Secondly, I am not sure I understand the question. You mean why are the inboard flaps not connected to the fuselage? If that is your question, HAWK21M is correct that some of them are. But I don't know the particulars of flap design well enough to tell you why or why not.
"There are no stupid questions, but there are a lot of inquisitive idiots." - from Citadel by John Ringo
Molykote From United States of America, joined Aug 2005, 1337 posts, RR: 30 Reply 3, posted (6 years 8 months 1 week 6 days 10 hours ago) and read 1984 times:
I'm not sure about the exact nature of your question either....
However, if you are asking why the flaps have a "gap" in continuity at the spanwise engine location consider the effect of the violent exhaust stream on the flap structure and potential alterations to aircraft handling.
Jetlagged From United Kingdom, joined Jan 2005, 2505 posts, RR: 24 Reply 4, posted (6 years 8 months 1 week 6 days 7 hours ago) and read 1911 times:
From the thread title I assume the question is about the split between the inboard and outboard flaps. In all three examples shown, the inboard and outboard flaps have inboard ailerons between them (OK on the 777 they are called flaperons ). The split at the engine is convenient but not essential. Other aircraft have continuous flaps across the engine exhaust, often for beneficial reasons.