Figure 85 shows a longitudinal cross-sectional view of the cylinder which is the container for the light case and parachute. The main body and fins are of tinned steel (No. 24 gauge), and the lower or firing conical end of brass. In the conical or lower end is soldered a tapped brass bushing to receive the firing mechanism. The flange, shown at the juncture of the nose and main body, acts as a stop to fix the position of the light case in relation to the igniting mechanism.
There are four fins, 1 inch wide by 11 3/4 inches long, spaced equidistant on the outside of the cylinder at the upper end. These have for their function the steadying of the flare when released from the aeroplane, causing the flare to drop in a perpendicular position, thus insuring the action of the igniting mechanism and the proper functioning of the expelling charge. As shown in the figure above, two rings with 1/2 inch grooves are soldered to the outside of the cylinder 7 inches and 30 1/2 inches, respectively, from the firing end. These provide spaces for the suspension bands.
Fig. 85. - Dimensional drawing of shell.
The cap is shown detached from the cylinder at its head or end opposite to the firing mechanism. This cap is bowl shaped of a diameter permitting it to be crimped upon the main shell of the aeroplane flare, which has a diameter of 4 11/32 inches. This cap has a depth of 2 1/4 inches. A tinned steel diaphragm of No. 24 gauge is sweated in midway between the top and bottom of the cap. The function of the diaphragm is merely to form an additional protection for cap-ping the end of the flare. When assembled the cap fits snugly over the top of the shell and closes that end of the container. The cap is held in place by crimping, which is done by hand.
The top suspension band located farthest from the igniting end consists of a coppered-iron band, made to encircle the cylinder, with the ends turned up and punched to receive a brass bolt for tightening around the cylinder, being in effect a "hose clamp." At the opposite side is attached a brass plate holding a spear-head projection for attaching to the release mechanism on the aeroplane.
This band is similar to the top suspension band, except that the brass plate is slotted to allow a lateral movement to the catch permitting adjustment, and the spear-head is formed so as to slide in the slot.
After the flare is completed a paper label 2 by 6 1/4 inches, giving the name of the manufacturer, lot number, date of manufacture and weight, is pasted on the top section of the cylinder between the fins.
The case holds the illuminating composition and is attached to the parachute. The case is made of four sheets two-ply heavy hardware paper. The four sheets having been pasted are rolled together into the form of a cylinder of the dimensions shown in the above figure. This forms a light strong case into which is compressed the illuminating charge. The use of the paper case has the advantage that it burns away with the illuminating charge and thus prevents any chimneying effect and still does not burn so rapidly that the charge is lost.
Fig. 86. - Sectional drawing of light case.
Fig. 87. - Pasting machine.
The general tendency abroad is to substitute metal tubes for the stout heavy paper cases.
A belt-driven pasting machine applies the paste to one side of each sheet.
The operator on the left is seen feeding the paper through the guide which carries it over a roller revolving slowly in a trough of liquid paste. These sheets are similar to those used in rolling the rocket body, two ply, the paste being applied to that side having the smaller sheet. This roller distributes the paste in a uniform manner. The sheets coming off the pasting machine are arranged on the table, with the pasted side uppermost, the first sheet protruding 3 inches beyond the second, the second protruding 3 inches beyond the third, and the third protruding 3 inches beyond the fourth. A set of four sheets thus arranged is laid upon the feed board of the rolling machine.
Fig. 88. - Rolling machine.
The set is laid upon the board with the pasted sides upward and the projecting edges of the undermost sheet forward. In this position the set of four sheets is moved forward until the undermost sheet is inserted in a slot, provided in the mandrel of the rolling machine.