Boeing has done a great job at stretching the basic design of B737.
I was looking at the latest 737 family that are currently in service, the B737-800 and 900 series look proportionally correct, however, when I look at the -700 or -500 series, I can't help but think how disproportionally big the tail fin is! It looks way too big for the size of the fuselage. If you look at the AIRBUS A320 family, from A318/319/320/321, at least to the nake eyes, the tail fin is roughly about the same size, given the different length of the fuselarge. Question, why B737-500/700 series have such a large tail? Isn't that induces drag? Is there a reason, aside from commonality of parts (which I find that to be difficult to believe), that the tail fin has to be that big? I do see on the 747-SP tail vs regular 747-300/200/100, it is bigger in size, not to mention the SP has a different wing. Please shed some light. Thanks all.