The Traffic Factor 1

It is of the utmost importance to always be conscious of other aircraft in your vicinity throughout your training and future flying in a twin.  The engine nacelles present the pilot with a tremendous increase in the amount of blind spots that you must have to contend with.  A second factor is your speed.  It is very easy to overtake another aircraft, especially in the vicinity of airports; always be extra conscious of traffic that could move into the arch that lies between your nine o’clock and three o’clock position.  Here are some habits that you should be developing:

  • Don’t fly on a straight course in the vicinity of airports or in a training area for long unless it is operationally required; during training there is rarely a requirement to maintain a constant heading for a prolonged time, so get in the habit of regularly changing course.
  • If you have to fly a straight course, periodically drop a nacelle using a gentle roll to keep blind spots clear.
  • Prior to making a turn, say “clear right” or “clear left” so that your instructor knows you have visually cleared the airspace for traffic.
  • Reduce speed when in the vicinity of an airport where the airspace could be thick with other aircraft, including aircraft with student pilots.
  • During a climb or descent, be sure to make periodic but regular turns to “shift” your blind spots so that traffic can be spotted—this is especially important when departing or arriving at an airport, when there is a higher propensity for vicinity traffic to be either climbing or descending.



1 A small percentage of mid-air collisions occur head-on; nearly all occur in daylight hours in VFR conditions within 5 nautical miles of an airport, usually in the traffic circuit.  Additionally, a pilot is five-times more likely to have a mid-air with an aircraft flying in the same direction than with one flying in the opposite direction.  If an approaching aircraft is seen to be fixed in the windscreen, you are on a collision course; if the approaching aircraft has movement, there is no risk of collision.  Be sure you do not turn the wrong way.  Never turn, climb, or descend into a blind spot.  During flight, the critical areas to scan are 60° left and right of the flight path, and 10° above and below.  In this area the relative airspeed of both aircraft, even if small aircraft, can easily be 250 KNOTS or 455 km/hr—a speed that is hard to conceive of and provides little time for collision avoidance.  Before and during a prolonged descent, turn to clear the airspace below you.  A high level of risk for collision exists during a turn and during climbs and descents.  If the aircraft is flying straight and level, its movement is predictable to vicinity aircraft, who can take whatever action is required to keep clear.  The circumstances are very different when an aircraft begins to turn, climb or descents—the actions of the aircraft cannot be predicted by others, and this is especially the case if the turns, climbs or descend are aggressive or rapid. Once the aircraft departs from the circuit (climbs through 1000’ AGL), you should always begin a series of gentle turns, left and right, so that the blind spots are cleared.  To do this, use 15° of bank, and turn to a heading approximately 30° (to turn further serves no purpose, and turning to a lessor heading will not clear entire blind spots.  To keep on track, a second clearing turn can be done in the opposite direction.  Remember, there is no cost associated with these clearing turns in the climb.  During a climb, a clearing turn should be performed approximately every 30 seconds.  While you are encouraged to turn frequently during a climb, do so smoothly and gently.  For the first 1000’ of the departure from a runway, a clearing turn cannot be performed (unless you feel traffic circumstances warrant it), so before you apply power for takeoff, scan the departure end of the runway for potential traffic hazards—if you see one during the initial climb, manoeuvre to protect your safety.  Prior to turning onto final approach for landing, be sure to scan both left and right along the final approach track to ensure no other aircraft are in the vicinity of the runway approach end.