48 Years ago today: On 9 December 1971 an Indian Airlines HAL-748 crashed at Chinnamanur, killing 21 out of 31 occupants (1st HAL-748 write-off).

Date: Thursday 9 December 1971
Time: 12:25
Type:
Hindustan Aeronautics Ltd. HAL-748-224 Srs. 2
Operator: Indian Airlines
Registration: VT-DXG
C/n / msn: 512
First flight: 1968-01-02 (3 years 11 months)
Crew: Fatalities: 4 / Occupants: 4
Passengers: Fatalities: 17 / Occupants: 27
Total: Fatalities: 21 / Occupants: 31
Aircraft damage: Destroyed
Aircraft fate: Written off (damaged beyond repair)
Location: near Cumbum (   India)
Crash site elevation: 1585 m (5200 feet) amsl
Phase: En route (ENR)
Nature: Domestic Scheduled Passenger
Departure airport: Trivandrum Airport (TRV/VOTV), India
Destination airport: Madurai Airport (IXM/VOMD), India

Narrative:
The aircraft strayed off course and collided with a hill in the Meghamalai hills, at an altitude of 5200 feet, 29 miles left off its desired track.