DATCOM_XL is a collaction VBA functions enabling a fast & easy to capability + a transparent & reproducable estimation of (aircraft) aerodynamic (stability and control) derivatives. DATCOM_XL is based on the source literature - also available in the repository - the USAF Data and Control Compendium as well as a number of NACA papers, an international standard atmosphere calculator and useful imperial to mertic conversions. You may use DATCOM_XL advantages given by Excel and by the predefined spreadsheet. Enabling the user to visualise inputs. The present version is limited to a number of qquations, figures and tables . In case of any question to the extended version of DATCOM_XL, called DATCOm_XL+ or any other inquiries feel free to contact: s.deubler@ymail.com Have Fun, Sabby