Not carved but built up. A skin made up of long narrow planks over formers using 5mm expanded polystyrene (XPS) laminate flooring under lay sheet. Same for the wings. A technique not that far removed from how it can be done using sheet balsa.
The formers are all fixed in place over a "spine". In this case it is the EDF inlet and exhaust tube which is 3D printed.
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The nose/cockpit section is built separately and glued on once the main fuselage skin is complete. The wings are also simply glued on. It is one advantage of the right glue on XPS. A simple butt joint is as strong as the sheet itself.
It does take some time and practise to do well but the result is really light and remarkably rigid.
Just for fun? I built a whole range of Hawker post war jets all built in the same way and to the same 1/12 scale.
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It helps to be retired!