- Email: [email protected]
Weather Webcam System for the Safety of Helicopter Emergency Medical Services in Miyazaki, Japan
Air Medical Journal 36 (2017) 71e76
Contents lists available at ScienceDirect
Air Medical Journal journal homepage: http://www.airmedicaljournal.com/
Original Research
Weather Webcam System for the Safety of Helicopter Emergency Medical Services in Miyazaki, Japan Katsuhiro Kanemaru, MD 1, Robert Katzer, MD, MBA 2, Syu Hanato 3, Koji Nakamura 3, Hiroshi Matsuoka, MD 1, Hidenobu Ochiai, MD, PhD 1 1 2 3
Emergency Medicine, Acute Critical Care Center, University of Miyazaki Hospital, Miyazaki, Japan Department of Emergency Medicine, UC Irvine, Orange, CA NishiNippon Airlines, Fukuoka, Japan
a b s t r a c t Objective: In Japan, the helicopter emergency medical services (HEMS) system was initiated in 2001 and introduced to Miyazaki Prefecture in 2012. Mountainous areas occupy 88% of Miyazaki’s land area, and HEMS flights can be subject to the effects of weather. Therefore, ensuring safety in changing weather conditions is a necessity for HEMS. Methods: The weather webcam system (WWS) was established to observe the meteorological conditions in 29 locations. Assessments of the probability of a flight based on conventional data including a weather chart provided by the Japan Meteorological Agency and meteorological reports provided by the Miyazaki Airport were compared with the assessment based on the combination of the information obtained from the WWS and the conventional data. Results: The results showed that the probability of a flight by HEMS increased when using the WSS, leading to an increased transportation opportunity for patients in the mountains who rely on HEMS. In addition, the results indicate that the WWS may prevent flights in unfavorable weather conditions. Conclusion: The WWS used in conjunction with conventional weather data within Miyazaki HEMS increased the pilot’s awareness of current weather conditions throughout the Prefecture, increasing the probability of accepting a flight. Copyright © 2017 by Air Medical Journal Associates
Emergency care using civilian helicopter emergency medical services (HEMS) was initiated in several locations including the United States and countries in Europe around 1970.1,2 It has spread throughout Europe, the United States, and Canada and is frequently used for prehospital emergency medical care at the scene of an incident and for the interfacility transfer of severely ill or injured patients. As a result, HEMS is an important component of emergency medical services. However, fatal helicopter crashes occur, and finding ways to ensure operational safety is essential to the industry.3 HEMS was initiated by the Japanese government in 2001, with the goal of deploying 1 helicopter in each prefecture. It is commonly referred to as “Doctor-Heli” because a pilot and a mechanic are on board as the operation crew, and an emergency medicine physician and nurse are on board as the medical crew. It is usually dispatched via a request from the fire department. Similar to HEMS systems in other countries, it is frequently used for prehospital emergency medical care at the incident scene and for interfacility transfer of E-mail address: [email protected] (K. Kanemaru). 1067-991X/$36.00 Copyright © 2017 by Air Medical Journal Associates http://dx.doi.org/10.1016/j.amj.2017.01.008
severely ill or injured patients.4-7 Although the history of HEMS in Japan is relatively short, the efficacy of its activities has been reported.8-12 The total number of dispatches of the Japanese HEMS system between 2001 and 2014 exceeded 100,000. Fortunately, no fatal accidents have occurred in the Japanese system.6 However, ensuring the safety of HEMS is always a concern. In Japan, steep mountain ranges run through the center of the country from north to south, with the mountainous regions occupying 61% of its land area.13 In addition, because only visual flight rules (VFRs) have been used for HEMS flights in Japan, both weather and geographic conditions are major factors in the ability to fly. In fact, in the 1990s, 3 crashes of commercial helicopters in Japan occurred because of bad weather, and a total of 24 people perished. Comparing the extent of mountainous districts in Japan to other countries, Germany has almost the same land area as Japan, but the mountainous areas account for only approximately 33%. In the United Kingdom, mountainous areas occupy only approximately 15% of the total area.14 Therefore, Japan’s topography demands
72
K. Kanemaru et al. / Air Medical Journal 36 (2017) 71e76
unique consideration in terms of both weather data collection and consideration of weather minimums. In Miyazaki Prefecture, Doctor-Heli was established at the University of Miyazaki Hospital in 2012.15 Its mountainous district accounts for 88% of the total 7,736 km2 area, and 425,000 (37.4%) of its 1,137,000 residents live in these mountainous areas.16 There are few medical facilities in the mountainous areas. As a result of this, ground transport emergency medical service times to medical facilities are often prolonged. Therefore, the capabilities of HEMS in the mountains are very important, and the ability to dispatch Doctor-Heli may be associated with decreased morbidity and mortality of these patients. However, the use of HEMS in the mountains is dependent on weather conditions, and the ability to understand current weather conditions may prevent launching the aircraft to an area experiencing conditions below weather minimums. Ensuring safe helicopter operations in this region has been a particular organizational focus. As a tool to address this challenge, we established the weather webcam system (WWS). This system supplements the pilots’ standard weather report by providing direct views of 29 locations, increasing the available real-time information at the helibase. The cost to maintain this system (approximately $13,500 a year, calculated based on the rate of exchange of $1 ¼ 120 yen) is funded by the Miyazaki Prefectural government. This is the first study evaluating the use of a WWS in HEMS flight safety. This study aims to describe WWS and determine how much the WWS information can contribute to a pilot's decision making