Merlin XX propeller reduction gear 0.42 to 1, British (SBAC) propeller shaft
Merlin 28 propeller reduction gear 0.42 to 1, British (SBAC) propeller shaft
Merlin 29 propeller reduction gear 0.477 to 1, US (Spline) propeller shaft
V-1650-1 propeller reduction gear 0.477 to 1, US (Spline) propeller shaft
Packard produced two batches each of 240 Merlin 29, first February/March 1942 plus 1 in April, second July to December 1942. The 480 Hamilton 23E50 propellers for the engines were produced March to August 1942. Canada then used them to build 400 Hurricane IIB(Can)/mark XII June 1942 to May 1943, alongside the final 101 RAF order aircraft February/March 1943. As noted 150 of the Canadian order were sent to Britain.
Again as noted the British record the arrival of 234 Hurricane II fitted with Merlin 28, called mark III while the engine was retained, prototype was DG633 with Canadian-built aircraft JS220, JS244 and JS322 reported as further Mk.III trials aircraft.
All 4 of the above engines could be fitted to a Hurricane, P-40F or L.
Please understand Canada exported incomplete Hurricane airframes, one reason they were so suitable for conversion to Sea Hurricanes. Few Canadian built Hurricanes were test flown immediately after assembly and in fact most as rolled out of the factory were not ready to fly even if an engine was available. A report in December 1941 noted stored mark I airframes were complete less wheels, brakes, tyres and tubes but needing engines, propellers, instruments, and all other appendix A Serial 1160 Embodiment Loan Equipment. The mark II then in production emerged from the factory in a similar state to those stored, "require from England, wheels, brakes, air compressors and drives and couplers for same, hydraulic pump drives and couplings, airscrews and instruments". The brakes being magnesium alloy castings. The ex RCAF order aircraft were stripped down to this sort of standard before export. This freed Merlin 29 to upgrade the survivors of 30 Hurricane I fitted with Merlin III and propellers from Fairey Battle as an emergency measure in early 1942 plus the survivors of 50 Sea Hurricane I meant as the North American pool for the Merchant Ship Fighter Unit but absorbed into the RCAF.
The rebuild of Packard Merlins imported to the UK was very common as Packard built huge whole batches of engines without modifications so that they could produce the volume. Where UK rebuild to incorporate updates was found to be worthwhile, those engines were rebuilt.
Interesting.
So, it is not that strange that the Hurricane engines were removed for Lancasters and the Hurricanes got the Merlin XX fitted.
The removal of the Merlin 28 from imported Hurricanes had nothing to do with engine modifications, it meant all Hurricane II had the Merlin XX engine as a world wide standard, rather than complicating the supply situation with a relatively small number of "non standard" engines which gave the aircraft the same performance anyway.
The British concentrated their US Merlins in Lancasters, none fitted to Halifax or British built Mosquito for example, this simplified maintenance requirements. Canada and Australia used US Merlins for their relevant production. When the Merlin 266 arrived for Spitfires the mark XVI was kept in Britain or North West Europe, mark IX exported to overseas commands and the USSR.
There may have been some Canadian built Hurricanes built with the Merlin 28 and/or 29, but as far as I know, the Merlin 28 were only used operationally by the Canadian built Lancasters and occasionally some British built Lancasters that were refitted with the Merlin 28.
After losses at sea the British record the arrival of 4,937 Merlin 28 from May 1942 to July 1943. Lancaster III production began in December 1942, with 738 built by end July 1943, with another 640 Merlin 28 engine and 721 Merlin 28 power plants in stock. Merlin 38, which was the next Packard Merlin for Lancaster, began production in March 1943.
Canadian Lancaster production began in August 1943, the first 75 used Merlin 38 according to Harry Holmes, then Merlin 224.
Agreed no Hurricane III saw combat.
This may be true and it might not be true. What was planned short term and what was planned long term may be different things.
Yes.
They built about 5220 (?) P-40Ns from March 1943 until Nov 1944 under a number of contracts and dash numbers.
