Crash of a De Havilland DHC-6 Twin Otter 300 near Sanosware: 22 killed

On 29 May 2022, Tara Air’s 9N-AET, Twin Otter (DHC-6/300) aircraft was scheduled for three flights on Pokhara-Jomsom-Pokhara sector. Tara Air had also filed flight plans for two additional Charter flights on the same sector. Among those five flights, four flights were to be conducted by a set of crews already positioned at Pokhara while the last flight was scheduled to be commanded by the PIC who had reached Pokhara from Kathmandu that very morning. Since Jomsom Airport was closed for operations due to bad weather, the PIC went to Tara Air crew camp and waited for the updates of weather improvement of Jomsom. After Jomsom Airport was open for operations at 0321 UTC, Tara Air operation decided to operate the first scheduled flight. However suspecting the next flight operation to Jomsom could not be operated, the original PIC assigned to the flight seated on board as a passenger to Jomsom for his scheduled business trip and the PIC assigned for the last flight took command. The Flight Plan was amended accordingly. At 0342 UTC, Summit Air’s 9N-AKZ, LET-410 took-off from Pokhara to Jomsom. At 0405 UTC, it reported an altitude of 12,500 ft and patches of cloud over Tatopani. At 0409 UTC, Summit Air’s second aircraft 9N-AMG, LET-410, took-off for Jomsom and subsequently, at 0410 UTC, 9N-AET of Tara Air (TRA197) took-off with 19 passengers and three crews on board. The Copilot had initially reported 3 crew and 18 passengers onboard to Pokhara Tower but later, revised the passenger figure was 19 prior to takeoff. 9N-AET was supposed to take-off before SMT 601 but the PIC seemed hesitant to commence the flight due to weather PIREP from 9N-AKZ that, the en-route weather was not favorable for VFR flights and critical around LETE and TATOPANI. All the crew members of TRA 197 and SMT 601 were in their respective cockpits and communicating with the preceding flight 9N-AKZ as well as with Pokhara tower for the updated information of en-route and destination weather. No flights had been conducted since morning and most of the passengers of Tara air and Summit Air were already at airport. In this situation it can be assumed that there was pressure to conduct flight from each angle. While listening to the CVR of TRA 197, it was observed that someone, either ground staff or some intimate passenger to the crew, advising strongly to the PIC to conduct the flight. Following the PIREP from 9NAKZ, both TRA197 and SMT 601 subsequently started their engines to commence the flights. The PIC of TRA 197 was still hesitant to conduct the flight for Jomsom even after the engine start and delayed the taxi as he was not yet convinced about the weather report received from preceding 9N-AKZ aircraft. In the meantime, SMT 601 lined up for departure to Jomsom. That was one of the most important pressure points to the PIC of TRA 197 to initiate departure. TRA 197 finally lined up and took off from Pokhara at 0410 UTC following the SMT 601 based on the en-route weather information (VMC) from 9N-AKZ, through Pokhara Tower. The en-route weather provided by Summit Air’s 9N-AKZ to Pokhara Tower and the crewmembers of TRA 197 and SMT 601 was not the same. Aircraft took off from Pokhara from runway 04 heading North. Tower instructed “report 5 DME northwest RW 04”. Then after departure at 90 climb power aircraft turned left to maintain a heading of 345 and planned to join heading 305 degree towards Ghodepani. After four minutes, TRA 197 reported, “Now on course…. 6000 climbing and ETA Jomsom 32” (0432 UTC). At 04:21 TRA 197 reported to Pokhara Tower as position approaching Ghodepani 12000 climbing for 12500. After 6 Seconds ATC Pokhara asked TRA 197, “confirm would like to change level and TRA 197 replied, “No Ma'am we have crossed Ghodepani and like to be on”. Pokhara Tower instructed, “Tara 197 contact Jomsom Tower 122.5” CVR recordings show that after TRA 197 crossed Ghodepani, the PIC was not comfortable with the en-route weather. However, the flight was continued following the advice of SMT 601. At 0426 UTC, TRA 197made the first contact with Jomsom AFS and reported its position to which Jomsom Tower conveyed the prevailing weather as “Wind South Westerly up to 30 kts, QNH 1019, Temp 18º”. The PIC of TRA 197 reconfirmed twice if the wind was maximum, up to 30 Kts and currently South Westerly-25kts. The crew was discussing about the bad weather being encountered and the PIC himself voiced his dissatisfaction about the behavior of other pilots who conduct VFR flights in such unfavorable weather. The CVR recordings reveal that the aircraft was encountering clouds and the PIC was trying his best to remain clear of the clouds. During the course of flight, TRA 197 hadn’t reported any abnormalities encountered and neither any technical defect on aircraft either to Jomsom tower or Pokhara Tower. As per CVR, PIC was searching for light and brighter areas and adamantly heading towards it. As per CVR and V2 tracker data, the aircraft was maintaining 12000 ft and was in a climbing attitude. During the continuous attempts of crew to avoid the clouds with Terrain Avoidance and Warning System [TAWS] inhibited, the aircraft met with an unfortunate CFIT accident into the rocky terrain at an altitude of 4050 meter AMSL at Sanusare Mountain, Thasang Rural Municipality, Mustang. As per V2 tracker, last position of 9N-AET was 7.7 nm SW of Jomsom Airport. The aircraft was completely destroyed by the impact and there were no survivors.