regarding current flight conditions. Materials and Methods HEMS in Miyazaki In Miyazaki, HEMS operates solely under VFRs, as with HEMS in other regions in Japan. Additionally, VFR operation is not permitted at night according to Japanese regulations. Consequently, there are no night HEMS flights. The number of HEMS requests has increased year after year and has reached 1,295 cases in the 3 years since the start of 2012. The paramedics and firefighters responding to the scene of a medical emergency anywhere in Miyazaki determine the need for and request HEMS. The pilot determines whether to accept a dispatch request by evaluating a weather map, the Aerodrome routine meteorological report, the terminal forecast, and 9 weather webcams installed by a commercial weather research company. These existing cameras were mostly positioned to evaluate road conditions. However, these locations do not necessarily accurately reflect the current weather conditions in the different mountainous areas that account for 88% of Miyazaki’s land area. As a result, dispatched flights were often aborted en route as a result of visibility and ceiling under VFRs in mountainous areas after launch. In the case of borderline weather at or en route to the scene, if the pilot makes the determination to launch and attempt the flight, the aircraft will do so with the pilot, mechanic, nurse, and physician aboard. In the case of deteriorating weather while en route to the hospital, the aircrew has several options. Often, the cloud ceiling allows them to fly a wider path around the mountains and along the coast at a lower altitude. If it is not possible to fly to the original destination hospital, the aircraft may divert to an alternative hospital that has a heliport, divert to an airport, or divert to 1 of more than 400 designated landing zones in the prefecture in order to rendezvous with a paramedic ambulance. The physician and nurse will then accompany the patient in the ambulance to the destination hospital. In the event that a request for dispatch arrives nearing sunset, the pilot evaluates the flight duration to the scene, destination hospital, and heliport in the event that the destination hospital is not the University of Miyazaki. If the pilot believes there will not be
sufficient daylight, the dispatch is canceled before launch. The physician and nurse have the opportunity to use the “doctor car” to respond to dispatches that occur during nighttime or during poor weather conditions and transport the patient aboard a fire department ambulance. WWS The weather webcams were installed in 20 spots chosen by the pilots as good indicators for the weather conditions of the different mountainous areas (Fig. 1). The images from these webcams were combined with the images obtained from the 9 weather webcams that were already installed by a commercial weather research company. In this system, the images from a total of 29 webcams were checked visually on the desktop screen to estimate the real-time meteorological conditions (Fig. 2). Specifically, to best address those conditions pertinent to weather minimums including the visibility and cloud ceiling, the weather webcams were installed at locations where the ridgeline of the mountains could be viewed widely and the weather conditions in the valleys could be confirmed. It is possible to share these meteorological conditions along the flight path with all the crewmembers as well as the pilot before launching. In addition, the communication specialists monitor the images obtained from the weather webcams when the aircraft is in flight and can inform the helicopter of the meteorological changes on the flight path via radio. Data Collection To determine the benefits of the WWS in rating weather suitability for the dispatch of a flight, an assessment based on conventional data, including the weather chart provided by the Japan Meteorological Agency and the meteorological reports (eg, the Aerodrome routine meteorological report and the terminal forecast) provided by the Miyazaki Airport (WWS), was compared with the assessment based on the information obtained from the WWS combined with the conventional data (WWSþ). Under the WWS, the pilots obtain weather conditions at the airport including type, amount, height, and location of clouds; wind direction and speed; and temperature. The pilots then use this information to estimate if the minimum cloud ceiling and visibility are likely present in the mountains. The WWS also allows the pilots to visualize many mountain ridge lines directly to evaluate cloud ceilings and visibility. The survey period was defined as approximately 6 weeks between June 26 and August 6, 2014. This period was defined as the survey period because it was during the rainy season in Japan, and the weather forecast in the mountains was especially severe during this period. The survey was performed for 26 locations within the prefecture at 8:00, 12:00, and 18:00 each day. The HEMS pilots who worked on the survey days estimated the flight dispatch probability according to the WWS and WWSþ using a scale of 1 to 4 where 1 indicates there is a 100% probability of flight, 2 the flight is probable, 3 the flight is not probable, and 4 the flight is not possible. A total of 2 pilots participated in the survey as a result of their shift schedule. Results Using WWS and WWSþ weather data sources, the weather suitability of 26 different areas was assessed at 8:00, 12:00, and 18:00 each day over a period of 42 days. Of the 3,276 weather suitability assessments, the flight probability differed between WWS and WWSþ 429 times (13.1%). Of these 429 measurements, there were 277 instances (64.6%) in which the assessment of the flight probability with the WWSþ was higher than with the WWS. In 177 of those instances, the flight probability in WWSþ was 1. In contrast, there were 152 times (35.4%) when the assessment of the flight probability in the WWSþ was lower than the WWS. In 86 of those assessments, the flight probability in WWSþ was 4 (Fig. 3).
K. Kanemaru et al. / Air Medical Journal 36 (2017) 71e76
73
Figure 1. The location of Miyazaki Prefecture and the installation site of the weather webcams.
Figure 2. The display screen of the WWS.
