Exactly 24 years ago today, on October 19, 1988, Indian Airlines Flight 113 crashed while on final approach to Ahmedabad Airport (AMD), killing 133 of the 135 people onboard.

The aircraft involved in the accident was a 17-year-old Boeing 737-200 registered VT-EAH. Delivered new to Indian Airlines in December 1970, the plane had accumulated 42,831 hours and 47,647 landings at the time of the crash.

Ahmedabad is 275 miles north of Mumbai

Indian Airlines flight 113 was a regularly scheduled domestic flight from Bombay (now known as Mumbai) to Ahmedabad, India. The aircraft took off from Bombay-Sahar International Airport (BOM) 20 minutes late at 06:05, piloted by Captain O.M. Dallaya and First Officer Deepak Nagpal.

Image: GCmaps

At 06:20, the crew contacted the tower at Ahmedabad Airport for a weather report after the visibility shrunk from 3.7 to 1.8 miles. At 06:32, the plane was told by Air Traffic Control (ATC) to descend to 15,000 feet and to report when they were at 1,700 feet over the Ahmedabad VHF omnidirectional range (VOR).

With visibility at 1.2 miles, the pilots decided to carry out a localiser-DME approach for runway 23. The pilots contacted ATC when they flew over the locator, which was the last radio contact with the plane.

The pilots never requested permission to land

The pilots never requested permission to land or gave standard call-outs when the plane reached an altitude of 1,000 feet. The cockpit voice recorder showed that both pilots were busy trying to spot the runway and lost track of the plane’s altitude. At 06:53 local time, the aircraft struck trees and an electricity pylon near Chiloda Kotarpur. The remains of the plane came to a halt 1.58 miles from the runway threshold.

The investigation

When speaking about the crash, the Airport Authority said that it was standard practice for the pilots to be able to see the runway from an altitude of 500 feet. They were not to descend further if they could not see the runway.

The Airport Authority noted that the VOR had to be operational at the time of the crash as the pilots had used it to make their turns. They also pointed out that the plane was lined up with the runway’s center when it struck the trees. Data collected from the aircraft’s flight recorders show that the altimeter was working correctly, which means they either ignored it or did not remain aware of the plane’s altitude.

It was also noted that despite the worsening visibility, controllers in the tower did not make Runway Visual Range measurements and report these to the pilots as they were supposed to do.

Following a Court of Inquiry, it was concluded that the following factors were responsible for the crash of Indian Airlines Flight 113:

• A judgment error by the pilot in command, Captain O.M. Dallaya, and his co-pilot.
• Information on declining visibility at the airport not being passed on to the plane by the tower.

After reading the report, the Government of India asked the United States National Transportation Safety Board (NTSB) to evaluate the accident and make recommendations.