The most common and most likely answer to this crossword clue is the 6 letter word BURTON
B
U
R
T
O
N
More clues leading to the result BURTON
Buddy explains!

The straight part
We know that "Tackle" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case tackle = burton.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 BURTON mean?
BURTON noun- An arrangement of blocks and pulleys, especially for tightening rigging on a ship.
- Storage of cargo athwartships.