The area of the prefecture demonstrating the greatest difference in assessment between WWS and WWSþ was Shiiba Village with 35 (27.8%) out of 126 assessments in disagreement (Fig. 4). The top 3 areas that showed differences in the assessment had differences
nearly twice as great as the mean. These 3 areas were located in areas surrounded by steep mountains. In 49 out of 58 cases when HEMS was requested during the survey period, HEMS was dispatched. Three cases were canceled as a result of the pilot’s weather
74
K. Kanemaru et al. / Air Medical Journal 36 (2017) 71e76
Figure 3. Flight probability assessments comparing WWS and WWSþ.
assessment using the WWS. The remaining 6 were canceled as a result of insufficient daylight. Discussion This study showed that the information provided by the WWS affected the pilot assessment of the flight dispatch probability compared with the use of conventional forecasting tools. In fatal accidents involving HEMS, weather is often a factor. In a report analyzing the causes of accidents within HEMS in the United States, “A Safety Review and Risk Assessment in Air Medical Transport”17 by the Air Medical Physician Association, an introductory statement indicates that “an accident due to a single independent cause is rare.” The report also states that “pilot error was attributed as the direct or indirect cause of HEMS accidents approximately three times more often than mechanical failure; of the pilot errors, onethird were weather related.” In addition, Thies et al,18 who examined the causes of accidents in HEMS in Germany, described that 25 of 27 accidents were associated with “pilot error” and reported that “flying at low altitude under bad weather conditions is another important factor contributing to accidents.” According to an analysis of the weather and the causes of accidents, it was reported that the risk of death increased 8 times when HEMS was dispatched under bad weather conditions.19 As a step to prevent weather-related accidents, the US Federal Aviation Administration recommended the preflight risk assessment score (PRAS) in 2005. In the PRAS, the flight risk factors (pilot experience, weather, night vs. daytime operations, local vs. nonlocal flight, familiar vs. unfamiliar terrain, fatigue factors, and knowledge from a prior pilot cancellations of the same transport) were scored; the higher the points, the greater the flight risk.20 However, this assessment method has more limited usefulness for HEMS in Japan because no flights are performed at night. Furthermore, it has been reported that the usefulness of the PRAS under bad weather conditions is uncertain.21 In an effort to ensure safe flight operations during the initiation of HEMS, the Japan Transport Safety Board recommended the following 5 items in 1997: 1) recognize the importance of weather judgment in VFR operations; 2) establish a system that can provide the weather conditions along the flight path to the pilot; 3) use policy, such as returning immediately when the weather worsens; 4) fly at a minimum altitude; and 5) try to ensure that the pilot can perform instrument flight in the event of emergency resulting from deteriorating weather conditions.
We established the original WWS for the purpose of ensuring safety under variable weather conditions in the HEMS system in Miyazaki. There were differences in the assessment of flight conditions in 429 instances (13.1%) between the WWSþ and WWS. From these results, it can be concluded that the WWS is a system with information that consistently influences the assessment of the flight conditions and suitability for flight in at least 3 of 26 areas. In addition, a more favorable assessment of flight conditions was shown 277 times and a less favorable one was shown 152 times in the WWSþ in comparison with the WWS. This indicated that WWS provided additional operational weather assessment data compared with traditional weather information alone. These results indicated that the meteorological forecast based on WWS was relatively limited and tended to decrease the flight probability of the pilots’ assessment when compared with WWSþ. In other words, it was suggested that the probability of a safe flight could not be assessed consistently based on WWS. The flight probability was assessed as less than 1 in the WWS and was assessed as 1 in WWSþ 177 times. This indicated that the predicted probability of a flight by HEMS might increase when using the WSS. This may lead to a larger number of accepted dispatches, providing HEMS capability for more patients in the mountains who rely on it. Conversely, flight probability was assessed as 1, 2, or 3 based on WWS but assessed as 4 86 times based on WWSþ, indicating that the WWS may prevent dispatching the aircraft under unsuitable weather conditions. Based on the findings in this survey and after reviewing the recommendations by the Japan Transport Safety Board, the recommendations can be restated as follows: 1) the WWS is a system that allows all HEMS crewmembers to assess and share important weather conditions on a screen, 2) the WWS is a system that can provide weather information along the flight path to the pilot before dispatch, and 3) the WWS is a system that enables immediate stand-down conditions via radio when worsening weather is detected on the images by the weather webcams. Therefore, WWS alone meets 3 of the 5 recommendations. There have been no fatal accidents since HEMS began in Japan in 2001 using the following flight methods as safety measures: taking off and landing at predetermined landing zones, the use of twin engines (helicopter models AW109SP, Bell429, BK117, EC135, and MD902), flights limited to daytime, and flights requiring 1 pilot and 1 mechanic on board.6 The WWS, which was established to increase the pilots' views, was an example of 1 way of enhancing safety by augmenting weather information.
K. Kanemaru et al. / Air Medical Journal 36 (2017) 71e76
75
Figure 4. Three areas with the greatest difference between WWS and WWSþ.
