History of Flight
On June 9, 2018, about 2000 Alaska daylight time, a float-equipped Piper PA-18 airplane, registered N1203A, was substantially damaged when it collided with terrain near Sitka, Alaska. The commercial pilot and passenger sustained fatal injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 sightseeing flight.
The pilot was co-owner of Frontier Charters and Lodge in Sitka. According to the pilot's mother, the flight was a non-revenue wildlife sightseeing tour to view mountain goats. The pilot filed and activated a local flight plan with Juneau Flight Service, planning to depart Sitka Seaplane Base (A29) at 1934 and return at 2030, with intended route to Katlian Bay and Nakwasina Sound. When the airplane was deemed overdue, an alert notice was issued by Juneau Flight Service at 2239, and the US Coast Guard (USCG) Sector Juneau coordinated a search with Alaska State Troopers and Civil Air Patrol. No emergency locator transmitter (ELT) signal was received. The airplane was not equipped with ADS-B, and no radar track was available.
On June 10 about 2210, a USCG MH-60T helicopter located the wreckage about 0.2 mile upriver from Katlian Bay on an arm of the Katlian River. The pilot was in the front seat; the passenger was missing. The fatally injured passenger was located the next day at 1009, downriver from the airplane, according to USCG records.
Wreckage and Impact Information
The airplane came to rest about 70° nose-down and wings-level in a small brackish river subject to tidal effects. National Transportation Safety Board investigators and an FAA safety inspector accessed the site on June 12 at low tide after multiple tidal cycles. The wreckage faced upriver (about 110°), with the forward 3 feet of aluminum floats severely buckled and deformed upward about 70°. The aft fuselage was displaced and twisted right. An initial impact site was identified about 20 ft upstream, with a 6-by-6 ft depression and small debris, including engine cowlings. Two large tree trunks at the impact site had fresh propeller cuts, but surrounding trees showed no impact marks. All major components were present.
Flight control continuity was established. The aileron control cable was separated at the left wing root with broomstraw signatures indicating overload failure at impact. The left wing root leading edge had an indentation matching a deadfall tree trunk at the initial impact site. Left and right wings were separated at rear connections and rotated forward. The left flap control rod was fractured with dull overload signatures; the right flap was attached and up. The empennage was displaced and twisted right.
Aircraft and Pilot Information
The airplane, a Piper PA-18, was purchased in 2017 and fitted with Edo 2000 floats in May 2018. The front and rear seats had TSO C114-compliant four-point AmSafe restraint systems with inertia reels. No rear seat control stick was installed.
The pilot's logbook was not found. At his last FAA medical exam (March 20, 2018), he reported 1,600 total hours and 180 hours in the previous 6 months. An instructor stated the pilot had about 1,000 hours in a Cessna 185 floatplane, 20-40 hours in a PA-18 floatplane, and about 100 hours in his wheel-equipped PA-18. On June 18, 2015, his commercial certificate was suspended for 90 days for operating an unairworthy aircraft and failing to log maintenance.
A friend described the pilot as flying "right up to the limit of its capabilities" but safe. The pilot's mother stated the PA-18 was his personal airplane, not used for lodge clients.
Survival Aspects
USCG personnel on scene reported the pilot was strapped into the front seat with only the lap belt; shoulder harness fittings were not inserted into the buckle. The overhead inertia reel was intact and attached to a structural tube fractured at both ends and deformed at the center bracket. The reel was functional. The lapbelt buckle connector was undamaged and functional. The rear seat shoulder harnesses and inertia reel were firmly attached to overhead tubing separated by fractures at welded joints; the reel was functional, and harnesses showed no forced release. The lapbelt webbing was attached to floor structure, with the buckle significantly deformed outward.
Additional Information
An aerodynamic stall is an aerodynamic condition where smooth airflow over wings is disrupted, resulting in loss of lift, occurring when the angle of attack exceeds the critical angle of attack at any airspeed, attitude, or power setting (from the Airplane Flying Handbook).
Medical and Pathological Information
Autopsies by the Alaska State Medical Examiner's Office determined the cause of death for both pilot and passenger as blunt force injuries. Toxicology tests on the pilot were negative for ethanol, drugs, and carbon monoxide.
Tests and Research
The ELT, an Ack Technologies model E-01 transmitting on 121.5 MHz, was tested and transmitted successfully but only tested satisfactorily 3 out of 6 times with mechanical activation.
No preaccident anomalies were noted with the airframe or engine that would have precluded normal operation.