Air Force Safety Center Research Articles

A longitudinal pre-post study: An evaluation of the Department of the Air Force bundled occupational fall prevention efforts.

Fall injuries are the second leading cause of traumatic injury and death for all US workers and are a leading injury concern for the Department of the Air Force (DAF). Bundled interventions can improve the likelihood of injury reduction, especially in large, heterogeneous working populations. In 2013, the DAF implemented the "Air Force Fall Prevention Focus," a bundled intervention of prevention efforts designed to reduce occupational fall injury events among DAF members. The purpose of this study is to describe the burden and risk factors associated with fall injuries and evaluate the effectiveness of the Fall Prevention Focus in reducing the burden of fall injuries. The National Institute for Occupational Safety and Health (NIOSH) partnered with the US Air Force Safety Center (AFSEC) to examine the impact of the Fall Prevention Focus as a bundled intervention. Injury events included a narrative description of the injury event, demographics, work environment, job tasks, and other structured details. Descriptive statistics and pre-post longitudinal modeling were used to evaluate changes in fall injury rates. The Fall Prevention Focus Implementation (2013-2018) resulted in an annual 10.4% (95% confidence interval [CI]: 8.5%, 12.2%) reduction, and a 6-year cumulative 48.3% (95% CI: 41.4%, 54.3%) reduction in fall injury event rates by 2018. Safety in the DAF involves a comprehensive approach. Documenting the impact of the Fall Prevention Focus may help translate these findings to improve fall prevention efforts in other sectors of the military and high fall-risk industries in the private sector, such as construction.

Trending and analysis of payload vs. All low earth conjunction data messages below 1000 km, from 2016 through 2021

The Air Force Safety Center is developing a program to quantify the distribution of risks to the orbital environment across time and space by trending and analyzing orbital conjunction events. Previous efforts described automating the intake of Conjunction Data Messages (CDM) previously generated by the 18th and 19th Space Defense Squadrons (18 SDS, 19 SDS) and developing pre-processing scripts necessary to populate information germane to orbital collision risk assessment. The intent of the current effort is to account not only for the probability of collision (Pc), but also the consequence of the debris products from a collision to the low Earth orbital environment, should it occur. To accomplish this, the team analyzed all reported CDMs of conjunction events below 1000 km in altitude, between 1 Jan 2016 and 31 Dec 2021. 18 SDS reported Pcs were re-computed using the Foster-92 method. A circular 2-dimensional interaction area was applied instead of a square, to reduce conservatism and lend closer towards realism. Hard Body Radii estimates were pooled from externally sourced information, including The Aerospace Corporation and various open sources. When not available, radius estimates were imputed based on available data. Covariance information was sourced from CDMs. For consequence, the amount of damaging, lethal non-trackable and trackable debris products were estimated using The Aerospace Corporation's IMPACT 8.0 model. The model accounts for relative velocity, object masses, mass distribution, and structure. Object distribution and structure were inferred from the object type field in the CDMs. Relative velocity was also sourced from CDMs. The object masses were sourced from data furnished by The Aerospace Corporation and Union of Concerned Scientists satellite database. The expected number of damaging, lethal non-trackable, and trackable debris products were multiplied by the Pc to produce a quantitative risk metric for each conjunction event. Risks were adjusted to account for likely collision avoidance maneuvers based on satellite age, mass, and Pc. The results show a logarithmic increase in total risk over time, particularly after 2020. This change correlates to the launch of Starlink and OneWeb satellites into orbit, and analysis confirmed that the uptick in risk is attributable to the launch of those large constellations into orbit. The risk metric for Starlink vs. Starlink conjunctions was further adjusted to more accurately account for proprietary processes and high accuracy ephemerides which enables better information for performing collision avoidance maneuvers. This adjustment reduced the slope of the risk trends starting in 2020, but they are still positive and logarithmic. Spatial domain analysis revealed that the preponderance of debris production risk for reported conjunctions below 1,000 km resides between the altitudes of 450 km and 850 km. The spatial distribution of risk by altitude changed starting in 2020 due to the launch of large constellations, resulting in a higher and more evenly distributed risk of debris production between 350 and 1,000 km. Results also indicate that more trackable debris would have likely been generated by collisions between payloads and trackable objects, with perigees below 1,000 km than the 37 that have been confirmed and cataloged during that time period. However, analysis of the four confirmed payload collision events with cataloged debris produced a bootstrapped confidence interval of trackable debris generated per year suggesting the trackable debris production rate estimated here is within a plausible range. Planned future work looks to address known assumptions and limitations. This work is the first known effort to quantitatively analyze historical risks of conjunction events using full sets of CDM data and fuse them with the latest semi-analytical breakup algorithms. Analyses such as these are necessary to better inform ongoing and future Space Safety and Space Traffic Management policy development efforts within the US Government and internationally.

