As you set off across the Fieschertal towards the terrain above the village of Bellwald, the location of thermals there will often be well marked by climbing gliders ahead. When you have begun your transition from anywhere east of Eggishorn with at least 2,800m, you can expect to be in a good position to connect with lift in this area. Starting from that height, I usually aim at the lake at Richinen, which is easy to identify from some distance away, as there are also a few buildings and a junction between two chairlifts there.
As you near this area, you should be aware (from observing your ground speed and any sideways drift on your glide) of the wind speed and direction, which can have an important effect on the climbs here. Your first option is likely to be a thermal tracking up the slope near the upper chairlift cables, which usually works well in a westerly. However (especially if early in the day, and without a meteo wind in between west and south) you may well encounter a light easterly wind there which stifles it, so you are more likely to need to glide onwards to get around the corner of the shoulder into a large sheltered gully, which tends to provide a larger and faster climb in most conditions. Beware of this option in a westerly wind over 10km/hr (indicated by vigorous flapping of the flags by the Richinen lake) which often accelerates horribly around the shoulder and renders this thermal unusable; in that case I stay on the windward side. If you are unlucky enough to encounter a significant breeze between north and east blowing down the slope at Richinen, you may be tempted to try to push on around the corner in the hope of either finding a windward face or escaping this wind altogether, but this has never worked for me. I would recommend staying in the full lee (provided the turbulence is within your limit) to try to fight your way out vertically in the thermals which are (hopefully) punching through the descending airmass.
From a lower start from the Fiescheralp side, e.g. due to low cloudbase (in which case this should be from further north where the crossing is shorter) a route traversing the south-westerly facing slope is often buoyant, as it can also work well here surprisingly early. At village level, the car park at the top of the cable car coming up from the train station at Fürgangen is often a good trigger point for a decent thermal.
Lower still, I would suggest two alternatives. There are often substantial well-formed thermals above the south-easterly face beyond the village, usually much further out than you might expect, as they seem to break away early and rise vertically, rather than tracking up the slope and releasing at the shoulder where it becomes less steep. You do not need to feel apprehensive about being cut off from landing at Fiesch if you commit yourself to this south-easterly face and go down, as there is a landing option at Niederwald, just east of the station. The other possibility is to glide over the spine leading from Bellwald towards the Fiesch landing field, off which there will usually be plenty of thermic bubbles releasing, but using these to get back up again is likely to be slow and tricky.
Because of the potential for thermals to be coming up both faces at the same time (and skidding across the south-easterly facing slope even in a very light south-westerly wind), finding rough conditions in this area doesn’t mean you should expect to be battered around throughout the Goms, so if there is turbulence here which is pushing at the limit of your comfort zone, don’t lose heart!
Once you have got up at Bellwald, your route along the Goms will be determined by the height of cloudbase, and the degree to which it extends outwards from the higher terrain on your left towards the valley on your right. If base is low but there is good cloud development over the shoulder, a safe line nearer the valley on your right is usually fine, but it is wise to top up with every decent climb unless there is a continuous line of convective cloud. When base is high, heading deeper in towards the higher peaks to the left should work better, as the lift there is likely to be stronger, and on really good days you may be able to just dolphin along without needing to turn at all. Usually, the thermals are spaced so closely together that it is easy to maintain ground clearance of several hundred metres as you progress up the Goms. From around Münster onwards (the large village about half way along, just past the nearer of the two runways visible in the header image on this page), the height of the spine of the ridge to your left gradually declines, from the Firehorn at 3182m to the Sidelhorn at 2764m. To avoid the effect of the Grimselschlange, you should aim to take a line further in than the shoulder. I often see pilots crossing to the north of the spine, but this prospect makes me nervous as there are no reasonable landing options on the other side. I have learned that it’s informative to keep an eye on my GPS to monitor ground speed/wind direction; if it keeps showing significant variation from one minute to the next, watch out for turbulence near the head of the valley, even if the air along the ridge has been feeling relatively smooth.
The track log above shows a flight in weak thermals with a relatively low cloudbase. Despite the 3000m ceiling, I was able to edge nearer the main spine of the ridge as I approached the head of the valley in order to evade the Grimselschlange, but the ayvri visualisation illustrates how the relatively light conditions resulted in a rather meandering line, with less than ideal height (that’s my excuse, anyway).
On better days, it’s much more straightforward. The track log below shows a flight with cloudbase approaching 4000m, enabling me to take a considerably higher line with much faster progress, getting above the spine of the ridge before the Sidelhorn and using lift coming up both sides.
Once you have reached the Sidelhorn, you will need to make up your mind between a return back towards Fiesch from here, taking a more demanding turnpoint beyond the Grimsel Pass, or a commitment to crossing the Furka Pass into the Urserntal. It’s unusual to come back into the Goms again from the Urserntal, but by no means impossible. If the lift becomes scrappy here, and you observe that the number, size, and duration of the convective clouds here is declining compared with the rest of the Goms, this suggests a relatively strong northerly influence, which will cause tricky conditions if you decide to continue heading east. Look out for flags and the texture of the lake in the col of the Grimsel Pass to provide some indication of the strength of the Grimselschlange, which you must steer clear of at all costs.
Unless you can be certain that the Grimselschlange is absent or very weak, avoid landing near the head of the valley at Oberwald, as it tends to be very windy there; if you’re failing to find lift or want to conclude your flight, it should be easy to glide back to the official landing field at Ulrichen, 5km to the west, unless you have allowed yourself to get very low indeed.
If you turn around to fly back towards Fiesch, the return leg (leaving aside the effect of any prevailing wind) is usually much easier than the outward trip, due to the tendency of base to rise and thermals to strengthen during the day. A few times, I have been able to simply dolphin back the whole way, without needing to turn at all. When you arrive back at Bellwald, bear in mind that you may need an escape route from cloud out into the valley, in case you realise only after you have been enjoying a super climb there for a while that you are actually in a large area of strong convergence, rather than just a better than average thermal.