Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_45353 ( "Rank" text, "Badge/Serial Number" text, "Tenure" text, "Date of death" text, "Cause of death" text )

### Question ###
What is the Tenure of the Officer who died in a helicopter accident with Badge/Serial Number 16805?

### Accurate SQL ###

SELECT "Tenure" FROM table_45353 WHERE "Cause of death" = 'helicopter accident' AND "Badge/Serial Number" = '16805'