The Oldest Trap In The Book
Don't Fall Prey To Continued Flight Into Bad Weather
Tragedy Over The Water
Once again, the media spotlight was turned on general aviation, specifically the risks associated with flying visually at night. In the ensuing frenzy of coverage, the talking heads spouted a great deal of misinformation. However, they did get one fact right: Pressing on into deteriorating conditions can be a lethal decision. In fact, according the AOPA Air Safety Foundation's 2000 Nall Report, more than 75 percent of fatal weather-related accidents were caused by "attempted VFR (visual flight rules) flight into IMC (instrument meteorological conditions)."
The Accident Scenario
What makes continued VFR into IMC accidents so deadly? First, unlike landing or takeoff accidents, where the speeds are relatively low, these accidents invariably result in a high-speed, high-G-force impact with terrain. Second, once a VFR-only pilot loses visual references, the situation deteriorates rapidly, often becoming critical in seconds.
Although no two continued-VFR-flight-into-IMC accidents are exactly the same, the accident reports do suggest two common scenarios. Both begin when a pilot is faced with deteriorating weather along the route. Invariably he elects to continue toward the destination by either climbing above the weather or descending below it.
In the first case, he soon realizes that his aircraft's performance is no match for the fast-rising clouds, and he soon finds himself in the soup again. Within a matter of seconds or perhaps minutes after losing visual references, he becomes a victim of spatial disorientation. He cannot tell which way is up, mistrusts or cannot interpret attitude-instrument indications, and loses control of the aircraft. If the aircraft's limitations are exceeded, structural failure can occur. The end result is usually an uncontrolled, nose-low, high-speed descent into the ground.
In the second case, the pilot descends ever lower to avoid the weather - until he is trapped between an overcast layer above and the ground below. With nowhere to go and the weather closing in ahead and behind, the pilot flies on, just above the terrain. The end result is usually a controlled flight into terrain or CFIT accident, in which a perfectly flyable aircraft collides with either terrain or an obstacle (see "Avoidable Accidents: Tips for Preventing Controlled Flight into Terrain," February AOPA Flight Training).
Minutes To Live
To understand just how quickly these situations develop, consider this recent report from the National Transportation Safety Board.
On May 28, 2001, a Cessna 210 crashed into hilly terrain near Escondido, California, fatally injuring the commercial pilot - who was instrument-rated but apparently out of practice - and his two passengers. The airplane departed Ramona, California, at 11:40 a.m. on an instrument flight rules (IFR) flight plan to Fresno, California. Instrument meteorological conditions prevailed at the time of the accident. The aircraft was radar identified and was com- municating with approach control.
The first indication that something was amiss came six minutes after departure. At 11:46:26, in response to a query from approach control, another pilot aboard the airplane said, "Stand by, we're in a little trouble here." The controller made two subsequent calls to the accident airplane. At 11:46:39, the pilot in command replied, "Uh, Six-Two-X-ray, stand by a second." At 11:46:56, the controller issued a warning that the airplane was heading for higher terrain and instructed the pilot to turn left to a heading of 270 degrees and climb. There was no response from the pilot. At 11:47:17, the airplane began a steep left turn from an altitude of 4,700 feet mean sea level (msl). The airplane was observed turning left to a heading of approximately 180 degrees and descending from 4,700 feet to 2,500 feet, and then climbing back up to 3,100 feet. At 11:48:39, radar contact with the airplane was lost.
In this case, just two minutes and 13 seconds elapsed from the time trouble was first reported over the radio until the time radar contact was lost - and this pilot held an instrument rating. Without a doubt, spatial disorientation occurs rapidly and with devastating results.
Flawed Decisions
What is troubling about this kind of accidents is that the pilots don't seem to consider other options besides pressing on. In most cases, they have ample time to avoid trouble, yet they continue right into it.
It is as if they suffer from tunnel vision and cannot see any solution other than continuing, succumbing to an overriding need to get to the destination at any cost. It is as if the option of turning around is not even considered.
One factor that seems to play a significant role in these decisions is an "expectation of success." Pilots develop this ex- pectation of success after encountering adverse conditions on previous flights and successfully completing the trips. The success reinforces taking chances. Since these pilots always have an expectation of success, a back-up plan is never even considered.
Another factor is that these pilots seem to underestimate the increased risk that they face when adverse weather forces them to change their plan. By their very nature, pilots are controllers. They like having things under control. So when the flight is going according to plan, they function very well. However, when the en-route situation changes, things become more chaotic; stress levels rise; and they are out of their comfort zone. Since some pilots don't like to admit having a problem, they look internally for a solution. Instead of realizing that the change in the flight represents a significant change in risk, they venture onward in danger while they seek to work out solutions by themselves. Unfortunately, pilots pressing on into deteriorating weather quickly find themselves painted into a corner, with very few options left.
Because the risks of continued VFR into IMC are so high, the key to preventing these types of accidents is to avoid the situation in the first place. We have seen how these accidents develop, and we touched on the mindset that can lead to risky decisions. Now we will look at how to prevent an accident before it occurs; which factors increase the risk of spatial disorientation; and, finally, what issues you should consider in the preflight and en-route portions of a flight.
The Accident Chain
Safety experts theorize that most accidents result from a chain of errors, not a single mistake. In other words, each event or error forms a link in the accident chain. By themselves, these errors are generally manageable and unrelated, and thus usually go unrecognized. But when combined, in sequence, they can lead to an accident. For example, by itself, pilot fatigue usually won't result in an accident. But it may form one link in an accident chain. If that fatigue is combined with an inoperative gear warning horn and the urgency of an airsick passenger, it's easy to see how the stage is set for a gear-up landing. The key point of the accident chain theory is to teach pilots how to recognize the events that form the links, and then to break the chain before it results in an accident. With this in mind, it's easy to see that trying to avoid the weather by climbing or descending is perhaps an early link in a continued-VFR-into-IMC accident chain.
