Controlled Flight into Terrain (CFIT) "accounts for 17 percent of all general aviation fatalities ... ." (FAA Advisory Circular 61-134, p.1). One type of CFIT accident involves visual flight rules (VFR) only pilots, i.e pilots without an instrument flight rules (IFR) rating, flying in marginal visibility or in instrument conditions.
The practice of attempting to maintain visual flight in marginal visibility or in instrument conditions is referred to as scud running. "CFIT occurs when an airworthy aircraft is flown, under the control of a qualified pilot, into terrain (water or obstacles) with inadequate awareness on the part of the pilot of the impending collision" (FAA Advisory Circular 61-134, p.3).
Many pilots scud run, some live. Some don't.
It is Sunday afternoon, time to go home after a pleasant weekend away visiting friends not far from the mountains. You are worried about the weather, there has been talk of a rain storm coming from the west. You have to fly west to go home, perhaps a 175 nautical mile (NM) flight. You might be able to make it in under 1.5 hours in your Cessna Cutlass.
You get a weather briefing, the bottom of the cloud deck is currently at 3,000 ft above ground level (AGL), but conditions are forecast to get worse with lower ceilings at about 1,200 feet expected at your home airport in about 1.5 to 2 hours. The mountains between you and home climb anywhere from 2 to 4,000 feet above the elevation of the airport where you landed on Friday,. But you have flown this route before and know where there is a highway that travels at a lower elevation through the mountains.
You and your son get your things together and drive to the nearby airport. You fueled the plane after landing Friday morning. You are set to go. You take off heading west and level off at 2,500 ft AGL. You find the highway west after a few minutes of flying. Some of the taller mountain tops are shrouded in clouds. You had a GPS installed in the Cutlass recently. There are still a few features that you need to figure out.
You fly along at 2,500 ft AGL for about 20 minutes, glancing down to check your GPS every so often. You continue to follow the highway.
But then things start to get worse.
Ceilings are lower than forecast, so as the bottom of the cloud deck gets lower, you fly lower and descend to 2000 ft. AGL. As you fly along, the cloud deck continues to get lower and you fly lower and lower until you are just under 1,000 ft AGL flying perhaps a couple hundred feet under the clouds. Several minutes pass and it starts to rain, you aren't worried about the rain because your outside air temperature gauge says that the temps are about 45 degrees F. You are now at about 600 ft above the highway and your eyes are glued outside the cockpit looking ahead at the road below. You are OK because you know where the highway is. On a couple of occasions you have followed the highway west flying VFR, and have also driven west along the same road.
You are losing sight of the highway. Where is it? You fly lower. Oh, is that it down there? You don't know. You keep flying. You don't see that the Terrain Avoidance Warning System (TAWS) in the GPS is flashing, first yellow and then red. When you see the mountain it is too late. You pull back on the yoke and take your son's hand. Too late!
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The above scenario is fictional. There are many real fatal accidents in the NTSB database where the pilot attempts to maintain visual flight in instrument conditions resulting in a controlled flight into terrain. I've read some of them.
The AOPA Air Safety Institute's video, 178 Seconds to Live depicts a similar scenario to the fictional scenario that I have described above. There is no GPS, but you will get an idea of what you might see from the cockpit when a VFR only pilot ends up in instrument conditions. I was not able to get the embed code to work, but you should be able to watch the video from the link I provided. Added on December 18, 2014, I have updated the link to the 178 Seconds to Live video from the AOPA Air Safety Institute. A heads up that I was unable to get the video to play in my Firefox browser but it worked in Safari and Chrome. For those you who are interested in seeing the video (I recommend it), there is a similar video that I found from the Civial Aviation Safety Authority in Australia (go here) on YouTube.
I'd like to thank the staff of the Air Safety Institute who assisted me as I was researching this article. I'd also like to thank my pilot friends and my friends at my home airport.
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