The most common and most likely answer to this crossword clue is the 7 letter word AIRDROP
I've seen this crossword clue in The Times
A
I
R
D
R
O
P
More clues leading to the result AIRDROP
- Heaven-sent supply of gas medic opens, perhaps, at the front
- Helter-skelter or rapid delivery by chute
- Delivery that is dispatched from Scottish town before work
- Broadcast to omit sudden lowering of food supplies
- Charity work from Sky using 16 perhaps?
- 13 Delivery made by down-to-earth supplier
- Sort of rapid or overhead delivery?
- Special delivery offered by ace Irish doctor before work
- Broadcast operation after doctor gets supplies sent down
- Aid work interrupted by rains, ruined basically a delivery for the affected
Buddy explains!

The straight part
We know that "Heaven-sent supply" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case heaven-sent supply = airdrop.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does AIRDROP mean?
AIRDROP noun- The act of delivering goods, equipment, or personnel by dropping them from an aircraft in flight.
- To delivery goods, equipment, or personnel by dropping them from an aircraft in flight.