You Do Need power plug adapter while traveling from Sint Maarten to Chad.

Here is Why You Need An Adapter

The outlet and plug type used in Chad are C, D, E and F and in Sint Maarten are A and B. This is how they look like.

Sint Maarten

In Sint Maarten, outlets of type A and B are in use.

Type A

Type B

Chad

In Chad, outlets of type C, D, E and F are in use.

Type C

Type D

Type E

Type F