One potential limitation of this study is the possibility that the results were exaggerated as a result of the rainy season. Performing the survey of WWS for a 1-year period may be necessary to establish this. In addition, the pilot’s judgment of the flight probability using WWS was based on no standard rules beyond the perceived visibility and cloud ceiling on the screen. An assessment of the WWS based on more standardized criteria or linked to a form of automated weather observing station may be required in the future.22 Because HEMS in Japan operates during daylight only, these results may not necessarily apply to night operations. Finally, in this study, the flight probability was estimated 3 times a day regardless of whether a dispatch was requested. The ideal assessment of the usefulness of the WWS would be the assessment of flight probability by the WWS and WWSþ upon receipt of a dispatch request and the comparison of its probability with the actual flight probability. Conclusion Japan has significant areas of mountainous terrain that are characteristically susceptible to bad weather. In the past, crashes of commercial helicopters occurred because of bad weather. The nation also restricts nighttime VFR operations in an effort to prevent crashes from low visibility conditions. Considering these facts, we established the WWS for the purpose of safe HEMS operations within the Miyazaki Prefecture. This system allows aircrew to visually evaluate the weather along the flight path before a flight, which greatly helps pilots to judge the flight probability. The WWS provides crucial weather condition information about the
mountainous portions of the Miyazaki Prefecture, contributing to safe HEMS operations and helping to maintain the record of no fatal collisions in the HEMS system. References 1. Hinkelbein J, Schwalbe M, Neuhaus C, et al. Incidents, accidents and fatalities in 40 years of German helicopter emergency medical system operations. Eur J Anaesthesiol. 2011;28:766e773. 2. McGinnis K, Judge T, Nemitz B, et al. Air Medical Services: future development as an integrated component of the Emergency Medical Services (EMS) System: a guidance document by the Air Medical Task Force of the National Association of State EMS Officials, National Association of EMS Physicians, Association of Air Medical Services. Prehosp Emerg Care. 2007;11:353e368. 3. Butler B. Helicopter emergency medical services and weather-related accidents. Air Med J. 2014;33:84e85. 4. Mashiko K, Matsumoto H, Hara Y, Yagi T. Realising the potential : challenges and opportunities for HEMS in Japan. AirRescue. 2013;3:124e126. 5. Nishikawa W, Yamano Y. An overview of the development of helicopter emergency medical services in Japan. Air Med J. 2010;29:288e291. 6. Nishikawa W, Yamano Y. HEMS flight safety. http://airmed.eu/pdfs/P_04_ Nishikawa.pdf. Accessed July 5, 2016. 7. Matsumoto H, Kanemaru K, Hara Y, et al. Development of an educational program for the helicopter emergency medical services in Japan. Air Med J. 2013;32:84e87. 8. Abe T, Takahashi O, Saitoh D, Tokuda Y. Association between helicopter with physician versus ground emergency medical services and survival of adults with major trauma in Japan. Crit Care. 2014;18:R146. 9. Yamaguchi T, Mashiko K, Sakamoto Y, et al. Comparison between helicopter emergency medical service and ambulance transportation to rescue people injured by traffic crashes in Japan. Prehosp Disaster Med. 2007;22:31e33. 10. Hata N, Kobayashi N, Imaizumi T, et al. Use of an air ambulance system improves time to treatment of patients with acute myocardial infarction. Intern Med. 2006;45:45e50. 11. Matsumoto H, Mashiko K, Hara Y. Effectiveness of a “doctor- helicopter” system in Japan. Isr Med Assoc J. 2006;8:8e11.
76
K. Kanemaru et al. / Air Medical Journal 36 (2017) 71e76
12. Hata N, Shinada T, Kobayashi N, et al. Severity of cardiovascular disease patients transported by air ambulance. Air Med J. 2011;30:328e332. 13. 1e8 area by configuration, gradient, and prefecture. Japanese Statistical Year Book 2016 [in Japanese]. http://www.stat.go.jp/data/nenkan/01.htm. Accessed July 29, 2016. 14. The vulnerability of a nation. Ministry of Land, Infrastructure, Transport and Tourism [in Japanese]. http://www.mlit.go.jp/common/000997376.pdf. Accessed July 29, 2016. 15. Katzer RJ. Japanese Prefecture integrates physician staffed medical helicopter into regional EMS system. http://www.emergency-live.com/en/news/japaneseprefecture-integrates-physician-staffed-medical-helicopter-into-regional-ems-system/. Accessed June 26, 2016. 16. Miyazaki Mountainous Areas Promotion Plan. July 2015 [in Japanese]. http:// www.pref.miyazaki.lg.jp/chusankan-chiiki/kense/kekaku/20150711094913.html. Accessed July 29, 2016.
17. Blumen IJ, Coto J, Maddow CL, et al. A safety review and risk assessment in air medical transport. Air Medical Physician Handbook. Salt Lake City, UT: The Air Medical Physician Association; 2002:53e55. 18. Thies KC, Sep D, Derksen R. How safe are HEMS-programmes in Germany? A retrospective analysis. Resuscitation. 2006;68:359e363. 19. Baker SP, Grabowski JG, Dodd RS, Shanahan DF, Lamb MW, Li GH. EMS helicopter crashes: what influences fatal outcome? Ann Emerg Med. 2006;47: 351e356. 20. Winn W, Thomas F, Johnson K. Strategies to reduce US HEMS accidents. Air Med J. 2012;31:78e83. 21. Thomas F, Groke S, Handrahan D. Intermountain life flight preflight risk assessment score and transport outcomes. Air Med J. 2011;30:49e50. 22. Automated Surface Observing Syste (ASOS). https://www.ncdc.noaa.gov/dataaccess/land-based-station-data/land-based-datasets/automated-surface-observingsystem-asos. Accessed December 20, 2016.
