I have always wondered how pilots can fly a whole day without taking a break. Even pilots that are technically much more skilled than I am, and can land at much tougher places for a rest, seem to prefer flying hours on end rather than resting now and then. During long flights, you need a break to get some fresh energy. To calm down and reflect on your current situation and position. With your feet on the ground, you will be able to observe and reflect clearer than while being busy flying and looking for your next thermal.
After two to three hours, I prefer to land and relax a while, piss, eat, have a look at the wind direction (easier to observe than in the air), reconsider my (original) flight plans, repair something broken, et cetera. For flatland pilots, this solution probably means they are grounded, unless they land near a winch. But all those lucky pilots that fly mountainous areas such as the Alps, will usually find a nice spot to land (and take-off again!) when needing one.
Spring is my favourite season for toplanding. Summits tend to have teeth that could easily mangle your wing or an ankle. None of this in spring, when the rocks are still covered with a welcoming carpet of snow. Just be aware that taking off can be a bit of work if there is either little or strong wind. Running and anchoring respectively, are difficult in this case. And for those who always wondered why I insist on a blue and white wing being best adapted to free flight (and vol bivouac in special), the answer is just a click away.
Fatigue is a major contributor to incidents. Often reinforcing the pilot's inflated self-confidence that caused it to occur in the first place and at the same time dulling the pilot's awareness of the difficulty and dangers that the environment poses. The longer your flight, the more chance that incident frequency will go up because you are getting tired. Eventually, there will be a last incident that turns into an accident. Being tired deteriorates your thinking, reflexes and conscious actions. You think and act more slowly, while at the same time your thoughts and actions are more likely to be wrong. A collapse close to a hill side might be adequately handled at the beginning of your flight, but a similar incident several hours later could easily lead to a cratering experience.
How often have you seen lousy flying of pilots that simply had no energy or mental vitality left for a proper landing at the end of a long flight? Perhaps the following scenario sounds familiar. You have done an exhausting flight in what essentially turned out to be non-flyable conditions. But you have done an excellent job in managing those challenging circumstances. Being alone in the air all day, all other mortals being on the ground, you feel like a sky god. Conditions finally have calmed down and people have just started from take-off for their evening flight, after waiting for it since breakfast. You profit from the calmed down conditions to add another forty kilometres to your flight distance. You are finally going to make that large triangle that has been teasing you for a while. Those last kilometres are indeed peanuts, in comparison with the rest of the day. Less than two hours later you come in for a landing. People on the landing field can actually see that you are tired, because you are flying like a bag of potatoes. And you land like one. As the sun gently drowns in beautiful red colours, you are lying in a field full of donkey shit. And you feel like one. You can also feel the ants crawling in and out of your leg, that has a open fracture. While you wait for the ambulance, you can observe the (near perfect) landings of the pilots on their first flight. There really was no need to crash.
In order to limit these kind of scenarios from happening, I try limiting my flying to about five to six hours a day. Such a long flight should at least include one break. If conditions are more demanding than average, I will have more breaks or less hours. To measure my tiredness, I use the incident or (near) collapse count. I have very few large collapses during a season, let alone during a flight. Most collapses can be prevented by feeling them coming and acting accordingly. Some of the big ones are inevitable when flying rough conditions, but even most of them can be prevented by going with the flow of the air. You just need to act timely and with the correct input. Being tired means being less sensitive of what is going on around you, including the air's movements. When tired, my thinking and reflexes are too slow and my actions wrongly dosed or executed. This results in (tiny) collapses or similar incidents that try to tell me that I am flying sloppy. Hopefully I am listening. It usually starts with an occasional flapping of the wing tips, followed by tiny collapses later on. I am not going to wait for the big collapses that are bound to happen further down the line.
When the incident (or collapse) frequency sharply increases, it is either time for a rest or time to call it quits. For example, when doing the standard trip Lachat de Châtillon - Trélod - Dents des Cons - Pointe Percée - Grand Bornand, there are unlikely to be collapses for most of the flight. In the last part however, for example near Charvin (a bit of a rough place now and then), I suddenly might have two or three collapses within a few minutes. That is why I prefer taking a rest a few kilometres earlier on near Marlens. Sometimes this rest is imposed because I missed the transition from Dents des Cons. Usually I do not regret an imposed rest. It tells me I have made an error, most likely because I am tired. It is better to make an error that lands me, rather than having luck and making an error that crashes me later on because I am tired. If the collapse rate (once again) increases while flying near Les Confins, it is time to call it quits and land at nearby Grand Bornand. Or Le Bouchet if conditions impose it, since that tends to be a bit calmer place than Grand Bornand itself in the afternoon. Continuing to fly to Pointe Percée (and then back to Grand Bornand) in this case, has a high risk of one incident too much occurring. An incident turning into accident.
To some it might seem that the above collapse rate example is due to the Aravis chain itself. Let me assure you, it is not. The Aravis has some decent challenges here and there, but is an area that I know well enough to avoid surprises. And if I do the trip the other way around, the collapse rate will go up when arriving at places such as Dents de Lanfon, Tête à Turpin, Mont Lachat or Jallouvre. These places trigger collapses because they are at the end of the flight here. Because I am tired. Not because they are nasty. They hardly cause collapses when doing this trip counter clock-wise by starting from Lachat de Châtillon.
Whenever incident frequency, or rather my mistake frequency goes up, it is time to rest or stop the flight. And as a final warning for those who still think they might get away with it, the 'I am too tired but I do not (want to) know it yet' incident usually arrives when you are least expecting it. For example, I like flying in Les Écrins because of its beauty and wildness. It is pretty challenging terrain though and demands matching concentration and skills. Now guess what happens when I (am about to) leave Les Écrins? Indeed: my brain relaxes and my concentration wanes. Suddenly I could find myself in serious trouble. In a challenging situation that I would have expected (and be prepared for) in Les Écrins. Not here in this 'easy' area, not now. This dulling disillusion happened several times after successfully crossing difficult terrain. Even when I am prepared for it by now, it still catches me nearly off-guard now and then. Risk management basically is a simple affair: do not get hurt. But simple does not mean that it is easy.