For military helicopters such as the Sikorsky UH-60 Black Hawk, what is the typical fatigue life of a helicopter airframe (in cycles and hours) ?

  • $\begingroup$ You may want to break this into a few questions (this stack normally only answers one question at a time per, well, question.) The first Q is probably fine on it's own, the second... You'll probably need to be mores specific than "any dynamic part" since they all will have different life spans... $\endgroup$ – Jay Carr Jul 18 '15 at 3:13
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    $\begingroup$ Hi Jay, thanks for your suggestions. I welcome answers to both questions herein and I will also create another "question" on its own for question 2. $\endgroup$ – Raptor Jul 18 '15 at 3:18

Typical helicopters do not have cycles or hours limits on the non-dynamic components.

Since they are not pressurised, there is no concept of "cycles" and the fuselage is neither stressed, nor subject to the same kinds of forces that airliners are.

They are inspected on fixed hours cycles and specific types might have areas which are subject to non-destructive testing in accordance with operator, manufacturer or regulatory instructions. Some, most notably Robinsons, are rebuilt by the manufacturer on hours based cycles and return as new. However, the fuselage and it's major components are not replaced. They are inspected and refurbished.

The dynamic components are of course lifed but I see that you have a separate question for that.

  • $\begingroup$ Hi Simon, thanks for your inputs. To my understanding, the airframe of a helicopter (or aircraft) usually has a design life which is indicated in hours. So it would be helpful to know this number in hours or cycles for specifically military helicopters such as the Black Hawk? $\endgroup$ – Raptor Jul 19 '15 at 4:27
  • $\begingroup$ @Raptor I don't know anything about the UH-60 but no helicopter I am familiar with has a fatigue life, including military. $\endgroup$ – Simon Jul 19 '15 at 13:28

The Robinson R-22 and R-44 helicopters are life limited to 2,200 hours or 12 years:

The complete airframe, including rotor systems, drive system, control system, and fuselage, must be overhauled as instructed by Robinson Helicopter Company when any of the following occur: 1. When the helicopter has been operated for 2200 hours since new or since last overhaul

  • $\begingroup$ Hi rdp, thanks for your inputs. However, it would be helpful to know: What sort of airframe fatigue life is expected for military helicopters such as the Black Hawk for instance? That is the specific question I would like to ask. Thank you. $\endgroup$ – Raptor Jul 19 '15 at 4:18
  • $\begingroup$ This is true, but it's not a fatigue life. The fuselage, frames etc and inspected, repaired if needed, and refurbished. They are not replaced unless needed, and are not lifed. $\endgroup$ – Simon Jul 19 '15 at 13:28

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