Safety in flying is all about having alternatives. Each trip may offer several different possible routes and a variety of alternates. The departure time and sometimes even the date of departure can be changed if necessary. Once en route, the present and forecast conditions must be analyzed to determine which of various alternatives offer the best possibility of arriving safely at the destination at the desired time. It is also critical to realize when our desired course or an alternative is no longer viable and should be abandoned. Many of the classic aviation accident scenarios, such as continued VFR flight into instrument conditions or attempting an approach under conditions beyond the capability of the airplane or the pilot, are the result of a pilot refusing to accept that the desired path is no longer viable.
A new book by Dr. Dan Ariely titled Predictably Irrational sheds significant insight into why a pilot might continue into a situation when it would seem to be obvious that course of action should be abandoned. Dr. Ariely, who is a professor of behavioral economics at MIT, devised an amazingly simple computer game to examine how people deal with alternatives. The game started with three doors on the screen. The subject would click on a door to select it and then click on it again to open it. Each time a door was opened the subject earned a small amount of money as indicated on the computer screen.
Each player in the study was allotted 100 clicks. It cost one click to select a door, and then one click each time it was opened. Since the player lost a chance to make money each time he switched doors, the most money could be earned by checking each door to determine which door was providing the biggest payout, and then continually clicking on that one door, earning more money each time the door was opened.
After a player had gotten the idea, Dr. Ariely changed the game slightly. If the player did not click on a door it would start shrinking and eventually disappear. Everything else remained the same, and a player would still earn the most money if they ignored the disappearing doors and stuck with one door. It turns out the players could not stand the sight of a door disappearing, and they typically made 15 percent less because they kept wasting clicks to keep all three doors available.
Dr. Ariely raised the stakes even further, adding a cash fee to each click. The players lost even more potential profit as they wasted clicks to keep all the doors on the screen. Dr. Ariely then added one final twist -- after a door had disappeared from the screen, he allowed the player to make it reappear again, in effect keeping that option open even though the door was not visible. Still the players wasted valuable clicks and paid extra to keep all the doors visible. Dr. Ariely surmised that the players were not just motivated by trying to keep the most options open. Instead, they found it painful to watch a door close and were willing to pay the extra price to avoid that pain.
Now let's apply this to a pilot in the cockpit of an airplane in a difficult weather situation. Just as in the game, he would typically face three options. He can either continue on his current course into the worsening weather, he can divert to an alternate, or he can return to his departure point. Added to this equation is the fact that there is only a payoff for making it to the destination, and diverting or returning to the departure point carries a significant cost in terms of both time and money. As long as he continues towards his destination, the other two options remain available. However, as soon as he decides that he cannot make it to the destination and turns around or turns towards the alternate, he has essentially eliminated the door representing the maximum payoff of making it to the destination.
Looking at accident reports, it is obvious that we would do a lot better as pilots if we were more prepared to close a few doors. Let's look at a few examples:
Flight Planning -- I have been amazed at how long I will continue to try to find a way to get to my destination when it should be obvious that it just isn't going to happen. I have also found that the longer I struggle to find a way through in spite of terrible weather, the more likely I am to talk myself into thinking that I have found a way that is "safe enough," often leading to a tiring and sometimes even scary ride. I would have been better off if I had just "closed the door" on that flight as soon as it became obvious it was going to take extreme measures to make it to the destination.
The same goes for fuel reserves. If you are counting on a forecast for strong tailwinds to make it nonstop, plan a fuel stop. It is much easier to decide en route that you actually do have sufficient fuel to skip the fuel stop, than it is to give up the option of making it nonstop once you have determined you are going to try to do so.
En Route -- Similar reasoning should be applied as the weather starts to go sour. The farther you proceed into bad weather, the less likely you are to turn around. As you get closer to your destination, the Proximity Rule also comes into play. The destination becomes like the tractor beam on Star Trek, pulling you towards the destination. It is not so hard to turn around just after you take off, but giving up a few miles from the destination can be almost impossible. A pilot who is halfway to his destination and getting low on fuel will land to get fuel. A pilot only a few miles from his destination will tend to keep going rather than take the time to stop at an airport short of his destination.
Approach -- If the conditions are right at the borderline of your limits, it is much safer to make the decision to divert early. The closer you get to the runway, the less likely you are to abort the approach, no matter how bad it gets. One time you should absolutely and automatically close the door is when you "take a look" and don't see the runway. Unless conditions have improved or you know why you missed the approach, attempting the same approach again is almost guaranteed to result in going below minimums to try to break out.