The Piasecki H-21 Workhorse design ensured the rotors at opposite ends of the aircraft did not clash.
It was developed from a prototype which was powered by a surplus Wright Cyclone engine from Flying Fortress bombers.
A spokesman for the Helicopter Museum in Weston-super-Mare said the H-21 is the first of its type in the UK.
The helicopter, serial number FR41, was built in Pennsylvania for the French Army Air Force and saw action in Algiers in 1956 during the civil war.
Once the restoration is complete it will go on display alongside another famous twin rotor helicopter, the Bristol Belvedere, which was built at Weston in 1960.
Work to restore a twin rotor helicopter nicknamed the "Flying Banana" because of its unusual kinked fuselage has begun.