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Ceres book now available

The new book describing the CAC Ceres agricultural aircraft is now available!

The Ceres agricultural aircraft was the first – and only – civil aircraft produced by Commonwealth Aircraft Corporation (CAC) in Australia – a company which had previously produced hundreds of military aircraft including fighters such as the Boomerang, Mustang and Sabre, and trainers such as the Wirraway and Winjeel. Between 1959 and 1963 a total of only 21 Ceres aircraft were produced, but as a one-ton-load heavyweight crop duster the Ceres made its mark on aerial agriculture in Australia and New Zealand.

The result of more than 15 years of research by the author, this book tells for the first time how the CAC design team overcame unexpected problems during the development of their first civil aircraft. Developed from the pre-war Wirraway general purpose and training aircraft, the adaptation of the Wirraway engine and airframe to the dramatically different flight regime of crop dusting was not without problems. The book covers the fascinating history of the production and operation of the Ceres aircraft. To provide context for the design of the Ceres, the book covers the development of agricultural aviation in Australia and New Zealand, with a brief summary of the aircraft which were in use prior to the introduction of the Ceres. The individual history of each Ceres aircraft produced is covered, along with impressions of the aircraft from the perspective of numerous pilots and operators.

A little-known aspect of the Ceres story is how the unused stock of surplus Wirraway airframes purchased by CAC for Ceres production were eventually sold – ensuring the survival of dozens of Wirraway aircraft in the hands of private enthusiasts and museums. This was how the Ceres saved the Wirraway!

A full technical description of the aircraft is included, along with excerpts from the Operating Instructions and the Maintenance, Repair and Overhaul Manual. Many unpublished photographs and drawings are included. The three major versions of the aircraft are described in detail.

The book includes 8 full-colour profiles by renowned aviation artist Juanita Franzi, of Aero Illustrations.

256 pages, printed in high quality colour on matt paper.

597 photographs in colour and black & white.

ISBN 9780994571304

Table of contents:

Introduction      i
Chapter One    Background: Agricultural Aircraft in Australia and New Zealand    1
Chapter Two    Design, Testing and Development of the Ceres    23
Chapter Three    Production and Sales    71
Chapter Four    Operators: The Companies Who Flew the Ceres    87
Chapter Five    The Ceres Described    97
Chapter Six    Flying the Ceres    121
Chapter Seven    Individual Aircraft Histories    129
Appendix 1    Lineage: Ancestors of the Ceres    220
Appendix 2    Service Life and Operators     223
Appendix 3    Surplus Wirraways Purchased by CAC    225
Appendix 4    The Company Wirraway: CA9-763    227
Appendix 5    Ceres Service Bulletins and Modifications    229
Bibliography    234
Index    236

You can order the book from the author by clicking on “Store” above and selecting which version you would like to purchase.

You can also order the book from several online bookstores, including:

Wheelers books (search for ISBN 9780994571304)

Which design for the Wirraway?

Before deciding which design to build locally as the Wirraway, CAC were asked by the Air Board to import two different prototypes from North American Aviation (NAA) for evaluation in a “fly-off”.

Here’s a quick summary:

The first aircraft imported was the NA-16-1A (also known by its NAA accounting code, NA-32), a fixed-gear trainer with a direct-drive Pratt & Whitney Wasp R-1340 driving a two-bladed propeller. The newspapers of the day commonly referred to it as the “NA-16” (however this was a little misleading, since the NA-16 was actually a different aircraft, but they didn’t really understand that, and the name stuck in popular usage).

The second aircraft imported was the NA-16-2K (NAA accounting code NA-33), a retractable-gear trainer with a geared Pratt & Whitney Wasp R-1340 driving a 3-bladed prop. It was commonly known as the “NA-33”.

The drawing below shows these two aircraft compared with the Mk I Wirraway.

The RAAF held a “fly-off” between the two aircraft and decided that the NA-16-2K was a more capable aircraft.

Therefore the Wirraway was based on the NA-16-2K, but with numerous modifications added to meet RAAF requirements.

The NA-16 (actually the NA-16-1A)

During the process of selecting a design to be constructed as the Wirraway, the Air Board requested CAC to purchase one example of their chosen design so that it could be tested by the RAAF. Thus CAC ordered the sole NA-16-1A in early 1937. The NA-16-1A (also known by its NAA accounting code or “charge code” of NA-32) was a single-engined 2-seat training and general purpose aircraft.

