Discuss how the Hub & Spoke model can help India emerge as a global aviation transit hub. Examine associated infrastructural and regulatory challenges.

The Hub & Spoke model consolidates traffic from smaller "spoke" cities into major "hub" airports for onward international connections, with check-in, immigration and baggage check-through completed at the spoke itself [1]. Launched from Ahmedabad, it marks India's attempt to shift from an end-destination market to a global transit hub [1].

How it advances India's transit-hub ambition

• Captures leaked traffic: a substantial share of Indian international transfer traffic is presently routed through foreign hubs like Dubai, Singapore and London; consolidation lets Indian airports retain it [1].
• Seamless passenger experience: baggage moves airside at the hub without passenger intervention, and inbound customs/immigration shift to the spoke of final entry — removing the re-check burden that pushes flyers abroad [1].
• Monetises the spoke network: Modified UDAN (₹28,840 crore, 100 new airports and 200 helipads) supplies the feeder base the model depends on [2].
• Policy continuity: fulfils NCAP 2016's goal of making India an aviation hub of choice through connectivity, ease of doing business and cargo–MRO growth [3].

Infrastructural challenges

• Hub airports need transfer-specific capacity — dedicated corridors, automated baggage systems and slot headroom — beyond existing terminal expansion.
• Spoke airports require CIQ (customs–immigration–quarantine) facilities, absent at most UDAN airfields [2].
• Financing depends on sustained private participation, as under the PPP leasing of Ahmedabad, Jaipur, Lucknow and other AAI airports [4].

Regulatory challenges

• Combination flights are barred; separate aircraft for domestic and international legs raise costs and complicate scheduling [1].
• Inter-agency coordination among DGCA, BCAS, immigration and airport operators for security clearance at the spoke.
• Bilateral air service rights and fifth-freedom access must be renegotiated to attract genuine foreign transit traffic.

The model is therefore necessary but not sufficient: hub status will follow only if capacity creation, CIQ decentralisation and regulatory simplification advance together. Sequencing spoke-airport upgrades under Modified UDAN with hub-side transfer infrastructure can make India a competitive aviation gateway, realising NCAP 2016's vision of affordable, world-class connectivity.