The Great North Air Ambulance Service was called to the location in Darlington after a woman fell into the side of the structure while in her garden last night, Monday August 13th.
She sustained substantial cuts to her arm and had lost a lot of blood.
The GNAAS crew used torniquets and specialist blood clotting dressings, the same as usually seen in battlefield incidents to try to stop the blood loss.
The patient was then transferred by road ambulance to the helicopter, which had landed at the nearby Terrotorial Army centre.
She was flown to James Cook Hospital in Middlesbrough for further treatment.
The flight from Darlington to Middlesbrough took eight minutes.