In the newspapers of the day, this aircraft became widely known as the “NA-16”, even though this was not technically correct. In this short article, I will refer to the aircraft by its NAA model number, NA-16-1A.

The NA-16-1A was constructed at the Inglewood, California factory of NAA and flight tested before being dismantled and crated prior to shipping to Australia. Contemporary manuals published by NAA describe the NA-16-1A as “Modified BT-9D, Australia”. The main modification was the installation of a Pratt & Whitney Aircraft R-1340 Wasp engine, as opposed to the Wright R-975 Whirlwind in the BT-9D.

Above: This photograph shows the sole NA-16-1A in California prior to its delivery to Australia (San Diego Air and Space Museum).
Above: A head-on photograph of the NA-16-1A in California prior to its delivery (San Diego Air and Space Museum).
Above: Another photograph of the NA-16-1A in California prior to its delivery.
Notice that the aerial mast appears to have been removed when this photo was taken (San Diego Air and Space Museum).
Above: Another photograph of the NA-16-1A in California prior to its delivery. The corrugated skin on the horizontal stabilizer (as well as the tail fin) is evident in this image (San Diego Air and Space Museum).

The NA-16-1A arrived in Australia on August 9th 1937[1] and was assembled at Point Cook, since the CAC factory was still under construction.

There was a good deal of discussion about who should carry out the first flight of the aircraft in Australia once it had been assembled, since CAC had not yet engaged their own test pilot at this point. Options canvassed included:

  • Major Victor Bertrandias of Douglas Aircraft (who was due in Melbourne in October, but was obviously going to be too late)
  • Moye Stephens, the pioneering aviator and co-founder of Northrop, who was in Australia at the time on behalf of Lockheed
  • Eric Chaseling (who was in California at the time, taking delivery of VH-ABH from Lockheed for Associated Airlines, and could be checked out by NAA before leaving for Australia, where he was due on 16 September)
  • Sqn Ldr Frederick Scherger, Director of Training for the RAAF who was a highly experienced pilot with experience on similar types

Wackett was in California at the time, but a conference between the Air Board and CAC was held in Melbourne on 23 July to discuss the question. Chief of Air Staff Richard Williams believed that RAAF pilots could handle it, but he would welcome an American expert if CAC were covering the cost. Wackett cabled on 9 August, noting Moye Stephens was in Australia, but not recommended by Kindelberger of NAA, and that he (Wackett) suggested Chaseling instead.

Several days later it was agreed that the RAAF would provide the pilot, and so on 26 August CAC was advised that Sqn Ldr Frederick Scherger would be made available.

The aircraft made its first flight on September 3rd[2] in the hands of Sqn Ldr Scherger, lasting for 55 minutes, with two loops included. The acceptance testing and handling trials program required by the RAAF was completed in six days, with a total of 6 hours 40 minutes of flying time.

Above: This photograph shows the NA-16-1A at Point Cook shortly after its arrival in Australia in 1937. It is seen in the company of de Havilland Moth primary trainers. It bears RAAF roundels, but no serial number so presumably this photograph was taken before the NA-16-1A was handed over to the RAAF on February 2nd 1938 (Australian War Memorial ref P02515.002).
Above: Cadet Geoff Nicholl (later Wing Commander) from the RAAF College, standing beside the NA-16-1A at Point Cook in 1937 (Australian War Memorial ref P02515.001).

In December 1937 a series of comparative flight tests were carried out between the NA-16-1A and the NA-16-2K (a retractable-gear version).

On 13 January 1938 Ellis Wackett wrote to Williams (CAS) to reply to his enquiry about critical comments on the NA-16 which appeared in C.G. Grey’s editorial in The Aeroplane on December 8th 1937. Without naming his sources, Grey commented:

The first NA 16 to be seen in Australia was inspected at Sydney a few weeks ago… The first is still expected to fly in February. The machine did not excite much comment, and pilots who have handled it are not impressed by its performance in bad weather, when it is apt to do many things which it should not. 

Ellis Wackett mentioned to Williams that he had discussed the issue with Sqn/Ldr Scherger and F/Lt Kyle (who had flown the aircraft to Sydney and back) and they “had nothing adverse to say about it and liked flying it”.

