Lookout

(Thanks to the Darling Downs Soaring Club for permission to reproduce this item which was published in a recent edition of the DDSC Newsletter, CHAOTIC)

Lookout is a fundamental skill and often taken for granted in flying instruction. Very little explanation is given on how to develop the correct habit patterns or use the correct techniques. If you use a fairly standard work cycle for flying ATTITUDE - LOOKOUT - PERFORMANCE, the lookout part of the cycle should occupy >85% of your time, however most of us take a considerable amount of time to develop the correct technique. The following text should help in explaining the techniques you need to develop to have an effective LOOKOUT.

The best technique a pilot can use in searching for aircraft is the object of considerable dispute. Some schools teach that the sky should be divided into many small segments, say 30 by 30 sectors, and each sector should be searched thoroughly for several seconds to ensure it is clear of aircraft before shifting to the next sector, and so on. Other schools suggest that the eyes should be moved constantly, never being allowed to stop unless something requires closer investigation. As might be anticipated, each of these techniques has strong and weak points.

The brain cannot interpret visual images when the eyes are moving. When a person scans a wide area quickly, the eyes actually move in many small jerks, pausing repeatedly for a fraction of a second to allow the brain to interpret what is seen. In order to search a sector as thoroughly as possible, the eyes must be focused at the proper distance. Unfortunately, the eye does not provide us with a reliable indication of focal distance. This distance can only be determined by estimating the range to an object in focus. When the eyes have nothing on which to focus, such as when a person is staring into blue sky, they tend to focus at just a few feet away. This focal range is closer to the canopy than to the bogey, so spots, smudges, and scratches on this surface tend to attract the focus of the eyes.

The problem of focus can seriously degrade visual effectiveness in the air. The usual technique is to focus on a distant object, such as a cloud or a surface feature on the horizon, and then quickly shift the scan to the area of interest. The eyes can usually be held in focus at long range in this manner for a few seconds before the procedure must be repeated. Experienced pilots normally do this continuously and even subconsciously as they shift their scan from place to place. A lack of a technique for focusing at a distance is probably the primary reason inexperienced pilots see very little in the air.

In daylight, maximum visual acuity is found in the very centre of the scan, in an area that covers only a fraction of a degree of arc around the midpoint. Any object outside this very small central area is generally detected by peripheral vision only if it contrasts markedly with the background, is very large, or shows relative motion. (It is primarily motion that catches the attention of peripheral vision). This explains the value of a radar Target Designator (TD) box in modern fighter aircraft. When the radar locks on to a target a small square appears in the Head Up Display (HUD) as an indicator for obtaining the earliest possible tally on a bogey. The TD cue normally indicates the position of the bogey, usually within less than 1 of its actual position. The pilot can then search carefully near the indicated point in space (sometimes called "spot scanning"), generally with the aid of HUD images focused at infinity to help in finding and holding proper focal range, and can detect very distant and low-contrast targets (15nm +)

The smallness of the area of maximum visual acuity limits the effectiveness of detailed sector search unless the target's line of sight can be limited substantially. It can take several seconds to scan thoroughly an area extending even 1 about a given point. Therefore, dividing the entire world into sectors for consecutive detailed inspection becomes ludicrous. Even if each individual search were limited to only one second, it would literally take all day to complete even one cycle of this process. Based on such realities, it just isn't practical to rely on a detailed sector-search scan technique to produce acceptable results for glider operations. However in the military when in an offensive position, fighter pilots will carefully inspect narrow sectors, as this method usually yields tallyhos of the longest range.

For gliding operations the alternative is to devise a scan technique based on peripheral vision, which allows coverage of a very large area in a relatively short time. This method involves moving the eyes (and the head) back and forth across the entire field of view at a fairly rapid rate. Although the head may appear to move smoothly during these sweeps, the eyes will actually make rapid jerks of several degrees at a time, and a fairly large area can be searched by peripheral vision at each pause. This technique is somewhat analogous to speed-reading methods, as opposed to focusing on individual words on a printed page. The actual speed of the scan is dependent on proficiency, as the eyes must be trained to make these movements faster for greater scan speed. If the eyes are not allowed to pause repeatedly, very little will be seen.

There should be a regular pattern to these visual sweeps; both above and below the horizon and from forward to aft visibility limits on both sides of the aircraft should be searched. The scan should be allowed to sweep distant objects periodically (every few seconds) to provide adjustment of focal range. No sector should be completely ignored for extended periods. One of the main reasons fighters fly in pairs is that it allows each pilot to concentrate his search toward his wingman, and multi-crew fighters can divide visual search areas of responsibility for maximum efficiency.

Another useful technique is to move the head forward and back, and from side to side during the scan process. This helps clear areas hidden behind canopy rails, etc., and also aids in reducing the distraction of canopy scratches, bugs, and spots. Anything on a canopy will appear to move opposite to the direction of head movement, and the brain can use this motion to "filter out" these objects from external targets, which do not react to pilot head movement. A truism in the fighter community is that there are two categories of fighter pilots: those who have performed, and those who someday will perform, a magnificent defensive break turn toward a bug on the canopy.

Although use of peripheral vision as the primary scanning mode does not generally result in tallyhos as distant as those provided by the sector-search method, the chances of seeing another aircraft are greatly enhanced, and this is the more important objective.

So now you are armed with this new knowledge, how do we put it into action? The first step is to take a disciplined approach to manoeuvring your glider. For example if you wish to make a Left turn, before moving the stick, say and do the following actions. CLEAR RIGHT - ABOVE FRONT and LEFT - and then move the stick to the left. In the right, front and left sectors make sure you consciously focus on a distant object. It should take you only about 5 seconds to complete a full scan. The technique has a couple of added benefits, by the time you have completed the scan you are probably close to the centre of the thermal and if the Lift has dropped off, it probably was not worth turning in the first place. For those of you who think this a labourish method, it has been used in basic military training for many years, with students being made to verbalise their lookout technique for their first 25 Hrs of flying. In normal flight a section of the scan can be completed every work cycle. In Cross Country flight lookout can be concentrated into threat sectors depending on the manoeuvre you are performing. For example if you are pulling up and slowing down, you may be entering the blind spot of another glider that is above and travelling faster so above and behind should be the first sectors scanned. In exactly the same way, when pushing over leaving a thermal, a slower glider below is the main threat and therefore left and right under the nose needs to be scanned.

When flying in close proximity to other gliders always assume the other glider has not seen you and it is your responsibility to take avoiding action. Even the best pilots can be distracted by the latest GPS wizardry. A good lookout is developed over time and you need a disciplined approach to develop it. Try verbalising your lookout and focussing on distant objects as you scan the sectors around you aircraft and you will be amazed at how much more you will see.

Geoff Brown

Download as a Word document (34Kb)

Return to Main Lookout Page