When VMC Is Really IMC
In some situations, you may find that you need to control the aircraft solely by reference to the flight instruments, even in visual meteorological conditions (VMC). Under these conditions, the risks of spatial disorientation increase greatly. Pilots must know and recognize the factors that create these high-risk environments.
According to the 2000 Nall Report, "Any conditions which deprive the pilot of natural, visual references to maintain orientation, such as clouds, fog, haze, darkness, or terrain/sky backgrounds with indistinct contrast (such as arctic whiteout or clear, moonless skies over water), can rapidly bring about spatial disorientation."
Spatial disorientation could easily occur on a clear moonless night, over water, with visibilities of three to eight miles in haze. And not surprisingly, these were the reported conditions when JFK Jr. descended for Martha's Vineyard.
Another problem at night is that your visual cues may disappear so gradually that you may not notice it happening. Statistics show that the combination of night and IMC create the most deadly general aviation flight environment. Thus, extra vigilance is required.
On the other hand, visual cues and a discernable horizon would be hard to make out flying into the sun over a major metropolitan area, in the late afternoon or evening. The restricted visibility from the haze combined with the sun in your eyes would make controlling the aircraft by visual references difficult at best.
Ironically, in the examples above, if you looked at the just the surface observations (METARs) for the area, they would probably suggest good VFR weather. But flight conditions and surface conditions are two separate issues. Three miles' visibility in haze from a tower controller's point of view is a lot more optimistic than three miles in haze when flying directly into the sun. Don't be fooled.
Preflight Issues
To avoid running into weather surprises on your flight, obtain a thorough weather briefing before you depart. Be alert for conditions that could lead to a high-risk en- vironment. Review your cloud coverage definitions to evaluate the extent of any cloud layers. And remember to ask the specialist for any pilot reports along your route.
Next, make your go/no-go decision based on the information you receive. Remember that the go/no-go decision is a work in progress, and subject to change at any time. You may decide to wait for the weather to improve. Then you can reevaluate the situation. That's a perfectly acceptable decision.
If you do decide to launch, carefully consider your options. Identify suitable alternates along your entire route, not just near the destination. If you are considering a night flight, plan a route with the best outside visual references, even if it lengthens the flight. Plan the flight over lighted towns and cities, instead of over open country, mountains, or water. Finally, determine your personal limitations before you get into the aircraft, and then stick to them.
En Route Issues
Once you have launched, continuously reevaluate the go/no-go decision and your options during the flight. Realize that every flight is a continuing, constant evaluation of the status of the pilot, aircraft, mission, and environment. For example, if you became fatigued, or if a communication radio malfunctioned, that would require a compete reevaluation of the situation. You should consider how your fatigue could affect your performance, or what ramifications the inoperative radio would have on your flight. If you start to feel uncomfortable at any time, break the chain of events by promptly going to your back-up plan.
If you are confronted with adverse weather conditions en route, be decisive. Rather than pressing on, you could circle while considering your options and formulating a plan. Depending on the situation, you could turn around and return to your departure airport. Or, you could proceed to a suitable alternate. Use the "Four C's" memory aid to guide your actions. First, confess to yourself that the situation has changed, and that you must make a new plan. Second, climb to a higher altitude if possible. This will give you better radar and radio coverage and a better view of visual landmarks, and it helps to keep you clear of terrain. Third, conserve fuel by reducing power. Fuel is a resource, and you may need it to make it to your alternate. Fourth, consult with all available resources to replan your flight. This includes communicating with air traffic control or Flight Watch to let them help you. If you don't know the ATC frequency, transmit in the blind on 121.5 MHz. Advise the responding ground station of your situation and ask for radar vectors to the nearest VFR conditions. Prompt action will help to keep an urgent situation from becoming a distress situation.
In any urgent situation it's important to use all available resources. One of the most overlooked resources is the autopilot. Even if it is just a simple wing leveler, it can be invaluable in keeping the aircraft under control in marginal weather conditions. Engage the heading mode and let the autopilot make the 180-degree turn for you. If there are other pilots or passengers on board, request their assistance, perhaps by handling the radios. There is no rule that says you must do everything by yourself. Professional pilots understand this. In a two-pilot airline crew, each pilot's duties are well-defined. The only job of the PF (pilot flying) is to fly the aircraft. The PNF (pilot not flying) handles the radios, navigation, and checklists.
If you do run into trouble and have an in-flight emergency, remember the regulations give the pilot in command the authority to deviate from any rule to the extent required to meet that emergency. If the weather is closing in, it is much safer to make a planned off-airport landing on a road or field than to continue on. No one, not even the FAA, can criticize you for being safe.
Simple Steps
Preventing attempted VFR-into-IMC accidents boils down to just a few simple steps. First, research your options before takeoff, and always have a back-up plan in case the situation changes. Second, recognize that sometimes, VFR can really be IMC. Be aware of the high risk factors that can lead to spatial disorientation. And third, constantly evaluate your options en route. Be committed to maintaining flexibility. If you sense an accident chain starting to form, break it before you run out of options. For the future, invest in an instrument rating - but remember that it does you no good unless you are current and proficient.
Christopher Parker is an active CFI as well as an aviation author, speaker, and FAA remedial training specialist. He also pilots a business jet based in California.
Related Articles
