Charter
1975-MAR-31 · Boudhanath, Kathmandu, Nepal

Royal Nepal Airlines — Flight Charter

A Royal Nepal Airlines Pilatus PC-6 Turbo Porter crashed seconds after takeoff from Kathmandu when the pilot attempted to fly with a ground lock pin still securing one of the ailerons. The aircraft, carrying the wife and daughter of mountaineer Sir Edmund Hillary, failed to maintain controlled flight during the initial climb. The pilot requested an immediate emergency landing but was unable to complete the turn, crashing into a ditch in the Boudhanath area behind the northern end of the runway. All five occupants, including the pilot, two Sherpa family friends, and the family's dog, were killed.

Aircraft
Pilatus PC-6/B2-H2 Turbo Porter
Registration
9N-AAZ
Phase
Cause
Souls on Board
5
Fatalities
5
Origin → Dest
Tribhuvan International Airport (KTM), Kathmandu, Nepal → Phaplu Airport (PPL), Nepal
Report

Investigation Summary

The accident occurred during a chartered flight intended to transport Louise Hillary and her daughter Belinda to Phaplu, where Sir Edmund Hillary was overseeing the construction of a hospital. Investigation into the wreckage and pre-flight activities revealed that the pilot, Peter Shand, had arrived late to the airport and bypassed the standard external walk-around inspection. Consequently, he failed to notice that a mechanical ground lock pin remained inserted in one of the aircraft's ailerons. This pin physically restricted the movement of the primary flight control surfaces. Upon takeoff from Runway 20 in a southern direction, the pilot immediately realized the control deficiency and requested permission to land. During the attempt to return to the airfield, the pilot initiated a right-hand turn to head back toward the runway. However, the aircraft became uncontrollable due to the locked aileron, overshot the airfield perimeter, and plunged into a ditch behind the northern end of the runway where it caught fire.

Final Conclusions

The crash was caused by the pilot's failure to perform a pre-flight walk-around, which resulted in the aircraft taking off with a ground lock pin still in place on an aileron. This mechanical restriction made the aircraft unflyable during the critical initial climb phase.

Video Analysis

No video analysis linked for this case file yet.

Airframe & Maintenance

Airframe Hours
0

Systems & Failure Modes

i

Ailerons

Primary flight control surfaces that control the aircraft's roll. One aileron was physically immobilized by a ground lock pin.

i

Ground Lock Pin

A safety device used to secure control surfaces while the aircraft is parked to prevent wind damage; it must be removed before flight.

Interesting Facts

  • 01The aircraft was a Pilatus PC-6/B2-H2 Turbo Porter, MSN 727, manufactured in 1971.
  • 02The victims included Louise Hillary and Belinda Hillary, the wife and 16-year-old daughter of Sir Edmund Hillary.
  • 03The pilot, Peter Shand, reportedly skipped the pre-flight walk-around because he was running late.
  • 04A ground lock pin was found to have been left in place on one of the ailerons.
  • 05The family's dog also perished in the crash.
  • 06The aircraft was destroyed by the impact and subsequent fire.

Safety Actions & Advisories

Pre-flight Inspection Rigor

The accident highlighted the critical necessity of the 'Remove Before Flight' protocol and the mandatory nature of the pilot's external walk-around, regardless of schedule pressures.

Location

Boudhanath, Kathmandu, Nepal · 28.1667, 84.2500

Case File History

  1. New evidenceUpdated investigation summary and findings.

Related Cases

Case ID · royal-nepal-9n-aaz-1975Last updated · Filed

© 2026 TechBridge Software Co., Ltd. — BlackBoxWiki is an open aviation reference. Not affiliated with any aviation authority.