What does the cryptic crossword clue "They fly nighttime weapon aboard planes (4-5)" mean?

The wordplay uses a container (one word inside another). DART (synonym="weapon") in SANDS (synonym="planes") = SANDDARTS The answer is SANDDARTS.

They fly nighttime weapon aboard planes (4-5)

Guardian Cryptic #29527 | 2 Down | 2024-10-30 flower