SHIMLA, July 30 — The plane crash at Kathabai in Mandi district in which five persons died has once again exposed the vulnerability of aerial flights on the Chandigarh-Bhuntar route to mishaps.

The towering Kamrunag mountain ranges, which have to be crossed over to enter the Kulu valley, are virtually becoming a graveyard of aircraft with as many as three mishaps in less than five years. The incidence of aircrash is quite high in view of the fact that air traffic in the region is very low. The first mishap occurred in 1995 when an aircraft of the Punjab Government crashed into the mountains at Kamrunag, killing 13 persons, including the Governor, Mr Surendra Nath. A year later an aeroplane of Archana Airlines crashed just after crossing the range in which nine persons lost their lives.

Incidentally, all three mishaps have taken place, during the peak rainy season when the high mountain ranges are engulfed in thick fog most of the time. According to sources in the Civil Aviation Ministry, the aircraft are required to fly at a minimum height of 12,000 ft while passing through the ranges. However, the norm is not followed strictly and at times, particularly when the area is under fog, an error of judgement could lead to mishap.

A pilot who has been flying on the route said on condition of anonymity that more often than not the crew members are not properly briefed about the route. At times the pilot also does not feel any need for detailed information about the route.

Proper briefing about the route was necessary for flights over high mountain ranges. In case of the Chandigarh-Bhuntar route the mountains rise rather abruptly beyond Sundernagar, surprising the pilot of a low-flying aircraft who gets no time and room for manoeuvring. Besides, the high ranges also snap radio contact with the Air Traffic Control units.

Since the planes have crashed into the mountains at a height of around 9500 ft, it is clear they were flying at a much lower altitude than prescribed. It was high time that the Civil Aviation Ministry authorities conducted a fresh survey to find a safer alternative route to enter the Kulu valley.

Meanwhile, all five bodies have been recovered from the site of the crash. The black box has also been found. The bodies were brought to Sundernagar for a post-mortem examination.

According to an eyewitness account, the aircraft hovered around in the Jhungi valley for quite sometime, apparently in a bid to gain height. It did manage to gain some height but it was not enough to clear the 10,000-ft-high Kathabai hill and crashed.