Tata Sons and Singapore Airlines (SIA) on Tuesday announced that they will merge Vistara into Air India, with a target to complete the process by March 2024 subject to regulatory approvals. Once that happens, Tata Sons will hold 74.9% stake in the AI-Vistara-AI Express-AirAsia India Pvt Ltd (AAIPL) combined entity and SIA the remaining 25.1% stake.