Within the pages of the Headmark journal are historical articles about little covered areas of the RAN’s history. A fine example of this is an article appearing in Headmark 127 (2008) by ANI member Dr Tim Coyle on RAN pilot training in the 1920s.
Royal Australian Navy Pilot Training & Aerial Hydrographic Surveying in the 1920s
Aviation in the RAN began with the ordering of six Fairey IIID floatplanes in 1920 as ‘Australian Naval Aircraft’ to operate in the survey role. With the formation of the Royal Australian Air Force (RAAF) in 1921 the aircraft were transferred to the RAAF and based at Point Cook, Victoria. Although intended for operations from naval ships only one aircraft – attached to HMAS Geranium – was actually deployed in this role.
To staff the naval air arm, a small number of naval officers underwent pilot training with the RAAF at Point Cook. The aviation career of one of these officers, Lieutenant Vincent Kennedy RAN, is illustrative of the short-lived naval pilot program of the 1920s, which culminated in the pioneering use of aircraft for RAN hydrographic surveying off the North Queensland coast.
Lieutenant Kennedy entered the Royal Australian Naval College (RANC) at Jervis Bay in 1915 and, as was normal practice at the time, undertook his senior midshipman training in a Royal Navy ship, the battle cruiser HMS Tiger. In 1924 he underwent a naval observer’s course at Point Cook and was appointed to the survey ship Geranium as observer in the Fairey IIID seaplane attached to the ship, which was operating on the Great Barrier Reef conducting hydrographic surveys for the preparation of maritime charts. The following year he volunteered for the ‘Australian Fleet Air Arm’, together with Lieutenants Geoffrey Carter and David Ross, and undertook flying training and subsequent service with the RAAF until 1928 when he elected to remain in the RAN as an observer, rather than transfer to the RAAF as a pilot.
Kennedy’s flight training began on 2 February 1925 and he soloed on 23 March with a total flying time of 15 hours 10 minutes. His first excursion from the confines of the Point Cook aerodrome occurred on 30 March when he flew as a passenger to Port Melbourne and return. A further flight to St Kilda and return on 9 June was also as a passenger in a formation flight. His first flight solo beyond the Point Cook aerodrome area was to Melbourne and return flying a DH9 on 4 September. This and subsequent flights required very little navigational expertise because of the prominent urban landmarks over which he flew. Two training flights comprised triangular courses Point Cook – Winchelsea – Geelong – Essendon – Point Cook, which were completed by the end of September.
Other flying serials included general aircraft handling comprising circuits and landings, forced landings, aerobatics and formation flying. Kennedy then began to train in military applications such as Lewis gun practice, photography, visual signalling and bombing. He underwent a photography test over the Point Cook airfield on 12 November and a visual signalling exercise with the light cruiser HMAS Sydney steaming in Port Phillip Bay the next day.
‘Cloud flying’, a rudimentary and inherently dangerous ‘blind flying’ technique, was undertaken as part of the flying training syllabus. Approximately 90 minutes was practiced in several flights within the confines of the aerodrome.
Kennedy’s ‘air pilotage’ test was the first navigation-based examination, and was conducted over three flights on 24 November in a DH9A. The first test comprised a flight of two hours duration at a height of 2000 feet on a course ‘as required for test’. This flight was logged with Kennedy in command and accompanied by a Flying Officer Simpson. No detail of the route was provided. The second flight, 55 minutes at 2400 feet, with Kennedy flying solo, was carried out over the route Point Cook – Lake Durdiwham – Sunbury – Essendon. Kennedy landed at Essendon at 1520 but immediately took off for the return to Point Cook at 2000 feet with a 20 minute flight time. The outward flight was a north-westerly track to Sunbury thence south-easterly to Essendon airfield. These flights were not geographically challenging because a road and railway intersected at Sunbury and Essendon airfield was similarly well-marked. The return flight had the advantage of the city of Melbourne and the western edge of Port Phillip Bay marking the route.
Kennedy’s total aeronautical experience at the end of November 1925 was 119 hours, so the exercise would not have taxed his general flying skills despite his limited exposure to ‘cross-country’ flying. His total hours were accumulated through experience on five aircraft types: the Avro 504, the DH9, the DH9A, the Fairey IIID floatplane and the SE5A fighter. The Avro 504 was a twin-seat basic trainer on which pilots received elementary flying instruction and first soloed. The DH9 provided training in military skills such as gunnery and photography as well as familiarisation with a heavier, more advanced aircraft. Experience on the Fairey IIID was required for future seaplane flying on hydrographic operations; and the SE5A was a fighter aircraft used for aerobatics training. The requirement to convert onto each of these aircraft types required extra dual flying, solo tests and subsequent flying practice.
