09 September 2014

Mapping NZ Aerial Mapping

With yesterday's sad news that NZ Aerial Mapping is closing I thought it would be nice to take a look at the company's aircraft... and then on their website I found a wonderful company history which I have pasted around the photos...


On the 8th May 1936, New Zealand’s now oldest aviation company, NZ Aerial Mapping (NZAM), was officially founded by Piet van Asch in Hastings.

Starting out with a Monospar ST25 twin engine aircraft bought directly from the General Aircraft factory in Feltham, England (for ₤1,450), Piet managed to arrange contracts to photograph farms of prominent land owners in Hawke’s Bay. They had already put up a great deal of money for Piet to be able to travel to England, buy the aircraft and get the training necessary for the successful start of NZAM.

NZ Aerial Mapping's first aircraft, General Aircraft Monospar ST-25 ZK-AFF at Wigram on a wet day in September 1978

The Early Years

The first survey undertaken in New Zealand was for the Geological Survey which started on the 28th April 1937. The survey was of the Richardson Range in Otago and covered nearly 300 square miles (780 square kilometres) at 11,000 feet, yielding 843 frames of photography.

From then until the war years, NZAM grew slowly yet solidly. Initially work was generally carried out for the Department of Scientific and Industrial Research (DSIR) and the Public Works Department. In 1938, the first work was won from the Land & Survey Department (L&S), which necessitated purchasing a new camera. This was the beginning of a long and enduring relationship between NZAM and L&S, later known as Department of Land & Survey Information (DOSLI), and now Land Information NZ (LINZ).

The advent of hostilities in the Second World War saw NZAM take on a new and vital role. Under threat initially, having been targeted to be integrated into the RNZAF, Piet managed to keep the company separate and to grow it, taking on an ever-increasing workload with defence mapping projects.

By mid war, it became obvious that the Monospar would need help. With its limited ceiling, a bigger more powerful aircraft was sought and in 1943 a Beechcraft AT11 was added to the line up. By June 1944, NZAM had photographed a total of 25,570 square miles (66,200 square kilometres) for the war effort.

With the advent of the longer range and capacity of the Beechcraft, off shore surveys were a possibility. The first was in 1944 of Fiji, particularly the Suva Peninsula and areas at Lautoka. Since then, NZAM have worked in most of the Pacific Islands and have travelled as far as the Antarctic, Kathmandu, Vietnam and Thailand.

The Beech AT-11 Kansan ZK-AHO at Hokitika on 21 March 1977. On the day this photo was taken the Kansan had been on the job for some 34 years!

The 1950’s

During the 1950’s the company’s progress was in ground-based expansion. 1953 saw the introduction of Photogrammetry on the suggestion of the then Surveyor-General. Science graduate Brian Perry led the company in this field with a special kind of acuity and practicality which was confirmed by the carefully contoured maps his staff turned out down the years.

In a good month 8000 prints could be produced using the only three types of film available then. However it was still a tightly managed operation within the financial constraints of the Government, which continued to supply NZAM with the majority of its work well into the 1980’s.

The company’s premises in Russell Street had reached maximum capacity. Therefore in 1956 a custom designed headquarters on the corner of Avenue Road and Warren Street in Hastings was built, tangible evidence of the company’s progress.

This impressive building boasted its own central powerhouse, which provided the essential clean air and water for the photography. The installation of copper tanks and refrigeration and with the use of positive pressure, dust was shut out of all the areas where film was being worked. Dairy industry pumps were even used to suck the films and papers flat in the various enlargers and copy cameras.

This set-up was the envy of overseas visitors, providing cheap operation and played a valuable part in reducing dust on the film. In NZ this was of huge importance as NZAM keeps its film negatives forever, as opposed to the UK and Australia, which destroyed stocks after 10 years.

Piet’s insistence that the company ‘produce a high quality article’ kept him informed on research and development within the industry which saw equipment moving in and out of the company in fast succession. Three A8 Analogue plotters joined the company and were one of the survivors of the equipment movement era, remaining in use until well into the 1980’s. One in fact is still in use today by a former employee for the production of orienteering maps.

Throughout this decade, weather had a part to play as much as it is found today. Bad weather impacted on flying time and income on occasions but the usual high standard of product was maintained with an increase in the use of aerial photography being noticed in the 1950’s.

The 1960’s

NZAM worked on a number of projects during the sixties, one being the chain cover of all of NZ highways and the subsequent production of folders, which marked where every fatal accident was in order to make road improvements.

The most prominent project was for the National Film Units’ ‘This is New Zealand’ which was made especially for the NZ pavilion at Expo 70 in Japan. Three cameras were mounted in the nose of the Beechcraft enabling three screen stereoscopic viewing which won high acclaim.

