G S HDG NA V 33 30 24 2I I5 I2 6 3 Heading select bug Compass warning flag Heading select knob NAV warning flag Lubber line Course deviation bar (CDI) Course deviation scale Course select pointer Compass card Symbolic aircraft Glideslope pointer Course select knob XPDR 5537 IDNT LCL10:12:34  INSET  PFD  CDI  XPDR  IDENT  TMR/REF  NRST  ALERTS  VOR 1  270 °  CRS 270° HDG 270°  2  1  1  2  5 00  5300  5200  5100  5000  4900  4800  4300  3600  3500  3400  3300  3200  3100  20 80 5040 5000  130  120 110 90  80  70  1 100 9 TAS 106KT  OAT 6°C  NAV1 108.00 113.00 NAV2 108.00 110.60 134.000 118.000 COM1 123.800 118.000 COM2 $_{WPT }$_ _ _ _ _ _$_{ DIS }$_ _ ._ $_{NM}$ $_{DTK }$_ _ _$_{°}$ TRK 270° Heading Heading select bug Lubber line Course select pointer Course deviation scale Course deviation indicator (CDI) Compass card Selected heading box Figure 9-13. A typical horizontal situation indicator (HSI). Figure 9-14. An HSI display as seen on the pilot’s primary flight display (PFD) on an electronic flight instrument. Note that only attributes  related to the HSI are labeled. 9-12