The Air Force saw an increase in major accidents involving on-duty airmen in fiscal 2015, after the safest year on record in 2014 change from 2014 which was the safest year on record.

According to a news release from the service, there were 19 Class A accidents in fiscal 2015, compared with seven in 2014. But on-duty fatalities decreased, dropping from 11 in 2014 to 10 in 2015.

Class A mishaps are generally defined as major accidents that involve loss of life or crippling damage to peopleequipment and property.

According to the annual occupational safety report published by the safety center, aircraft maintenance "is still the leading functional area for mishap count" of all severities, Class A and otherwise.

The report noted that there "are many hazards on the flight line" including "outdoor exposure to weather, equipment, a large immovable object with many sharp objects hanging down, and duties driven by a tight timeline."

Across all classes and severities of mishaps, aircraft maintenance was the leading cause in terms of number of accidents between 2011 and 2015. Accidents during training also occurred with greater frequency than other activities, as did accidents that involved security forces.

Although the number of accidents that involved fire fighting was not as high numerically, the report noted that those mishaps are more damaging to health and property, and costlier.

Altogether, Class A mishaps caused nearly $35 million worth of damage in 2015, the safety report said. Mishaps of less serious classes caused about $53 million worth of damage.

The Air Force Safety Center said the 19 mishaps in 2015 are in line with the 10-year average of 18.5 accidents a year. 2015's accidents come out to a rate of about 1.12 per 100,000 flight hours.

The 10 fatalities are broken down into six deaths from aviation mishaps and four on-duty ground fatalities. In 2014, there were 10 aviation mishap deaths and one on-duty ground fatality.

2015 also saw an increase in off-duty fatalities, rising to 47 from 42 in 2014.

"A change in mishaps from one year to the next doesn't mean we got it right one year and relaxed the next," said Maj. Gen. Andrew Mueller, who became the Air Force chief of safety and commander of the safety center in July. "It's important to look at trending data and see the larger picture rather than focus only on changes from one year to the next."

2015 also saw an increase in off-duty fatalities, rising to 47 from 42 in 2014.

Altogether, Class A mishaps caused nearly $35 million worth of damage in 2015, the safety report said.

According to the annual occupational safety report published by the safety center, aircraft maintenance "is still the leading functional area for mishap count." of all severities.

The report noted that there "are many hazards on the flight line" including "outdoor exposure to weather, equipment, a large immoveable object with many sharp objects hanging down, and duties driven by a tight timeline."

"Lessons learned 68 years ago are just as applicable today," Mueller said. "We learn from the experiences of each other and that enables us to decrease our chances of repeating mistakes that impede safe operations and increase our consistency in repeating sound practices."

On the opposite end of the spectrum from Class A mishaps, the safety report also uncovered there have been 1,167 accidents involving airmen and Air Force civilians playing basketball since fiscal 2011.