- Why in news
- On 6 April 2026, the Ministry of Railways approved projects worth ₹1,364.45 crore for Kavach, optical fibre backbone and electronic interlocking across Southern, Northern, North Central and South Central Railway zones.
- What it is
- Kavach is India's indigenously developed Automatic Train Protection system. It uses on-board equipment, trackside devices and radio communication to help a train stop automatically if the driver fails to act, and to prevent collisions. It was developed by the Research Designs and Standards Organisation (RDSO) with Indian industry partners.
- Kavach umbrella work
- The work is part of an umbrella programme to provide Kavach with an LTE communication backbone on balance routes, costing ₹27,693 crore in the 2024-25 Pink Book.
- Electronic interlocking
- Panel interlocking will be replaced at 35 stations in Guntakal Division and 14 in Nanded Division of South Central Railway, on HDN/HUN routes.
- Developer of Kavach
- Kavach was developed indigenously by RDSO, the Railways' research and standards body, with Indian industry.
- Safety level
- Kavach needs the highest safety certification, SIL-4.
- Adoption
- Kavach became the National ATP system in July 2020.
- Version 4.0 upgrades
- Better location accuracy, better signal aspect information in big yards, station-to-station Kavach interface on OFC, and direct interface with Electronic Interlocking.
- Components
- Implementation needs station Kavach, RFID tags along the track, telecom towers, optical fibre cable and loco Kavach.
- Trackside coverage
- Trackside work is taken up on 24,427 RKm covering Golden Quadrilateral, Golden Diagonal, high density network and identified sections.
- Sections commissioned
- Vadodara–Virar (344 km, Western Railway), Tuglakabad Junction Cabin–Palwal (35 km, Northern Railway) and Manpur–Sarmatanr (93.3 km, East Central Railway).
- Technologies used
- Kavach combines microprocessors, GPS and radio communication; it alerts the loco pilot and applies brakes automatically if needed.
- Protections offered
- Protects against Signal Passing at Danger (SPAD), side, head-on and rear-end collisions, overspeeding, and gives level crossing gate information.
- Developer
- Kavach was developed by RDSO, the research and standards body of Indian Railways under the Ministry of Railways.
Don’t confuse with Electronic interlocking vs Kavach: Interlocking prevents conflicting signals and routes at stations. Kavach is an on-board and trackside system that controls train speed and braking.
Don’t confuse with Kavach vs ABS/CTC: Automatic Block Signalling (ABS) and Centralised Traffic Control (CTC) manage train movement and line capacity. Kavach adds automatic collision protection.
Don’t confuse with Kavach vs Electronic Interlocking: Interlocking controls points and signals at stations to prevent conflicting moves. Kavach is an ATP system that brakes the train itself.
Don’t confuse with Kavach vs TCAS: TCAS (Train Collision Avoidance System) was the earlier name for Kavach in trials; do not confuse it with the aircraft system of the same acronym.
Science and technology: 57 Prelims questions since 2013; most test the concept behind the news, not the news itself. In Mains, 12 news-triggered questions.
Why it matters
- Kavach reduces collisions caused by signal passed at danger and human error.
- A fibre backbone and electronic interlocking give reliable communication and cut manual intervention, supporting high-density routes.
- Reduces accidents from human error such as signal passing.
- Indigenous SIL-4 technology supports self-reliance in rail safety.
- Improves rail safety by preventing collisions and overspeeding even in low visibility.
- Promotes self-reliance and the Indian signalling industry.
Problems
- Fitting Kavach on thousands of locomotives and thousands of route km is costly and slow.
- It needs reliable telecom, fibre and interlocking first, so works must be coordinated across zones.
- Heavy cost: about Rs 50 lakh per km trackside and Rs 80 lakh per loco.
- Deployment is slow: 1,452 RKm commissioned against 24,427 RKm taken up.
- Large network to cover and locomotives to fit, so rollout is slow and costly.
- Needs integration with existing signalling and interlocking systems and trained staff.
Way forward
- Complete the fibre and interlocking groundwork before or with Kavach rollout, prioritising high-density routes.
- Track progress and fund works on a time-bound basis.
- Speed up OFC, tower and loco fitment, and train more staff.
- Prioritise high-density routes, then extend to the wider network.
- Prioritise high-density routes and fit locomotives in step with track installation.
- Keep independent safety assessment and ongoing upgrades based on operational feedback.
Put in your answer
Kavach 4.0 locomotive allocation: ₹208.81 crore for 232 locomotives in Southern Railway shows the scale of fitment cost.
Electronic interlocking umbrella work: A ₹15,164 crore umbrella work covers electronic interlocking at balance stations on HDN/HUN routes where Kavach/ABS/CTC is sanctioned.
Cost: Trackside and station equipment cost about Rs 50 lakh per km; loco equipment about Rs 80 lakh per loco.
Kavach 4.0 coverage: 1,306.3 route km of Kavach 4.0 commissioned across five zones after this addition.
Head-on collision test: On Manpur–Sarmatanr, a head-on collision test saw the train stop automatically, validating the system.
UPSC’s own questions that come close to this issue, from our Prelims and Mains banks.
Prelims practice · Single answer
Ours, not from a UPSC paper
Consider the following statements about Kavach, India's Automatic Train Protection system: 1. It requires safety certification of the highest order, SIL-4. 2. It was adopted as the National ATP system in July 2016. 3. Kavach specification version 4.0 was approved by the Commission of Railway Safety. 4. Version 4.0 provides a direct interface to the existing Electronic Interlocking System. How many of the above statements are correct?
How many of the above statements are correct?
True or false?
1 of 11
Statements the way Prelims prints them. Say first, then see the fact.
1.Kavach is an indigenously developed Automatic Train Protection system.
True. Kavach is an indigenous ATP system.
2.Kavach requires safety certification of the highest order, SIL-4.
True. It requires SIL-4 certification.
3.Kavach applies brakes automatically if the Loco Pilot fails to keep the train within speed limits.
True. It applies brakes automatically when the loco pilot fails to do so.
4.Kavach specification version 4.0 was approved by the Commission of Railway Safety.
False. RDSO approved version 4.0.
5.Version 4.0 provides a direct interface to the existing Electronic Interlocking System.
True. Direct interface with Electronic Interlocking is a version 4.0 improvement.
6.Kavach implementation relies on RFID tags laid along the track and optical fibre cable.
True. RFID tags and OFC are key components.
7.Kavach uses microprocessors, GPS and radio communication to help ensure safe train operations.
True. Kavach integrates microprocessors, GPS and radio communication.
8.Kavach provides automatic protection against Signal Passing at Danger (SPAD).
True. It protects automatically against SPAD.
9.Kavach complies with SIL-4, the highest safety integrity level.
True. Kavach meets SIL-4.
10.The previous single-day record for Kavach commissioning was on the Vadodara–Virar section.
False. The previous record of 324 RKm was on Kota–Mathura of West Central Railway.
11.Kavach can apply brakes automatically when another train is detected on the same track within a predefined distance.
True. The system alerts the loco pilot and automatically applies brakes if required.
Written by us from the release, not by UPSC; checked by a second model.
Worth revising until Prelims 2027: most news questions come within two years of the event.