Cook the pasta in a large saucepan of salted boiling water according to the packet instructions until al dente. Drain thoroughly.
Meanwhile, put the courgettes in a large bowl and toss with 1 tablespoon of the oil. Heat a ridged griddle pan over a high heat until smoking. Add the courgette slices and cook for 2–3 minutes on each side until lightly charred and tender.
Return the courgette slices to the bowl. Drizzle with the remaining oil, scatter over the lemon thyme sprigs and squeeze over the juice from the lemon half. Season with salt and pepper.
Drain the pasta thoroughly and add it to the bowl with the feta and olives. Toss well to combine and serve the pasta immediately.