Earlier helicopters had demonstrated the idea, but the S-55 family combined useful payload with enough reliability and efficiency for sustained operations. It still required considerable maintenance and was harder to fly than later types. Even so, operators could assign it real missions with a reasonable expectation that the aircraft would complete them. The family ran to nearly 2,100 aircraft, evidence of how widely that balance of difficulty and capability was accepted.
Chapter · 0:00-2:18
The helicopter comes of age
The S-55, H-19 Chickasaw, and Westland Whirlwind reach the point where helicopters are reliable and useful enough for sustained operational work.