I worked for Bell Helicopter International in Iran from 1974 to 1977. It was during that time that I became aware of the mast bumping and resultant rotor loss. The last Bell helicopters that I had anything to do with prior to that time never had the problem because the rotors were restricted in their flapping by Sprague Cables. The reciprocating engines were also restricted in their movement by the same type of cables.
It wasn't until the advent of the 206 that the problem of mast bumping started and continued with the 205. I am not aware of mast bumping occuring on any follow on models. I first became aware of mast bumping
0n the Robinson when I visited Geneva Aviation in Everett,Washington. Geneva specializes in A Star and Twin Star helicopters but they were pulling maintenance on R22s that were owned by the president of Geneva. The lead mechanic told me about the problem and I also saw some unusual wear on a R22 rotor head. Being of an Inquisitive nature I started my investigation. That was around 1990-91.
Prior to publishing my report, I contacted Robinson Helicopters to tell them of my findings. I sent two faxes with no reply. I phoned Robinson and talked to Kurt Robinson, Franks son. he informed me that they weren't interested. It was then that I decided to send the report to the NTSB.
Regarding you not having the referenced page in your POH then the CAA has a major problem.
Regarding the pages in section 4 (Normal Procedures) they are (at least in my copy);
4.1,4.1 (page number repeated but with different info), 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9, 4.10, 4.10.1, 4.10.2, 4.11
and the last page is un numbered. This page is titled normal procedures section NOTE. This page addresses Main Rotor Stall and mast Bumping and has a section that sets up the restrictions to avoid these conditions and one of the notes reads; Avoid sideslip during flight. Maintain in-trim flight at all times. At the bottom of the page it states: Issued Per FAA Priority Letter AD Dated: 13 Jan 95. I think you should talk to your Robinson dealer and ask why this page is not in you POH. This same page is in my copy of the R44 POH
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The Cat