On January 14th 1938 the Air Board wrote to the Defence Department to inform the Minister that trials of the NA-16-1A and the NA-16-2K had confirmed that the NA-16-2K had superior performance and more desirable features.[3]

Since the NA-16-1A was no longer needed by CAC for development activities, it could now be handed over to the RAAF for conversion training for the new Wirraway aircraft which would later be entering service. This took place on February 2nd 1938, and from this point its history can be traced from RAAF records. Text in italics below is taken from the service card for A20-1[4]:

02/02/1938 Received at 1 Aircraft Depot (Laverton) ex CAC. Wasp engine number 6155. Order number A.30964

07/02/1938 Issued to No. 2 Squadron, Laverton

As soon as the aircraft was delivered to the RAAF, Group Captain Wrigley, Commanding Officer of RAAF Laverton, wrote to the Air Board pointing out that there was no cock (shut-off valve) installed between the oil tank and the oil pump[5], which could result in oil draining into the head of the lowest cylinders and possibly causing damage due to the high compression in this situation. The Directorate of Technical Services at the Air Board pointed out that later Wasp engines incorporated a non-return valve which served the function of the proposed cock without adding the risk that the engine could be operated with the oil turned off at the cock[6].

During its time at No. 2 (General Purpose) Squadron at Laverton, it was noticed that a large amount of flame was emitted from the exhaust manifold when the aircraft was performing aerobatics, particularly in slow rolling vertical climbs. In some cases flames could be seen extending along the full length of the fuselage by observers on the ground when the aircraft was flown inverted.

On April 27th 1938 the CO of No. 2 Squadron wrote to the CO of RAAF Laverton to express his concerns[7] as it was observed that heat from the exhaust had blistered the dope on the cowlings and wing covering at the root of the wing and had scorched the fabric on the removable fuselage side panel. The heat had even buckled some of the wing leading-edge skin near the root. The Squadron dismantled and checked the carburetor to determine if this was the cause and it appeared that a non-return valve (intended for inverted flight) was not installed on the carburetor and this was allowing excess petrol to flow into the engine. This excess fuel was not burned during the combustion cycle and ignited in the exhaust manifold, resulting in the flames coming from the exhaust pipe.

On April 2nd the aircraft was inspected at CAC by Lawrence Wackett and Pieter Schipper (Engineering Superintendent, who had joined CAC from Pratt & Whitney Aircraft in the USA). They pronounced the damage as only cosmetic and the aircraft as airworthy. They suggested repairing the aluminium skin when the aircraft was available to do so, and extending the exhaust manifold by 12 inches to prevent the hot exhaust flowing over the wing root when the aircraft was flown inverted. Photographs of the aircraft do not show any such extension so it appears this suggestion was not followed. However photographs of the aircraft later in its life show a metal patch on the lower front of the fuselage, replacing a section of fabric covering which would have suffered scorching again.

On June 1st 1938 the Directorate of Technical Services sent 8 rollers for installation on the sliding canopy sections to RAAF Laverton[8] and on June 22nd the Commanding Officer at Laverton informed the Air Board that these had been installed on the aircraft[9].

Above: This photograph shows the aircraft at Point Cook, following it’s transfer to the RAAF as A20-1 on 2 February 1938.The fixed landing gear, direct drive two-bladed propeller and flat-panel windscreen are noticeable.
The prominent scorch-mark from the exhaust pipe (caused by the lack of a non-return valve in the carburetor allowing too much fuel into the engine during vertical climbs or inverted flight) is also obvious along the lower side of the fuselage.
Image copyright expired, courtesy of the AWM archive.

24/06/1938 Received at No. 1 Flying Training School (Point Cook) ex 2 Squadron

During its time with No. 1 Flying Training School at Point Cook, the under-side of the tail-plane was damaged[10] and the aircraft was sent back to CAC for repairs. It was also noticed that the heads were breaking off some of the counter-sunk bolts along the front of the engine cowling[11].

24/08/1938 Returned to CAC for repairs.

Part of the skin was replaced underneath the tail-plane and some local reinforcing was also added.[12]

09/09/1938 Arrived 1 FTS ex CAC

23/09/1938 Wingtip struck ground at Point Cook

On October 5th 1938 an urgent request was placed with CAC to repair the starboard aileron and wing-tip[13].

