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1. Perform pre-takeoff checks, and carry out a power check at the low hover;
2. look out, pick references in front and side to ensure a vertical ascent;
3. smoothly apply collective gradually to initiate a gentle vertical climb, adjust cyclic to ensure the climb is vertical by use of references;
4. as the top of the obstacle is reached, ease forward on the cyclic to increase airspeed, make small movements and ensure the aircraft is still climbing before introducing forward flight;
5. when clear of the obstacle, and after attaining translational lift, set normal climb attitude and power; and
6. Make a good lookout all around as you clear the obstacle.
When using this technique, be careful to set a low rate of climb, especially when heavily loaded, because as you lose ground effect you could stop climbing and have to descend. If you use a large amount of collective for a high rate of climb, you need a large amount to stop the helicopter descending and overcome inertia built up on the way down. This could lead to exceed aircraft limitations.
NO-HOVER LANDING
This type of landing is used when it is undesirable to approach to the hover, generally because of snow, dust or ash. It should also be noted that it requires less power than a normal approach and could be utilized in situations where power requirements are high, e.g. heavy loads, hot and high altitude operations:
1. approach the landing area as required; and
2. as the landing spot is achieved at zero groundspeed apply sufficient collective to cushion the landing.
The surface of the selected spot requires a good reconnaissance to confirm its suitability for this type of landing.
RUN-ON LANDING
This type of landing is similar to a No-Hover except it requires less power, but a flat, smooth surface is essential, preferably cleared with a reliable reconnaissance:
1. approach as required;
2. gradually slow the helicopter to a slow walking pace and use sufficient collective to cushion the landing while running on; and
3. after landing, maintain cyclic and collective positions until forward motion stops.
APPROACHES
1. Steep approaches are used when there are obstacles on the approach path or operational conditions require using this technique. Apparent groundspeed will be lower than normal and more power will be required. It is of importance to maintain a low rate of descent on the final stages of the approach to avoid any chance of entering vortex ring state.
2. Shallow approaches use less power than standard or steep, but require an approach path, which is relatively flat and free from obstacles. The technique is used where conditions limit the power available, or where you have maximum power but it is insufficient to use normal procedures. Do not make the approach angle too shallow as this could lead to the use of high power settings, and near the ground, when decelerating the risk of tail rotor strikes.
EXERCISE 25 - CONFINED AREAS
One of the helicopter’s most often used capabilities is that of being able to operate in relatively unimproved locations, and to land and take off from confined areas (Figure 25-1) which may be bordered by buildings, high trees or other obstacles. It is essential that the helicopter pilot learn how to operate the helicopter safely in this environment and be able to take full advantage of this unique ability.
You may consider this exercise in seven steps as follows:
1. High or Initial Reconnaissance. Your very first step is to positively identify the area in which you wish to land.
Figure 25-1: Confined area
The initial reconnaissance should generally be flown in a circular pattern to the pilot’s side at airspeed of between 50 and 80 mph. In any event the speed should be such to allow a good view of the area throughout the pattern and allow for adequate controllability. The height may be that of arrival at the area but should generally be in the order of 1000 feet AGL. If you are already flying at about 500 feet AGL then you may consider combining the high and low recce into one. Combining the two as you gain more experience will become the normal technique. Variations in the basic confined area technique will be demonstrated as your course progresses.
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