While NAS523 tells you how to a fastener on a drawing, other guidelines tell you which fastener to choose:
The NW quadrant identifies the (typically referencing standard AN or MS part numbers ) alongside the material composition. Instead of writing out long strings like MS20470AD , a two-letter shorthand code is used.
The outer sheet is dimpled; the thicker subsurface substructure is countersunk. Dimple Two Top Sheets, Countersink Third nas523 pdf top
Hole preparation requirements (e.g., countersinking or dimpling) Lower Right Rivet length (in 1/16" increments) Key Coding Examples Material Codes (NW Quadrant):
Specifies the alloy (e.g., AD for 2117 aluminum) and any required coatings. While NAS523 tells you how to a fastener
If you are a supplier for Boeing, Lockheed Martin, or Airbus, check your supplier portal.
Essential for interpreting Structural Repair Manuals (SRM). Dimple Two Top Sheets, Countersink Third Hole preparation
If you are looking for the top documentation for this device, you should focus on these three specific files:
Here are the key historical revisions you need to know about:
This quadrant is crucial for surface quality and structural fit. It specifies special treatment, such as: Dimpling. D2: Dimple both sheets. D2C: Dimple two top sheets and countersink the third. 4. Southeast (SE) Quadrant: Length