Figure 15-1: Typical Helicopter “Race Track” circuit
Lift the helicopter into the hover and perform a clearing turn, commence a standard transition, and:
1. at 300 feet begin a climbing 180° turn and roll out on the downwind leg at 500 feet AGL. The angle of bank should not exceed 30° and in fact should be varied according to the existing wind conditions, so that the downwind leg is approximately one-half mile from the take-off departure leg and parallel to it;
2. on the downwind leg, perform a pre-landing check. When you are flying circuits a radio call should be made on the downwind leg to advise the ATS, if you are at a controlled airfield, and other traffic of your intentions as to a landing or an overshoot; and
3. when the helicopter is at approximately 45° past the touchdown point, roll into a 180° descending decelerating turn to the final approach path to set yourself up at 300 feet AGL and 60 mph, approximately one-half mile back from the landing point. (The speed will of course vary according to type, but will generally approximate the best rate of climb speed).
SQUARE PATTERN
Figure 15-2: Typical Helicopter “square” Circuit
The square circuit varies slightly from school to school as far as heights to fly but the basic pattern is the same. The example below is just one variation.
Lift the helicopter into the hover and perform a clearing turn, commence a standard transition, and:
1. begin a 90 degree climbing turn at 350 feet AGL and roll out still climbing on to the crosswind leg. Level off at 700 feet AGL,
2. turn on to the downwind leg and perform a pre-landing check when abeam the intended touchdown point,
3. when the helicopter is 45 degrees past the touchdown point, lower collective to begin a descent and turn 90 degrees on to the base leg. At the same time, set the attitude for 60 mph, and
4. start your turn on to the final approach at 450 feet AGL, roll out when lined up with your take-off path at 300 feet and 60 mph, approximately one half-mile from the landing point.
SPACING
It is extremely important that you be constantly aware of the position of other aircrafts that may be operating at the same location. This is of even greater significance if there are fixed and rotary wing aircraft operating at the same airfield. You must fly your circuit taking into account other helicopters that may also be conducting circuit practice, and maintain a suitable distance from them. You may have to change your touchdown spot so that you do not interfere with their operations. Remember that displaying courtesy is also good airmanship. If you are operating at an airfield where there is a mix of both fixed and rotary wing, the exercise of good judgement and consideration for other pilots becomes most important. It will likely be necessary for you to arrange your circuit to remain clear of the fixed wing circuit, but seek approval from the ATS to fly a circuit opposite to that being flown by the aeroplanes. This may also mean that you may not be able to arrange the circuit so that you are directly into wind for the takeoff and approach. You may not encounter this difficulty at an uncontrolled airfield, but in any event, you will find that the ability to arrange your circuit so that it causes no disruption to other traffic, will not only be appreciated by other pilots, but will result in safe flight operations.
WAKE TURBULENCE
Numerous aircraft incidents and accidents occur at the busier airports as a result of wake turbulence, despite the many studies on the subject and the increased publicity among the pilot community. While these occurrences primarily involve light aeroplanes, the helicopter is also vulnerable if the pilot selects a flight path that intrudes upon the turbulence generated by airflow from the trailing edge of an aerofoil.
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