Caught in the weather…What now?

By Donald Talleur

It’s a beautiful day for flying, so you depart for one of your favourite airstrips for a quick lunch with a couple of friends. Your weather briefing consists of looking up at the clear blue sky. It’s clear in every direction and the visibility seems endless. You decide that the weather must be equally nice at the destination airport. But even if it’s not, you can always turn around and head back to where you departed from. Right?

Well, you load up and head out, only to find that 20 miles away from home base the visibility is somewhat less than you expected. It’s not bad enough to turn around yet, so you press on. At 35 miles out the visibility is now partially obscuring some raggedy clouds close to your altitude. Being safety minded, you decide to descend slightly to maintain cloud separation. Now you’re at 50 miles and you are starting to feel just a little bit uneasy about the deteriorating weather conditions. Your buddies are no longer impressed with the situation and you collectively decide that it might be best to postpone the fly-in lunch until some other day. This decision puts you more at ease but now you are faced with the task of navigating though the goo previously thought to be left behind. At this point, you’re not really sure if you are still legally in visual flying conditions but, being the intrepid aviator, you decide that you can make it back out of the poor weather conditions without assistance. Luckily, you do make it back to your airport and live to relate your harrowing experience to your other flying buddies.

The above tale is not based on fact, but rather was fabricated from several accident reports of visual flights that inadvertently turned into instrument flights. Unfortunately, the real scenario can end in injury or fatalities instead of arriving back home safely.

So what are the problems in our hypothetical flight that might lead to an incident or accident? I’ll bet you’ve picked out several already, but lets review:

1) the first grievous mistake was failure to get an adequate weather briefing. However, sometimes even the weather briefing may fail to forecast poor conditions along a route that has few weather reporting stations. Of course the bottom line here is that the weather can change dramatically in just 100 miles, and in the case of fast moving cold fronts, can change so quick that by the time you decide to make a 180 turn to get out of it, it may be too late.

2) Lowering visibilities and the obscuring effect they can have on cloud cover is extremely dangerous. If you cannot see the extent of the cloud cover or the type of cloud formations, your ability to make any of your own predictions about the current weather is reduced significantly. The best action to take at this point, if not making the 180 turn immediately, is to call a weather service office to get an update weather briefing before pressing on.

3) Was our fictitious pilot an instrument pilot or merely a visual pilot? Accident statistics in the United States show that many accidents are a result of visual pilots flying into instrument conditions. The instrument skills required to safely exit low visibility conditions are minimal, but it is necessary to stay in practice if you do not fly on instruments regularly. If the pilot was certified to fly in instrument conditions, it might have been smart to request an instrument clearance to continue on. However, since the flight was not necessary, it would have been wiser to request a clearance to return to home base.

Another factor the pilot must consider is other traffic that may be operating in poor weather under an instrument clearance. They may not see you in time to avert a mid-air. They may have an obligation to watch for traffic in marginal visual conditions just as you have, but a pilot on an instrument clearance may rely more heavily on the controllers to provide traffic advisories and thus fail to scan for traffic themselves. These types of near misses or mid-airs are rare, but it is best not to test fate. Research also shows that the weather alone is not always to causal factor in weather related accidents, but is usually caused a pilot error in conjunction with poor weather conditions. We can see that in the example flight, the pilot made mostly decision errors in pressing on into the bad weather. Any subsequent skill error may have easily led to an accident.

Low visibility and low clouds are not the only way for the light aircraft pilot to get into trouble however. High winds frequently contribute to landing accidents. It is not unusual for winds to speed up over time during the course of a long flight. Sometimes, the destination winds may be substantially different than forecast. As a result, it is critical to get a wind check upon arrival. In the absence of wind information, it is best to make a low approach and determine the extent of side-slip required to counter the wind for a landing. You can keep the longitudinal axis of the aircraft aligned with the centerline simply by removing any crab required to track to the runway and lower the upwind wing to keep from drifting. If you run out of control travel in accomplishing this manoeuvre, you may need to pick a different runway or different airport altogether.

Don’t let yourself get "caught in the weather." Be smart: Get a good weather briefing, watch for tell-tale signs of impending bad weather, and don’t be pressured into flying in unsafe conditions.