Minor point, all P-40N were ordered under contract AC-34423, the first 2,000 on 25 January 1943 under the H program "Acceleration" which had been approved April 1942, with a further 2,000 approved under the I program (Fiscal year 1943), this included the XP-40Q, then 1,000 under the J program (Fiscal year 1944) under Supplement 4 to the contract, dated 14 February 1944, then another 1,000 under Supplement 22 dated 30 June 1944, this final 1,000 was cut to 700 in August and 220 in September 1944. Result 5,219 P-40N, 1 XP-40Q., consisting of 400 N-1, 1,100 N-5, 100 N-10, 377 N-15, 1,523 N-20, 499 N-25, 500 N-30, 500 N-35, 220 N-40
The first 400 built were called "base fighters" officially, they may have had other un-official names. With only 4 guns, limited ammo, one fuel tank taken out, aluminum radiators and oil coolers and other weight saving measures (taking out the electric starter and using a small battery may not have been a good idea) that saved 464lbs off the empty weight. Normal gross was about 580lbs less than a P-40M.
Seems to be a last ditch attempt at having speed and climb performance. "Similar to the P-40, E, K and M types of airplanes except as follows; Different engine with boost control; armament 4 0.50 cal. wing guns; no provisions for wing bombs, increased armour plate protection; no front wing tank; mechanical landing gear, flaps and indicators; non metallic tanks; SCR-522 radio; alternate SCR-274N; Type A-12 demand oxygen system. [Acceptance March 1943, stripped light weight P-40 similar to P-40H except change in armament, removal of battery, starter and auxiliary wing fuel tanks saving 484 pounds. Items reinstalled in service and N-5's were fully equipped]"
The -5 (1100 built) model got the 6 guns armament back, restored the normal fuel tankage and put back some of the normal operational equipment (electric starter and big battery).
"redesignated with the following: landing gear book; revised pilot's seat; provisions for complete SCR-695 radio equipment; recognition lights; revised fuselage rear vision; provisions for wing bombs and wing fuel tanks; draft curtain; substitution of 27 inch magnesium wheels. [Armament increase, addition of auxiliary wing fuel tanks, wing racks to accommodate larger fuel tanks or bombs. Provision for trans Atlantic towing by B-17]"
The 27 inch wheels did not really work out well with the heavier loads, it took to the N-40 to restore the 30 inch wheels.
With Curtiss cranking out over 300 airplanes per month P-40N-1 production did not last long. ... The March/April built P-40N-1s didn't see combat until June 1943 in the Med and July with the 5th Air Force in the SW Pacific and Sept with the 80th FG over Burma.
I am struggling to find USAAF use of the P-40N in the Mediterranean, the 12th Air Force reporting as late as April 1944 not even for training. The three RAF squadrons operating Kittyhawk IV, 112, 250 and 450 report equipping in April 1944, January 1944 and October 1943, 5 SAAF in October 1943, 11 SAAF in November 1944, 3 RAAF April 1944. The British reporting the first Kittyhawk IV imports around July 1943, end month the RAF census reporting 14 in the Middle east, 81 en route, while 5 had already been lost overseas and 3 en route.
Australia reports the first deliveries to the RAAF in mid July 1943, New Zealand to the RNZAF in June. RAAF A29-434 = USAAF 42-104969 Sent as part of a 25 aircraft shipment to 5th AAF USAAF. Not a RAAF Contracted P-40N-5 but possible replacement for single P-40N-1, 42-104659 ex Mac Air A29-1001 that was issued to 49thFG as first of P-40N type received for evaluation 15 July 1943.
There were 400 N-1, production finishing in mid May 1943, to end May 1943 a total of 618 P-40N had been accepted.
P-40N the 3 months March to May 1943, total acceptances 54, 184, 380, total deliveries, 54, 177, 364, total exports, 44, 95, 239, Acceptances by user:
USAAF 10, 81, 91
Australia 0, 9, 80 (exported same month as accepted)
Britain, 0, 0, 106 (102 exported in May)
Britain for USSR 44, 86, 0 (exported same month as accepted)
Canada, 0, 7, 3 (6 exported in May)
China 0, 0, 30 (exports from June)
NEI 0, 0, 1 (exported same month as accepted)
New Zealand 0, 0, 50 (exported same month as accepted)
I believe exported is the USAAF handed control over to the relevant authority, not departed US.
