Kavach: India’s Automatic Train Protection System

Kavach is India’s own Automatic Train Protection system. The word means shield. This card gives the idea and the first facts.

What problem does it solve?

A driver can miss or misread a signal, and fog hides signals. Older signalling relied on the Loco Pilot to spot signals and control speed. Kavach adds a second layer that watches the train all the time.

PIB says Kavach protects against Signal Passing at Danger, called SPAD. It also protects against excess speed and collisions.

What does ATP mean?

An ATP system checks the train’s speed against the limits set by the signals. If the train goes over the limit, ATP brakes it. Kavach does this on its own when the Loco Pilot fails to act.

Who built it?

RDSO developed Kavach with three Indian vendors, according to PIB in 2022. It is indigenous. It needs safety certification at SIL-4, which is the highest order.

Kavach is not one box. It is a set of equipment on the track, at stations and inside the engine. This card lists the five key activities.

What are the five activities?

PIB lists these as the key activities:

• Station Kavach at every station and block section.
• RFID tags along the whole track.
• Telecom towers along the section.
• Optical Fibre Cable laid along the track.
• Loco Kavach on every locomotive.

How do the parts talk to each other?

Kavach uses UHF radio and track-mounted RFID tags. The tags tell the train exactly where it is. Station units collect live data from the station interlocking system.

The Loco Pilot sees signal information on a display in the cab. It shows the movement authority, the target speed and the target distance.

Kavach does more than brake. This card lists the features and shows one working chain.

What are its features?

The 2022 PIB reply lists six salient features:

• It brakes the train automatically when the Loco Pilot fails to brake.
• It repeats the line-side signal inside the cab. This helps at high speed and in fog.
• It works on a continuous update of the Movement Authority.
• It whistles automatically at level crossing gates.
• Locos talk to each other directly to avoid collisions.
• It supports an SOS call to control trains nearby after a mishap.

Which dangers does it guard against?

PIB says Kavach guards against Signal Passing at Danger and against side, head-on and rear-end collisions. In January 2026 a head-on collision test was run on a Kavach 4.0 section. The train stopped by itself.

Kavach took years of trials before it became the national standard. This card gives the dates in order.

What happened first?

The first field trials on passenger trains began in February 2016. An Independent Safety Assessor then checked the system. In 2018-19 three firms were approved to supply Kavach Version 3.2.

When did it become national?

Kavach was adopted as the National ATP system in July 2020. By 2022 the trials covered a 250 km stretch on South Central Railway.

Did the plan hold?

In March 2022 PIB said the roll-out on New Delhi-Howrah and New Delhi-Mumbai was targeted for completion by March 2024. Version 4.0 was approved only on 16 July 2024. As the later cards show, both routes were still being covered in 2026.

The versions matter for exams. This card compares them.

What was Version 3.2?

Version 3.2 was deployed on 1,465 route km of South Central Railway. Railways gained a lot of experience from it.

What did Version 4.0 add?

RDSO approved Version 4.0 on 16 July 2024. PIB lists four main improvements:

• Better location accuracy.
• Better signal information in bigger yards.
• A station-to-station Kavach link over optical fibre.
• A direct link to the existing Electronic Interlocking system.

Version 4.0 is planned for large-scale deployment.

What is Version 5.0?

Kavach 5.0 was announced in April 2025 for suburban sections. PIB says Vande Bharat 4.0 is envisaged to carry Kavach 5.0.

What is the trap?

PIB said in February 2026 that Kavach was on more than 2,200 route km in all versions. Version 4.0 alone was over 1,300 route km then. Do not mix the two totals.

The numbers grew fast in 2026. This card gives the dated figures.

How much route has Version 4.0 covered?

• 30 January 2026: 1,306.3 route km in five zones.
• 11 March 2026: 1,452 route km, made of Delhi-Mumbai 1,099 and Delhi-Howrah 353.
• 13 July 2026: 2,490 route km, made of Delhi-Mumbai 1,344 and Delhi-Howrah 1,146.

Trackside work has been taken up on 21,937 route km.

What is installed so far?

The Lok Sabha reply of 22 July 2026 gives these figures:

• Optical fibre cable: 11,253 km.
• Telecom towers: 1,668.
• Station data centres: 958.
• Trackside equipment: 7,721 route km.
• Locomotives fitted: 6,045.

Work on another 7,435 locomotives and 1,200 EMU and MEMU sets has been taken up.

People and money decide how fast Kavach spreads. This card gives both.

How many staff are trained?

More than 94,000 staff have been trained, as per the July 2026 reply. About 57,000 of them are Loco Pilots and Assistant Loco Pilots. The courses were designed with IRISET.

In March 2025 PIB gave more than 20,000 technicians, operators and engineers. The two counts cover different groups.

How much money has gone in?

• Up to June 2026, Rs 3,874.9 crore had been used. That is about Rs 3,875 crore.
• The 2026-27 allocation is Rs 2,066.24 crore. That is about Rs 2,066 crore.
• In March 2025, Rs 1,950 crore had been used. The 2024-25 allocation was Rs 1,112.57 crore.

What does it cost per unit?

In March 2025 PIB gave about Rs 50 lakh per km for trackside and station equipment. It gave about Rs 80 lakh per loco for the onboard unit.

The year brought a record, a speed target and new sanctions. This card lists them.

What was the record day?

On 30 January 2026 Railways commissioned 472.3 route km of Kavach 4.0 in one day. It was the highest in a single day and in a month. The Vadodara-Virar section of 344 km was part of it. The Dadar-Bhuj Sayajinagri Express was the first Kavach-equipped train to run from Mumbai.

What about speed?

A Delhi-Howrah section is cleared for 130 kmph. Works under Mission Raftar aim for 160 kmph.

What was sanctioned in September 2026?

• Rs 170 crore for Kavach 4.0 on the remaining 712 route km of Moradabad Division, Northern Railway.
• Rs 233 crore for Electronic Interlocking at 21 stations of Samastipur Division.

Kavach 4.0 links directly to Electronic Interlocking, so both works support each other.

Kavach is one part of a wider safety push. This card puts it in context.

How have accidents moved?

PIB reports that consequential train accidents fell from 135 in 2014-15 to 31 in 2024-25. For 2025-26, up to November, the count was 11. PIB credits Kavach together with other tools. The release does not split the credit.

How much is spent on safety?

• 2013-14: Rs 39,200 crore.
• 2022-23: Rs 87,336 crore.
• 2023-24: Rs 1,01,662 crore.
• 2024-25: Rs 1,14,022 crore.
• 2025-26: Rs 1,17,693 crore.

Where does the National Rail Plan come in?

The National Rail Plan for India 2030 aims to create a future ready railway system by 2030. It is a separate plan. Kavach is not named as one of its parts in the pages read.

Exams test who built Kavach and what it does. This card shows one past question.

What did UPSC CSP 2025 ask?

The answer is (a), I and II only. The plan targets 2030, not 2028. Kavach is indigenous and was built by RDSO with Indian vendors. RFID tags on the track are part of Kavach.

What are the traps?

1. Origin. Kavach is indigenous. It is not a German system.
2. Totals. More than 2,200 route km is all versions. Version 4.0 alone was over 1,300 in February 2026.
3. Dates. Adopted as national ATP in July 2020. Version 4.0 approved on 16 July 2024.
4. Level. SIL-4 is the highest of four levels.
5. Plan year. The National Rail Plan looks to 2030.