- Location: Hot Springs, Virginia
- Accident Number: ERA24FA136
- Date & Time: March 10, 2024, 14:52 Local
- Registration: N1125A
- Aircraft: ISRAEL AIRCRAFT INDUSTRIES 1125 WESTWIND ASTRA
- Aircraft Damage: Destroyed
- Defining Event: Controlled flight into terr/obj (CFIT)
- Injuries: 5 Fatal
- Flight Conducted Under: Part 91: General aviation - Personal
https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/193906/pdf
https://data.ntsb.gov/Docket?ProjectID=193906
On March 10, 2024, about 1452 eastern daylight time, an Israel Aircraft Industries 1125 Westwind Astra, N1125A, was destroyed when it was involved in an accident near Hot Springs, Virginia. The airline transport pilot, commercial pilot, and three passengers were fatally injured. The airplane was operated by SkyJet Elite as a Title 14 Code of Federal Regulations (CFR) Part 91 personal flight.
Following an uneventful flight, the flight crew was descending the twin-engine business jet for landing at the destination airport, which was equipped with a 5,600-ft-long runway and located on a mountain ridge. Cockpit voice recorder (CVR) audio indicated that the pilot-in-command (PIC) was the pilot flying and the second-in-command (SIC) was the pilot monitoring. Air traffic control provided the crew with the local altimeter setting as they began their descent from cruise altitude about 24 minutes before the accident. About 12 minutes later, the crew informed the controller that they had obtained the weather information at the destination. Shortly thereafter, the controller cleared the crew direct to an intermediate fix on the intended instrument landing system (ILS) approach, instructing them to cross the fix at or above 6,100 ft mean sea level (msl). The crew acknowledged and began turning toward the final approach course. About two minutes later, the controller queried the crew about their altitude, stating that he observed the airplane at 5,900 ft msl. The crew responded that they were at the assigned altitude and continued the approach. Given that the CVR did not record the crew performing any crosscheck or verification of the altimeter settings as they descended, nor did it capture the crew conducting an approach briefing, the controller’s observation that the airplane 200 ft lower than its assigned altitude suggests that the crew did not reset the airplane’s altimeter setting during the descent.
As the crew descended toward the final approach fix, the SIC asked the PIC if he would like the airplane’s flight guidance system (FGS) set to vertical speed (VS) mode, which the PIC confirmed. In this mode, the airplane’s autopilot would maintain a specified descent rate set by the crew, and would continue to descend to the set altitude at the specified rate of descent regardless of the airplane’s position on the glideslope. As the airplane neared the final approach course, the SIC stated that FLOC was captured on both sides. This likely referenced a flight management system (FMS)-generated final approach course based on the waypoints that had been programmed into the system, rather than the localizer signal broadcast by the ILS. If the ILS frequency had been tuned and selected as the navigation source, the display should have indicated LOC, not FLOC.
About 7 miles from the runway threshold (about 3 minutes before the accident), the crew began to configure the airplane for landing. The PIC stated that he had the airport in sight, and shortly thereafter, the SIC confirmed that he also had the airport in sight. Upon crossing the final approach fix, the PIC began a descent and the SIC extended the landing gear. There was no mention of a change in autopilot mode, and it is likely that this descent was also performed in VS mode. The PIC called for the before landing checklist, which the SIC completed, concluding the checklist by reporting to the PIC that the airplane was below glideslope. About 1.5 nautical miles (nm) from the runway, the SIC reported full deflection below glideslope.
Shortly thereafter, the SIC announced that the airplane was 15 knots above reference speed. About 30 seconds before the accident, the PIC turned the autopilot off. Shortly after the automated Enhanced Ground Proximity Warning System (EGPWS) 1,000-ft annunciation, the SIC suggested a go-around; the PIC did not respond. The SIC again called for a go-around just before the EGPWS 500-ft annunciation; again, the PIC did not respond. About 3 seconds later, the airplane impacted rising terrain about 300 ft before the runway threshold.
