History of Flight
On November 7, 2017, about 1204 eastern standard time, an Icon Aircraft A5 special light sport amphibious airplane, registration N922BA, sustained substantial damage when it crashed near Clearwater, Florida. The private pilot sustained fatal injuries. The airplane was operated as a Title 14 CFR Part 91 personal flight.
The flight departed from Island Ford Lake in Odessa, Florida, about 1147. According to data from the Icon digital to analog (DAC) data memory unit, the airplane climbed to a GPS altitude of 1,909 ft and proceeded north for 4 nautical miles before turning west toward the Gulf of Mexico. It then flew for 10 nm at a GPS altitude of about 600 ft and descended over the gulf before turning south. During the final 3 minutes, the airplane traveled south along the shoreline. In the last 2.5 minutes, the pilot conducted three maneuvers with high angles of attack (AOA) and load factors of almost 2 Gs. During the final maneuver, the airplane entered a right turn, engine power decreased, and AOA reached 16°. The last recorded data point at 1203:41 showed airspeed 75 knots and heading 354°.
The Rotax engine control unit last recorded data at 1203:43 with engine speed 2,829 rpm and throttle position 27%.
Multiple witnesses reported seeing the airplane flying very low, between 5 and 300 ft, over the water as it maneuvered south close to the shoreline. Some observed steep turns and high-pitch climbs up to about 500 ft, with the engine sounding normal. A commercial fisherman located about 900 ft north of the accident site stated that the airplane flew from the north close to houses, then passed his position, descended briefly, and climbed. After a steep climb, the airplane descended on an easterly heading in a steep nose-down attitude; its pitch attitude decreased as it continued descending. The witness reported impact with the water in a 45° nose-down, wings-level attitude.
Personnel Information
The pilot had 14.5 hours of total flight experience in the accident airplane. A logbook entry indicated that while en route from Tampa's Peter O. Knight Airport to his home, he flew under the Skyway Bridge, which has a 180-ft vertical clearance over water. Recovered GPS data showed the pilot flew under the bridge on October 26, 2017. A few days later, the pilot stated on social media: "flying the Icon A5 over the water is like flying a fighter jet!"
Aircraft Information
The pilot accepted delivery of the airplane about 4 weeks before the accident. The airplane was equipped with an AOA indicator and a ballistic complete aircraft parachute (CAP) system. The Icon A5 Pilot's Operating Handbook indicated design maneuvering limits with flaps 0° and weight 1,510 pounds were +4 and -2 Gs (estimated takeoff weight was 1,476 pounds). Section 2.16 stated no restrictions on CAP system use, with optimal actuation from level flight above 500 ft AGL. Emergency procedures for loss of control included pulling the CAP handle and turning ignition off. The after cockpit entry checklist included removing and stowing the CAP safety pin.
The A5's stall characteristics were described: the airplane remains controllable up to 30° bank angles even when fully stalled. The AOA system uses static ports to measure pressure difference across the left wing near the leading edge. The AOA gauge has green, yellow, and red bands; the red band begins at 15.6°, indicating aerodynamic stall.
The A5 Sport Flying Operations manual discussed energy management at low altitude: energy is determined almost completely by airspeed; at low altitude the throttle is the only tool for maintaining or adding energy. It noted that 60-75 KIAS is the sweet spot for maneuvering, and below 60 KIAS the aircraft is more sluggish with less stall margin.
Wreckage and Impact Information
The airplane came to rest inverted in about 4 ft of water on a 192° heading. The empennage was separated and displaced forward of the wings. All major components were located at the scene. The front fuselage and cockpit were highly fragmented, with pieces scattered within a 300-ft radius. The CAP system was not deployed; the cockpit handle pin was in its installed position. The canopy was about 50 ft west of the wreckage with about 50% of the plexiglass missing. The left seat was separated; the pilot's three-point harness was anchored securely with the inertia reel intact and operable, but webbing exhibited fraying about 12 inches from the reel. The buckle operated normally.
The wings, wing tips, and nose section showed symmetrical fragmentation consistent with a wings-level impact. Both wings were attached and locked. Control continuity was established from cockpit to elevator and rudder through overload separations. Aileron continuity was established; flaps and flap handle were retracted. The fuel tank cap was secure, the tank was breached by the engine throttle cable, and no fuel was present. The engine remained attached, and manual rotation established continuity and compression for each cylinder. The propeller remained attached. No preaccident anomalies were noted with the airframe or engine that would have precluded normal operation.
Medical and Pathological Information
The Office of the Medical Examiner performed an autopsy; cause of death was blunt trauma with drowning as a contributory condition. Toxicology testing identified several drugs in cardiac blood and urine: Zolpidem (0.088 µg/ml), Amphetamine (2.2 µg/ml), Morphine (0.192 µg/ml), Fluoxetine (0.984 µg/ml) and norfluoxetine (1.569 µg/ml), Baclofen (0.72 µg/ml). Hydromorphone was found in urine. Ibuprofen was also found in urine. No ethanol was detected. Review of available medical records indicated a history of substance abuse requiring inpatient rehabilitation twice between 2013 and early 2015, and diagnoses of chronic back pain, insomnia, and depression treated with various medications. Records for 2016 and 2017 were not available.
Tests and Research
An airplane performance study used data from the DAC and engine control unit. The last second of data was excluded due to unreliable GPS altitude. The study identified three maneuvers. At 1201:19, a rapid climbing S turn from 0 to 134 ft and descent to 36 ft, max load factor 1.94 Gs, max AOA 7.53°. At 1202:29, a climbing right 360° turn from 19 to 136 ft, max load factor 1.93 Gs, max AOA 15.73° (within the red band). At 1203:34, a final climbing right turn from 210 ft and 81 knots, load factor increased to 1.91 Gs then varied, AOA increased to 15° (top of yellow band). About 3 seconds later, the throttle lever was retarded from 99% to 27%, engine speed decreased from 5,393 to 2,261 rpm. The lowest airspeed was 54 knots at the apex (358 ft) with low energy state. Computed bank angle exceeded 50° and pitch angle exceeded 30° before descent.
A feather study of ten samples from wreckage found feathers in two samples, but no avian DNA. No impact damage consistent with a bird strike was observed.
Additional Information
Title 14 CFR 91.119 requires minimum safe altitudes: over other than congested areas, not below 500 ft except over open water or sparsely populated areas, where aircraft may not be operated closer than 500 ft to any person, vessel, vehicle, or structure.
On May 8, 2017, a previous Icon A5 accident near Lake Berryessa, California, resulted in fatal injuries to the pilot and passenger. The NTSB determined the probable cause was the pilot's failure to maintain clearance from terrain while maneuvering at low altitude, with contributing factors. As a result, Icon Aircraft issued "Low Altitude Flying Guidelines" on October 23, 2017, distributed to A5 clients and owners. The guidelines reiterated minimum safe altitudes and provided maneuvering limits: above 300 ft agl ("Soft Deck") normal maneuvering with ±60° bank and ±30° pitch; below 300 ft agl benign maneuvering with ±45° bank and ±10° pitch. The guidelines also warned "Do not show off." The accident pilot was reported to have received and reviewed the guidelines.