L-15 Scout: Boeing’s Smallest Airplane

As World War II drew to a close, Boeing, realizing that its huge Wichita factory would be out of work at war’s end, began working on a light personal airplane. It nabbed the contract for what became the L-15 Scout despite the plane’s third-place finish in a 1946 U.S. military liaison aircraft competition. Although the aircraft ultimately was not mass produced, Boeing’s engineers created proposals for both military and civilian follow-ups. This book tells for the first time the full story of the L-15—the competition and the competitors, the evolution of Boeing’s entry into the prototype XL-15, the plane’s specifications, the rivalry between the U.S. Army and Air Force, and the government’s decision to adopt a different plane instead.

Mal Holcomb is retired from a 45-year engineering career in the general aviation industry specializing in aerodynamics, aircraft design, and flight testing and has written many technical papers as well as historical journal and magazine articles. He lives in Mountain Home, Arkansas.

Preface 1

Introduction 3

Abbreviations 5

 1. Post–World War II Outlook for Personal Aviation 7

 2. Boeing Looks at a Light Personal Airplane 16

 3. ­XL-15 Liaison Aircraft Competition 29

 4. Boeing’s Winning Entry 54

 5. ­XL-15 Testing and Design Refinement 64

 6. Performance 93

 7. Airframe 106

 8. Propulsion 126

 9. Landing Gear 138

10. Systems 146

11. Weights 175

12. Ground Handling and Maintenance 183

13. Boeing Pilot Comments on the ­YL-15 194

14. USAF ­YL-15 Accelerated Service Test 209

15. The Army, the Air Force, and the ­L-15 217

16. Boeing’s Projected Follow-on ­L-15 Versions 231

Appendix: ­L-15 Design Patent 237

Chapter Notes 241

Bibliography 249

Index 253