Brian Williams managed to get his home-built Stoddard-Hamilton Glasair SH-2R down safely in Macleans Reserve, Bucklands Beach, at about 2.45pm on Sunday.
Mr Williams, who was flying from Taupo to the North Shore Airfield, said he was a “lucky man” after touching down.
The Civil Aviation Authority (CAA) hopes to establish the cause of the precautionary landing after it receives a full report from the pilot.
CAA spokesman Bill Sommer told the Times an initial report obtained from Mr Williams on Sunday was that the engine started to “run rough”, so he looked for a spot to put down.
He describes media reports at the time of the incident, which blamed a lack of fuel, as “speculation”.
Mr Sommer says the CAA will not be sending a team to the site.
“We will get a full report from the pilot and investigate from that the prime reason for the forced landing,” he says. “One advantage is that we have a live pilot there compared with a fatal accident.
“The purpose of us investigating is to determine the cause, not assign blame. We want to know why he needed to land.”
Mr Sommer says the engine will be overhauled and it should be possible to find out whether the incident was the result of a mechanical fault.
“We would expect to sort it out in a couple of months once the information is flowing.”
A New Zealand Police statement issued on Sunday said: “As the pilot approached the Eastern Beach area he developed engine problems so decided to land in the reserve which is very large.
“Apart from propeller damage the plane appears to be undamaged. An ambulance attended but the pilot did not need to go to hospital.”
Seven officers from Howick police attended the scene, mainly to ensure people were kept at a safe distance from the aircraft.
Sergeant Kylie Newton says: “We had no concern for the public as there were no fuel leakages.
“But there were a lot of curious onlookers, some seen standing and sitting on the plane and taking photos, which was a concern for us.”
After arriving at the scene at 2.50pm, Mr Newton says police left at about 4.50pm.
“We decided that as a community service we should help the pilot, so we delivered him back to the North Shore Aero Club.”
Howick Fire Service, which was already attending a fire at Otara, received a call to the incident.
Local fire service volunteers and the Mt Wellington brigade were first to the scene.
The Mt Wellington team left when the Howick brigade arrived.
“We were there for about half an hour,” says John Searle, Howick fire station officer. “We left once we saw that the site was safe – fuel turned off and the power off.”
