Technology Notebook ContentsEffective Date: 15 June 98
Structural loads on the horizontal stabilizer, fuselage, cargo doors, aft ramp, cargo rollers, and teeter rollers are analyzed by plotting the peak drop loads versus parameters such as gross weight, center of gravity, airspeed, altitude, and extraction ratio.
Initial Test
During the initial phase of testing, progression plots are generated so as to be able to predict airplane response and loads as the drop weight is increased. Drop weight and extraction ratio have the greatest influence on airplane response and loads, and hence, are the primary parameters used for progressive plots. The following two sketches Figure 1 and Figure 2. represent typical examples of these types plots where
(Ve, GW, cg, Ext ratio) = constant
and
(Ve, GW, cg, Drop Wt) = constant
Once the primary influence of airspeed and extraction ratio are determined and a reasonable confidence level in the data acheived, testing is expanded to determined the effec of secondary parameters such as gross weight, cg, etc. For example, to determine the effect of cg position, a drop from the weight buildup phase is repeated with all parameters constant except for cg position. The resultant plot is illustrated by the Figure 3 sketch.
Again,
(Ve, GW, cg, Ext ratio) = constant
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