The Sky-Log system is possible and cost effective on flat terrain thanks to the self-propelled carriage. 

Cable Yarding Sky-Log
Hauling on flat terrain

 20 tons excavators amphibious. 

 18 mt. masts without extra anchors

 Main winches with 350 mt. cables length.

 Controlled remote cart mounted on sheaves.

 Controlled remote rotored Grapple.

 Radio set with camera.

Exploitation of flat terrain is now cost effective thanks to the self-propelled carriage.  On swampy terrain, ‘long track’ excavators are used and it ensures good flotation and mobility.

 Using 20 tons excavators, the ‘stick’ and ‘bucket’ are removed amounting to reduction by 6 tons the weight of the excavators. This enables the movement of the excavators while maintaining the cable tension.

 In the swamp, counterweight is removed from the excavator which enables good flotation.  In swampy terrain, 18 meters masts are used to maintain a hauling distance of 350 meters between the excavators.

 Once the excavator is in the swamp, a clamp is installed to the foot of the mast so trees are well placed before pressing the mast.