Educate me. I know the other parts. What is a drag beam? So, they experience stress. Can they not be replaced? The transmission support beam is relatively small. Point is, most helo cabin structure don't wear out. Monocoque airplane fuselage get bent or overly stressed you get an Aloha convertible, or worse.
Many of the Army Hawks didn't have near the number of hours on them that the Navy birds did. In mid-2000's, I ran into some Guard guys and they're 1979 A-models had 5K on them. Ours had 9K and 10K. When the community retired the Bravo, many had 12K+ on them, so it showed a lot of the potential wear that can happen.
The drag beam is the beam that supports the main landing gear at the stub wing. There's immense pressure there because of how the landing gear sits. There is increased wear on the Navy aircraft (specifically the small boy helos) because of post-flight movement on the flight deck to put it in the hangar, but it's still wear.
Typically at least one aircraft (out of 2) coming back from deployment would require a drag beam P&E.
The overhead beam wasn't quite as typical a repair, but still semi-regular. Again, it required a P&E. I honestly can't completely remember what the cause was, but I think it was harder landings.
Do these issues equal the same use on the civilian side? Hour for hour, probably not, but I compare it to a rental car. A personally owned car is usually in better shape than a rental car with the same mileage because of the hard use of the rental car. But the rental car is a good gauge of what issues the car may have down the line with use.
BL, they're great airframes, but to say they'll last indefinitely is a loaded statement. Artisans can do amazing work, but that's why I said it's the data plate that can last indefinitely.
