Gaganyaan TV-D1: ISRO Identifies Reason Behind Launch Hold, Reschedules Mission For Later Today. Know The Timing

Gaganyaan TV-D1: The launch of the Test Vehicle Development Flight (TV-D1) has been scheduled for 10:00 am IST on October 21, 2023, ISRO said in a mission update.

Gaganyaan TV-D1, also known as the Flight Test Vehicle Abort Mission-1, will demonstrate the performance of the Crew Escape System. It is the first uncrewed flight test of the Gaganyaan programme.  ( Image Source :X/@ISRO )

Gaganyaan TV-D1: The Indian Space Research Organisation (ISRO) has identified the reason behind holding the launch of the first development flight test of the Gaganyaan programme. The launch of the Test Vehicle Development Flight (TV-D1) has been scheduled for 10:00 am IST on October 21, 2023, ISRO said in a mission update. Gaganyaan TV-D1, also known as the Flight Test Vehicle Abort Mission-1, will demonstrate the performance of the Crew Escape System. It is the first uncrewed flight test of the Gaganyaan programme. 

This is the third time the mission has been rescheduled in a single day. Originally slated for launch at 8:00 am IST on October 21, the mission was rescheduled for launch at 8:30 am, and then 8:45 am. However, the launch was put on hold due to certain reasons, and ISRO Chief S Somanath said that the space agency would soon return with an update. 

Reason for the launch hold is identified and corrected.

The launch is planned at 10:00 Hrs. today.

— ISRO (@isro) October 21, 2023

As part of the Gaganyaan TV-D1 mission, an in-flight abort of the Crew Escape System will be demonstrated. This means that while the Crew Module is in the air, the Crew Escape System will be jettisoned, so that ISRO will be able to check certain flight parameters, and whether the Crew Escape System can be effectively separated from the Crew Module to save the lives of astronauts during crewed missions in case a mishap occurs. ISRO aims to conduct more test flight missions in the future.

The TV-D1 mission will be aborted at Mach number 1.2. Mach number refers to the ratio of the velocity of an object to the velocity of sound in the surrounding medium. This parameter has been named after Austrian physicist and philosopher Ernst Mach. The fact that the Crew Escape System will be jettisoned at Mach number 1.2 means that at that time, the velocity of the Crew Module has to be 1.2 times the velocity of sound in air.