Preface to the 2026 Edition

The continued growth in eBook use in 2025 reflects its increasing adoption by students and instructors worldwide, with access statistics for the year showing 517,584 unique visitors, a 45% increase over 2024, and more than 860,000 unique page views, up 29%. This sustained engagement has shaped the 2026 edition, which incorporates another substantial round of updates and enhancements informed by classroom use and reader feedback. The eBook has expanded significantly over the past several semesters and now supports instruction in the third and fourth years of an undergraduate curriculum. Several chapters also include material appropriate for graduate-level courses.

The 2026 release features numerous new and revised figures, along with additional worked examples and fully solved problems in each chapter, intended to strengthen conceptual understanding and problem-solving skills. Many chapters have also been reorganized to improve clarity and instructional flow for both students and instructors. New chapters in the 2026 edition address core revision physics for engineers, thermodynamics, airplane propellers, wind tunnel testing, and vertical takeoff and landing (VTOL) aircraft.

Suggestions for additions and improvements are always welcome.

J. Gordon Leishman
Distinguished Professor of Aerospace Engineering, ERAU, Daytona Beach, FL.
Professor Emeritus of Aerospace Engineering, University of Maryland, College Park, MD.

Contact the author via email at FlightVehicles.eBook@gmail.com.