The Soviet Union had a shortage of aluminium prior to the war, so aircraft designers often resorted to wooden construction. This made their fighters heavier than their all metal Western equivalents, which in turn is why Soviet designs were sometimes short of fuel capacity and firepower. The La-5 and La-7 series was derived from the awful inline engined Lagg 3 which had a wooden structure skinned with plywood and then fabric. Later as aluminium became more readily available Lavochkin replaced some wooden parts like the wing spars with metal ones to save weight. The La-5FN also introduced some metal plates on the sides of the fuselage and the wingroots to protect the plywood structure underneath from exhaust heat and groundcrew damage.
The post war La-9, basically an all metal airframe La-7, was so much lighter it could carry up to four 23mm cannons and enough fuel to almost double the range.
There's less work in the Las than most skins, not only is there a lot less rivets, but far fewer panel lines. If anyone wants a good starter project to get into skinning, the La-5 and 7 would be a good bet.