Based on the SIC’s statement that FLOC was displayed, it is likely that the flight crew did not arm the approach on either the FMS or FGS, and as a result, the system did not automatically tune the ILS frequency or capture the glideslope. Alternatively, the flight crew could have manually tuned and verified the ILS frequency on the ILS receiver. The flight crew was likely seeing advisory lateral and vertical guidance on the flight instruments based on the waypoints and altitudes input into the FMS; however, to obtain glideslope vertical guidance, the ILS frequency would need to be tuned and selected, and approach mode would need to be armed. Additionally, given the crew’s failure to properly set the altimeter, the SIC’s programming of the autopilot in VS mode to a final altitude of 4,100 ft would have resulted in the airplane descending to a true altitude between 3,800 ft and 3,900 ft before the autopilot would attempt to maintain altitude. The airport was located at an elevation about 3,792 ft msl.
The airplane’s EGPWS was capable of producing an aural “Glideslope” alert for a deviation in excess of 1.3 dots fly up (as depicted by a glideslope needle deflection of 1.3 dots above the cockpit glideslope indicator’s centerline) if the ILS was tuned and providing deviation information to the EGPWS. The accident airplane deviated beyond 1.3 dots fly up multiple times with no glideslope aural alert heard on the CVR. The EGPWS was also capable of producing radio altitude callouts for non-precision approaches and a review of the CVR found three of these callouts were heard, at 2,500 ft, 1,000 ft, and 500 ft. Based on the lack of a “Glideslope” aural alert, it is likely that the ILS was not tuned. Therefore, the flight instruments would not have received or displayed lateral localizer or vertical glideslope deviation information and the EGPWS would not have the required inputs to provide the aural “Glideslope” alert.
A review of the data recovered from the airplane’s EGPWS unit revealed that the software was not updated in accordance with an FAA special airworthiness information bulletin (SAIB) applicable to the accident airplane, nor had the EGPWS been wired directly into the airplane’s GPS as specified in the SAIB. Had the operator completed these actions, it is likely that, based on the accident flight path, the flight crew would have received an EGPWS “too low terrain” aural alert about one mile from the end of the runway, which may have prompted the PIC to take corrective action.
The PIC obtained his type rating in the accident airplane make and model about two months before the accident. A review of his training records found that multiple instructors had listed flight management system (FMS) use as one of the pilot’s weaknesses. About six months before the accident, the PIC had been dismissed from another operator due to his lack of adherence to SOPs, poor CRM, poor checklist usage, inability to manage the FMS, and poor aircraft control.
The accident airplane operator’s stabilized approach policy required that a missed approach or go-around be initiated immediately upon an approach becoming unstable below 1,000 ft above airport elevation when in instrument meteorological conditions and below 500 ft when in visual meteorological conditions. During the approach, the PIC exceeded multiple criteria that should have resulted in a missed approach or go-around, including reference speed, glideslope deviation, and descent rate parameters.
Snow showers were reported in the area around the time of the accident; however, the crew reported the airport in sight about two minutes before the accident and the CVR recording did not subsequently indicate that they lost sight of the runway. Therefore, it is likely that they remained in visual contact with the airport throughout the final portion of the approach. The wind conditions at the time of the accident were conducive to updrafts and downdrafts. It is likely that the crew encountered these conditions during the accident approach, which may have contributed to the airplane’s deviation from stabilized approach criteria and its subsequent impact with terrain; however, the PIC had ample time to complete a go-around or missed approach if he had initiated it when the approach became unstabilized. Instead, the PIC chose to continue the approach in challenging wind conditions despite exceeding multiple stabilized approach parameters.
Finally, the operator’s policy dictated that all pilots would incorporate crew resource management (CRM) considerations and practices into all aspects of flight operations. A vital CRM practice is for either crew member to be able to call for a go-around and for the pilot flying to immediately initiate the maneuver. The SIC made multiple references to the approach being unstable and twice called for a go-around. It is possible that the accident could have been prevented if the PIC had immediately initiated a go-around when the go-around call was made by the SIC.
- Probable Cause: The PIC’s continuation of an unstabilized approach in gusting wind conditions and his failure to monitor the airplane’s altitude during the approach, which led to a descent into terrain short of the runway. Contributing was the flight crew’s failure to set the appropriate altimeter setting and failure to properly configure the avionics for the ILS approach.
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