Kennedy increasingly flew the Fairey IIID floatplane in navigation exercises in the Port Phillip Bay and Mornington Peninsula areas. Flights also comprised naval cooperation and military practice such as the 1 June 1926 ‘bombing Submarine J2’. Toward the latter part of World War I, trained observers carried out the military skills of reconnaissance, gunnery, bombing and signalling in multi-crewed aircraft; however, with the postwar disbandment of the observer category in the Royal Air Force and RAAF, pilots were required to be proficient in these skills. When the RAAF developed a maritime reconnaissance capability in the 1930s, these duties gradually reverted to the re-invigorated observer category.
On 20 August 1926 a crew of three, comprising Kennedy, a Lieutenant Carter and RAAF Corporal Haynes, departed Point Cook in a Fairey IIID for the RANC at Jervis Bay – via Paynesville and Eden – to support naval exercises. The crew arrived at the college slipway on 22 August after a total flying time of six hours. In addition to the several exercises flown in support of RAN ships, such as observing the fall of main armament shot and carrying out dummy attacks on the ships, the crew undertook a two hour 45 minute reconnaissance from Jervis Bay to Port Hacking and return. Port Hacking is located to the south of Botany Bay in the present Sydney metropolitan area. This return flight demonstrated the ability of a floatplane crew to reconnoitre an area of coastline to a radius of 90 nautical miles (nm) and return to base. In this context of maritime reconnaissance the aircraft could have alighted on Sydney Harbour, refuelled, and continued for a further 90nm, thereby covering the approaches to Australia’s premier naval and mercantile port.
Aerial Hydrographic Surveying
Following the 1925 government decision to construct a seaplane carrier for the RAN, a complementary requirement arose for suitable aircraft to operate from the ship. The type selected was the Supermarine Seagull III single-engined, wooden-hulled, biplane amphibian.
The aircraft arrived from the UK in mid-1926 and joined No. 101 (Fleet Cooperation) Flight commanded by Flight Lieutenant A. L. Hempel. The first three aircraft were assembled and transported to Bowen in north Queensland for hydrographic surveying duties, which had begun with the Fairey IIID seaplane in 1924. The survey flights began in September 1926 and continued until the end of 1928. Operations started and ended on the beach at Bowen with the Seagulls taxying into the water on their wheels before retracting them manually for take-off and lowering them at the conclusion of the flight when returning to the beach.
Two methods were employed on the aerial surveys. One involved sketching the reefs and islands from the air, which was a rapid means of initial surveying. This was followed by a small boat team, which refined the sketches and took depth soundings. The other method involved aerial photography in which, to fix the position of reefs in relation to each other, markers were dropped onto the reefs and photographed, ensuring that the markers appeared in both prints. Position fixing by both methods was carried out by the aircraft alighting on the water adjacent to the reefs and the observers taking sextant readings to measure angles from prominent shore geographical features.
Pilots used an Aircraft Plotting Diagram (APD) to sketch details from which bearings and distances could be calculated. The APD featured a centrally printed compass rose and graduations for latitude along the left hand edge. The observer drew meridians of longitude and entered the latitude band for the area of operations. The features under survey were then sketched using the centre of the compass rose as a reference point.
Kennedy and Lieutenant Joseph Hewitt RAN began hydrographic operations on 27 September with a three hour 30 minute flight in Seagull A9-3 from Bowen to the Barrier Reef and return. The flight took oblique photographs and carried out general reconnaissance. Flying then proceeded on a daily basis with flights of approximately three hours 30 minutes covering distances up to 100 nautical miles from Bowen surveying the many reefs in the vicinity of Hook, Cumberland and Holbourne Islands flanking the Whitsunday Passage, and proceeding as far as Flinders Passage. Sketching was the primary surveying method carried out on these flights.
On 18 March 1927 Hempel, Kennedy and an aircraftman left Bowen to fly south to take part in a series of RAAF ceremonial flights on the occasion of the opening of the provisional Parliament House in Canberra on 9 May by the Duke of York. A second Seagull was probably in company. The route was coastal via Styx, Bundaberg, Brisbane, Port Macquarie to Pittwater, north of Sydney, thence inland to the RAAF base at Richmond where the aircraft arrived on 24 March after a total flying time of 17 hours. Two days later the aircraft took part in the escort for the battle cruiser HMS Renown carrying the Duke and Duchess of York who were arriving for the opening of parliament ceremonies. Following some local air practice in the Sydney area, which included artillery cooperation, Hempel and Kennedy flew the Seagull to Point Cook departing 17 April and arriving four days later.