Trending analysis of historical conjunction data messages

The United States Air Force maintains the Catalog of Earth orbiting satellites, or SATCAT. In February of 2009, a collision between Cosmos 2251 and Iridium 33 occurred. This event not only generated thousands of pieces of debris, but also heightened international interest in preventing future orbital collisions. Future potential collisions, or conjunctions, are predicted and warned of by the 18th Space Control Squadron (18 SPCS), across the space community, using Conjunction Data Messages (CDMs). The research team requested, processed, analyzed, and trended the historical catalog of 23 million CDMs across spatial and temporal domains for aggregate risk assessment in each of the major Earth orbit classes.This effort is in the spirit of the Air Force Safety Center's (AFSEC's) vision, which is to achieve a proactive safety culture of hazard identification and risk management across the Air Force, to prevent mishaps. The type and depth of analysis presented here will increase in the future to better inform the hazards of the orbital environment and cultivate space mishap prevention.

Spatial disorientation mishap trends in the U.S. Air force 1993-2013.

Spatial disorientation is a significant factor in a large percentage of military Class A aviation mishaps. While previous studies have analyzed accident statistics, they often suffer from methodological flaws, which lead to questionable conclusions. The current study relied upon the Air Force Safety Automated System to document U.S. Air Force Class A mishap investigations during the past 21 yr. Human Factors Analysis and Classification System codes were used to determine mishaps involving pilot spatial disorientation. The data were combined with data from the Reliability and Maintainability Information System to determine the accident rate per flight hour. There were 72 spatial disorientation (SD) mishaps analyzed, resulting in loss of 101 lives and 65 aircraft since fiscal year (FY) 1993 for a total monetary cost of 2.32 billion. Class A mishaps involving spatial disorientation had a higher rate as a function of hours flown for helicopter and fighter/attack fixed wing aircraft than other aircraft. Additionally, mishap rates for F-16 fighter/attack aircraft were marginally larger than for other fighter/attack aircraft. Although SD mishaps at night had similar mishap rates to daytime SD mishaps when adjusted by flight hours, SD mishaps account for a larger percent of Class A mishaps during the night than during the day. SD mishaps were analyzed in terms of Class A mishaps per million flight hours. Results indicate that future SD research should be focused on fighter/attack and helicopter platforms. Updates to the Air Force safety center database are recommended.

Mechanisms of Basketball Injuries Reported to the HQ Air Force Safety Center: A 10-Year Descriptive Study, 1993–2002

Background Basketball is the most popular sport among the U.S. Air Force (USAF) active duty population and causes a large number of lost-workday injuries. The purpose of this study is to describe how basketball injuries occur to allow development of effective countermeasures. Methods This study used data derived from safety reports obtained from the USAF Ground Safety Automated System. Basketball injuries for the years 1993–2002 that resulted in at least one lost workday were included in the study conducted in 2003. Narrative data from 32,818 safety reports were systematically reviewed and coded in order to categorize and summarize mechanisms associated with these injuries. Results A total of 2204 mishap reports involving active duty USAF members playing basketball were documented by the study. This study identified seven mechanisms causing basketball injury. Two similar causes involving jumping (landing awkwardly and landing on someone's foot) accounted for 43% of basketball injuries followed by collisions with other players (10%). Conclusions This study shows that mechanisms of basketball-related injury can be identified using the detailed information found in USAF safety reports. Knowledge of leading hazards or mechanisms for basketball injuries can be used to prioritize and develop prevention strategies. Basketball is the most popular sport among the U.S. Air Force (USAF) active duty population and causes a large number of lost-workday injuries. The purpose of this study is to describe how basketball injuries occur to allow development of effective countermeasures. This study used data derived from safety reports obtained from the USAF Ground Safety Automated System. Basketball injuries for the years 1993–2002 that resulted in at least one lost workday were included in the study conducted in 2003. Narrative data from 32,818 safety reports were systematically reviewed and coded in order to categorize and summarize mechanisms associated with these injuries. A total of 2204 mishap reports involving active duty USAF members playing basketball were documented by the study. This study identified seven mechanisms causing basketball injury. Two similar causes involving jumping (landing awkwardly and landing on someone's foot) accounted for 43% of basketball injuries followed by collisions with other players (10%). This study shows that mechanisms of basketball-related injury can be identified using the detailed information found in USAF safety reports. Knowledge of leading hazards or mechanisms for basketball injuries can be used to prioritize and develop prevention strategies.

Mechanisms of Flag-Football Injuries Reported to the HQ Air Force Safety Center: A 10-Year Descriptive Study, 1993–2002

Flag (touch or intramural) football is a popular sport among the U.S. Air Force (USAF) active duty population and causes a substantial number of lost-workday injuries. The purpose of this study is to describe the mechanisms of flag-football injuries to better identify effective countermeasures. The data were derived from safety reports obtained from the USAF Ground Safety Automated System. Flag-football injuries for the years 1993-2002 that resulted in at least one lost workday were included in the study conducted in 2003. Narrative data were systematically reviewed for 32,812 USAF mishap reports; these were then coded in order to categorize and summarize mechanisms associated with flag football and other sports and occupational injuries. Nine hundred and forty-four mishap reports involving active duty USAF members playing flag football met the criteria for inclusion into this study. Eight mechanisms of injury were identified. The eight mechanisms accounted for 90% of all flag-football injuries. One scenario (contact with another player) accounted for 42% of all flag-football injuries. The most common mechanisms of injury caused by playing flag football can be identified using the detailed information found in safety reports. These scenarios are essential to developing evidence-based countermeasures. Results for flag football suggest that interventions that prevent player contact injuries deserve further research and evaluation. The broader implications of this study are that military safety data can be used to identify potentially modifiable mechanisms of injury for specific activities such as flag football.

