Why chase someone that far? It should have been obvious he didn't want to fight for whatever reason. Low fuel, ammo, had damage....etc. I too would have turned back to collect your scalp because it shows your so desperate for a kill, you'd go to any means to get one and probably attempt to vulch a guy landing.
I've chased guys as far as 5 sectors before in inferior planes purely in spite of them running. Most the time they run is because you saddled them, not because they have low anything.
Few weeks ago, this pony tried to B&Z Pick me near my base at a quiet fight between two northern bases. I eventually ended up chasing him for 20+ minutes across 4 sectors until he finally tried to land at some base deep in his territory. I vulched him on the runway as he was coming to a stop which made it all worth it.
