MART Vol. II MO/MP - NESA - Civil Air Patrol

departure and destination. Your true course can be measured with a commonprotractor, or better still with a navigation plotter.When using the GPS, the pilot will be able to easily follow the precise truecourse between departure point and destination. Without the GPS, magneticvariation, wind and compass deviation would affect the aircraft’s ground track.5.9 Tracking and Recording PositionWe have discussed how to use navigational aids and a sectional chart to plotand navigate a course; the same principles are used during flight to keep track ofthe aircraft's current position and to record sightings. VORs, DME and the GPSare excellent tools that allow you to fix your current position. This information, inturn, allows a crewmember to plot that position on a sectional chart.Being able to record and report the position of a ground feature is a criticalskill in all CAP ES missions (e.g., search and rescue, disaster relied andassessment, CD, and homeland security). Once an aircrew locates a downedaircraft or determines the location of a breech in a levy, they must be able topinpoint the location on the sectional and report that position to others. Since thedetails on the sectional chart are often not detailed enough to be useful to groundunits, the scanner or observer usually has to transfer that information to a map(e.g., road or topographical).The state of knowing where you (the aircraft) are at all times is a large part of"maintaining situational awareness" (see Chapter 11 for further discussion onsituational awareness). Navaids allow you to fix your position with great accuracy,and ground features that you can relate to the sectional chart provide confirmationof what your Navaids are telling you about your position. In some situations youmay not be able to receive signals from VORs or NDBs, and the GPS may beyour only useful navaid; if the GPS fails, then recording you position on thesectional chart is your only means of position determination.Knowing the aircraft's position at all times is essential if an in-flight emergencyshould occur. Equipment malfunctions, an electrical fire, or a medical emergencycan necessitate landing at the nearest airport: if you don't know where you are,how can you find the nearest airfield?5.10 Standardized Grid SystemsA grid is a network of regularly spaced horizontal and vertical lines used tohelp quickly locate points on a map. Most city street maps have grid systems thathelp motorists locate streets or other points of interest. A commonly used gridsystem on city street maps involves numerical and alphabetical references.Regularly spaced letters may be printed across the top of such a map designatingimaginary vertical columns, while regularly spaced numbers are printed down thesides of the map designating imaginary horizontal rows. If you want to find MapleStreet and the map directory indicates Maple Street is located in section K-5, youthen look at or near the intersection of column K with row 5. Within that area, youshould find Maple Street.You can construct a grid system on any type of chart or map. You may usenumbers and letters like street maps, or you could use only numbers. In eithercase, the system should give every user a common, standardized method for93