Letters to the Editors
Helicopter Emergency Medical Services and Weather-Related Accidents Editors’ Note: This is an open letter to the readership, and your feedback is requested. Dear Editors: Many organizations are looking at ways to help make the helicopter emergency medical services (HEMS) safer. The Federal Aviation Administration (FAA) is working with federal aviation regulation (FAR) part 135 operators along with organizations such as Helicopter Association International, CAMTS, and AAMS to bring in voluntary solutions. One simple solution to help alleviate many of the night HEMS controlled flight into terrain accidents is by changing the night visual flight rule visibility minimums for FAR part 135 HEMS operations. But what should they be changed to? To help determine that answer, let us first look at the root cause of many of our fatal HEMS accidents since January 2000. To find all of the HEMS accidents on the National Transportation Safety Board (NTSB) Web site (http://ntsb.gov/ntsb/query.asp) takes more than a simple search. Although many of the HEMS accidents were conducted under FAR part 135, others were conducted under FAR part 91. Therefore, finding as many accidents as possible required a search by aircraft type and operator. My search of the NTSB accident Web site resulted in finding 157 HEMS
accidents since January 2000 (Fig. 1); 47 of these were fatal, which equates to a 30% accident fatality rate in the HEMS industry, a rate that is just too high. Of the 47 fatal accidents (Fig. 2), weather was a contributing factor in 22 of the accidents (or 47%). Reading the NTSB reports, it is easy to see that there is a direct correlation between unaided night flights and weather, but is there a prominent factor? Yes; in 73% (16/22) of the weather-related fatal accidents, the temperature and dew point were within 6°F, and the winds were less that 10 knots for the area where the flight was conducted. When those factors are present, there is a high likelihood of fog forming. Add in night unaided operations over a sparsely populated area, and it is unlikely that the fog will be seen by the HEMS crews before it is a problem. To help address the weather-related accident issue, the FAA has implemented changes to A021 by requiring slight increases to the FAR part 135 weather planning minimums and new documentation of our route planning. Most HEMS pilots have been doing this type of detailed flight planning for years but not documenting it. Is it enough? Many of the night HEMS accidents happened with weather considered “legal” when the crew took off, but to understand what is legal, we first need a short class on legal weather. Reported visibility is straightforward; it is what it is. A ceiling
Figure 1. HEMS accidents, 2000-present.
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Figure 2. HEMS fatal accidents, January 2000-present.
is defined in the Aeronautical Information Manual as “the heights above the earth’s surface of the lowest layer of clouds or obscuring phenomena that is reported as ‘broken,’ ‘overcast,’ or ‘obscuration,’ and not classified as ‘thin’ or ‘partial” (http://www.faa.gov/air_traffic/publications/atpubs/PCG/ C.HTM). Any cloud layer reported as few or scattered is not considered a ceiling. Reviewing one of the many HEMS night unaided weatherrelated accidents, the weather report at the time of the accident was winds 290º at 5 knots, 5-mile visibility, few clouds at 500 feet, overcast at 5,500 feet, temperature ⫹21, and dew point ⫹20. This was “legal” weather for the flight, with the few clouds at 500 feet not even factoring into the weather equation because few clouds do not constitute a ceiling; however, they still crashed with legal weather. So, can we change the weather minimums to something reasonable that could help reduce the weather-related fatal crashes in the HEMS community? To help reduce the weather-related fatal HEMS crashes, I propose changing the current FAR part 135 in route weather requirements by adding the following: night cross-country operations without night vision imaging systems require visibility of not less than 5 miles with no cloud or obscuring phenomena layers below 2,000 feet. This simple and straightforward 2,000/5 is an easy solution that could help protect our unaided HEMS crews, and this more restrictive weather minimum would only be a real factor when there is a high probability of fog; in 16 of the 22 fatal HEMS accidents or 73% of those fatal incidents, weather was a contributing factor, and there was a high probability of fog or low clouds in the area. The amount of HEMS accidents our industry has seen cannot continue. Many times when looking for ways to prevent May-June 2014
accidents, we find complex and time-consuming solutions. But, if we bring all interested parties to the table and look at the root cause of most accidents, we can normally find a simple solution to rectify the problem. Pilots, operators, professional organizations, the FAA, and the NTSB need to continue to work together to find a solution before more HEMS professionals are lost. Bryan Butler, BS, PHI Air Medical LLC, Sierra Vista, AZ Reprinted with permission from Rotorcraft Pro Magazine
