Final answer:
The statement that is not true is C. Search and Rescue missions were successful once implemented.
Step-by-step explanation:
The statement that is not true is C. Search and Rescue missions were successful once implemented.
Search and Rescue missions were important support missions that aimed to rescue people who were in danger or trapped during wartime or other emergencies. While these missions were crucial for enhancing aircrew morale (A) and became important support missions (B), they were not always successful once implemented (C).
For example, during the Vietnam War, the Search and Rescue missions faced challenges due to the guerrilla-style warfare tactics of the Vietcong and North Vietnamese forces. Additionally, in the Battle of Mogadishu, US troops faced significant difficulties during a rescue operation. These examples demonstrate that Search and Rescue missions were not always successful once implemented, making option C incorrect.