivered to US Navy as early as November 1943, with production deliveries commencing from last day of March 1944) and crank up production fairly quickly to re-quip existing Patrol squadrons. However, unexpected serious design defects in the wing structure brought the whole programme to a shuddering halt shortly thereafter, when many new PV-2s with US Navy squadrons began exhibiting severe wrinkling of the mainplane upper surfaces. Although some "fixes" were dreamed up for these aircraft, it rapidly became apparent that an entire redesign of the wings was called for, which took months to implement on the production line. In the meantime, all existing PV-2s (fortunately not too many) were either grounded, or restrictions were placed on weights and airspeeds or specific manoeuvres, which really made them useless for normal operations.
As noted by Dave H above, New Zealand's first four PV-2s did not arrive in Hawaii until February 1945, and were then ferried (after assembly) to New Zealand in March and April. However, the decision had already been made by the American theatre commander, in consultation with RNZAF, to cancel the entire PV-2 delivery programme because the war in what was known as the Norsols/Bismarck area was slowly winding down and there were already ample Marine Corps PBJ (Mitchel) squadrons already in the area, or due to arrive shortly, to handle the remaining Japanese forces trapped there. Despite a period of unusually heavy losses of PV-1s during period October 1944 to January 1945, the RNZAF managed to maintain its Bomber Reconnaissance force more or less intact without having to reduce its front line strength for a few months more, although this entailed putting half a dozen of the disgraced B-34s back into service at Whenuapai until June. A gradual reduction in the RNZAF's Ventura squadrons was commenced from March 1945, with Nausori (Fiji) being the first station to close (8 Squadron was effectively disbanded on its return to NZ at end of that month), and a second followed in June with close down of Guadalcanal as a Ventura base (and more or less simultaneous disbandment of 3 and 9 Squadrons). The remaining three squadrons (1, 2, 4) were then to continue rotations at the two primary operational bases, Los Negros or Jacquinot Bay, with periodic periods at Whenuapai, where at any given time half the crews would be on leave, other half to remain operational for local defence purposes. No. 1 Squadron was projected to disband on return from its last tour at Los Negros in January 1946, leaving the other two to continue operations as long as required by the American commanders. With the unexpected surrender of Japan in August 1945, No. 1 Squadron, then located at Whenuapai, was disbanded when orders to do so were issued on 15th of that month, with last two personnel (Adjutant and squadron clerk) being posted out on 10th September, all remaining squadron records being sent to Air Department in Wellington for storage. This left the two remaining squadrons (2 and 4) still on duty in the forward area when the war ended, carrying out security patrols, etc, which included low altitude surveillance of the by-now fully apparent Japanese armed forces strolling around on the beaches, burning all kinds of unknown material in full sight, fishing, helping move vast amounts of equipment into the open, and often waving cheerily as the Allied aircraft flew past. Soon they were heavily involved in escorting over 200 Corsairs home to New Zealand (F4Us and FGs), and thereafter only No. 2 Squadron remained located at Ohakea for another seven months or so before all remaining airworthy PV-1s were withdrawn from service.

David D

[Dave Homewood]

That is some really interesting detail there David. I have never looked into the history of the Harpoon and was unaware of the wing problems and the production issues.

I wonder if the RAF had been looking at re-equipping Coastal Command Hudson and Ventura squadrons with Harpoons till these problems arose?

[Dave Homewood]

Here is an email just in from Mark McGuire, with some info on the Mustang orders.

Hi Dave

I was in ArchivesNZ Wellington and looked at this file Archway :: Item Full Description (archives.govt.nz) which has some information relating to the thread discussing which model of Mustang was allocated to the RNZAF. Below is an extract from a letter, of July 1945, from the New Zealand Air Mission in Washington reporting on a visit to the factory manufacturing the aircraft for the RNZAF.

"Tentative blocks on which the factory are working are as follows:-

Block #15 July Quantity 30 P51D-25-NT aircraft

" #2 Aug " 25 P51-M-1 NT aircraft

" #5 Sept " 30 P51-M-1 NT aircraft

4. The main difference between the P51-D-25 and the P51-M-1 is in the engine installed; the P51-D-25 has the Packard Merlin V-1650-7 and the P51-M-1 will have the Packard Merlin V-1650-9A. The -9A has a slightly improved performance over the -7, and whereas the -7 was never intended for water injection, the -9A is designed to operate with water injection. However, water injection cannot be used on either the P51-D-25 airplane or the P51-M-1. For your information, the P51H airplane has the V1650-9 which is identical with the -9A except for minor details of plumbing as the P51H does actually make use of water injection."

Kind regards

Mark McGuire