For reference purposes I’ve collated a list of production batch numbers for the CAC Wirraway aircraft delivered to the RAAF between July 1939 and July 1946. This page contains the batch numbers for Mark III Wirraways, which were delivered under the CA-16 production “contract”. A summary of Mark III production is given in the table below:

DAP = Department of Aircraft Production

Batch numbers
Wirraway Mark III production was planned in batches of 11 aircraft. But there was one exception:

• The final batch of production, batch “N” consisted of only 3 aircraft to make up 135 aircraft

Batch numbers consisted of a letter for each batch followed by a number for each aircraft in that batch (e.g. A1, A2, A3, A4, etc)..The letters I, O, Q and V were generally not used as batch numbers, as they could be confused for numbers. The CA-16 contract started with batch “A”.

The definitive source for batch numbers is a ledger book kept by Mr Gordon Parker, Supervisor in the Sales Department, and one of CAC’s earliest employees from 1936. This book is now held in the collection of the Australian National Aviation Museum at Moorabbin Airport.

Unfortunately there are two discrepancies in the last 25 entries in the ledger. Firstly, Parker skipped batch “L” for A20-733 to A20-743 and went straight from “K” to “M”. We know that batch “L” was not skipped in reality, as two surviving data plates reclaimed from airframes at Tocumwal show L2 for A20-734 (c/n 1186) and M5 for A20-748 (c/n 1200). Secondly, Parker stopped recording batch numbers at A20-740, so the batch codes shown in the list below are “extrapolated”. The batch “M” extrapolation is supported by the evidence of the M5 batch number on the A20-748 data plate. This leaves a question as to the last three aircraft – were they N1, N2 and N3, or was batch M continued for three more aircraft, as M12, M13 and M14. I have postulated that a new batch “N” was commenced, since CAC did not expect to end production at 755 aircraft. There were many debates between CAC and DAP over how many aircraft to supply to the RAAF (the original order was for 150 aircraft, and another order had been received for 100 additional “Dive Bomber” aircraft planned as CA-20, but only 135 were delivered under the CA-16 order), so it is logical to presume that the last three aircraft were N1, N2 and N3.

During production, batch numbers were temporarily attached to the firewall and then the rudder (once the engine was mounted). These temporary numbers are sometimes visible in factory photos.

Constructor’s numbers
These were a sequence of numbers allocated to each aircraft in the sequence that they came off the line. Wirraways delivered under the CA-16 contract were given constructor’s numbers from 1075 to 1209.

RAAF stores number
All equipment in the RAAF was allocated a stores number for tracking and accounting purposes. Aircraft were tracked under the category “A” and each aircraft was given a specific number, Wirraway aircraft being allocated the category A20. These numbers are often referred to as the “serial number” of the aircraft in RAAF service.

Linking batch numbers, stores numbers and constructor’s numbers
Here are several photos showing Mark III Wirraways under construction, allowing us to link the batch codes to RAAF stores/serial numbers.

Below we can see a group of camouflaged Mark III Wirraways on the production line. Batch numbers visible include D10 (furthest away, on the left) and E1 to E5 (closest, on the right). In the original photograph, D11 is also visible, sitting between D10 and E1, but pointing tail-on to the camera, so its rudder cannot be seen. These aircraft are A20-665 to A20-671, as evidenced by the three-digit number after the two-digit batch codes. 

Later in the CA-16 contract, below is a view of H8 (A20-707, c/n 1159) attached to the lifting sling. The batch label taped to the rudder showing H8-707 is repeated in the inset at lower right.

The photo below shows late CA-16 production, with the aircraft now painted overall Trainer Yellow.  K7 (A20-728) is visible sitting on dolly wheels, and the rudder of K8 (A20-729) is visible behind the aircraft (shown enlarged in the inset at lower left).

The table below lists batch numbers and construction numbers for all Mark III Wirraway aircraft, delivered under the CA-16 contract. The batch numbers are transcribed from Gordon Parker’s delivery records (with the last 25 entries corrected), and have been cross-checked with photographic evidence (some of which is shown above) and several frames and ID tags held in museums or private collections.

I welcome feedback on the table above, with supporting evidence of any possible inaccuracies.

References:

Commonwealth Aircraft Corporation. Sales Department Aircraft Delivery Ledger; Kept by Gordon Parker. CAC Collection, Australian National Aviation Museum.

Commonwealth Aircraft Corporation. Aircraft Drawing Office Manual. Incorporating up to Amendment List No. 2, Melbourne, Australia, 1946.

