Which of the following is NOT a pilot requirement before a flight?

Conducting passenger briefings, while an important aspect of ensuring passenger safety and awareness during a flight, is not classified as a pilot requirement that directly affects flight operations. The other options represent critical pre-flight checks that pilots must perform as part of their responsibilities.

Checking the weather is essential for pilots to understand current and forecasted conditions, which might influence flight plans and safety. Similarly, checking NOTAMs (Notices to Airmen) is vital for pilots to be informed of any temporary changes to flight operations, such as runway closures or airspace restrictions. Verifying weights and balances is also critical, as it ensures that the aircraft is loaded properly, which is crucial for the safety and performance of the flight.

In contrast, while passenger briefings enhance communication and safety, they do not fall under the regulatory requirements that pilots must meet before taking off. This distinction is important in understanding the broader context of pilot responsibilities.