With the introduction in 1965 of the longer focal length Zeiss cameras, city survey photography produced extraordinary detail. To view wires on a clothesline and shadows on the tarseal from overhead wires excited the NZAM staff. Some of this earlier imagery was printed on a product called cronopaque made by Du Pont. Supposedly indestructible, its Achilles heel proved to be the hot Hawke’s Bay sun if left in the backseat of a car too long!

Prior to the mid-sixties, NZAM had been trying to discover how to reduce the angle of coverage of the normal lenses that were available for the large-scale city plans Piet wanted so much to supply to the city engineers.

This ability to identify ground marks was only the start with special jobs flown twice, once with the wide angle cover to produce large scale contours which were then overlaid on the narrow angle enlargements allowing the photogrammetrist to only mark the odd fence corner to marry the two.

1965 also saw the introduction of halftones so that the city engineers and planners could superimpose information and take ammonia prints for contractors. The popularity of these saw NZAM producing more halftones than prints right into the 1990’s.

The company’s third aircraft, ZK-CDK started survey in 1964. Named ‘Matariki’ in 1967, this Aero Commander 680F provided an operating ceiling of 25,000ft – treble the camera to ground clearance of the Beechcraft in the high country and 20 knots faster. This aircraft was overhauled in 2003 after a year of ‘retirement’ and still provides a valuable survey platform for the company.

The higher ceiling of ZK-CDK resulted in the aircrew experiencing some cold temperatures in the winter of 1964 – and watching oil pressure gauges go below the minimum due to the oil in the pipelines up to the instrument panel freezing.

NZAM started using colour seriously for the NZ Forest Service photography in 1965. Following that a small length of Agfa 7 film was exposed over the Mt Tarawera eruption chasm from the Eagle survey camera, resulting in wonderful colours – the only drawback was that the film had to be sent to Europe for processing.

Forestry companies weren’t too interested in colour photography until 1967 when a full-scale survey was carried out over the Kaingaroa State Forest to enable studies of a fungus disease (dothystroma). This was quite successful although the Kodak film speed was marginal and when a faster emulsion was available, the Forestry industry became more involved in colour coverage.

The increase in work once again led to renewed pressure on space within the office premises and when the chance to purchase the neighbouring property arose in 1965, it was taken and the original builders’ yard house was converted with a lunchroom at the back and mosaic room at the front, which later was used for picture framing. The house still stands today and occasionally serves as a function and lunch room.

Towards the end of the decade, South Island farmlands were covered and the first flying coverage of the North Island was almost complete.

Aero Commander 680F ZK-CDK in three different schemes at Queenstown...
at Hokitika on 17 October 1982...
and at its home base at Bridge Pa on 23 January 2013

The 1970’s and 1980’s

With the arrival of the Rockwell Commander 690B in 1978, the need for two operational aircraft at higher altitude was met. The Beechcraft was flown to Hobsonville airport in January 1982, where it was collected by NZAM 39 years earlier, and taken to MOTAT for permanent display in Auckland where it can still be seen today.

A notable aerial survey project was that of Greater Christchurch in early 1973 at a 1:10,000 scale. This series of mosaics on the national grid were extremely beneficial to the Police in order to base their security plan on with the 1974 Royal visit to the Tenth Commonwealth Games in Christchurch.

Forestry mapping for Lands and Survey Department continued as did the forestry coverage for both North and South Islands. An unusual assignment was thermo vision work carried out between Taupo and Rotorua using the first two hours of daylight and the last two before dark. This avoided the main heat of the sun and allowed the recording of 2 degree ground temperature changes for the DSIR. The work enabled hotspots to be recorded and therefore avoided for road extensions and cable locations.

The first testing of the DSIR Hasselblad cameras for the Remote Sensing division took place as well as various magnetometer surveys for the department.

1975 saw the purchase of an expensive Kodak Versamat processor to handle the longer lengths of 9 inch film and the testing of 500ft Kodak +X film which at last enabled even development of each and every exposure. The 48 x 48 copy camera also saw major modifications to allow it to make enlargements of the 9 x 9 film in negative size or portions thereof up to 67 diameters.

When Piet bought the 12in Zeiss camera he arranged delivery of a ‘family’ of cameras, which included a 6in RMK 15/23 for each of the aircraft. These cameras with their Pleogon lenses were the price of a house each and the first arrived at the end of 1975 for use in the Aero Commander.

The first replacement for the A8 plotters from Wild, which served the company well for a quarter of a century, arrived in 1984 and was analytical instead of analogue. This BC1 provided digital data stored on tapes or discs and allowed plotting within 20 minutes of setup as opposed to between 2 to 4 hours on the A8.

