Yes it is possible, and it could even moves in the same hex as Somalis. Here is the sequence
1) Blackhawl fly across board and is subject to one OPfire from small arms and guided anti-aricraft weapon per hex traveled
2) Blackhawk moves adjacent to Somalis and is subject to one OPfire from small arms and guided anti-aricraft weapon
3) Blackhawk can decide to fire right away, provided the Somalis are already spotted (Flying choppers can't spot). It woudl get the +2 for being adjacent but also suffera penalty or being in flying mode
4) It could, instead of firing in Flying mode, shift to hover mode, which offer another OPfire opportunity, this time alowing attack with UNguided ordinance weapon
5) Being in Hovering mode now allows the Blachkawk to spot the Somalis if they were not already spotted and to fire without the penalty for flying chopper
See 13.94.2.1 for rules governing the Delta Sniper teams firing from a Blackhawk