the airspeed and surface wind limitations. Safe operation in  controlled airspace requires that the controller understand  the performance and limits of the WSC aircraft. Knowledge of airspace dimensions, requirements to enter  the airspace, and geographical location of the airspace is  the responsibility of all pilots. The current sectional chart  is the primary official tool to determine the airspace fl ying  within or avoiding. Pilotage is navigation by reference to landmarks to determine  location and the location of airspace. Pilotage is the best form  of navigation to ensure that you avoid airspace not authorized  to enter. Locating your position on the sectional chart and  locating/identifying the airspace you want to enter/avoid  requires preflight planning on the ground and situational  awareness in the air. For all flights, pilots must be sure to have enough fuel to  complete the flight. For longer cross-country fl ights, this  requires the pilot to check winds aloft and calculate the  groundspeed for the planned altitude and forecast wind. The  resultant time to the destination and the fuel consumption  determines the fuel required to make the flight. This prefl ight  planning is especially important for slower WSC aircraft  because increased headwind components provide signifi cant  time increases to get to fuel stops than faster aircraft.  Although 14 CFR section 91.151 requires airplanes to have  at least 30 minutes of reserve fuel for an intended fuel stop;  this minimum is also recommended for WSC aircraft. The  Pilot’s Handbook of Aeronautical Knowledge chapter on  navigation provides procedures in navigation, plotting a  course, determining groundspeed for the predicted wind,  headings and the required fuel for intended legs of the fl ight.  For any cross-country flight, a flight log should be used and  the planned groundspeed should be compared to the actual  GPS groundspeed measured in flight. If the GPS groundspeed  is lower than the planned groundspeed, the time en route and  the fuel reserves must be evaluated to assure the WSC aircraft  does not run out of fuel during the fl ight. GPS is a very popular form of navigation used by WSC pilots.  The GPS receiver is small, simple to use, and inexpensive  compared to other forms of electronic (radio) navigation.  Simple modes of operation provide actual groundspeed and  time to a waypoint. More sophisticated GPSs have aviation  databases and provide the pilot a considerable amount of  information about airports and airspace. When using GPS  to determine airspace or airport position, boundaries, and/ or information, the aviation database in the GPS may not  exactly match the information as depicted on the sectional  chart. If there is a difference between the sectional chart and  GPS information, the sectional chart should be considered  correct. A WSC pilot using GPS should ensure that the batteries  are fresh and the aviation database is current. Never rely on  the GPS as a primary navigation system. Pilotage using the  sectional chart is the primary navigation system when fl ying  beyond visual range of a familiar airport. The GPS is used  only as a backup aid for navigation. With proper preflight planning and constant evaluation of  the planned verses actual flight performance, cross-country  flight is practical in the NAS for WSC pilots. At first glance, the NAS appears to be a complex arena  in which to operate such a simple aircraft. This chapter  simplifies the airspace for the reader, and makes it readily  apparent that it is possible to operate a WSC aircraft safely,  without causing confl ict. Simple courtesy and common sense go a long way in airspace  operations. A complete and thorough understanding of the  airspace, combined with good decision-making, will allow  the pilot to do what he or she wishes, with recognition of the  needs of other users of the sky.  Chapter Summary  Navigating the Airspace 8-13