For reference purposes I’ve collated a list of production batch numbers for the CAC Wirraway aircraft delivered to the RAAF between July 1939 and July 1946. This page contains the batch numbers for Mark II Wirraways, which were delivered under the CA-3, CA-5, CA-7, CA-8 and CA-9 production “contract” numbers. A summary of Mark II production is given in the table below:

DCB = Defence Contracts Board
APC = Aircraft Production Commission

Batch numbers
Wirraway production was generally planned in batches of 10 aircraft. But there were two exceptions:

• At the end of the CA-5 contract, batch “Q” consisted of 12 aircraft, to make up the total of 32 aircraft delivered against this contract
• At the end of the CA-9 contract, batch “W” consisted of only 8 aircraft, to make up the total of 188 aircraft delivered against this contract

Batch numbers consisted of a letter for each batch followed by a number for each aircraft in that batch (e.g. A1, A2, A3, A4, etc)..The letters I, O, Q and V were generally not used as batch numbers, as they could be confused for numbers.

Usually a new contract (such as CA-1, CA-2, etc) started with batch “A”. However the CA-5 contract started with batch “N” (following from the final CA-3 batch which was “M”)

The definitive source for batch numbers is a ledger book kept by Mr Gordon Parker, Supervisor in the Sales Department, and one of CAC’s earliest employees from 1936. This book is now held in the collection of the Australian National Aviation Museum at Moorabbin Airport. The list below is transcribed from the Parker list, and has been checked against photographic records as well as airframes and ID tags held in museums and private collections.

During production, batch numbers were temporarily attached to the firewall and then the rudder (once the engine was mounted). These temporary numbers are sometimes visible in factory photos.

Constructor’s numbers
These were a sequence of numbers allocated to each aircraft in the sequence that they came off the line. For example, Wirraways delivered under the CA-3 contract were given constructor’s numbers from 41 to 100.

RAAF stores number
All equipment in the RAAF was allocated a stores number for tracking and accounting purposes. Aircraft were tracked under the category “A” and each aircraft was given a specific number, Wirraway aircraft being allocated the category A20. These numbers are often referred to as the “serial number” of the aircraft in RAAF service.

Linking batch numbers, stores numbers and constructor’s numbers
Here are several photos showing Mark II Wirraways under construction, allowing us to link the batch codes to RAAF stores/serial numbers.

Mark II Wirraways commenced with the 41st aircraft, A20-44 (c/n 41) and in the photo below we see the last Mark I aircraft (A20-42, on the far side of the factory closest to the doors) and the first Mark II aircraft (furthest to the right, with G1 batch number on the rudder). Workers are pushing G4 in the foreground (A20-46).

Early in CA-5 production the photo below shows six fins and rudders, from the left N8, with A20-110 also labelled, then N9 (batch label hidden) with its tail wheel on the ground, then N10 (batch label hidden), then P1 and P2 and finally P3 with its label hanging half-off. 

The photo below shows a group of Wirraway aircraft under construction, late in the CA-9 contract, around March 1942. Batch numbers taped to the rudder of each aircraft are (from the left) P6-570, P5-569, P1-565, N9-563. These correspond to A20-570, A20-569, A20-565 and A20-563. Incidentally, these aircraft (the last 56 in the CA-9 contract) were originally intended for the RAF, but the War Cabinet decided to retain them in Australia. They were also delivered with two-bladed propellers, as De Havilland had run out of imported “spider” castings for three-bladed propellers.

The table below lists batch numbers and construction numbers for all Mark II Wirraway aircraft, delivered under the CA-3, CA-5, CA-7, CA-8 and CA-9 contracts. The batch numbers are transcribed from Gordon Parker’s delivery records, and have been cross-checked with photographic evidence where possible (some of which is shown above) and several frames and ID tags held in museums or private collections.

Note that it is possible that not all batch numbers correspond exactly according to Gordon Parker’s list as transcribed below. There may have been periods where a welded frame with a given batch number was taken from stock and assembled into an airframe with a different constructor’s number. For example, the first aircraft supplied under the CA-5 contract, the famous A20-103 (C/N 103) in the War Memorial, should have the batch number N1 according to Parker’s list (as shown below), however a collector has a bracelet with the N1 batch number in a private collection. So the frame in A20-103 may not have been the frame labelled N1 as would be expected.

I welcome feedback on the table above, with supporting evidence of any possible inaccuracies.

References:

Commonwealth Aircraft Corporation. Sales Department Aircraft Delivery Ledger; Kept by Gordon Parker. CAC Collection, Australian National Aviation Museum.

Commonwealth Aircraft Corporation. Aircraft Drawing Office Manual. Incorporating up to Amendment List No. 2, Melbourne, Australia, 1946.

For reference purposes I’ve collated a list of production batch numbers for the CAC Wirraway aircraft delivered to the RAAF between July 1939 and July 1946. This page contains the batch numbers for Mark I Wirraways, which were delivered under the CA-1 production “contract” number. This contract number was an internal number used by CAC (similar to the accounting “charge number” system used by North American Aviation) and was not the actual contract number from the Defence Contracts Board.

