An aviation club based at Davidstow Aerodrome near Camelford is counting the cost after being targeted by an arsonist on Tuesday night.
The hangar at Davidstow Flying Club was set alight at around 10.45pm resulting in eight or nine aircraft being destroyed in the blaze, which were mostly microlights.
Six fire appliances from Delabole and Launceston Community Fire Stations attended the incident.
Fire crews, some wearing breathing apparatus, used three main jets and one hosereel jet to extinguish the flames.
The police and fire service carried out an investigation at the scene on Wednesday.
The arson attack has left members devastated.
Graham Skinner said: “Davidstow Flying Club unfortunately has been struck again by an arson attack in which eight or nine aircraft have been lost, which is to be confirmed.
“The individual who has done this does not understand the loss, or its consequences.
“One day when something like this visits his or her door they will. Aviators are passionate people putting their love of the air high on their life list.
“Many of us have worked hard and given many many hours to be able to be called an aviator and be privileged to own your own aircraft. I cannot understand the mentality of this individual who just wants this to cease and stop others from participating in their love.”
Member Geoff Nudd, who lost his Ikarus C42 in the arson attack, said: “Several aircraft lost including mine. It’s devastating for everyone involved.
Ness Maddock, who is also a member of Davidstow Flying Club, added: “I hope karma gets the person responsible.
"The upset, anger and the devastation it has caused for all of us effected by it is unmeasurable."
Courtney Chambers said: “This is another devastating tragedy to a wonderful airfield and it’s dedicated members.”
A spokesman for Cornwall Fire and Rescue Service said: “Fire appliances from Delabole and Launceston Community Fire Stations were mobilised to a report of an aircraft hanger on fire.
"When they arrived on scene, they could see flames and smoke issuing through the roof and requested a further fire appliance, which was sent from Launceston.
“The fire involved a hanger, measuring 70 metres by 10 metres, containing light aircraft and was extinguished by the fire crews, some wearing breathing apparatus and using three main jets and one hosereel jet.
“The cause of the fire is suspected arson and the incident was left in care of Devon & Cornwall Police.”