1. Title of the invention
Special Tool for Picking up Holes
2. Field of invention
During an Aircraft upgrade program the Aircraft structure and systems undergo changes. For maintenance and accessing the upgraded systems and LRUs installed in the Aircraft, new doors and access cutouts may be required, While providing doors and covers for these cutouts, holes existing on the fixed structure need to be transferred to the doors, covers and removable panels. This invention is applicable in the field of Prototype Production, Mid Life Upgrade and Major Service Overhaul of Aircrafts,
3. Use of invention
This invention is useful for accurately drilling holes in any removable structure like door, covers and panels during transferring hole locations from the fixed structure of the aircraft to removable structures so that the hole locations match with each other.
4. Prior art
Holes locations were marked in the removable structure by conventional method of measuring hole locations using scale or with some measuring tools from fixed structure and then marking these locations (layout) in the removable structure. Holes were drilled on the removable structure as per the layout plan made.
5. Draw backs of prior art
In the prior art, misalignment of holes between fixed structure of the aircraft
and removable structures were common due to the conventional method of
measuring hole locations on the fixed structure, then marking the matching hole
locations (layout plan) in the removable structure and then drilling holes in the
later part. This resulted in rework and sometimes even rejection of the panels
thus leading to loss of productivity. a-

6. Comparison between prior art and present invention
In the prior art, misalignment of holes between fixed structure of the aircraft and removable structures were common due to the conventional method of measuring hole locations on the fixed structure, then marking the matching hole locations (layout plan) in the removable structure and drilling holes in the later part. This resulted in rework and sometimes even rejection of the panels thus leading to loss of productivity.
In the present method, using the newly invented tools, which are cylindrical shaped with a pointed edge on one side, with the cylindrical portion fitted on to the holes already drilled on the fixed structure and pointed conical portion facing the removable structure. Centre punch mark Impressions are taken on the surface of the removable structure. Holes are drilled on these punch marks as centre reference thus chances of misalignment of holes are eliminated.
7. Aim of the invention
The aim of the invention was to develop a tool and method for accurately transferring holes for drilling from any fixed aircraft structure to removable structure like door, covers and panels so that the hole locations on both structure match with each other.
8. Summary of the present invention
The present invention is a tool and method for accurately transferring holes for drilling from any fixed aircraft structure to a removable structure like doors, covers and panels so that the hole locations on both structure match with each other. In the this method, using the newly invented tools, which are cylindrical shaped with a pointed edge on one side, with the cylindrical portion fitted to the holes already drilled on the fixed structure and pointed conical portion facing the removable structure. Centre punch mark Impressions are taken on the surface of the removable structure. Holes are drilled on these punch marks as centre reference

thus chances of misalignment of holes are eliminated or hole locations on both structures match with each other.
9. Brief description of drawings
FIG.1 is Drawing of Special Tool for picking up holes.
FIG.2 photographs of Special Tools with different diameters for picking up holes.
FIG.3 Special Tool inserted to hole in the fixed structure
FIG. 4 Receiving structure positioned above the fixed structure with Special Tool.
FIG. 5 Centre punch marking (impression) on the receiving structure using
Hammer.
FIG.6 Centre punch marking (impression) used for drilling hole
10. Statement of invention
The invention is the development of a tool and method for accurately transferring holes for drilling from any fixed aircraft structure to it's removable structure like door, covers and panels so that when mated together the hole locations on both structures match with each other (misalignment of holes is eliminated).
li. Detailed description of invention
The invention is a tool and method for accurately transferring holes for drilling from any fixed aircraft structure to a removable structure like doors, covers and panels so that the hole locations on both structure match with each other.
The invented tool is can be made from high carbon steel and fabricated by conventional machines. In this method, using the newly invented tools, which are cylindrical shaped with a pointed edge on one side, with the cylindrical portion fitted to the holes already drilled on the fixed structure and pointed edge facing the removable structure. Centre punch mark Impressions are taken on the surface of