Crash of a Dornier DO228-101 in Bharatpur: 19 killed

Date & Time: Jul 31, 1993
Type of aircraft:
Operator:
Registration:
9N-ACL
Survivors:
No
Site:
Schedule:
Kathmandu - Bharatpur
MSN:
7029
YOM:
1984
Country:
Region:
Crew on board:
3
Crew fatalities:
Pax on board:
16
Pax fatalities:
Other fatalities:
Total fatalities:
19
Circumstances:
While descending to Bharatpur Airport, the crew encountered poor weather conditions. Too low, the aircraft struck the slope of a rocky peak located about 6,5 km short of runway 15 threshold. The aircraft was destroyed and all 19 occupants were killed.

Crash of an Airbus A300B4-203 in Kathmandu: 167 killed

Date & Time: Sep 28, 1992 at 1430 LT
Type of aircraft:
Operator:
Registration:
AP-BCP
Survivors:
No
Site:
Schedule:
Karachi - Kathmandu
MSN:
025
YOM:
1976
Flight number:
PK268
Country:
Region:
Crew on board:
19
Crew fatalities:
Pax on board:
148
Pax fatalities:
Other fatalities:
Total fatalities:
167
Captain / Total flying hours:
13186
Captain / Total hours on type:
6260.00
Copilot / Total flying hours:
5849
Copilot / Total hours on type:
1469
Aircraft flight hours:
39045
Aircraft flight cycles:
19172
Circumstances:
The ill-fated aircraft departed Karachi Airport Pakistan, at 0613 hours UTC on 28 September 1992 as Pakistan International Airlines Flight Number PK 268, a non-stop service to Kathmandu, Nepal. The accident occurred at 0845 UTC (1430 hours local time) when the aircraft struck a mountain during an instrument approach to Kathmandu’s Tribhuvan International Airport. The impact site was at an altitude of 7280 feet above sea level (2890 feet above airport level), 9.16 nautical miles from the VOR/DME beacon and directly beneath the instrument approach track from the VOR/DME beacon (9.76 nm from and 2970 ft above the threshold of Runway 02 which is 77 feet below the airport datum). The flight through Pakistani and Indian airspace appears to have proceeded normally. At 0825 hrs UTC (1410 hrs local time) two-way contact between Pakistan 268 and Kathmandu Area Control West was established on VHF radio and the aircraft was procedurally cleared towards Kathmandu in accordance with its flight plan. After obtaining the Kathmandu weather and airfield details, the aircraft was given traffic information and instructed to report overhead the SIM (Simara) non-directional beacon (214°R VOR/39 nm from Kathmandu’s KTM VOR/DME) at or above FL150 (flight level on standard altimeter) as cleared by the Calcutta Area Control Centre. At 08:37 hrs the copilot reported that the aircraft was approaching the SIM beacon at FL 150, whereupon procedural clearance was given to continue to position SIERRA (202°R/10 nm from the KTM beacon) and to descend to 11,500 feet altitude. No approach delay was forecast by the area controller and the co-pilot correctly read back both the clearance and the instruction to report at 25 DME. At 08:40:14 hrs, he reported that the aircraft was approaching 25 DME whereupon the crew were instructed to maintain 11,500 feet and change frequency to Kathmandu Tower. Two-way radio contact with the Tower was established a few seconds later and the crew reported that they were in the process of intercepting the final approach track of 022M (Magnetic) of Radial 202 KTM VOR ) They were instructed to expect a Sierra approach and to report at 16 DME. At 08:42:51 hrs the first officer reported “One six due at eleven thousand five hundred”. The tower controller responded by clearing the aircraft for the Sierra approach and instructing the crew to report at 10 DME. At 08:44:27 the first officer reported 10 DME and three seconds later he was asked, “Report your level”. He replied, “We crossed out of eight thousand five hun,’ two hundred now”. The controller replied with the instruction “Roger clear for final. Report four DME Runway zero two”. The copilot responded to this instruction in a normal, calm and unhurried tone of voice; his reply was the last transmission heard from the aircraft, thirty-two seconds after the copilot reported 10 DME the aircraft crashed into steep, cloud-covered mountainside at 7,280 feet amsl and 9.16 nm on radial 202 of KTM VOR. All 167 occupants were killed.
