Flight History
On February 5, 2014, at approximately 0015 central standard time, an Embraer 145EP (EMB-145), registration N802HK, operating as Trans States Airlines flight 3395, was landing on runway 36R at Memphis International Airport (MEM), Memphis, Tennessee. During the landing, the airplane suddenly rolled to the right, and the right wing struck the runway. The 44 passengers and crew on board were not injured, and the airplane sustained substantial damage. The flight was operating under 14 CFR Part 121 as a scheduled passenger flight from Houston International Airport (IAH) to MEM. Instrument meteorological conditions prevailed.
The first officer was the pilot flying, and the captain was the pilot monitoring. The preflight inspection was routine, and the anti-ice system was not tested. The departure, climb, and cruise were uneventful. During descent, the airplane entered a cloud layer at about 3,500 ft mean sea level. Air traffic control vectored the flight for an ILS approach to runway 36L. Before reaching the final approach fix (FAF), the crew received intermittent localizer course indications. They executed a missed approach. During the go-around, the airplane spent additional time at altitudes with an increased probability of icing.
The crew then vectored to an ILS approach to runway 36R. While level at 2,000 ft, the flight entered clouds. The first officer noticed moisture on the windshield wiper and something on the windshield. The cockpit voice recorder captured the first officer asking about ice, and the captain replied, "a little bit." The airplane's ice protection system was in automatic mode and did not activate; the crew did not manually activate it. The crew reported no ice detection messages on the EICAS.
At the FAF, the localizer signal was uninterrupted. The approach was stabilized with landing gear down and flaps at 45°. Near approach minimums (about 400 ft agl), the airplane exited clouds, and the crew observed the runway. The airspeed reduced to 130 kts. The autopilot was disconnected at about 300 ft. After disconnection, repeated "autopilot" audio messages occurred; the crew attempted to silence them. The captain warned the first officer about speed; the first officer corrected. At about 20-40 ft agl, a rapid roll to the right occurred, followed by stick shaker activation. One angle-of-attack sensor reached 15°, indicated airspeed was 113 kts, and the maximum roll attitude was 28° right wing down. The wing struck the runway, and the airplane landed hard on the right side. The crew believed the roll was caused by a rudder hardover, but flight data recorder evidence did not show a large rudder deflection.
About 40 minutes after landing, the crew observed ice on the wings, horizontal stabilizer, and both engine inlets. The first officer reported the airplane covered in ice; the captain noted "a lot of ice" on the wing leading edge.
Crew Information
All crewmembers were current and qualified. The captain, hired in August 2005, held an Airline Transport Pilot certificate and had 6,400 total flight hours, with about 5,600 in the Embraer 145. He was on the first day of a 5-day reserve period; the accident was his fourth leg. He reported normal sleep and felt rested.
The first officer, hired in September 2012, held an Airline Transport Pilot certificate and had 930 flight hours as second in command in the Embraer 145. The accident was her third leg. She reported adequate rest.
Aircraft Systems
The Embraer 145 is equipped with an ice detection system comprising two independent detectors. When ice is detected, an "ICE CONDITION" advisory message appears on the EICAS, and the anti-ice valves open automatically. The system can also be manually activated via the OVERRIDE knob. The airplane's ice protection system heats critical surfaces using bleed air or electrical power. The wing inspection lights illuminate the wing leading edge, but evaluations showed that only about the last 3 ft of the leading edge is visible from the cockpit during darkness.
Weather
At the time of the accident, the reported weather at MEM included wind from 280° at 10 kts, tower visibility 1/2 mile, ceiling overcast at 400 ft agl, temperature 1°C, dew point -1°C. Icing charts from the National Center for Atmospheric Research indicated a 50-70% probability of trace to light icing between 1,000 and 2,000 ft agl at 0000, increasing to 85% probability of light icing below 3,000 ft agl at 0100.
Postaccident Examination
The airplane sustained damage to the right wing at rib 25R and wing spar 25R, including a gusset, lower skin, splice plate, and wing spar. The left and right ice detectors were removed and functionally tested; both passed all tests but exhibited slightly lower sensing mode frequencies, which the manufacturer stated would cause the unit to sense ice sooner. No other anomalies were found.
Postaccident Actions
On February 7, 2014, Trans States Airlines issued an urgent safety bulletin titled "Automatic Anti-Ice Monitoring," discussing the incident under investigation.