On October 24th 1938 it was proposed that the aircraft should be withdrawn to No. 1 Aircraft Depot and held there until the first squadron to be equipped with Wirraways was ready[14].

On February 2nd 1939 the spark plugs were checked by CAC and found to be in excellent condition after 20 hours running time on the engine[15].

During the middle of April it was noticed that the Exide battery was inefficient, resulting in a ban on aerobatics issued on April 20th[16].

22/08/1939 Received No. 1 Squadron ex 1FTS

28/08/1939 Allotted No. 21 Squadron ex 1Sqn

17/10/1939 120-hourly service 23/10 Engine #6155

10/01/1940 Allotted No. 8 Squadron ex 21 Sqn

17/05/1940 Allotted 1AD ex 8 Sqn for complete overhaul

24/05/1940 Received 1AD ex 8Sqn for for ARS rep

12/06/1940 Allotted Engineering School ex 1AD

23/06/1940 Issued to Engineering School ex 1AD converted to Wirraway instructional airframe #2

Above: The NA-16-1A spent the later part of it’s life as an instructional airframe at No. 1 Engineering School, Ascot Vale (the Melbourne Showgrounds). Here two W.A.A.A.F. servicewomen demonstrate hand starting techniques. Note that the aircraft was painted in the standard war-time camouflage scheme by this point of its career.
Image copyright expired, courtesy of the Argus Newspaper Collection of Photographs, State Library of Victoria.
Above: Here is A20-1 again during the hand starting demonstration “photo shoot”.
Image copyright expired, courtesy of the AWM archive.
Above: Another view of the NA-16-1A while being used as an instructional airframe. From this view it appears to have been fitted with a standard Wirraway wing centre-section with retractable undercarriage, along with a standard hydraulic system and control shelf, not fitted during its flying life. The instructor is showing the keen students how the undercarriage retraction system functions.
State Library of Victoria, ref H99 206-2172

17/10/1945 Converted to components


A selection of books containing information related to the NA-16-1A:

  • Hagedorn, Dan. North American NA-16 / AT-6 / SNJ. North Branch, MN: Specialty Press, 1997. ISBN 0-933424-84-1
  • Smith, Peter Charles. North American T-6 SNJ, Harvard & Wirraway – A Pictorial Record. Ramsbury, Marlborough, Wiltshire, UK: The Crowood Press, 2000. ISBN 1-86126-382-1
  • Wackett, Lawrence Aircraft Pioneer – An Autobiography.Sydney, Angus and Robertson, 1972. ISBN 0207123780

Additional internet information sources

You can find more information regarding the NA-16-1A on these websites:


1. “FIGHTING AEROPLANES.” The Mercury (Hobart, Tas. : 1860 – 1954) 10 Aug 1937: 8. Web. 27 Jul 2012

2. “NEW FIGHTING ‘PLANE TESTED AT LAVERTON” The Sydney Morning Herald (NSW : 1842 – 1954), Saturday 4 September 1937, page 18

3. Letter 14/01/1938 from Secretary, Air Board to Secretary, Department of Defence, RAAF ref 16/1/7. National Archives of Australia, Series number , Control Symbol 

4. Aircraft status cards, Wirraway A20-1 to A20-305. National Archives of Australia, Series number A10297, Control symbol BLOCK 107

5. Letter 7/02/1938 from RAAF Laverton to Air Board, RAAF reference 212/1/2E. National Archives of Australia, Series number A705, Control symbol 9/15/5

6. Letter 28/02/1938 from DTS, Air Member for Supply to RAAF Laverton. National Archives of Australia, Series number A705, Control symbol 9/15/5

7. Letter 27/4/1938 from CO No.2 Sqn to CO RAAF Laverton ref 212/1/2. National Archives of Australia, Series number A705, Control symbol 9/15/5

8. Letter 1/6/38 from DTS to RAAF Laverton. National Archives of Australia, Series number A705, Control symbol 9/15/5

9. Letter 22/6/38 from RAAF Laverton to Air Board. National Archives of Australia, Series number A705, Control symbol 9/15/5

10. Correspondence file 10/08/1938 reference 1FTS 2729 (FS 115). National Archives of Australia, Series number A2408, Control symbol 9/15 PART 1

