Too Many Weather-Related Plane Crashes

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Sometimes you think it’s your imagination (“Is it my imagination, or have there been a lot of plane crashes recently?”), but that’s not the case this time. The crashes are all too real, and all too recent — and, it would seem, the crashes are weather-related.

Specifically, I’m referring to five in-the-news crashes this week:

  • A crash Tuesday in New Jersey of a small plane onto Interstate 287 that killed all five persons on board. Officials reported the pilot confirmed he was experiencing icing conditions shortly after takeoff. Listening to the tape of the conversation with air traffic control, the pilot reported severe icing (severe icing can quickly overwhelm anti-icing/deicing equipment). It was also reported the plane broke up in mid-air which maybe attributed to airframe failure due to the stress of a spin.
  • A crash Tuesday of a training flight in Denton, Texas ended with one dead and two injured. Occurring at night, weather conditions at the time included very low clouds and visibility from 1/2 to 1/4 mile due to fog. It was noted that the fog was unexpected and not part of the forecast.
  • A crash Monday, also in Texas, killed a family of five from Georgia. Strong thunderstorms across Texas caused the plane to route around storms, but it was reported the plane was flying through rain and lightning at the time.
  • On Monday an NTSB report was released citing weather as a contributing factor in a Mississippi crash that took the lives of a husband and wife in 2010. It was reported that “extreme thunderstorms crossed the plane’s path.”
  • This week the FAA issued rules designed to prevent pilots from flying while fatigued — which can trace its “revived” origins to the crash of Continental Connection 3407 which went down near Buffalo, NY in a snow storm nearly three years ago (“revived” because the NTSB has been working on the fatigue ruling for decades, but the issue stalled prior to the 3407 crash).

The site of Tuesday's crash that killed a family of five in Texas. Was weather to blame? Image: ABC13

It doesn’t take a weatherman to tell you that flying in winter conditions is potentially some of the most dangerous flying that can be done. It’s tough for the big planes with the backing of the airlines, the latest technology and paying passengers to fly in winter weather, but it’s nearly impossible to eliminate the risk for the hobbyist and the general aviation pilot.

Why? Why is winter weather so difficult to fly in and why risk it? The strong contrast between the warm air ahead of a winter cold front and the cold air behind the front can result in areas of poor flying weather that extends hundreds, even thousands of miles, while including stronger thunderstorms, more frequent lightning, heavier rain and snow. No single answer can be applied to either question, but one word can certainly be used to send shivers up the spine of any winter pilot: ice.

But that’s why planes are deiced. And that’s why planes have deicing and anti-icing equipment (deicing equipment will remove icing buildup; anti-icing equipment will prevent ice from forming). Except it’s not that easy. Deicing fluid is expensive and is typically applied just before departure and typically the airlines are first in line. Sometimes, airports run out of the fluid. And, believe it or not, not all planes have deicing and/or anti-icing equipment. In fact — and perhaps not surprisingly so — the smaller the plane the less likely it is to have any deicing equipment. Of the five crashes noted above, four were small planes.

Why is ice so dangerous to a plane? Two reasons: First, weight and second because ice changes the shape of the surfaces of the wing.

Extra weight, as you can imagine, is never good for an airplane — whether it’s baggage or ice. Worse, accumulating ice which adds increasing weight makes the icing situation deteriorate quickly requiring immediate corrective action from the pilot. Without action from the pilot or without an improvement in conditions, the ice will eventually make the craft too heavy to fly; its engine will be overpowered and it will fall from the sky like an ice-covered rock. It seems this is what happened in New Jersey on Tuesday.

News choppers cover the site of the crash that took the lives of five in New Jersey. Was weather to blame? Image: NBCNewYork

Equally critical is the changing of the shape of the wing and/or control surfaces by accumulating ice. Wings, of course, are not randomly shaped objects. Though seemingly simple in design, the aircraft wing is anything but simple: even the smallest amount of ice can have a detrimental effect. Such an example is easy to find. Visit your local airfield during the early morning hours near sunrise on a cold, crisp morning and inspect the exposed surfaces of the aircraft left outside overnight and you’ll likely find accumulated ice on exposed aircraft surfaces. Even without the obvious conditions of freezing rain or snow, overnight frost can be enough to ground an aircraft. Fortunately, this type of thin ice melts quickly in the sun and the seasoned pilot of a small plane knows to wait it out with another cup of coffee.

Meteorologically, the mechanical processes that form icing conditions are mostly the same when considering winter vs. summer weather systems. Winter or summer, the typical frontal system will contain ice and icing conditions. However, what’s critically different is the altitude at which ice will form. Even a small plane encountering icing at 10,000 feet can descend and usually recover from all but severe icing. At 600 feet that same amount of icing can become a life and death situation as there just isn’t the needed “cushion” of recovery altitude nor the needed layer of (hopefully) warmer air below to melt the ice.

Icing severity is influenced by criteria such as the intensity of the rain, the size of the water droplets, the density of the clouds and, of course, the air temperature. Even without precipitation, aircraft can experience icing while flying in clouds. Clouds after all, are merely suspended water droplets and, in many cases those water droplets are supercooled. By the way, large, supercooled droplets can lead to dramatic icing faster than you can push over a snowman.

Deicing an airliner is effective, however it's expensive and must be accomplished just before departure. Photo: Wikipedia

As if that’s not bad enough, icing build-up will vary from aircraft to aircraft. In the same meteorological conditions five different aircraft can experience five different types of icing. The shape and size of the wing, the speed of the aircraft and the type of de-icing equipment (or lack of de-icing equipment) all determine the intensity and rate of build-up of ice.

A good friend of mine is a private pilot today and a former  Air Force fighter pilot. He told me, “I’ve conducted in-flight artificial icing tests at EDW [Edwards Air Force Base] and have seen how fast ice can acrete in severe conditions:  30 seconds at 250 knots true air speed will get you six to 10 inches in a double-horned formation on a high performance wing.  A clean 2×12 board would have more lift than a wing carrying that much ice.”

What’s a pilot to do? Not fly, is the easy answer. At the beginning of this article I mentioned aircraft standing in line for a turn at the de-icing station. That’s typically not where the general aviation pilot, especially the private pilot, will be found. Most GA pilots without paying passengers know that if the plane needs de-icing before departure, it’s perhaps a good idea to cancel the flight. Instead, most pilots of small planes find themselves in an icing situation when transitioning through a frontal system. By that time, they’re either at cruise altitude or descending/ascending into icing conditions. Either way, icing is typically a surprise or much worse than expected. What happens next is solely up to the pilot. We have only to look at this week’s headlines to see five wrong decisions.

Fortunately, there are other options than not flying. First is a weather briefing from an aviation meteorologist. Experienced with the specific conditions peculiar to flying, the aviation meteorologist will brief the pilot on flight weather conditions including thunderstorms, turbulence and icing. Second, be familiar with meteorology basics. With or without a weather briefing, a pilot should be able to look at a weather map and pick out regions that may be susceptible to icing and other flight weather hazards. Third, know your aircraft — know its limitations, its strengths and its equipment. Does it have anti-icing and/or deicing equipment? Do you know how (and when) to use it? Fourth, know yourself and objectively know your experience and skill level.  Fifth, be aware of false confidence — always assume the worst and then be pleasantly surprised when it works out better than you hoped. Sixth, be ready and willing to cancel or delay your flight.

How high is the risk when flying in winter weather? Most of the time flying in the winter carries the same risk as flying in the summer. However, there are times when the risk is extremely high. Is weather to blame for the five crashes in the news this week, or are the decisions made by these pilots the root cause of the crash? It will take time for the investigations to run their cycle, but when a private pilot in a small airplane is put against a winter storm front, there are just so many things that can go wrong. It is ultimately up to the pilot to make the final go/no-go decision, but the right decision never makes headlines.

Finally, here’s some good news for anyone boarding a plane this holiday season: Flying on U.S. airlines has become so safe that experts increasingly believe the biggest remaining risk of an accident is when the wheels are on the ground.

ImpactWeather’s YourWeatherBlog has articles written previously about ice and icing. You can visit those articles here, here and here.

Universal Weather and Aviation produces “Aviation Weather Today,” a daily video serious in three segments (North America, North Atlantic, Europe) that details flight weather hazards for the pilot. Hosted by aviation meteorologists Lauren Whisenhunt and myself, these videos are used by pilots and aircrews to help determine where weather hazards will be along their route of flight. Visit www.awt.aero to view these videos.

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