When an item is considered to be a Life Limited Part it means that the item has a limit which forms a part of the initial design.
Once the life limit is reached then the item is no longer considered to be serviceable and as such will require removal form the aircraft.
Some items can have multiple limits applicable to them such as some engine components; and others such as a part of a landing gear may only have one limit.
Maintenance Reserves are monthly payments made by the airline to the lessor. The payments are often referred to as “Supplemental Rent” and belong to the lessor. The accumulation of the funds is used to cover the costs of scheduled major maintenance events on Airframe, Landing Gear, Engines and APU. The table in our illustration gives an idea of typical MRF rates for a B737NG with CFM 56 engines installed.
The AMP is a specific maintenance plan for any particular aircraft. When the document is created there are many different sources for us to consider.
We have mentioned in prior post’s about how certain MPD (Maintenance Planning Data) thresholds / intervals can be changed in an AMP depending on factors such as environment, regulatory body, reliability etc.
There are also multiple additional sources for the AMP that are important considerations while the MPD forms a core section of the AMP. What we need to consider is further ICA’s (Instructions for Continued Airworthiness) that might apply for our aircraft.
For example, over time the aircraft may get damaged and as such have repairs; the repair in turn will have an ICA associated which may impact your aircraft; additionally, AD’s (Airworthiness Directives) where repeat inspections apply could also form a part of the AMP.
One of the major growth areas in aviation over the last 12 months is the “parts” or “spares” industry with increasing numbers of assets going for tear down. We have had a number of requests from followers to discuss at a high level COMPONENTS on an aircraft.
Components can be considered in two basic categories:
OCCM – On Condition / Condition Monitored Components
HT – Hard Time Components
A component which is “HT” or “Hard Time” simply means the component has a defined life. It will be usually counted in Aircraft Hours or Aircraft Cycles (although may be calendar days). The limit will normally be defined by a manufacturer (OEM) and at this limit a defined action will be required such as overhaul or bench testing. This requirement is not affected by the components function or standard and is required regardless of condition.
An aircraft lease can be a complex event when dealing with the multiple tasks and considerations regarding the return conditions as defined in a lease agreement.
The task’s associated with reviewing those conditions against the aircraft and its associated records protect the value of the asset and also ensure a known standard for the next transition.
Depending on your role in a transition you might well find that you will be involved also in a “bridging check”.
An aircraft can only operate under one Aircraft Maintenance Plan(AMP); so typically, different operators, or even a lessor receiving an aircraft will have different requirements to the AMP which is currently in use.