Lindbergh believed that a flight made in a single-seat monoplane designed around the dependable Wright J-5 Whirlwind radial engine provided the best chance of success. The Ryan NYP had a total fuel capacity of 450 U.S. gallons (1,700 L; 370 imp gal) or 2,710 pounds (1,230 kg) of gasoline, which was necessary in order to have the range to make the anticipated flight non-stop. The fuel was stored in five fuel tanks, a forward tank – 88 U.S. gal (330 L; 73 imp gal), the main – 209 U.S. gal (790 L; 174 imp gal), and three wing tanks – total of 153 U.S. gal (580 L; 127 imp gal).[5] Lindbergh modified the design of the plane's "trombone struts" attached to the landing gear to provide a wider wheelbase in order to accommodate the weight of the fuel.[6]