Aircraft Velocity Never Exceed Speed (V$_{NE}$)/(Miles Per Hour) Maximum Spacing of Rib Lacing (Inches) 100 150 200 250 300 4 3 2 1 Spacing other than in slipstream (non-prop wash area) Spacing in slipstream (prop wash area) Tape Half hitch Rib cap Fabric Square knot square knot with a half hitch on each side is typically used  for the first knot when lacing a rib.  [Figure 3-26]  This is  followed by a series of modified seine knots until the final  knot is made and secured with a half hitch.  [Figure 3-27] Hidden modified seine knots are also used. These knots are  placed below the fabric surface so only a single strand of  lacing is visible across the rib cap.  [Figure 3-28]  Structure and accessories within the wing may prevent a  continuous lacing. Ending the lacing and beginning again  can avoid these obstacles. Lacing that is not long enough to  complete the rib may be ended and a new starting knot can  be initiated at the next set of holes. The lacing can also be  extended by joining it with another piece of lacing using the  splice knot shown in  Figure 3-29 . Figure 3-26.  A starter knot for rib lacing can be a square knot with  a half hitch on each side. Figure 3-25.  A rib lacing spacing chart. Unless manufacturer data specifies otherwise, use the spacing indicated.  3-19