Glossary

The terms used across the record, defined once.

AccidentAn occurrence classified as an accident: a death or serious injury, or substantial damage to the aircraft. Incidents are recorded separately and are not in the accident rate.

Aircraft-yearOne aircraft on the US register for one year. The exposure unit for every rate we publish. It counts years on the register, not hours flown.

ALEX™ BriefA StratoData report on one aircraft from its registration number: registration history, the records tied to the airframe, how it flies and its modeled expected loss.

Business useOwner-flown and corporate flying under Part 91, fractional programs under Part 91 subpart K, and on-demand charter under Part 135.

Aircraft classOne of six groups of turbine airplanes used to pool the record: light, midsize and large-cabin jets; single-engine, light twin and heavy twin turboprops.

Credibility (Z)The weight an account’s own loss history carries in its price. The class rate carries the rest, 1 minus Z.

Deregistered aircraftAn aircraft whose US registration has been cancelled: destroyed, exported, retired or not renewed. Counted in exposure for the years it was registered.

DestroyedDamage category: the aircraft is damaged beyond economical repair.

Fatal accidentAn accident with at least one death within 30 days.

Publication floorThe minimum exposure, in aircraft-years, below which no rate is published.

Loss ratioIncurred losses divided by earned premium. Direct figures are before reinsurance and net figures after; the two are never combined.

RestatementA published change to a figure, logged with the old value, the new value, the date and the reason.

Substantial damageDamage category: damage that adversely affects the structural strength, performance or flight characteristics of the aircraft and would normally require major repair.