Contents lists available at ScienceDirect
Air Medical Journal journal homepage: http://www.airmedicaljournal.com/
Original Research
Weather Webcam System for the Safety of Helicopter Emergency Medical Services in Miyazaki, Japan Katsuhiro Kanemaru, MD 1, Robert Katzer, MD, MBA 2, Syu Hanato 3, Koji Nakamura 3, Hiroshi Matsuoka, MD 1, Hidenobu Ochiai, MD, PhD 1 1 2 3
Emergency Medicine, Acute Critical Care Center, University of Miyazaki Hospital, Miyazaki, Japan Department of Emergency Medicine, UC Irvine, Orange, CA NishiNippon Airlines, Fukuoka, Japan
a b s t r a c t Objective: In Japan, the helicopter emergency medical services (HEMS) system was initiated in 2001 and introduced to Miyazaki Prefecture in 2012. Mountainous areas occupy 88% of Miyazaki’s land area, and HEMS flights can be subject to the effects of weather. Therefore, ensuring safety in changing weather conditions is a necessity for HEMS. Methods: The weather webcam system (WWS) was established to observe the meteorological conditions in 29 locations. Assessments of the probability of a flight based on conventional data including a weather chart provided by the Japan Meteorological Agency and meteorological reports provided by the Miyazaki Airport were compared with the assessment based on the combination of the information obtained from the WWS and the conventional data. Results: The results showed that the probability of a flight by HEMS increased when using the WSS, leading to an increased transportation opportunity for patients in the mountains who rely on HEMS. In addition, the results indicate that the WWS may prevent flights in unfavorable weather conditions. Conclusion: The WWS used in conjunction with conventional weather data within Miyazaki HEMS increased the pilot’s awareness of current weather conditions throughout the Prefecture, increasing the probability of accepting a flight. Copyright © 2017 by Air Medical Journal Associates
Emergency care using civilian helicopter emergency medical services (HEMS) was initiated in several locations including the United States and countries in Europe around 1970.1,2 It has spread throughout Europe, the United States, and Canada and is frequently used for prehospital emergency medical care at the scene of an incident and for the interfacility transfer of severely ill or injured patients. As a result, HEMS is an important component of emergency medical services. However, fatal helicopter crashes occur, and finding ways to ensure operational safety is essential to the industry.3 HEMS was initiated by the Japanese government in 2001, with the goal of deploying 1 helicopter in each prefecture. It is commonly referred to as “Doctor-Heli” because a pilot and a mechanic are on board as the operation crew, and an emergency medicine physician and nurse are on board as the medical crew. It is usually dispatched via a request from the fire department. Similar to HEMS systems in other countries, it is frequently used for prehospital emergency medical care at the incident scene and for interfacility transfer of E-mail address: [email protected] (K. Kanemaru). 1067-991X/$36.00 Copyright © 2017 by Air Medical Journal Associates http://dx.doi.org/10.1016/j.amj.2017.01.008
severely ill or injured patients.4-7 Although the history of HEMS in Japan is relatively short, the efficacy of its activities has been reported.8-12 The total number of dispatches of the Japanese HEMS system between 2001 and 2014 exceeded 100,000. Fortunately, no fatal accidents have occurred in the Japanese system.6 However, ensuring the safety of HEMS is always a concern. In Japan, steep mountain ranges run through the center of the country from north to south, with the mountainous regions occupying 61% of its land area.13 In addition, because only visual flight rules (VFRs) have been used for HEMS flights in Japan, both weather and geographic conditions are major factors in the ability to fly. In fact, in the 1990s, 3 crashes of commercial helicopters in Japan occurred because of bad weather, and a total of 24 people perished. Comparing the extent of mountainous districts in Japan to other countries, Germany has almost the same land area as Japan, but the mountainous areas account for only approximately 33%. In the United Kingdom, mountainous areas occupy only approximately 15% of the total area.14 Therefore, Japan’s topography demands
72
K. Kanemaru et al. / Air Medical Journal 36 (2017) 71e76
unique consideration in terms of both weather data collection and consideration of weather minimums. In Miyazaki Prefecture, Doctor-Heli was established at the University of Miyazaki Hospital in 2012.15 Its mountainous district accounts for 88% of the total 7,736 km2 area, and 425,000 (37.4%) of its 1,137,000 residents live in these mountainous areas.16 There are few medical facilities in the mountainous areas. As a result of this, ground transport emergency medical service times to medical facilities are often prolonged. Therefore, the capabilities of HEMS in the mountains are very important, and the ability to dispatch Doctor-Heli may be associated with decreased morbidity and mortality of these patients. However, the use of HEMS in the mountains is dependent on weather conditions, and the ability to understand current weather conditions may prevent launching the aircraft to an area experiencing conditions below weather minimums. Ensuring safe helicopter operations in this region has been a particular organizational focus. As a tool to address this challenge, we established the weather webcam system (WWS). This system supplements the pilots’ standard weather report by providing direct views of 29 locations, increasing the available real-time information at the helibase. The cost to maintain this system (approximately $13,500 a year, calculated based on the rate of exchange of $1 ¼ 120 yen) is funded by the Miyazaki Prefectural government. This is the first study evaluating the use of a WWS in HEMS flight safety. This study aims to describe WWS and determine how much the WWS information can contribute to a pilot's decision making regarding current flight conditions. Materials and Methods HEMS in Miyazaki