Business aircraft accidents were down overall worldwide in 2012, but those involving U.S. business jets have been increasing, according to the latest statistics from business aviation safety expert Robert E. Breiling Associates.

At the same time, U.S. helicopter accidents jumped notably in 2012, while the non-U.S. registered helicopter fleet improved its safety record.

The number of U.S. business jet accidents increased by five in 2012 to 19 accidents. Of those, five were fatal and involved 21 deaths. This compares to 14 business jet accidents – and no fatal accidents – in 2011.

Three of last year’s fatal business jet accidents involved U.S.-registered aircraft that crashed outside the U.S. They included a G-IV crash in the Congo that killed four, another G-IV crash in France with three fatalities (all crew) and a Learjet 35 crash in Mexico that resulted in five fatalities.

The other two fatal crashes occurred in North Carolina – a Cessna CE-501 involving five fatalities and a Cessna CE-550 that was fatal to two.

While the number of U.S. business jet accidents have been on the rise, the number of incidents declined from 54 to 39. According to Breiling, though, the number of landing-related accidents and incidents involving business jets spiked in 2012 to 58%. This is up from an average of between 40-45% over the past five years, Breiling says. He notes the landing accidents were just as prevalent with jets flown by two crew as they were by single-pilot operations.

While the U.S. business jet fleet’s accident rate worsened in 2012, the U.S. business turboprop fleet actually improved its accident record. Business turboprops were involved in 29 accidents in 2012, compared with 43 a year earlier.

The most significant improvement came with owner-flown/personal use operations, where the number of turboprop accidents were cut in half, from 22 in 2011 to 11 last year.

The overall number of turboprop fatal accidents dropped from 13 in 2011 to seven last year, and correspondingly, the number of fatalities fell from 32 to 15.

Non-U.S. registered business jets were involved in one fewer accident in 2012 (10) and turboprops were involved in 40 accidents, down from 44 in 2011.

Likewise, incidents involving non-U.S. registered business aircraft were down: incidents involving jets dropped from 11 in 2011 to six last year and turboprops from 13 to 10.

Fatal accidents also declined from four in 2011 to two involving the business jet fleet. But non-U.S.-registered business turboprop were involved in more fatal accidents last year (18) than in 2011 (16). The majority of the fatal accidents came in the commuter/air taxi segment.

As for helicopters, U.S. twin-turbine helicopter accidents jumped from six in 2011 to 16 last year, including three fatal accidents with seven fatalities. Single-turbine helicopters were involved in 57 accidents last year – up from 50 a year earlier.

But outside the U.S., twin-turbine helicopter accidents dropped from 33 in 2011 to 19 last year. Likewise, single-turbine helicopters were involved in 94 accidents last year, down from 108 a year earlier, according to preliminary Breiling data.

Breiling complies business aircraft and helicopter accident data worldwide and publishes the information in its Annual Business Turbine Accident Review.