slack is about to occur and correct accordingly. The vertical  position should be the normal high tow. Any tow position  that is lower than normal runs the risk of the slack line  coming back over the glider. On the other hand, care should  be taken to tow absolutely no higher than normal to avoid  a forced release should the towplane suddenly drop. Gusts  may also cause an excessive bank of the glider, and it may  take a moment to roll back to level. Full aileron and rudder  deflection, held for a few seconds, is sometimes needed. Towing into the wave can be accomplished by either towing  ahead of the rotor or through the rotor. Complete avoidance  of the rotor generally increases the tow pilot’s willingness to  perform future wave tows. If possible, tow around the rotor  and then directly into the wave lift. This may be feasible if the  soaring site is located near one end of the wave-producing ridge  or mountain range. A detour around the rotor may require more  time on tow, but it is well worth the diversion.  [Figure 10-33] Often, a detour around the rotor is not possible and a tow  directly through the rotor is the only route to the wave. The  rotor turbulence is, on rare occasion, only light. However,  moderate to severe turbulence is usually encountered. The  nature of rotor turbulence differs from turbulent thermal  days, with sharp, chaotic horizontal and vertical gusts along  with rapid accelerations and decelerations. At times, the rotor  can become so rough that even experienced pilots may elect  to remain on the ground. Any pilot inexperienced in flying  through rotors should obtain instruction before attempting  a tow through rotor. Progress through the rotor is often indicated by noting the  trend of the variometer. General downswings are replaced by  general upswings, usually along with increasing turbulence.  The penetration into the smooth wave lift can be quick—in a  matter of few seconds—while at other times it can be more  gradual. Note any lenticulars above; a position upwind of  the clouds helps confirm contact with the wave. If in doubt,  tow a few moments longer to be sure. Once confident about  having contacted the wave lift, make the release. If heading  into more or less crosswind, the glider should release and fly  straight or with a crab angle. If flying directly into the wind,  the glider should turn a few degrees to establish a crosswind  crab angle. The goal is to avoid drifting downwind and  immediately losing the wave. After release, the towplane  should descend and/or turn away to separate from the glider.  Possible nonstandard procedures need to be briefed with the  tow pilot before takeoff.  [Figures 10-34  and  10-35] When towing through a rotor, being out of position is  normal. Glider pilots must maintain position horizontally and  vertically as best they can. Pilots should also be aware that an  immediate release may be necessary at any time if turbulence  becomes too violent. Slack-producing situations are common,  due to a rapid deceleration of the towplane. The glider pilot  must react quickly to slack if it occurs and recognize that  Wind Slope lift Wave sink Wave lift Rotor cloud Wave sink Ridge crest Figure 10-33.  If possible, tow around the rotor directly into the wave. 10-19