Today I put everything I have learned into practice and attempt confined area landings and take-offs. Any unfamiliar or obstructed landing zone can be considered a confined area as the methodology is the same.
A reconnaissance or ‘recce’ of the landing zone should be conducted prior to approach. This is done by flying a circle (typically 1-2nm in diameter, but is dictated by the terrain) at 500ft AGL with the landing zone off the pilot side of the helicopter at about 50 knots. This allows an unobstructed view of the area without committing to a potentially dangerous landing. The recce procedure is PSWATP, as follows:
P: Power check. Confirm maximum power is available as shown on the MAP limit chart by increasing collective. Rotor/engine RPM should remain steady when this power level is held. Confirm minimum power required for flight is available by flying straight and level at BROC speed (53KIAS). Subtract minimum MAP from max MAP. 6” difference allows for out of ground effect hover, 5” in ground effect, 4” zero-zero landing, 3” run-on landing. 6”+ will be required for a confined area landing.
S: Area Shape, Size, Shadows (treat as obstacles), Slope direction, Surface condition, Sun direction, Surroundings, Stock (animals or people)
W: Wind direction, Wires (look for poles/towers not wires themselves)
A: Approach & Departure, do the above factors determine a particular direction for each? Landing directly into wind may be less safe than another approach with a slight headwind component due to LZ conditions. Abort point (use a landmark to determine whether or not to abort, well before you commit to the landing by dropping too low and slow)
T: Termination point should be 2/3rds the way into the clearing to allow ample room for tail boom and safety margin for rotor to the front.
P: Plan. Using the above factors, plan your approach, abort point, landing and departure from the LZ. Everything should be clear before committing. Execute the plan, if things do not go to plan, you can always abort and go around.
When attempting the landing, the exact approach and departure will vary depending on the nature of the LZ, however in the bush clearings attempted in this lesson the logical approach was a double-angle steep landing. Put simply, you approach at one angle and then once you clear a known landmark you descend at a steeper angle until landing.
The departure is the reverse of this, although the initial angle is vertical. As I found out, there wasn’t enough available power for a completely vertical takeoff due to full fuel tanks and two PoB (and a little overcontrolling on my part). This was solved by ‘bouncing’ off of the ground-effect cushion and gaining translational lift earlier on in the climb.