Probable cause:
The balance of evidence suggests that the primary cause of the accident was that one or both pilots consistently failed to follow the approach procedure and inadvertently adopted a profile which, at each DME fix, was one altitude step ahead and below the correct procedure. Why and how that happened could not be determined with certainty because there was no record of the crew's conversation on the flight deck. Contributory causal factors were thought to be the inevitable complexity of the approach and the associated approach chart.
The following findings were reported:
- The flight deck crew were properly licensed and medically fit,
- The aircraft had been properly maintained and was fit for the flight and the essential aircraft systems were operating normally during the approach,
- The SIERRA approach to Kathmandu is a demanding approach in any wide-bodied aircraft,
- Unlawful interference and extreme weather were not causal factors,
- The crash site was enveloped in cloud at the time of the accident,
- There was no ATC clearance error,
- The VOR DME beacons used for the approach were operating satisfactorily and there was no evidence of failure or malfunction within the aircraft’s DME equipment,
- The aircraft acquired and maintained the correct final approach track but began descent too early and then continued to descend in accordance with an altitude profile which was consistent with being 'one step ahead' and below the correct profile,
- At 16 DME the co-pilot mis-reported the aircraft’s altitude by 1,000 feet,
- The commander did not adhere to the airline’s recommended technique for the final part of the approach which commenced at 10 DME,
- The 10 DME position report requested by the Tower controller was made at an altitude below the minimum safe altitude for that portion of the approach,
- The altitude profile on the Jeppesen approach chart which should have been used by the pilots was technically correct. However, the profile illustrated could not be flown in the A300 at V app, in common with any other wide-bodied jet of similar size and the minimum altitude at some DME fixes was not directly associated with the fix,
- The aircraft did not have control column mounted chartboards,
- As described in the report, there is scope for improving the SIERRA approach procedure and its associated charts,
- Kathmandu was not a frequent destination for PIA’S A300 crews and neither pilot had operated that within the previous two months,
- PIA’s training of air crews, briefing material and self-briefing facilities for the SIERRA approach to Kathmandu leave room for improvement,
- PIA’s route checking and flight operations inspection procedures were ineffective,
- The accident was inevitable 15 seconds before impact,
- The Tower controller requested an altitude report immediately after the co-pilot reported at 10 DME. His failure to challenge the low altitude reported at 10 DME was a missed opportunity to prevent the accident but, even if he had done so, it is doubtful whether the accident could have been averted,
- Some air controllers at Kathmandu had a low-self-esteem and was reluctant to intervene in piloting matters such as terrain separation,
- The GPWS was probably serviceable but failed to warn the crew of impending flight towards high ground because of the combination of elderly equipment and rugged terrain,
- Advice within the aircraft manufacturer’s operating manuals regarding pilot reaction to a GPWS warning was incomplete,
- The MEL was being breached in that PIA wen not supplying their CAA with the required carry-forward defect summaries for analysis, neither was the CAA requesting them.

