LIGHTSteady green light gun (in flight)?
Cleared to land (on ground = cleared for takeoff).
LIGHTFlashing red light gun (in flight)?
Airport unsafe, do not land (on ground = taxi clear of runway).
INCURPrevent runway/heliport incursion?
Verbatim readback of hold-short/crossing; keep a current diagram in view; self-announce clearly.
HELIHeliport touchdown marking?
An ‘H’ with touchdown/positioning circles; check size/weight markings in the Chart Supplement.
PATTHelicopter pattern vs airplane?
Lower & tighter, often to a spot, frequently opposite/offset from the airplane flow.
WAKEAvoid wake turbulence?
Stay above and upwind of the heavier aircraft’s flight path.
AVOIDPrimary collision avoidance VFR?
See-and-avoid, supported by clear radio calls and good sequencing.