The Seagulls then returned to north Queensland to continue surveying. Kennedy in A9-4 arrived at Gladstone on 18 July and carried out a series of surveys until 8 August using the photographic technique along the reefs adjacent to Bunker Gap, Lady Elliot Island and the islands in the region of the Capricorn and Curtis Channels. Kennedy flew back to Bowen and carried out photo reconnaissance flights in the previously-surveyed area until 2 December when he returned to Melbourne while Seagull surveying operations continued until the end of 1928. Kennedy’s last flight as a pilot took place on 30 May 1928 when he did 50 minutes dual aerobatics practice in an Avro trainer. All his subsequent flying was as an observer operating from RAN cruisers, the seaplane carrier HMAS Albatross and Royal Navy aircraft carriers. He was seconded to the RN (July 1928 to January 1929 and May 1930 to May 1932) flying from the aircraft carriers HM Ships Hermes and Glorious respectively.
North Queensland Hydrographic flights in 1928
With the conclusion of the air support to the hydrographic effort in North Queensland, Lieutenant Hewitt, officer-in-charge of 101 (Fleet Cooperation) Flight, reported on the operations. In addition to the activity detailed in connection with Kennedy’s attachment, the Flight carried out a number of Outer Barrier Reef surveys that were pioneering in the use of aircraft and innovative techniques for hydrographic surveying.
The area of the Reef to be surveyed comprised approximately 5,000 square miles, to a distance of 45 miles offshore. The object of the survey was to locate passages through the reef for naval defence and to mark the inner and outer reef edges for the compilation of a reconnaissance map showing the grouping and relative positions of the various reefs.
The methods considered for the survey were mapping from vertical or oblique photographs and plotting from ‘navigationally controlled aerial traverses’. Vertical photography was discounted because of the scattering of the reefs, the extremities of which could not be framed in single photographs, while no suitable oblique cameras were available. Therefore the previously untried navigationally-controlled traverse method was adopted which gave a relatively accurate representation of the reef shapes and positions. The procedure was to fly pre-determined compass courses as accurately as possible while the observer took bearings on prominent points of the reefs. The observer also plotted the courses and the bearings on charts, sketched the reefs and photographed them.
In practice the traverse method provided mixed results for which the quality of the instruments used was blamed. Added to this was constant bad weather and initial unfamiliarity with the immediate area. Dead-reckoning navigation became progressively less accurate over 50 miles from the starting point of the flight as errors inherent in windfinding, instrument errors and flying accuracies compounded, particularly if there were several course changes required for each flight. To reduce the number of course changes, a series of ‘control points’ was established to serve as starting points for each traverse flight.
Instruments used for the traverse flights were two Type 253 compasses (for pilot and observer), an ‘aneroid’ (altimeter), an air speed indicator (ASI), a Wimperis wind gauge bearing plate, a marine sextant and a chronometer. These instruments were inadequate for the exacting standard of navigation required for the traverse surveying flights. The 253 compasses were non-aperiodic and would have been subject to turning errors. Because of the lack of specialised equipment, the ‘aneroids’ and the ASI could not be calibrated for the local environment. Laboratory testing for the ASI was not available in Australia at that time and calibration in the field could only be carried out by flights upwind and downwind over a known distance. Precise altitudes could not be flown because of the inaccurate calibration and also because the instrument dials were marked in units of 200 feet. While this was adequate for normal service flying, when precision height-holding was not necessary, the need for accuracy in the aerial survey application challenged the technology available at the time.
Hewitt estimated the errors in reef positions to average three miles, which could have been reduced by one-third with accurate instruments. He regarded the overall aerial survey method as carried out by 101 Flight as insufficiently accurate to definitively fix reef positions for marine navigation, so more traditional surface surveying procedures were required to follow-up the aerial surveys to refine results.
A fully annotated version of this article is available at:
https://navalinstitute.com.au/wp-content/uploads/2014/04/headmark-127.pdf
Dr Tim Coyle enjoyed a 37-year career in the Defence Intelligence community both as a civilian analyst and an active naval reservist. As a civilian he specialised initially in regional air and maritime operational analysis and latterly supported Australian government agencies as technical adviser in international arms control and analysis. As a naval reservist Tim undertook a variety of intelligence appointments culminating discrete weapons technical analysis. He qualified as a Russian linguist at the Defence School of Languages. Tim is the Australian Naval Institute Book Review Coordinator. His interests include the Russian and French languages, naval history and strategy and international affairs more broadly.