DCB = Defence Contracts Board

Batch numbers
During construction, each aircraft was given a batch number, for the ordering of parts and materials. Batch numbers consisted of a letter for each batch followed by a number for each aircraft in that batch (e.g. A1, A2, A3, A4, etc). Wirraway production was generally planned in batches of 10 aircraft. But there were exceptions, as it appears the first 10 aircraft were produced in two batches of five (more on that below).

The letters I, O, Q and V were generally not used as batch numbers, as they could be confused for numbers. Usually a new contract (such as CA-1, CA-2, etc) started with batch “A”.

The definitive source for batch numbers is a ledger book kept by Mr Gordon Parker, Supervisor in the Sales Department, and one of CAC’s earliest employees from 1936. This book is now held in the collection of the Australian National Aviation Museum at Moorabbin Airport.

During production, batch numbers were temporarily attached to the firewall and then the rudder (once the engine was mounted). These temporary numbers are sometimes visible in factory photos.

Constructor’s numbers
These were a sequence of numbers allocated to each aircraft in the sequence that they came off the line. For example, Wirraways delivered under the CA-1 contract were given constructor’s numbers from 1 to 40.

RAAF stores number
All equipment in the RAAF was allocated a stores number for tracking and accounting purposes. Aircraft were tracked under the category “A” and each aircraft was given a specific number, Wirraway aircraft being allocated the category A20. These numbers are often referred to as the “serial number” of the aircraft in RAAF service.

Linking batch numbers, stores numbers and constructor’s numbers
Here are several photos showing Mark I Wirraways under construction, allowing us to link the batch codes to RAAF stores/serial numbers.

The photo below (Figure 1) shows a group of fuselages under construction at the CAC factory. This is very early in the production (note the two Gannet aircraft near the hangar doors), and the batch number C2 can be seen attached to the firewall. Unfortunately no serial codes are evident, and so we can’t definitively connect this batch number to a serial number. But by tracing back from other aircraft in batch C (explained below), C2 would have been A20-9.

Another photograph of early Wirraway production (Figure 2, below) shows A20-21 on the production line, with the batch number D9 on plaques attached to the firewall and also the rudder. The camouflaged Wirraway behind A20-21 has the batch number E1 on its firewall, corresponding to A20-23 which was the first aircraft delivered to the RAAF in camouflage.

Taken immediately beside the photo above, Figure 3 below shows A20-20 on the production line, with its engine installed. The batch number on the rudder is not readable, due to the angle of the rudder. Immediately behind sits another silver-doped Wirraway with batch code D10 on the firewall (corresponding to A20-22, although the serial number is not visible in the photo), the last silver-doped Wirraway.

Unfortunately Gordon Parker only started recording the batch numbers from H8 onwards (A20-60, well into the CA-3 contract). So we need to “reconstruct” the earlier batch numbers based on other evidence including:

• Photograph evidence, including the photo above (Figure 1) showing that D9 was A20-21 (c/n 19)
• The  Clyde Engineering tag on A20-10 at the Australian National Aviation Museum reads “SERIAL 01/3124/C3”, linking batch number C3 to A20-10 (c/n 8)
• A frame in a private collection which is identifiable as a CA-1 forward frame has  the original CAC identification tag which reads “Serial 01-3124-C2“, meaning that C2 was a CA-1 contract aircraft, most likely A20-9 (c/n 7) – see Figure 1 above
• Information from a file in the National Archives of Australia (NAA: A705, 9/15/193, “Wirraway aircraft – Contract and Specification”) on 3/1/1939 describing some missing “joint wrap plates” on the first 9 aircraft confirms their batch identifications as A1, B1, B2, B3, B4, C1, C2, C3, and C4.

Counting back from D9 (A20-21, c/n 19) we can postulate that D1 was A20-13 (c/n 11). If we then assume that batch C was 5 aircraft, then C5 would be A20-12 (c/n 10) and C1 would be A20-8 (c/n 6). This fits with A20-10 (c/n 8) being C3. 

Thus we can arrive at the table below showing the batch numbers for all Mark I Wirraway aircraft delivered under the CA-1 contract.

Caveat lector: These batch numbers were current at the time the aircraft left the factory. During RAAF service, various parts could be changed during repairs, resulting in possible differences between batch numbers and serial numbers as listed below. So one should not expect that this list will perfectly match with frames in existence today, and if trying to identify a particular frame from its batch number tag, additional evidence should be sought.

I welcome feedback on the table above, with supporting evidence of any possible inaccuracies.

Updated 4/8/2021 with information about the first 5 batch numbers A1 to B4.

References:

Commonwealth Aircraft Corporation. Sales Department Aircraft Delivery Ledger; Kept by Gordon Parker. CAC Collection, Australian National Aviation Museum.

Commonwealth Aircraft Corporation. Aircraft Drawing Office Manual. Incorporating up to Amendment List No. 2, Melbourne, Australia, 1946

National Archives of Australia, NAA: A705, 9/15/193, “Wirraway aircraft – Contract and Specification”