IAI 1125 Astra

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. The airplane was destroyed by impact forces and a post crash fire and all five occupants were killed. Passengers were SkyJet Elite’s CEO with wife and child.
Crew:
Claudio Colmenares, pilot,
Gagan Reddy, copilot.
Passengers:
Alfredo Diez,
Kseniia Shanina,
Nicholas Diez.

According to the flight crew, the airplane touched down within the touchdown zone. The pilot reported that he applied the brakes and deployed the thrust reversers (TRs), but the brakes “were not grabbing.” The pilot released and reapplied brake pressure with no effect and advised the co-pilot he had no brakes. The co-pilot applied his brakes with no effect. The pilot selected the emergency brake handle and applied emergency braking. The emergency braking produced some slowing, and with the airplane’s nose wheel tiller, the pilot attempted a left turn to exit the runway onto a 45° taxiway, which he thought provided additional stopping distance; however, the airplane slid off the taxiway and into the adjacent grass. The right main landing gear collapsed, and the air plane came to rest upright, resulting in substantial damage to the right wing spar. Examination and testing of the airplane systems did not reveal any evidence of preimpact mechanical malfunctions with the wheel brakes or any other systems. Video evidence and recorded airplane data revealed the TRs were not deployed during the landing sequence. The cockpit voice recorder was overwritten during postaccident maintenance actions, and the accident flight communications were not available. Landing simulations based on available data were consistent with reduced deceleration during the landing roll; however, the simulations could not determine if the airbrakes were stowed or extended during the landing, and the airplane was not equipped with a flight data recorder, which could have captured airbrake deployment and position. Landing performance calculations showed that, without ground airbrakes, the landing ground roll distance exceeded the runway available from the airplane’s touchdown point. Tire skid marks indicated that heavy wheel braking occurred on the runway and taxiway surfaces. Based on the available information, the reason for the flight crew’s reported loss of braking effectiveness during landing could not be determined.