Mechanisms of Slow-Pitch Softball Injuries Reported to the HQ Air Force Safety Center: A 10-Year Descriptive Study, 1993–2002

Softball is a popular sport in civilian and military populations and results in a large number of lost-workday injuries. The purpose of this study is to describe the mechanisms associated with softball injuries occurring among active duty U.S. Air Force (USAF) personnel to better identify potentially effective countermeasures.Data derived from safety reports were obtained from the USAF Ground Safety Automated System in 2003. Softball injuries for the years 1993-2002 that resulted in at least one lost workday were included in the study. Narrative data were systematically reviewed and coded in order to categorize and summarize mechanisms associated with these injuries.This report documents a total of 1181 softball-related mishap reports, involving 1171 active duty USAF members who sustained one lost-workday injury while playing softball. Eight independent mechanisms were identified. Three specific scenarios (sliding, being hit by a ball, and colliding with a player) accounted for 60% of reported softball injuries.Mechanisms of injury for activities such as playing softball, necessary for prevention planning, can be identified using the detailed information found in safety reports. This information should also be used to develop better sports injury coding systems. Within the USAF and U.S. softball community, interventions to reduce injuries related to the most common mechanisms (sliding, being hit by a ball, and colliding with a player) should be developed, implemented, and evaluated.

Recurrent Error Pathways in HFACS Data: Analysis of 95 Mishaps with Remotely Piloted Aircraft

According to Reason's model of accident causation, mishaps tend to fall into recurrent patterns. This model is the foundation for the Human Factors Analysis and Classification System (HFACS), which is now widely used in aviation accident analysis. The purpose of this study was to determine if it was possible to use HFACS to identify recurrent error pathways within an existing mishap database. All MQ-1 Predator remotely piloted aircraft (RPA) mishaps and safety incidents reported to the Air Force Safety Center during fiscal years 1997-2005 were evaluated and entered into a mishap database (N = 95). An exploratory principal component analysis (PCA) was used to assess the factorial structure within the set of crewmember-related mishaps (N = 48). The results of the PCA were used to define recurrent pathways from latent to active failure and hence mishaps. A tree diagram was subsequently created to quantitatively assess the associations identified in the PCA. Four factors were identified, each consisting of one of the HFACS categories of active failure and one or more categories of latent failure. Two additional factors were identified, consisting of fatigue and motivational latent failures. Based on analysis of the tree diagram, the majority of mishaps were caused by latent failures involving organizational factors and the technological environment. It was possible to identify four recurrent error pathways associated with the four types of HFACS active failures within this sample of RPA mishaps. Two of these error pathways, accounting for 57% of crewmember-related mishaps, were consistent with situation awareness errors associated with perception of the environment.

Cost Analysis of Military Eye Injuries in Fiscal Years 1988–1998

Army, Navy, and Air Force safety center ground eye injuries were evaluated from fiscal year 1988 through fiscal year 1998. The U.S. Army Safety Center data revealed that the average Army military eye injury mishap caused a loss of 6.1 days from work, at a cost averaging 9724 dollars. The U.S. Navy Safety Center data showed that the average Navy military eye injury mishap caused a loss of 5.9 days from work, at a cost averaging 4222 dollars. The Air Force Safety Center data revealed that the average Air Force eye injury mishap caused a loss of 4.7 days from work, at a cost averaging 3196 dollars. Comparing safety center data with Defense Medical Surveillance System data exposed an underreporting of safety center data by at least 250%. To improve accurate meaningful data collection, an automated eye injury collection system should be initiated.

Descriptive Analysis of Military Eye Injuries from Fiscal Year 1988 to 1998

An 11-year retrospective study of ground eye injuries collected by the Army Safety Center, Navy Safety Center, and Air Force Safety Center from fiscal year 1988 through 1998 was performed. The statistics for eye injuries indicate that the average Army, Navy, and Air Force individual sustaining an eye injury is a 20- to 24-year-old man with a rank of E2 through E5. The average military individual sustaining an eye injury is not wearing eye protection when injured. In addition, Army personnel lost 1.9 more workdays, Navy personnel lost 1.5 more workdays, and Air Force personnel lost 3.4 more workdays than those individuals who were wearing eye protection at the time of the eye injury. Proactive vision conservation education at local levels needs to focus on the military personnel that are at the highest risk for an eye injury.