The LHB coaches used by Indian Railways are based on a design from which country?

The correct answer is A, an Automatic Train Protection system. Kavach is an electronic safety system that acts on a moving train when its driver does not: it applies the brakes if a signal at danger is being approached without braking, holds a train back from passing a red signal, and keeps two locomotives fitted with the system from closing on each other. Option B describes services run by the Indian Railway Catering and Tourism Corporation, which is a separate arm of the Railways altogether. Option C is wrong because a gauge is the distance between the rails, and Indian Railways uses broad gauge of 1,676 millimetres on its main network; Kavach is fitted on existing track and changes nothing about the gauge. Option D is wrong because freight tracking is done through the Freight Operations Information System, a data application, and not by a safety system fitted to locomotives and stations.

The correct answer is A, the Research Designs and Standards Organisation, usually written as RDSO. It is the research, design and standards wing of Indian Railways, has its headquarters at Lucknow, and developed Kavach in partnership with Indian manufacturers, first under the name Train Collision Avoidance System. Option B, the Centre for Railway Information Systems, builds and runs the computer systems of the Railways, such as passenger reservation and freight information, and does not design signalling hardware. Option C, the Indian Railway Catering and Tourism Corporation, handles catering, online ticketing and tourist trains. Option D, the Dedicated Freight Corridor Corporation of India, was set up to build and manage the Eastern and Western freight corridors. All four are genuine railway bodies, which is why the question is a test of what each one actually does.

The correct answer is D, SIL-4. Safety Integrity Level is a scale of four grades used for safety related electronic systems, and level four is the most demanding, meaning the probability of a dangerous undetected failure is designed to be the lowest of all. Signalling and train protection systems on main line railways are built to this level because a single failure can cost many lives, and Kavach was certified accordingly before being adopted as the national Automatic Train Protection standard. Options A, B and C, the lower levels, are used for systems whose failure carries a smaller consequence, such as some industrial process controls and auxiliary equipment; accepting a lower level for train protection would defeat its purpose. A candidate who remembers only the phrase highest level will still get this question right, because SIL-4 is the highest of the four.

The correct answer is C, a derailment caused by a fractured rail. Kavach works on the movement of trains: it reads the position and speed of a locomotive from trackside tags, compares that with the signal and the permitted speed, and brakes the train when the driver does not. It therefore covers options A, B and D, which are all failures of driving or of spacing between trains. It has no way of knowing that a rail has cracked, that a landslide has covered the track or that a coach axle is defective, because it does not inspect the track structure or the rolling stock. Those hazards are addressed by separate measures such as ultrasonic flaw detection of rails, track recording cars and coach maintenance schedules. Examiners set this distinction precisely because Kavach is often described loosely as an anti-accident system.

The correct answer is B, the Integral Coach Factory at Chennai, which designed the train set under the project name Train 18 and rolled out the first rake. Option A, the Rail Coach Factory at Kapurthala in Punjab, builds LHB coaches and other passenger stock but did not design this train set. Option C, Chittaranjan Locomotive Works in West Bengal, builds electric locomotives, and a Vande Bharat rake does not use a locomotive at all, since its propulsion equipment is distributed under the coaches. Option D, the Modern Coach Factory at Raebareli in Uttar Pradesh, is the newest of the coach factories and also builds LHB stock. All four are production units of Indian Railways, so the question is really asking which unit does which job, and coach design of this kind belongs to Chennai.