In Miyazaki, HEMS operates solely under VFRs, as with HEMS in other regions in Japan. Additionally, VFR operation is not permitted at night according to Japanese regulations. Consequently, there are no night HEMS flights. The number of HEMS requests has increased year after year and has reached 1,295 cases in the 3 years since the start of 2012. The paramedics and firefighters responding to the scene of a medical emergency anywhere in Miyazaki determine the need for and request HEMS. The pilot determines whether to accept a dispatch request by evaluating a weather map, the Aerodrome routine meteorological report, the terminal forecast, and 9 weather webcams installed by a commercial weather research company. These existing cameras were mostly positioned to evaluate road conditions. However, these locations do not necessarily accurately reflect the current weather conditions in the different mountainous areas that account for 88% of Miyazaki’s land area. As a result, dispatched flights were often aborted en route as a result of visibility and ceiling under VFRs in mountainous areas after launch. In the case of borderline weather at or en route to the scene, if the pilot makes the determination to launch and attempt the flight, the aircraft will do so with the pilot, mechanic, nurse, and physician aboard. In the case of deteriorating weather while en route to the hospital, the aircrew has several options. Often, the cloud ceiling allows them to fly a wider path around the mountains and along the coast at a lower altitude. If it is not possible to fly to the original destination hospital, the aircraft may divert to an alternative hospital that has a heliport, divert to an airport, or divert to 1 of more than 400 designated landing zones in the prefecture in order to rendezvous with a paramedic ambulance. The physician and nurse will then accompany the patient in the ambulance to the destination hospital. In the event that a request for dispatch arrives nearing sunset, the pilot evaluates the flight duration to the scene, destination hospital, and heliport in the event that the destination hospital is not the University of Miyazaki. If the pilot believes there will not be
sufficient daylight, the dispatch is canceled before launch. The physician and nurse have the opportunity to use the “doctor car” to respond to dispatches that occur during nighttime or during poor weather conditions and transport the patient aboard a fire department ambulance. WWS The weather webcams were installed in 20 spots chosen by the pilots as good indicators for the weather conditions of the different mountainous areas (Fig. 1). The images from these webcams were combined with the images obtained from the 9 weather webcams that were already installed by a commercial weather research company. In this system, the images from a total of 29 webcams were checked visually on the desktop screen to estimate the real-time meteorological conditions (Fig. 2). Specifically, to best address those conditions pertinent to weather minimums including the visibility and cloud ceiling, the weather webcams were installed at locations where the ridgeline of the mountains could be viewed widely and the weather conditions in the valleys could be confirmed. It is possible to share these meteorological conditions along the flight path with all the crewmembers as well as the pilot before launching. In addition, the communication specialists monitor the images obtained from the weather webcams when the aircraft is in flight and can inform the helicopter of the meteorological changes on the flight path via radio. Data Collection To determine the benefits of the WWS in rating weather suitability for the dispatch of a flight, an assessment based on conventional data, including the weather chart provided by the Japan Meteorological Agency and the meteorological reports (eg, the Aerodrome routine meteorological report and the terminal forecast) provided by the Miyazaki Airport (WWS), was compared with the assessment based on the information obtained from the WWS combined with the conventional data (WWSþ). Under the WWS, the pilots obtain weather conditions at the airport including type, amount, height, and location of clouds; wind direction and speed; and temperature. The pilots then use this information to estimate if the minimum cloud ceiling and visibility are likely present in the mountains. The WWS also allows the pilots to visualize many mountain ridge lines directly to evaluate cloud ceilings and visibility. The survey period was defined as approximately 6 weeks between June 26 and August 6, 2014. This period was defined as the survey period because it was during the rainy season in Japan, and the weather forecast in the mountains was especially severe during this period. The survey was performed for 26 locations within the prefecture at 8:00, 12:00, and 18:00 each day. The HEMS pilots who worked on the survey days estimated the flight dispatch probability according to the WWS and WWSþ using a scale of 1 to 4 where 1 indicates there is a 100% probability of flight, 2 the flight is probable, 3 the flight is not probable, and 4 the flight is not possible. A total of 2 pilots participated in the survey as a result of their shift schedule. Results Using WWS and WWSþ weather data sources, the weather suitability of 26 different areas was assessed at 8:00, 12:00, and 18:00 each day over a period of 42 days. Of the 3,276 weather suitability assessments, the flight probability differed between WWS and WWSþ 429 times (13.1%). Of these 429 measurements, there were 277 instances (64.6%) in which the assessment of the flight probability with the WWSþ was higher than with the WWS. In 177 of those instances, the flight probability in WWSþ was 1. In contrast, there were 152 times (35.4%) when the assessment of the flight probability in the WWSþ was lower than the WWS. In 86 of those assessments, the flight probability in WWSþ was 4 (Fig. 3).
K. Kanemaru et al. / Air Medical Journal 36 (2017) 71e76
73
Figure 1. The location of Miyazaki Prefecture and the installation site of the weather webcams.
Figure 2. The display screen of the WWS.
