Rin

[helicopter2009]

can anyone explain about retirement index number and method of determination of it for a new main rotor mast ?

[Ancient Rotorhead]

A posting in Rotorheads would probably produce a reasoned answer. However, ask the instructor who endorsed you on the 206L or whatever.....:rolleyes:

[helicopter2009]

Is there any public released papers that can help about retirement index number?

[mendi63]

Look here:

http://www.bellcustomer.com/files/Storage/IL%20GEN-03-94%20.pdf

[helicopter2009]

I have studied this paper and some other texts like this. But I want to know if there is any relation between retirement index number and damage rules like miner's rule and how retirement index number is assigned for a component.
thanks anyway
[email protected] ([email protected])

[Driptray]

RIN is a Bell terminology, and each aircraft type has components which are lifed based on either hours or RIN cycles. A mast may have a life of perhaps 5000 hours or x amount of RINs, this is a fatigue cycle calculation, and the formula is provided in the relevant aircraft models ASB's and Information Letters and the Chapter 4 of the relevant Maintenance Manual. The component (In this case the mast) could, depending on the nature of your flying be due for retirement prior to the hour figure being reached, if you are heavily involved in external load lifting for example. Bell assign this limit, and it is the responsibility of the pilot to accuratly record torque events, landings, hoist cycles etc, which are stipulated by the manufacturer. Your maintenance facility should be able to explain this specifically for the aircraft type you are flying, as it is they who should apply the formula to your aircraft, and they should advise you if you are approaching a retirement limit, either hour or RIN based.

[helicopter2009]

thanks
I studied several ASB's and Information Letters related to bell 214 but I cant't find the fatigue cycle calculation formula for determining amount of RINs for the mast. And I can't access bell 214 Maintenance Manual. I checked bell web site and there is'nt any online version.Could you please send the formula or the Maintenance Manual and explain more?
[email protected]

[Driptray]

Talk to Bell Tech Reps, they will be able to tell you exactly what you require or failing that try McDermott Aviation, they are the 214 Operators in Oz and should have up to date info, however, 214B mast is Hours only according to info I have, and the 214ST is RIN lifed.

Do not use this as gospel, my info is from an out of date manual and may not be accurate.
See below.

214B 214-040-090-105, -117 Main Rotor Mast Assembly 5000 hours



214ST Main Rotor Mast 214-040-090-109 140000 RIN notes 1 & 2
note 1 RIN (Retirement Index Number) is the retirement life based on fatigue damage from
normal helicopter lifts and takeoffs. New components will begin with an accumulated RIN
of zero that will be increased as lifts and takeoffs are performed. Operators must record
the number of lifts and takeoffs and increase the accumulated RIN accordingly. When the
maximum RIN or retirement flight hours is reached, whichever occurs first, the component
will be removed from service.
Note 2 Each takeoff or lift counts as 2 RIN. If logging, increase RIN count to 4.