Seagrove Airfield – Franklin’s WW2 secret air force base

Almost eighty years ago, during WW2 airspace above Waiau Pa was filled with Dauntless dive bombers. At its busiest, the district’s air force base was home to 27 aircraft.

    In 1942, soon after Japan came into the war, New Zealand constructed an aerodrome at Seagrove for the RNZAF as a fighter station for the defence of Auckland City and harbours. The homestead and surrounding farmland were compulsorily purchased from the Clark family, whose property was called Seagrove. In all, 632 acres under six titles, were taken.

    Surveying was undertaken in April and building started in May. The construction was completed finally at the end of 1942. The original estimate for establishing the base had been £121,000 but the final bill came in at £225,000.

    The first accommodation became partially available in June but bad weather delayed completion with the result that the No. 15 Squadron stayed at Seagrove from December ’42 until June ’43, as did the Kittyhawks and Harvards. At this stage Seagrove was used as a training base.

    The location was at an altitude of three feet above mean sea level, on land bordering the Manukau Harbour at the far end of Seagrove Road. Today, if you want to locate the centre of the airfield just travel down to very end of Seagrove road and there you will find a sizable monument to its presence.

    The main runway was longer than Ardmore’s at 5250 feet in length. The book “Franklin Remembers” by Keith and Nona Morris has an excellent chapter about the station including aerial and ground pix of the Dauntless and pilots.

    In its heyday the airfield consisted of two runways with sealed metal surfaces. An 8ft drainage canal was dug around the perimeter and spoil from that was used to create a stop bank to protect the runways from spring tides.

During the construction period, over 60 trucks from Stevenson’s Drury quarry and from Parry’s Patumahoe quarry (now the location of Wright’s Watergardens) created dust clouds as they roared down the unsealed Seagrove Road with loads of metal.

    Initially the authorities named the base “Karaka” but it seems that subsequent phonetic confusion with Omaka (an air force base near Blenheim) and a plea from the Clark family for whom “Karaka” meant something else, led to the aerodrome being renamed “Seagrove.”

    Some time before the station was complete it had already become operational. No.  15 Squadron had originally formed at RNZAF Station Ohakea, but the squadron had moved up to Seagrove on the 10th August 1942. The squadron, flying P-40E Kittyhawks, flew in defence of the Auckland region for around two months, before they were posted away, and the newly formed No. 17 Squadron  (also flying Kittyhawks) replaced them.

    No. 17 Squadron remained at Seagrove from October 1942 through till the 15th June, 1943. At this stage the base of fighter protection for the Auckland region moved from Seagrove to Ardmore.

    A new dimension for the aerodrome came in May 1943 when American forces arrived in New Zealand. The US Marine Corps dive bomber squadron MAG-14 (Marine Air Group 14) was offered the used of Seagrove having come to NZ from Guadalcanal. MAG-14 remained at Seagrove until July 1943, during which time many other US aircrew members were stationed her whilst on rest and recreation (R&R) following service in the Pacific. Hundreds more US servicemen spent time at Seagrove, enjoying R&R. The RNZAF base was enlarged for them and for some months, also became the home to RNZAF No. 25 Squadron, formed in July ’43.

    When the US Squadron left Seagrove they left nine of their Dauntless dive bombers behind for the newly formed RNZAF No. 25 Dive Bomber Squadron.

    This squadron was under the command of Sgn Ldr Theo MacLean de Lange. On arrival, in June 1943, he found the station to be sparse and under-equipped, with few tables and no cooking or eating utensils. The CO’s house that he was to occupy just had a double bed, a table and four chairs, with an outside meat safe. Luckily as No. 25 Squadron, which was made up from members of the disbanded Army Co-operation squadrons based at Onerahi and Milson, de Lange’s equipment officer (F/O Baker) was able to obtain most of the equipment needed from RNZAF Onerahi which was closing at the same time. The RNZAF had ordered a quantity of 206 A-24 Banshee dive bombers to equip four new squadrons. However, these were delayed and then the US service through which Lend Lease acquisitions were made, changed from the US Army Air Corps to the US Navy. Thus, instead of the army version, the Banshee, the RNZAF was allocated the navy version, the SBD Dauntess.

It took some time to get the aircraft serviceable which probably explains why the USMC left them. The first did not get airborne till the 5th August, 1943.

After 25 Squadron had completed their training, they were ready to depart to Espiritu Santo in the forward area in the Pacific. On 6th January, 1944 the squadron flew 18 Dauntless in a ‘V’ formation over Auckland as a farewell flypast, it was the largest formation seen in New Zealand skies till that date. The squadron then did a jungle training course at RNZAF Swanson, and they departed Seagrove finally on 30th January to fly to Santo aboard an RNZAF C-47 Dakota.

Their aircraft were to remain at Seagrove (they were picking more up waiting for them at Santo), and the next dive bomber squadron, No. 26, was now formed. They too began to train at Seagrove. However, both the war situation and the manufacturing situation changed, and the RNZAF decided to scrap plans for the four dive bomber squadrons. No. 26 Squadron had only done a matter of weeks on Dauntless conversion, before they were disbanded and reformed as a Corsair Squadron at Ardmore.

Once No. 26 Squadron was gone, squadrons from nearby Ardmore used the sea just off Seagrove for a firing range for a time, before this ceased.

For a period, Seagrove was the site of one of the Initial Training Wing schools, where new intakes into the RNZAF would learn the basics of RNZAF life before going onto the more specific training courses.

This squadron left for overseas early in 1944, after which Seagrove functioned only as a satellite landing ground to the RNZAF station at Ardmore.

When the war ended Seagrove fell into disuse although a Radio Research Station remained on site for many years. Everything in the way of buildings would have been removed when the station closed down and the area reverted to farmland. All building materials were in extremely short supply from 1945-1950 so everything would have been in great demand. Archives of the Auckland Car Club magazine show references to speed events held at Seagrove, around 1950. Presumably, there would have been sealed taxiways that could have been used in conjunction with the runways to create a motor circuit. Also, a number of events were ‘sprints’ which were just speed in a straight line.

Until the more recent introduction of sophisticated radar systems, Seagrove was a visual reporting point. When airline pilots could actually see the old airfield’s radio masts, they reported to Auckland Air Traffic Control who transferred that flight from radar to visual control.

What remains of RNZAF Seagrove today>?

On the property attached to a boulder, is a plaque which commemorates the 50th anniversary in 1992 of RNZAF Station Seagrove 1942-44 and the US Marine Corps, 1943. Also, there are memories,

By Megan Allan