The number of aircraft anticipated to be built is most likely to be protected by the Non-Disclosure Agreement (NDA). This information is sensitive as it can reveal the scale of the project, future business plans, and production capabilities, which competitors could exploit if they gained access. The NDA ensures that the supplier keeps this information confidential to protect the interests of the aircraft manufacturer. Other details like the time frame, start date, and the name of the end customer are also important but the quantity of aircraft directly ties to the company's strategic plans and capacity. References:

•Bagley, C. E., & Dauchy, C. E. (2018). The Entrepreneur's Guide to Law and Strategy. Cengage Learning.

•Seidel, G. (2014). Negotiating Business Transactions: An Extended Simulation Course. Aspen Publishers.