"C" Check and "Phase-in" check B737

[Mariner9]

I'd be grateful if someone could explain in layman's terms what the above checks would entail, and how often they would typically be undertaken. (Im not looking for any degree of detail, just a broad overview please).

Thanks in advance :ok:

M9

[Tinwacker]

PHASED “A” CHECK (B744 Passenger Aircraft) as an example.
The B744 Phased "A" check (PA-1, to PA-4) is a grouping of "A" up to "4A" check tasks distributed evenly to be done at every 1000 FH/220FC/60 Days whichever is earlier.
In the event when deferral of a task becomes inevitable, variation may be applied for, and granted, up to the limit authorized by the CAD. In any event, the maximum variation allowable shall be calculated based on the assumption that the interval of the task is 1000 FH/220FC/60 Days, regardless of the actual interval approved in the AMS for that task.
All tasks incorporated in all Phased “A” checks (A2/A2/A3/A4) will be clocked zero during "C" check maintenance input.

“C” Check
A check requiring maximum access opening and including maintenance significant items which require periodic inspections for condition and security of installation, lubrication and Operation or Functional Checks.
Performance of the "C" Check needs not to be in conjunction with “4A” Check and lesser checks.
“C” Check is to be carried out at an interval not exceeding 10000 FH or 24 Months, whichever occur first, for passenger and freighter aircraft since previous “C” Check..
A Final Certificate of Release to Service is to be issued after each “C” Check.

The "PHASE" check and "C" check can be broken into segments to better utilise the aircraft and hangar/staff availability.

TW

[Mariner9]

That's great Tinwacker, exactly what I needed. Many thanks :ok: