Killing Zone

In my spare time, I've been reading a book entitled The Killing Zone by Paul Craig. The book's thesis is that pilots whose number of flight hours fall within a particular range are more likely to be involved in fatal accidents that other pilots with more or less experience. The book draws heavily on NTSB reports and statistics, presenting a compelling argument for several types of flying that pilots should treat with a great deal of respect and care, given their level of experience.

According to the Nall Report, an analysis of GA accident data published each year by the Aircraft Owners and Pilots Association's Air Safety Foundation, the popular ways to get into trouble in a small plane are to run out of fuel, attempt to continue VFR flight into deteriorating weather conditions, and low-level maneuvering flight. The highest risk last year was low-level maneuvering flight and the most likely to lead to a fatality was continued flight into deteriorating weather. While it's early in the accident investigation process, it seems that the crash of an SR20 yesterday into a high-rise building on New York's Upper East Side involved the intersection of at least two of these risk factors - low level flight and marginal VFR weather conditions.

Several other factors have been cited that should have helped mitigate the risks of that flight. News stories have latched onto the fact that the SR20 was equipped with an aircraft parachute that could have saved the day. Even if the 'cute had been deployed, it's unclear whether or not the aircraft would have avoided damage or injury to people on the ground during the descent. I think many Cirrus pilots are hesitant to consider pulling that parachute handle because doing so is guaranteed to total the airframe. The parachute is really a last resort when you can no longer fly the plane. Based on witness reports, it appears the pilot and instructor were still trying to fly the plane.

This brings up the second factor that should have made the flight less risky - the report that there was a flight instructor on board. According to the Nall Report, flying with a flight instructor is statistically the safest GA flying you can do. I haven't yet seen an attempt to quantify the instructor's level of experience with the level of safety, but it is my experience is that younger, low-time instructors are hungry. Many of these instructors seem willing to fly in marginal weather since flying is how they earn their meager income and build the flight time required to move on to better paying, more respectable flying. Add to this equation a client who really wants to fly that day and you have the potential for some risky decision making.

The last factor that has been mentioned is the advanced avionics found in Cirrus aircraft, which some say should have prevented the crash. I don't know the vintage of the SR20 involved in the accident, but some of the older SR20s are steam gauge planes and lack many of the advanced features of the later models. And this just in - a glass panel cannot keep a pilot from hitting an obstruction. Used properly, terrain awareness can increase the safety of flight, but it is no guarantee.

After learning of the accident, I did a quick check of the surface weather observations for Tereboro Airport, where the flight originated, for the time period before and after the accident.

KTEB 111551Z 10007KT 060V120 7SM OVC015 17/12 A2994 RMK AO2 SLP139 T01670117
KTEB 111651Z 11007KT 7SM OVC015 17/12 A2993 RMK AO2 SLP133 T01670122
KTEB 111751Z 09007KT 7SM OVC017 17/12 A2990 RMK AO2 SLP125 T01670122 10172 20150 58017
KTEB 111851Z 08007KT 7SM OVC019 17/13 A2987 RMK AO2 SLP115 T01720128
KTEB 111951Z COR 09008KT 3SM DZ OVC019 17/13 A2986 RMK AO2 DZB48 SLP109 P0000 T01720128
KTEB 112031Z 07004KT 2SM RA OVC017 17/13 A2985 RMK AO2 DZE02RAB02 P0005
KTEB 112051Z VRB05KT 2SM -RA OVC019 16/13 A2984 RMK AO2 DZE02RAB02 SLP106 P0010 60010 T01610133 56020

It's too early to know all the details of this particular crash, but it clearly was not a good day to be flying VFR. While the visibly at times was more than 5 miles, the cloud ceiling was never above 2000 feet.

The probability of a technically advanced aircraft with a qualified and appropriately rated flight instructor on board flying into a building at a low altitude in marginal VFR conditions is very, very low, but that probability is not zero. If you think it can't happen to you, think again.