Thinking outloud, the S probably isnt Santa or Silent - Santa is already in the acronym and silent is already in the name - SANTA Silent Knight.
Airborne fits the flying jolly fat man’s profile, as does Night Time.
Assault is Busse lingo and humor.
Stealth
Airborne
Night
Time
Assault
The TA could also be Terror Attack, but that’s just hog bet-hedging.
Stealth
Airborne
Night
Terror
Assault/Attack
Stealth
Airborne
Night
Team
Assault