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Helicopter Emergency Medical Services and Weather-Related Accidents Editors’ Note: This is an open letter to the readership, and your feedback is requested. Dear Editors: Many organizations are looking at ways to help make the helicopter emergency medical services (HEMS) safer. The Federal Aviation Administration (FAA) is working with federal aviation regulation (FAR) part 135 operators along with organizations such as Helicopter Association International, CAMTS, and AAMS to bring in voluntary solutions. One simple solution to help alleviate many of the night HEMS controlled flight into terrain accidents is by changing the night visual flight rule visibility minimums for FAR part 135 HEMS operations. But what should they be changed to? To help determine that answer, let us first look at the root cause of many of our fatal HEMS accidents since January 2000. To find all of the HEMS accidents on the National Transportation Safety Board (NTSB) Web site (http://ntsb.gov/ntsb/query.asp) takes more than a simple search. Although many of the HEMS accidents were conducted under FAR part 135, others were conducted under FAR part 91. Therefore, finding as many accidents as possible required a search by aircraft type and operator. My search of the NTSB accident Web site resulted in finding 157 HEMS
accidents since January 2000 (Fig. 1); 47 of these were fatal, which equates to a 30% accident fatality rate in the HEMS industry, a rate that is just too high. Of the 47 fatal accidents (Fig. 2), weather was a contributing factor in 22 of the accidents (or 47%). Reading the NTSB reports, it is easy to see that there is a direct correlation between unaided night flights and weather, but is there a prominent factor? Yes; in 73% (16/22) of the weather-related fatal accidents, the temperature and dew point were within 6°F, and the winds were less that 10 knots for the area where the flight was conducted. When those factors are present, there is a high likelihood of fog forming. Add in night unaided operations over a sparsely populated area, and it is unlikely that the fog will be seen by the HEMS crews before it is a problem. To help address the weather-related accident issue, the FAA has implemented changes to A021 by requiring slight increases to the FAR part 135 weather planning minimums and new documentation of our route planning. Most HEMS pilots have been doing this type of detailed flight planning for years but not documenting it. Is it enough? Many of the night HEMS accidents happened with weather considered “legal” when the crew took off, but to understand what is legal, we first need a short class on legal weather. Reported visibility is straightforward; it is what it is. A ceiling
Figure 1. HEMS accidents, 2000-present.
84
Air Medical Journal 33:3
Figure 2. HEMS fatal accidents, January 2000-present.
is defined in the Aeronautical Information Manual as “the heights above the earth’s surface of the lowest layer of clouds or obscuring phenomena that is reported as ‘broken,’ ‘overcast,’ or ‘obscuration,’ and not classified as ‘thin’ or ‘partial” (http://www.faa.gov/air_traffic/publications/atpubs/PCG/ C.HTM). Any cloud layer reported as few or scattered is not considered a ceiling. Reviewing one of the many HEMS night unaided weatherrelated accidents, the weather report at the time of the accident was winds 290º at 5 knots, 5-mile visibility, few clouds at 500 feet, overcast at 5,500 feet, temperature ⫹21, and dew point ⫹20. This was “legal” weather for the flight, with the few clouds at 500 feet not even factoring into the weather equation because few clouds do not constitute a ceiling; however, they still crashed with legal weather. So, can we change the weather minimums to something reasonable that could help reduce the weather-related fatal crashes in the HEMS community? To help reduce the weather-related fatal HEMS crashes, I propose changing the current FAR part 135 in route weather requirements by adding the following: night cross-country operations without night vision imaging systems require visibility of not less than 5 miles with no cloud or obscuring phenomena layers below 2,000 feet. This simple and straightforward 2,000/5 is an easy solution that could help protect our unaided HEMS crews, and this more restrictive weather minimum would only be a real factor when there is a high probability of fog; in 16 of the 22 fatal HEMS accidents or 73% of those fatal incidents, weather was a contributing factor, and there was a high probability of fog or low clouds in the area. The amount of HEMS accidents our industry has seen cannot continue. Many times when looking for ways to prevent May-June 2014
accidents, we find complex and time-consuming solutions. But, if we bring all interested parties to the table and look at the root cause of most accidents, we can normally find a simple solution to rectify the problem. Pilots, operators, professional organizations, the FAA, and the NTSB need to continue to work together to find a solution before more HEMS professionals are lost. Bryan Butler, BS, PHI Air Medical LLC, Sierra Vista, AZ Reprinted with permission from Rotorcraft Pro Magazine
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