The area of the prefecture demonstrating the greatest difference in assessment between WWS and WWSþ was Shiiba Village with 35 (27.8%) out of 126 assessments in disagreement (Fig. 4). The top 3 areas that showed differences in the assessment had differences
nearly twice as great as the mean. These 3 areas were located in areas surrounded by steep mountains. In 49 out of 58 cases when HEMS was requested during the survey period, HEMS was dispatched. Three cases were canceled as a result of the pilot’s weather
74
K. Kanemaru et al. / Air Medical Journal 36 (2017) 71e76
Figure 3. Flight probability assessments comparing WWS and WWSþ.
assessment using the WWS. The remaining 6 were canceled as a result of insufficient daylight. Discussion This study showed that the information provided by the WWS affected the pilot assessment of the flight dispatch probability compared with the use of conventional forecasting tools. In fatal accidents involving HEMS, weather is often a factor. In a report analyzing the causes of accidents within HEMS in the United States, “A Safety Review and Risk Assessment in Air Medical Transport”17 by the Air Medical Physician Association, an introductory statement indicates that “an accident due to a single independent cause is rare.” The report also states that “pilot error was attributed as the direct or indirect cause of HEMS accidents approximately three times more often than mechanical failure; of the pilot errors, onethird were weather related.” In addition, Thies et al,18 who examined the causes of accidents in HEMS in Germany, described that 25 of 27 accidents were associated with “pilot error” and reported that “flying at low altitude under bad weather conditions is another important factor contributing to accidents.” According to an analysis of the weather and the causes of accidents, it was reported that the risk of death increased 8 times when HEMS was dispatched under bad weather conditions.19 As a step to prevent weather-related accidents, the US Federal Aviation Administration recommended the preflight risk assessment score (PRAS) in 2005. In the PRAS, the flight risk factors (pilot experience, weather, night vs. daytime operations, local vs. nonlocal flight, familiar vs. unfamiliar terrain, fatigue factors, and knowledge from a prior pilot cancellations of the same transport) were scored; the higher the points, the greater the flight risk.20 However, this assessment method has more limited usefulness for HEMS in Japan because no flights are performed at night. Furthermore, it has been reported that the usefulness of the PRAS under bad weather conditions is uncertain.21 In an effort to ensure safe flight operations during the initiation of HEMS, the Japan Transport Safety Board recommended the following 5 items in 1997: 1) recognize the importance of weather judgment in VFR operations; 2) establish a system that can provide the weather conditions along the flight path to the pilot; 3) use policy, such as returning immediately when the weather worsens; 4) fly at a minimum altitude; and 5) try to ensure that the pilot can perform instrument flight in the event of emergency resulting from deteriorating weather conditions.
We established the original WWS for the purpose of ensuring safety under variable weather conditions in the HEMS system in Miyazaki. There were differences in the assessment of flight conditions in 429 instances (13.1%) between the WWSþ and WWS. From these results, it can be concluded that the WWS is a system with information that consistently influences the assessment of the flight conditions and suitability for flight in at least 3 of 26 areas. In addition, a more favorable assessment of flight conditions was shown 277 times and a less favorable one was shown 152 times in the WWSþ in comparison with the WWS. This indicated that WWS provided additional operational weather assessment data compared with traditional weather information alone. These results indicated that the meteorological forecast based on WWS was relatively limited and tended to decrease the flight probability of the pilots’ assessment when compared with WWSþ. In other words, it was suggested that the probability of a safe flight could not be assessed consistently based on WWS. The flight probability was assessed as less than 1 in the WWS and was assessed as 1 in WWSþ 177 times. This indicated that the predicted probability of a flight by HEMS might increase when using the WSS. This may lead to a larger number of accepted dispatches, providing HEMS capability for more patients in the mountains who rely on it. Conversely, flight probability was assessed as 1, 2, or 3 based on WWS but assessed as 4 86 times based on WWSþ, indicating that the WWS may prevent dispatching the aircraft under unsuitable weather conditions. Based on the findings in this survey and after reviewing the recommendations by the Japan Transport Safety Board, the recommendations can be restated as follows: 1) the WWS is a system that allows all HEMS crewmembers to assess and share important weather conditions on a screen, 2) the WWS is a system that can provide weather information along the flight path to the pilot before dispatch, and 3) the WWS is a system that enables immediate stand-down conditions via radio when worsening weather is detected on the images by the weather webcams. Therefore, WWS alone meets 3 of the 5 recommendations. There have been no fatal accidents since HEMS began in Japan in 2001 using the following flight methods as safety measures: taking off and landing at predetermined landing zones, the use of twin engines (helicopter models AW109SP, Bell429, BK117, EC135, and MD902), flights limited to daytime, and flights requiring 1 pilot and 1 mechanic on board.6 The WWS, which was established to increase the pilots' views, was an example of 1 way of enhancing safety by augmenting weather information.
K. Kanemaru et al. / Air Medical Journal 36 (2017) 71e76
75
Figure 4. Three areas with the greatest difference between WWS and WWSþ.
