For the purpose of pre-solo consolidation, Tony and I were back at Bald Hill where we had undertaken a few tandem flights prior. The goal of today was to fly repeated approach and landings in preparation for my own first solo flight off either Bald Hill (Stanwell Park) or at Hill 60.
With a 15 to 20 knot Easterly wind atop Bald Hill the glider turns on its pilot and becomes a belligerent machine. Seasoned pilots ground handle with apparent ease although those of us who are just starting tend to behave in comic book fashion while we try and maintain control. Tony jokingly comments that he’s seen more than one glider go astray and fly into the adjoining car park. Mental note to self… don’t let go.
After setting up, strapping in and routine checks, I picked a reference point on the horizon to keep straight and I assumed the second position. Just prior to any takeoff, any good glider pilot will mentally prepare for any variation from the norm the same way any powered pilot does. This includes forward planning for any abnormality or emergency, reassessing wind conditions and plotting the most lift-efficient and safe course after takeoff. I found that the general professionalism of many glider pilots rivaled that of the many powered pilots I flew with over the years.
After calling “clear”, it was only a matter of a few short steps before becoming airborne. I can’t image that feeling of pure vertical lift ever getting boring. Having said that, I’m somebody that gets thrills in the fast moving Sydney Tower elevator so others may not share my childish sentiments. In any case, you can’t help but be bewildered by the rate of climb and initial performance achieved from a glider without any form of propulsion.
Tony has developed a standard approach pattern on which all others are based. The pattern essentially makes the entire approach to land a fairly predictable exercise. In essence, we’re just flying a modified holding pattern into a circuit to land – where the approach pattern is designed to lose height, and the circling approach is a modified circuit onto the beach below. In the early stages of training it’s not normal to soar to height unless it’s a product of training. While others were soaring above, or “boring soaring” as many call it (due to the unchallenging nature of seaside updrafts), I found myself immediately setting up for approaches once I had vacated the comfort of Bold Hill.
The first flying characteristic that becomes overwhelmingly apparent to both powered pilots and first-timers is the exceptional glide performance achieved from the glider. It is so good in fact, that considerable time has to be spent flying a North South figure eight pattern in an area that produces little lift to lose height so an approach and landing can be made. More advanced pilots have their own techniques for increasing the rate of descent to avoid to the need to fly the ‘holding pattern’ but for new pilots especially, the pattern becomes very routine and predictable. The height loss on each leg, the height loss in turns and the turning points themselves are all defined. If the pilot fails to achieve the desired outcome then another safe, planned and predetermined approach can be made.
The control is very different to any conventional aircraft and time spent in the pattern to land is the perfect place to perfect handling the turns. Although experience in other flying machines counts for precisely zip, the aerodynamics and application of flight is a huge benefit. I found myself relating various aspects of flight to fixed wing flying and, at other times, finding the performance of the glider more attune to rotary machines – particularly in the circuit.
Turns are straightforward in the air although they require constant maintenance. Pick a reference point, look out for other traffic (including kites, balloons, seagulls and hills!), shift your body direction in the direction of the turn and maintain a constant sweep of the horizon. I was a little bit slack with anticipating the drift – probably because I’m not used to such extreme crab angles associated with such slow forward speed. As a result, my turns back to the wings level position were rushed and sloppy at times, which in turn made me felt like a pendulum under a large clock. Tony reinforced the need to anticipate the exit from turns and called for less aggressive control (particularly in the turbulence of the day) to dampen the tendency to waffle from side to side. We entered turns at a comfortable speed referred to as trim which is, like motorized machines, a hands-off flying speed that allows for a comfortable attitude that provides for a safe flying speed. With the absence of an airspeed indicator, the pilot becomes more aware of the effects of controls that are literally in his face. You feel the air up against your face and hear the wind the same way you would in a moving car. If the turns feels sloppy and you require more responsive and positive control you can simply pull the bar inwards, which instantly translates to more airspeed.
Of interest to helicopter pilots in particular is the effect of turning downwind. If a rotary pilot makes a downwind turn but fails to maintain airspeed above that required for transitional lift, the pilot may find himself making the counter productive and typical mistake of raising the collective in an effort to maintain height. Fixed wing pilots can certainly make the same mistake but normally fly at faster airspeeds, and lower-time stiff wing pilots normally avoid low-level operations. An air mass can ‘overtake’ an aircraft for a short time, if only for a second of two, which aggravates the downwind situation and loss of indicated airspeed. The same rules apply in a glider. A glider pilot can turn downwind and, if no correction or adjustment is made, the pilot may find himself losing ‘indicated’ airspeed that will likely translate into a sink rate (near the unpleasant end of the drag curve). Tony states that because of the proximity to the ground when turning downwind (which is normally only about 200) the apparent speed can be so overwhelming that it may cause pilots to mistakenly sense that their indicated airspeed is high. The pilot may make the hazardous mistake of instinctively pitching the gliders nose up in an effort to slow down. In an effort to avoid grief in this situation, Tony instructs me to pull the bar in towards me and intentionally fly a faster approach to increase the indicated airspeed and also the rate of descent.
As I approach the base area near a small white footbridge that I used as a reference point, I gently eased the glider into a constant turn onto final. Through the base turn and rolling onto final, an effort is made to allow to the glider to return to trim (by relaxing on the bar) so that when the glider is established on final, the glider has a minimal forward speed. Established on final, I again eased the bar back towards me to maintain a high airspeed and rate of descent to the touchdown point.
In any type of glide, from a Tomahawk to 747, the glide speed should be adjusted with the head wind to allow for the best glide distance. For example, if a Piper Tomahawk is flown in a 70-knot glide into a 70-knot headwind the effective groundspeed is zero – obviously a speed that provides for a less than an optimum gliding distance. Any speed above 70 knots allows for forward groundspeed and ground travel. The actual speed that needs to be flown to achieve the greatest distance can be calculated mathematically but is more often determined from a flight manual. The hang glider pilot, unlike his fixed wing counterparts, remains constantly vigilant of the need to increase airspeed to achieve gliding distance since the typical soaring speeds are often on par with the actual wind component.
Something that has to be considered with every glider approach is the headwind component on landing. The glide distance on final can vary between, say 8:1 and 2:1, depending on wind strength – which makes for enormously different approach perspectives. It’s quite possible to have a glide ratio or 1:0 (relation the ground), or even less, with strong winds. There is some famous footage from the early 80s of one unknown pilot hovering from a height of over 5000 feet to ground level.
Pilots have to exercise caution when flaring. In a strong headwind only a very small flare is required compared to lighter wind conditions where the pilot can afford to be more aggressive with the forward pressure.
After finishing each practice approach to land, one cannot help but be impressed with the way we simply flew to an area of lift and climbed back up to a desired altitude before starting over. A little bit like an un-powered missed approach.
These repeated approaches are made over and over to build both confidence and to ensure that the required standard is met prior to any solo flight.
Next Time: Reflection (Summary)
This blog was initially published in a flying magazine in 2004. It has been reformatted for this blog.
Blog series: Learning to Fly Hang Gliders