11. Correspondence file 10/02/1939 reference 1FTS 2728 (FS 114). National Archives of Australia, Series number A2408, Control symbol 9/15 PART 1

12. Letter 9/8/1938 from DTS to DE. National Archives of Australia, Series number A705, Control symbol 9/15/5

13. Correspondence file 05/10/1938 reference SAB 11389. National Archives of Australia, Series number A2408, Control symbol 9/15 PART 1

14. Correspondence file 27/10/1938 reference A/CAS. National Archives of Australia, Series number A2408, Control symbol 9/15 PART 1

15. Correspondence file 02/02/1939 CAC Resident Technical Officer reference 075/39. National Archives of Australia, Series number A2408, Control symbol 9/15 PART 1

16. Correspondence file 20/04/1939 reference 250/34/17S. National Archives of Australia, Series number A2408, Control symbol 9/15 PART 1

Ceres book now into layout

The Ceres book is in the final stage of production before going to the printers – layout.

And I’m discovering that layout takes a lot longer than expected! The most time-consuming part of layout is captioning the photos. What do they show, when did it occur, and have I obtained permission from the photographer? Getting these details correct actually takes an amazing amount of time.

The good news is that I’ve finished page layouts for chapters 1 through to 6 and I’m on the last chapter now. But this chapter is taking longer than the others, as it covers the history of each individual Ceres aircraft (all 21 of them).

Here’s a preview above – and yes, the book includes colour profile artwork by Juanita Franzi Aero Illustrations!

Ceres book progress

A brief progress report on the CAC Ceres book…

I’ve received a test-print from the printers, so I can check the layout, typeface, colour, sharpness, etc. Great to see the book in the flesh for the first time! The software I’m using for the book design seems to do the job quite well.

The plan is to have it finished by September.

Famous pilots at 2SFTS

A recent discussion on the “Friends of the Wirraway” group on Facebook required some  sleuthing to identify where and when a photo of 3 Wirraways (shown below) was taken.

The photo appears on page 23 of Stuart Wilson’s book ‘Wirraway, Boomerang & CA-15 In Australian Service’ but his caption merely reads “A flight of three Wirraways (A20-78, 82 and 101) from an Operational Training Unit. All are Mark II aircraft, ordered under the CA-3 contract, sixty of which were delivered to the RAAF between February and September 1940”. He doesn’t identify the unit or the date, so that didn’t help.

The photo is also in the collection of the Australian War Memorial, but I have found that AWM photo descriptions are sometimes incorrect, so I wanted to check if their description was accurate. AWM states  that the picture was taken in September 1943 at No. 5 Service Flying Training School (based in Uranquinty, NSW). They list the pilot of A20-82 as Flight Lieutenant Dick Cresswell and the pilot of A20-78 as Flight Lieutenant Blake Pelly.

But on checking, the date of September 1943 can’t be right, since Dick Cresswell was a Squadron Leader by this time, and he was sitting in Port Pirie awaiting a court martial at around this time. So I needed to go back to the basics to solve the “when and where” mystery of this photo.

The service histories of the three aircraft in the photo reveal that they all served at No. 2 SFTS at Forest Hill (Wagga) between September 1940 and April 1942. Cresswell and Pelly were both at 2SFTS during this period (according to ‘Mr Double Seven’, the biography of Dick Cresswell – which can be downloaded from the Air Power Development Centre website). So now we know the unit where the aircraft were serving (No. 2 SFTS) and the period during which the photo was taken.

James Kightly suggested looking into the details of the markings on the aircraft, and this indeed sheds more light on the timing. The yellow cowlings on the aircraft were ordered to be added in December 1941 and the red circles in the national markings (roundels) were ordered to be removed in July 1942, so this narrows the date of the photo to between December 1941 and April 1942.

So now we can confirm that this photo of two famous pilots (Cresswell rose to Wing Commander and Pelly rose to Group Captain) flying Wirraways was taken when they were at No. 2 SFTS, some time between December 1941 and April 1942.

Several other photos were taken during this sortie, here is another:

A dramatic view of Wirraways A20-78, 82 and 101 from No. 2 Service Flying Training School. Note that A20-78 (far right in this photo) is wearing a camouflaged lower cowl and yellow upper cowl.