The Lemon Index
Photos: ZLEA (Wikimedia Commons)
31accidents
35%were fatal
27deaths
26%aircraft destroyed
What happened. NTSB's defining event, share of accidents.
Low altitude operation/event19%
Unknown or undetermined10%
Loss of control in flight10%
VFR encounter with IMC6%
Miscellaneous/other6%
Abrupt maneuver6%
Pilot or plane? How often NTSB listed an aircraft problem among the causes.
18%the plane was part of the cause
engine, systems, structure or propeller
engine, systems, structure or propeller
82%people or weather only
pilot decisions, control, fuel planning
pilot decisions, control, fuel planning
Out of 11 accidents where NTSB recorded a cause. When the plane was a cause, it was most often the main rotor system.
When. Phase of flight.
Maneuvering32%
Enroute29%
Landing16%
Takeoff6%
Other6%
Accidents per year.
20080
20090
20100
20111
20120
20131
20142
20150
20163
20171
20181
20193
20202
202110
20221
20230
20240
20256
More planes flying means more accidents, so counts aren't a safety score by themselves. Compare the shares above.
Source: NTSB aviation accident database, U.S. accidents 2008–2025. ntsb.gov · Every plane
Updated