The fire started in a hangar roof space near two planes at Norwich International Airport just before 10:00 GMT on Sunday and continued for 12 hours.
Watch manager Rob Burling said one of the two aircraft was removed amid concerns about the fire spreading.
An investigation is due to start.
Mr Burling said: "Had the roof fire taken a proper hold and caused complete devastation, the first plane would have been at risk.
"But thanks to the work of fire crews, damage was kept to a minimum, and we got the plane out in good time."
Mr Burling said the blaze was put out on Sunday night, but crews remained on site through the night "because of the nature and complexity of the incident".
Firefighters remained at the scene on Monday morning ahead of an investigation into the cause of the blaze, which did not cause damage to any planes.
Norwich Fire and Rescue Service said the cause was not thought to be suspicious.
A spokesman for Norwich International Airport said services were not affected.
"Complete devastation" was averted at an airport when a huge blaze broke out in a hangar and required 70 firefighters to bring under control.