If youre wondering what instrument flying has to do with visual flight rules (VFR) flying, the fact that is both activities should include accurate height and heading control. Proficient instrument flying is in large part the accurate and disciplined control of altitude and direction, but this is part of good VFR flying, too. Unfortunately, many VFR pilots, especially those who fly in remote areas, have poor control of height and heading.
Some aviation authorities require instrument training for basic pilot licensing/certification, reasoning that pilots with this training, should they encounter inadvertent instrument meteorological conditions, will be better able to manage until they can re-establish in visual conditions. Those who strongly advocate that VFR pilots should always keep the ground in sight view this reasoning with raised eyebrows, but most agree that good height and heading control is a mark of good helicopter flying, no matter what the weather is like.
The helicopter is not a stable platform, and VFR pilots generally use outside references to keep it upright. To fly VFR accurately, however, pilots need to learn how to scan both outside references and inside instruments. Additionally, if the instrument rating is the next step on your career ladder, good height and heading control is an essential prerequisite, and one that makes instrument training much easier.
Helicopter forward flight put simply is climbing, descending, turning, speeding up and slowing down often in combination. These changes in direction and momentum are brought about by manipulating attitude, power and roll about the longitudinal axis.
To do this with instruments, some basic rules of thumb are required, such as the rule to begin leveling out from a climb or descent at an altitude equivalent to 10 percent of the vertical speed in feet per minute. For example, to level out from a climb/descent rate of 500 f.p.m., begin to establish level flight smoothly 50 feet prior to your anticipated altitude.
Another rule is to begin rolling out of a turn at a number of degrees before the desired heading, equivalent to half the required bank angle (although, its probably a good idea to start anticipating even earlier). Use the turn-and-bank or turn coordinator for a Rate 1 (two-minute) turn, and crosscheck your bank angle on the attitude indicator (it should be 10 percent of the indicated airspeed plus seven knots for smooth and accurate control).
Now, lets apply these rules to some basic instrument maneuvers in flight.
If your helicopter cruises at 110 knots and climbs most efficiently at 60, try 100 knots for straight and level and 80 for climbing and descending when practicing instrument flying. The lesser transition between the two attitudes will be much easier to control.
To climb and turn as one coordinated effort, climb in proportion to the progress of the turn. For example, if you plan to climb 500 feet higher and turn through 90 degrees, coordinate the maneuver so you climb through 250 feet as you turn past 45 degrees, continue monitoring the climbing turn, and then remember the rules for leveling and rolling out.
Accurate height and heading control leads to more efficient performance on the job, and can even allow for a slower helicopter to outperform a faster one. For example, a friend of mine once asked me to help him airlift passengers from a resort to an airport 40 minutes away. His helicopter was faster than my two-bladed steed, and he would beat me to the landing on every flight. Curious to see if I could make up for the speed deficit through efficient heading and altitude control, I came up with a plan.
On one of the flights, I used the radio to lead him to believe that I, too, would be climbing to 7,000 feet to clear the mountains in the area. However, I calculated that 6,600 feet would safely clear the terrain, and on the way up I carefully monitored climb attitude, heading, power setting and trim. After leveling briefly at 6,600 feet, I started down and could see my friend above me and slightly ahead, enjoying the scenery. With the Vne (never-exceed speed) chart in front of me, I lowered the collective partially and dropped the nose, quickly reaching the helicopters maximum speed. As the altitude rapidly decreased, I increased the airspeed in accordance with the Vne chart and began to assess when to flare for the final approach. My friend was in utter disbelief when he heard me call my approach ahead of him, and then on his short final he was aghast to see me sitting at idle, off to one side of the pad.
Although some pilots may not see the importance of maintaining accuracy with heading and altitude, doing so is good airmanship. Instrument pilots have the skills required to control height and heading with reference to only basic instruments, and VFR pilots should strive to develop the same fundamental skills.