VFR into IMC · NTSB ERA15FA144
MOONEY M20F — Norfolk, VA
| Date | March 4, 2015 |
| Location | Norfolk, VA |
| Aircraft | MOONEY M20F |
| Purpose of flight | Personal |
| Conditions | Night/Dark · Instrument Meteorological Cond |
| Phase / occurrence | Prior to flight Preflight or dispatch event |
| Pilot age | 61 |
| Pilot total time | 1,160 hrs · Experienced |
| Time in type | Unknown |
| Fatalities | 3 |
Probable cause
NTSB findings
- Aircraft-Aircraft oper/perf/capability-Performance/control parameters-Descent/approach/glide path-Not attained/maintained - C
- Personnel issues-Task performance-Use of equip/info-Aircraft control-Pilot - C
- Personnel issues-Action/decision-Info processing/decision-Decision making/judgment-Pilot - F
- Personnel issues-Task performance-Planning/preparation-Flight planning/navigation-Pilot - F
- Environmental issues-Conditions/weather/phenomena-Light condition-Dark-Effect on personnel - F
- Environmental issues-Conditions/weather/phenomena-Turbulence-(general)-Effect on operation - F
- Environmental issues-Conditions/weather/phenomena-Ceiling/visibility/precip-Low ceiling-Effect on operation - F
- Aircraft-Aircraft systems-Navigation system-(general)-Not specified
What happened
In preparation for the night cross-country flight from southern Florida to Virginia, the private pilot contacted flight service to file instrument flight rules (IFR) flight plans for each of the two planned legs. The pilot was advised that instrument meteorological conditions (IMC), moderate turbulence, and possible low-level wind shear would prevail for the second leg of the trip (the accident flight). Although the pilot indicated to the briefer that he was aware of these conditions, the extent to which he had familiarized himself with the forecast weather could not be determined because there was no record of a complete weather briefing from an official, access-controlled source.
The first leg of the flight departed about 2030 and landed uneventfully about 2240. After obtaining fuel, the pilot and his two passengers departed on the accident flight about 2353. The airplane reached the destination airport about 0300. The airport was under low IFR weather conditions, and the pilot requested an RNAV GPS instrument approach, even though the airplane was only equipped with a handheld GPS receiver. During the approach, the air traffic controller twice noted that the pilot was having difficulty maintaining alignment with the final approach course. When asked about this by the controller, the pilot first attributed the issue to problems displaying the instrument approach charts on his GPS receiver and second to the wind correction angle necessary to hold the course. At the conclusion of the unsuccessful approach, the pilot failed to comply with the published missed approach procedure and descended to an estimated 100 ft above ground level (agl) before subsequently climbing. When asked by the controller to fly the published missed approach procedure, the pilot responded that he was unable to do so because he was "off course."
With the assistance of air traffic controllers, the pilot diverted to a nearby airport equipped with an instrument landing system (ILS) even though similar weather conditions prevailed. The pilot was provided radar vectors for an ILS approach, but he again had difficulty maintaining the approach's prescribed altitudes and courses, and the controller cancelled the approach clearance. About 0400, during the pilot's second attempted approach to the diversion airport, the airplane descended to within 1 mile of the runway and about 200 ft agl. About that time, the pilot reported that he had the airport in sight, consistent with the airplane descending below the cloud ceiling. A plot of the airplane's GPS-derived ground track and the recorded air traffic control radio transmissions showed that, about the time the pilot reported the airport in sight, the airplane was about 1/4 mile offset from the localizer but tracking toward the runway. However, instead of continuing its track toward the runway, moments later, the airplane made an abrupt, 90-degree right turn before turning left back toward the approach runway several seconds later. During the final 9 seconds of the flight, the airplane descended at a calculated descent rate of 900 ft per minute to ground impact. The airplane's maneuvering and its final descent occurred over a relatively unlit area of water and forest. The diminished lighting conditions likely provided the pilot with limited external cues to draw from in his attempt to maintain control of the airplane and complete the visual portion of the landing approach.
Postaccident examination of the airframe and engine revealed no evidence of any preimpact mechanical malfunctions or failures. A technical performance assessment of the diversion airport's ILS equipment revealed no discrepancies associated with the systems in use by the pilot during the attempted approach.
Throughout the approaches to both airports, the pilot repeatedly described the extreme nature of the turbulence and the high wind velocity that the airplane was encountering. Forecast and observed weather were consistent with this assessment. The pilot also described that he was having difficulty maintaining a heading due to precession of the airplane's gyroscopic heading indicator. Detailed examination of the vacuum-system-driven gyroscopic heading indicator revealed no anomalies, and a functional test displayed no abnormal precession. It is most likely that the gyroscopic precession cited by the pilot was directly attributable to the turbulence.
The pilot's personal flight logs were not recovered, and neither his recent flight experience nor instrument flight currency could be determined; however, his inability to maintain assigned headings and altitudes and to fly navigational courses indicated that his level of proficiency in flying the airplane in IMC was inadequate for the flight, particularly given the extremely challenging nature of the weather conditions that prevailed on the night of the accident. Additionally, the pilot decided to conduct the flight using a handheld GPS receiver, which was not suitable for IFR navigation and instrument approaches.
Although toxicological testing revealed the presence of amphetamine in the pilot's blood and urine, the investigation was unable to determine whether the pilot's use of amphetamine or the effects of any underlying condition contributed to the accident.