The Sea King, which was carrying four crew members, made a controlled landing in a field near Ardrossan at 11.25am yesterday.
No one was injured in the incident.
Engineers from HMS Gannet, the helicopter search and rescue base at Prestwick, were later at the site assessing the aircraft, which was on its way to a training exercise.
Officers from Police Scotland were also at the scene as well as the local coastguard to help manage the high numbers of onlookers who had stopped to take pictures.
A spokeswoman said: "We can confirm that a Royal Navy Sea King Mark 5 helicopter from HMS Gannet made a precautionary landing just north of Ardrossan in a field adjacent to the Ardrossan to Largs road at approximately 11.25am after a potential technical issue was identified by duty crew members.
"The issue relates to observations noted by the crew of fluctuations in a temperature gauge.
"The landing was smooth and unhurried.
"At no time was there any danger to the aircraft, crew or the public."
It comes days after two people died in a crash in Norway invol-ving an air ambulance which was identical to the police helicopter that crashed into a busy Glasgow pub in Novem-ber, killing 10 people.
Helicopter manufact-urer Eurocopter confirmed that the aircraft which crashed at Sollihøgda, west of Oslo, on Tuesday, was an EC135, the type that crashed into the roof of the Clutha pub on November 29, last year.
Both victims were said to be among the ambulance service's most experienced personnel.
The cause of the crash remains unclear and an investigation has been launched.