Piet retired as managing director in 1980 but remained as chairman, and to fill his one-man position resulted in the creation of two joint managing directors, one of which was Piet’s only son, Hugh.

A revamp of the Hastings offices was undertaken in 1982-83 with new paintwork, the installation of a new fire alarm system, new roof and film vault to accommodate all the nitrate-based films that were recopied on safety base modern high resolution film.

An unfortunate accident on 26 June 1986 saw the first NZAM aircraft, the Monospar ZK-AFF, destroyed in a fire at the Bridge Pa Aerodromme. The likely cause was thought to be a static discharge of electricity during refuelling. Only months short of its fiftieth year in operation with NZAM, one of the salvaged wooden propellers is still on display in the Hastings office.

Turbo power... Rockwell 690B ZK-PVA - the glue plane - at Bridge Pa on 20 February 1985.

The 1990’s and into the 21st Century

The previous decades saw the growth of an exceptional company under the guidance of an equally exceptional man. Sadly Piet passed away in October 1996, and even today, he is still strongly associated with NZAM through staff and acquaintances who still talk of his achievements.

The ’90’s saw many changes for the company necessitated by the digital era and the downturn in government and local authority work due in part, to the increase in the ‘tender and do’ market.

The merger in 1993 between computer based land information company Aeroplan and NZAM saw the introduction of not only advanced computer technology and the necessary staff, but the company’s first foray into geographical information systems (GIS).

Hugh Van Asch and a number of remaining shareholders still held responsibility on the Board with the new owner, Craig Atchison. Through Craig’s ability to bring the ideas into the company and the willingness of staff to bring them to fruition, NZAM continued, albeit in some hard times, through this decade.

The advancement in technology heeded the need to move the majority of the operation to Auckland to capitalise on the increased market and staff availability. The remaining lab and photo sales worked with a staff of only 3 at times over a period of years until the return of the main operation in 2002.

With the company still owning the purpose built facilities at Hastings and Bridge Pa it was therefore decided by the Board to return the company to its original home base. The lifestyle that the Hawke’s Bay offered over the major cities meant that staff were more readily available and improvements with technology no longer restricted access to the data and subsequent markets.

The operating fleet of the Aerocommander 680 and the Rockwell 690 were complemented with smaller lower level aircraft like the Cessna 205 and Piper Aztec. When the 680 was grounded for a year in 2002, it was up to the 690 to cover the workload that was spread between NZ and Australia due to a merger with an engineering company based in NSW.

Cameras were vastly complimented by the purchase of an LH Systems RC30 which provides image motion compensation and automatic exposure control. Added to this is airborne DGPS survey technology and the flight planning software that provides superior results.

Film has also improved greatly over the years and the company changes between AGFA and Kodak dependant on who is manufacturing the most superior and cost effective product at the time – a policy firmly installed by Piet himself.

There are now digital cameras operating in aerial survey, and there are various other techniques for aerial imagery such as satellite imagery and airborne laser scanning.

This decade saw the ownership of the company change for better and worse – the large shareholding purchase of the ex-state owned enterprise Terralink was envisaged to provide a complete one-stop land information stop. The separation of the units giving TIL ownership of the GIS components and NZAM aerial survey and intensive photogrammetric projects like forestry, led to the demise of the idea.

Reverting back to full NZ ownership in 2003 saw the company focus once more on core activities. Vast improvements were made especially in photogrammetry which had not maintained an up-to-date presence due to the focus on GIS. Complete new Helava suites were purchased with all the latest software enabling more computer processing and less human intervention. The company purchased its first roll-film scanner and now operates a complete in-house solution, from aerial survey right through to the end photogrammetric and image product.

Rockwell 690A ZK-PVB was added to the fleet in March 2000. It is seen here at Auckland on 15 March 2011
Also added to the fleet more recently was Cessna 402B ZK-PVC at Bridge Pa on 23 January 2013...
and Cessna 207A Stationair 8 ZK-SEU at Bridge Pa on 27 January 2012.


  1. Thanks for the post Steve.

  2. Always thought the Monospar would make a nice flying model in celebration of its aviation history in New Zealand. Have some copied documents from NZAM on the Monospar and a nice photo too. Have read their NZAM book a number of times, great history and pioneering. Thanks Steve.

  3. Sad to hear (5 years late) that NZAM has gone. I moved to NZ from UK in 1993 to replace Fred (German photogrammetrist who left to run his own service). Have fond memories of my time in the company especially with Eric (Jock) who sadly passed away after I left) and Alan McPherson...brilliant bloke! Very good memories.