Incident Investigation Report of Yeti-Airlines Domestic Pvt. Ltd.
Twin Otter 9N-AFA on 20th April, 2008

1. Synopsis
On the 2oth of April 2008, a Twin Otter operated by Yeti Airlines bearing the registration number 9N-AFA enroute from Bharatpur to Kathmandu at 0745 UTC, reported a complete failure of navigation and communication equipment to Kathmandu Approach.

There were 3 crew and 19 pax onboard. The Captain reported that after takeoff from Bharatpur airport after approximately 12 minutes the crew noticed that they had lost all communication and navigation equipment like VOR, DME, RMI and GOS. They were maintaining a heading of 060 dgrees magnetic and an altitude of 7500 feet.

After some time, they could establish communication with 9N-AHY a jetstream aircraft from the same company. Coordination with 9N-AHY enabled them to climb to an altitude of 9500 ft. with permission from Kathmandu Approach.

Continuing on a heading of 060 degrees, they were picked up by Kathmandu radar at a distance of 12 miles North-West of Kathmandu. Communicating with Kathamndu Approach they were instructed to proceed on heading of 180 degrees which enabled them to enter Kathmandu valley from the North-West.

As per the Captain, radio Navigation equipment were still inoperable at the time of landing.

2. Investigation
The crew was interviewed and written statements were obtained both at Aviation Safety Department (ASD) and their head office.

3. Recommnedations
The company is advised to maintain strict maintenance schedules and rectify all reported electrical problems.