One potential limitation of this study is the possibility that the results were exaggerated as a result of the rainy season. Performing the survey of WWS for a 1-year period may be necessary to establish this. In addition, the pilot’s judgment of the flight probability using WWS was based on no standard rules beyond the perceived visibility and cloud ceiling on the screen. An assessment of the WWS based on more standardized criteria or linked to a form of automated weather observing station may be required in the future.22 Because HEMS in Japan operates during daylight only, these results may not necessarily apply to night operations. Finally, in this study, the flight probability was estimated 3 times a day regardless of whether a dispatch was requested. The ideal assessment of the usefulness of the WWS would be the assessment of flight probability by the WWS and WWSþ upon receipt of a dispatch request and the comparison of its probability with the actual flight probability. Conclusion Japan has significant areas of mountainous terrain that are characteristically susceptible to bad weather. In the past, crashes of commercial helicopters occurred because of bad weather. The nation also restricts nighttime VFR operations in an effort to prevent crashes from low visibility conditions. Considering these facts, we established the WWS for the purpose of safe HEMS operations within the Miyazaki Prefecture. This system allows aircrew to visually evaluate the weather along the flight path before a flight, which greatly helps pilots to judge the flight probability. The WWS provides crucial weather condition information about the
mountainous portions of the Miyazaki Prefecture, contributing to safe HEMS operations and helping to maintain the record of no fatal collisions in the HEMS system. References 1. Hinkelbein J, Schwalbe M, Neuhaus C, et al. Incidents, accidents and fatalities in 40 years of German helicopter emergency medical system operations. Eur J Anaesthesiol. 2011;28:766e773. 2. McGinnis K, Judge T, Nemitz B, et al. Air Medical Services: future development as an integrated component of the Emergency Medical Services (EMS) System: a guidance document by the Air Medical Task Force of the National Association of State EMS Officials, National Association of EMS Physicians, Association of Air Medical Services. Prehosp Emerg Care. 2007;11:353e368. 3. Butler B. Helicopter emergency medical services and weather-related accidents. Air Med J. 2014;33:84e85. 4. Mashiko K, Matsumoto H, Hara Y, Yagi T. Realising the potential : challenges and opportunities for HEMS in Japan. AirRescue. 2013;3:124e126. 5. Nishikawa W, Yamano Y. An overview of the development of helicopter emergency medical services in Japan. Air Med J. 2010;29:288e291. 6. Nishikawa W, Yamano Y. HEMS flight safety. http://airmed.eu/pdfs/P_04_ Nishikawa.pdf. Accessed July 5, 2016. 7. Matsumoto H, Kanemaru K, Hara Y, et al. Development of an educational program for the helicopter emergency medical services in Japan. Air Med J. 2013;32:84e87. 8. Abe T, Takahashi O, Saitoh D, Tokuda Y. Association between helicopter with physician versus ground emergency medical services and survival of adults with major trauma in Japan. Crit Care. 2014;18:R146. 9. Yamaguchi T, Mashiko K, Sakamoto Y, et al. Comparison between helicopter emergency medical service and ambulance transportation to rescue people injured by traffic crashes in Japan. Prehosp Disaster Med. 2007;22:31e33. 10. Hata N, Kobayashi N, Imaizumi T, et al. Use of an air ambulance system improves time to treatment of patients with acute myocardial infarction. Intern Med. 2006;45:45e50. 11. Matsumoto H, Mashiko K, Hara Y. Effectiveness of a “doctor- helicopter” system in Japan. Isr Med Assoc J. 2006;8:8e11.
76
K. Kanemaru et al. / Air Medical Journal 36 (2017) 71e76
12. Hata N, Shinada T, Kobayashi N, et al. Severity of cardiovascular disease patients transported by air ambulance. Air Med J. 2011;30:328e332. 13. 1e8 area by configuration, gradient, and prefecture. Japanese Statistical Year Book 2016 [in Japanese]. http://www.stat.go.jp/data/nenkan/01.htm. Accessed July 29, 2016. 14. The vulnerability of a nation. Ministry of Land, Infrastructure, Transport and Tourism [in Japanese]. http://www.mlit.go.jp/common/000997376.pdf. Accessed July 29, 2016. 15. Katzer RJ. Japanese Prefecture integrates physician staffed medical helicopter into regional EMS system. http://www.emergency-live.com/en/news/japaneseprefecture-integrates-physician-staffed-medical-helicopter-into-regional-ems-system/. Accessed June 26, 2016. 16. Miyazaki Mountainous Areas Promotion Plan. July 2015 [in Japanese]. http:// www.pref.miyazaki.lg.jp/chusankan-chiiki/kense/kekaku/20150711094913.html. Accessed July 29, 2016.
17. Blumen IJ, Coto J, Maddow CL, et al. A safety review and risk assessment in air medical transport. Air Medical Physician Handbook. Salt Lake City, UT: The Air Medical Physician Association; 2002:53e55. 18. Thies KC, Sep D, Derksen R. How safe are HEMS-programmes in Germany? A retrospective analysis. Resuscitation. 2006;68:359e363. 19. Baker SP, Grabowski JG, Dodd RS, Shanahan DF, Lamb MW, Li GH. EMS helicopter crashes: what influences fatal outcome? Ann Emerg Med. 2006;47: 351e356. 20. Winn W, Thomas F, Johnson K. Strategies to reduce US HEMS accidents. Air Med J. 2012;31:78e83. 21. Thomas F, Groke S, Handrahan D. Intermountain life flight preflight risk assessment score and transport outcomes. Air Med J. 2011;30:49e50. 22. Automated Surface Observing Syste (ASOS). https://www.ncdc.noaa.gov/dataaccess/land-based-station-data/land-based-datasets/automated-surface-observingsystem-asos. Accessed December 20, 2016.