Half Cell Chordwise Construction Lower surface panels Loaded ribs Typical Non-loaded ribs Upper surface panels Section view from front Full Cell Chordwise Construction “I” Beam Lower surface panels Loaded ribs Typical Typical Typical Typical Non-loaded ribs Upper surface panels Section view from front Full Cell Construction Interlocking “T” Beam Lower surface panels Loaded ribs Typical Typical Typical Typical Non-loaded ribs Upper surface panels$^{Section view from front}$ Spanwise Construction Lower surface panels Loaded ribs Typical Typical Non-loaded ribs Upper surface panels Section view from front Figure 4D. Figure 4C.  Figure 4B. Figure 4A.  Change 1 (December 2015)  A-14