Crash of a Harbin Yunsunji Y-12-II in Lukla

Date & Time: Sep 26, 1992
Type of aircraft:
Operator:
Registration:
9N-ACI
Flight Phase:
Survivors:
Yes
Schedule:
Lukla - Kathmandu
MSN:
0069
YOM:
1992
Country:
Region:
Crew on board:
2
Crew fatalities:
Pax on board:
12
Pax fatalities:
Other fatalities:
Total fatalities:
0
Circumstances:
During the takeoff roll at Lukla-Tenzing-Hillary Airport, at a speed of 85 knots, the nose gear collapsed. Out of control, the aircraft veered off runway and came to rest in a ditch. All 14 occupants escaped uninjured while the aircraft was damaged beyond repair.
Probable cause:
It was determined that the nose gear tyre burst after hitting stones coming from a pothole in the runway surface. This caused the nose gear to collapse.

Crash of an Airbus A310-304 near Kathmandu: 113 killed

Date & Time: Jul 31, 1992 at 1245 LT
Type of aircraft:
Operator:
Registration:
HS-TID
Survivors:
No
Site:
Schedule:
Bangkok - Kathmandu
MSN:
438
YOM:
1987
Flight number:
TG311
Country:
Region:
Crew on board:
14
Crew fatalities:
Pax on board:
99
Pax fatalities:
Other fatalities:
Total fatalities:
113
Circumstances:
Thai Airways Flight 311 was conducting the Sierra (VOR/DME) approach to runway 02 at Tribhuvan International Airport, in instrument weather conditions. A flap fault occurred while the flight was on the approach; this caused the crew to ask for clearance back to Calcutta, a decision that was in keeping with both Company and performance requirements, which necessitate the use of full flaps for the steep final approach. Shortly (21 seconds) after making this request, at a distance of approximately 12 nm from the Kathmandu VOR, the flap fault was rectified by retracting and then reselecting the flaps. The crew determined that it was not possible to continue the straight-in approach, due to the steep descent angles required and the position of the aircraft. The crew stated to the control tower that they wished to start their approach again and requested a left turn back to the Romeo fix, which is 41 nm south south-west (202 radial) of the Kathmandu VOR. The Controller, in the non-radar environment, responded by clearing the flight to make the Sierra approach, which starts at the 202 radial and 16 nautical miles from the VOR. The crew response to the clearance was to report that, at the moment, they couldn't land and to ask again for left turn back to Romeo to start their approach again. After further dialogue with the controller, which included requests for a left turn, the crew unilaterally initiated a right turn from the aircraft's 025° heading and commenced a climb from an altitude of 10,500 feet to FL180, when the flight was about 7 nm south of the Kathmandu VOR. The crew reported to the tower controller that the flight was climbing and the controller replied by instructing the crew to report at 16 nm for the Sierra approach. During the turn, there was more discussion between the tower controller and the flight, where it was established that the aircraft was to maintain an altitude of FL115 and was to 'proceed to Romeo' and contact the Area Control Center (ACC) controller. The flight, commencing a descent while in the turn, completed a 360° turn, momentarily rolling out on headings of 045° and 340°, and again proceeded toward the north on a heading of 025° magnetic. When the flight was about 5 nm south-west of the Kathmandu VOR, the crew contacted the ACC and stated that the aircraft was 'heading 025' and they wished to proceed to Romeo to start their approach again; adding they had 'technical problems concerned with the flight.' It was again established that the flight was to proceed to Romeo and the crew agreed to 'report over Romeo.' It was determined from the cockpit voice recorder that the crew was in the process of inserting 'Romeo' and other related navigational information in the Flight Management System, but were experiencing difficulties. The flight continued towards the north on a heading of 025° and then, at about 16 nm north, the heading was altered to the left to 005°. Slightly over one minute later, the Ground Proximity Warning System (GPWS) sounded the warning 'terrain, terrain' followed by 'whoop whoop pull-up'; the aural warning continued until impact approximately 16 seconds later. Engine thrust was increasing and 'Level Change' had been announced on the cockpit, just before the impact occurred at the 11,500-foot level of a 16,000-foot peak; the accident site was located on the 015 radial (north-north east) at 23.3 nm from the Kathmandu VOR. The aircraft was destroyed and all 113 occupants were killed.
Probable cause:
TG311 flight crew's management of the aircraft flight path wherein the flight proceeded in a northerly direction which was opposite to the cleared point Romeo to the South; ineffective radio communication between the area control centre and the TG311 flight crew which allowed the flight to continue in the wrong direction, in that the TG311 crew never provided the aircraft's VOR radial when stating DME and the controller never solicited this information and thus the aircraft's position was not transmitted at any time; and ineffective cockpit crew coordination by the TG311 crew in conducting flight navigation duties. Contributing factors were: the misleading depiction of Romeo on the operator's approach chart used by the flight crew; a flap fault, although corrected, required that the initial approach be discontinued; and radio communication difficulties between the TG311 crew and the air traffic controllers that stemmed from language difficulties and ineffective discussion of apparent unresolved problems.

