<div class="htmlview paragraph">An improved high-strength, high-toughness steel has been developed which shows considerable promise for landing gear applications. Previous materials provided high strength or high toughness, but not both. The improved material is a modified chemistry of AF1410 steel with increased carbon and an altered heat treat process. Tensile ultimate strengths (F_tu) of over 260 ksi (1.79 GPa) have been achieved while maintaining plane strain fracture toughness (K_lc) in excess of 100 ksh/inch (110 MPa√m). In addition, the material has low sensitivity to environmental factors such as hydrogen embrittlement and stress corrosion cracking.</div>