Curtis NC-4 six-seat four-method long-range water patrol aircraft is produced by Curtis Company of the United States. 19 17 years, the submarine war was a great success. Curtis's NC-4 plane came from the US Navy to deal with this threat, and later became famous for successfully crossing the Atlantic Ocean. At that time, the new plane was required to have the ability to fly across the Atlantic alone, because no ship could accommodate its huge volume and transport it from the United States to Britain. This means that the aircraft should have a endurance of 15 to 20 hours, adopt a variety of designs, and be strong enough to complete the forced landing at sea. Curtis was the only manufacturer with experience in manufacturing this kind of aircraft at that time, but the 2800-pound biplane fuselage it made was designed by the US Navy. The number NC comes from the initials "Navy" and "Curtis". The first NC-4 completed its first flight in 19 18 10, but it was too late to participate in World War I. Three NC planes made a test flight across the Atlantic in May 19 19, but only NC-4 arrived in the UK. After the war, Curtis Company produced six more NC planes, which remained in service until the 1920s.