Piper PA18 N1203A

Summary

On 9 June 2018 at about 04:00 local time, a Piper PA18 registered N1203A was involved in an accident near Sitka, Alaska, United States. 2 people were on board and 2 died. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

9 June 2018 at 04:00

Classification

Accident

Location

Sitka, Alaska, United States

Coordinates

57.1717, -135.2767

Aircraft

Piper PA18

Registration

N1203A

Category

Airplane

Year built

1951

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Sitka → Sitka

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

ANC18FA044

2 people died.

The pilot's exceedance of the airplane's critical angle of attack for unknown reason, which resulted in an aerodynamic stall and a loss of control.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

The pilot was flying a lodge client on a wildlife viewing flight in a floatplane. About 2 hours after the planned return time, the airplane was reported overdue and a search was coordinated. The airplane wreckage was located nose down in a confined shallow river the next day. The airplane did not have GPS, ADS-B or a recording system, and there was no radar coverage in the area of the accident; therefore, the flight track was unknown. The airplane impacted the river bottom in a 70 ° nose down attitude with the front floats absorbing much of the energy and the aft fuselage displaced and twisted right, indicative of impact during a stall/spin. All flight controls were intact and continuous, and the engine exhibited no anomalies. The propeller blades exhibited rearward bends with torsional twist and some chordwise scrapes, and propeller strikes were evident on deadfall trees trunks at the initial impact site, which are all indications of impact with engine power. The right fuel tank cap was not located but given that there was evidence of engine power at impact, it is unlikely that fuel siphoning/exhaustion was causal. It is likely that the pilot was maneuvering the airplane in slow flight to show the passenger wildlife, and, in doing so, exceeded the airplane's critical angle of attack, resulting in the stall. The airplane was equipped with 4-point shoulder harnesses on both seats; however, first responders reported that the pilot did not have the shoulder harness fittings inserted into the lapbelt buckle. The rear seat passenger was ejected during the impact and examination of the shoulder harnesses for his seat revealed no indication of deformation of the webbing or metal end fittings, indicating he was also likely not using the shoulder harnesses at the time of impact. His lapbelt buckle however, was deformed although it was fully functional.  It is possible that the use of the shoulder harnesses may have prevented the rear seat passenger's ejection and/or mitigated some of the occupants' injuries had they been in use at the time of the accident.

Quoted verbatim from the NTSB record.