Aircraft Sheet Metal Numbering System

The final two digits the sequence numbers are numbers that simply place the sheets in order.

Aircraft sheet metal numbering system.

Some sheet metal aircraft utilize construction techniques that use nothing but pop rivets that are pulled using a small inexpensive rivet tool. Aluminum lithium alloys were developed for reducing weight in aircraft and aerospace structures. The upper number in each cell is the bend allowance for a 90 bend. Once drilled use a pin punch to tip off the rivet head and drive the remaining shank out of the hole while supporting the surrounding metal.

Center punch the rivet then drill just to the base of the rivet head with the same size or one size smaller drill. To locate structures to the right or left of the center line of an aircraft a similar method is employed. The terms are used in sheet metal forming and flat pattern layout. The tools required for this type aircraft are minimal.

Many manufacturers consider the center line of the aircraft to be a zero station. How bend calculations are used in a bending operation. Efficient operation of any aircraft is greatly dependent upon correct selection and use of aircraft structural hardware and seals. Aircraft technician relies on a wide variety of powered and hand operated tools to precisely bend and fold sheet metal to achieve the perfect shape.

The lower number in the cell is the bend allowance per 1 of bend. Department of transportation federal aviation administration 800 independence avenue sw washington dc 20591 866 tell faa 866 835 5322. Flange is the shorter part of a formed angle. Base measurement is the outside dimensions of a formed part.

Aircraft hardware is discussed in detail in the structural hardware manual navair 01 1a 8. Natural grain of the material is formed as the sheet is rolled from molten ingot. The third digit the sheet type is a number that represents the type of drawings that are on the sheet plans sections details schedules etc. Other aircraft kits use regular structural rivets that must be squeezed or driven.

To determine the bend allowance for a 90 bend simply use the top number in the chart. Various numbering systems are used to facilitate the location of specific wing frames fuselage bulkheads or any other structural members on an aircraft. Manufacturers use some system of station marking. Forming sheet metal requires a variety of tools and equipment both powered and manual.

Bend allowance and bend radius all the space between the band tangent lines is the. Types of shrinking and stretching tools used for aircraft metal structural repair. Forming at room temperature is known as cold forming. Any bend formed on a.