Crash of a De Havilland DHC-6 Twin Otter near Surkhet: 3 killed

Date & Time: Jul 10, 1991 at 1200 LT
Operator:
Registration:
RAN-26
Flight Phase:
Flight Type:
Survivors:
No
Site:
Schedule:
Surkhet - Jumla
MSN:
843
YOM:
1988
Location:
Country:
Region:
Crew on board:
3
Crew fatalities:
Pax on board:
0
Pax fatalities:
Other fatalities:
Total fatalities:
3
Circumstances:
Four minutes after his takeoff from Surkhet Airport, while climbing to an altitude of 5,800 feet, the captain informed ATC about good flight conditions and that he was leaving the valley shortly. A minute later, while flying in clouds, the aircraft struck the slope of a mountain (6,300 feet high) located few km from Surkhet Airport. The wreckage was found 500 feet below the summit and all three occupants were killed.
Probable cause:
Controlled flight into terrain following a wrong altimeter setting. It was determined that the crew departed Surkhet Airport under VFR mode but while climbing, he encountered limited visibility as the mountain struck by the aircraft was shrouded in clouds. At impact, the captain's altimeter showed 7,350 feet while the aircraft's real altitude was 5,800 feet.

Crash of a De Havilland DHC-6 Twin Otter in Simikot

Date & Time: Jun 20, 1991 at 1224 LT
Operator:
Registration:
9N-ABS
Flight Type:
Survivors:
Yes
Schedule:
Nepalgunj - Simikot
MSN:
795
YOM:
1982
Location:
Country:
Region:
Crew on board:
2
Crew fatalities:
Pax on board:
0
Pax fatalities:
Other fatalities:
Total fatalities:
0
Circumstances:
On final approach to Simikot Airport, the twin engine aircraft struck a tree and crashed 500 meters short of runway. Both pilots were injured.

Crash of a De Havilland DHC-6 Twin Otter 300 in Lukla

Date & Time: Jun 9, 1991 at 1010 LT
Operator:
Registration:
9N-ABA
Survivors:
Yes
Schedule:
Kathmandu - Lukla
MSN:
301
YOM:
1971
Country:
Region:
Crew on board:
3
Crew fatalities:
Pax on board:
14
Pax fatalities:
Other fatalities:
Total fatalities:
0
Circumstances:
While descending to Lukla Airport, weather conditions deteriorated and the captain decided to go-around and to follow a holding pattern. Few minutes later, as he thought weather conditions improved, he decided to attempt to land and initiated a second approach. On short final, the aircraft entered a layer of low clouds and the aircraft was not properly aligned when it struck the runway surface and bounced. Out of control, it veered off runway and came to rest in a ravine. All 17 occupants were injured and the aircraft was destroyed.

Crash of a Short SC.7 Skyvan 3 Variant 100 in Dhangadhi: 25 killed

Date & Time: Dec 30, 1985
Type of aircraft:
Operator:
Registration:
RAN-23
Flight Type:
Survivors:
No
Site:
Schedule:
Katmandu – Dhangadhi
MSN:
1978
YOM:
1982
Location:
Country:
Region:
Crew on board:
3
Crew fatalities:
Pax on board:
22
Pax fatalities:
Other fatalities:
Total fatalities:
25
Circumstances:
While approaching Dhangadhi Airport, the twin engine airplane crashed in unknown circumstances in a wooded area located on a mountain slope, few km from the airfield. All 25 occupants were killed.

Crash of a De Havilland DHC-6 Twin Otter 300 in Bhojpur: 15 killed

Date & Time: Dec 22, 1984
Operator:
Registration:
9N-ABH
Survivors:
Yes
Site:
Schedule:
Kathmandu - Bhojpur
MSN:
376
YOM:
1973
Location:
Country:
Region:
Crew on board:
3
Crew fatalities:
Pax on board:
20
Pax fatalities:
Other fatalities:
Total fatalities:
15
Circumstances:
While descending to Bhojpur in marginal weather conditions, the Twin Otter struck the slope of a mountain located few km from the airport. All three crew members and 12 passengers were killed while eight others were injured.
Probable cause:
It was determined that the crew initiated the descent prematurely, causing the aircraft to descend below the MDA.

Crash of a Pilatus PC-6 Turbo Porter in Biratnagar: 10 killed

Date & Time: Nov 19, 1981 at 1200 LT
Operator:
Registration:
9N-ABJ
Flight Phase:
Survivors:
No
Schedule:
Biratnagar - Kathmandu
MSN:
746
YOM:
1975
Location:
Country:
Region:
Crew on board:
1
Crew fatalities:
Pax on board:
9
Pax fatalities:
Other fatalities:
Total fatalities:
10
Circumstances:
After takeoff from Biratnagar Airport, while in initial climb, the single engine airplane lost height and crashed. All 10 occupants were killed.