24 questions on this topic, recalled by candidates after DGCA sittings between 2021 and 2026. Together they were asked 45 times; the most repeated come first. Pick a year to see only what was asked that year.
B. 136,000 kg or more
HEAVY is 136,000 kg or more; MEDIUM is between 7000 kg and 136,000 kg; LIGHT is 7000 kg or less.
B. 1000 ft
RVSM applies 300 m (1000 ft) between FL290 and FL410 inclusive, for RVSM-approved aircraft. Outside RVSM, 2000 ft applies at and above FL290.
A. 2 minutes
The correct answer is: 2 minutes.
A. Lift off before its lift-off point and climb above its flight path
Vortices start where the heavy lifts off and then sink. Get airborne before that point and stay above its climb path, and you stay out of them.
B. FL400
Tracks 180-359 use even levels (FL300, 320 ... 400); tracks 000-179 use odd levels (FL290, 310 ... 410). FL405 is not an IFR cruising level.
B. 5 NM
5 NM. HEAVY behind HEAVY is 4 NM, LIGHT behind HEAVY 6 NM, and LIGHT behind MEDIUM 5 NM.
B. 610 m wide
At least 610 m (2000 ft) wide, equidistant between the extended runway centre lines, and shown on the controller's display.
B. Not more than 30 degrees
Not more than 30 degrees, with at least 1 NM of straight and level flight before the intercept.
B. More than 7000 kg but less than 136,000 kg
MEDIUM: above 7000 kg and below 136,000 kg. At 136,000 kg exactly you are HEAVY.
C. 2 minutes
Two minutes for a LIGHT or MEDIUM taking off behind a HEAVY from the same runway. It rises to 3 minutes if the follower departs from an intermediate part of the runway.
C. 2 minutes
Two minutes - the same figure as LIGHT or MEDIUM behind HEAVY. From an intermediate part of the runway it becomes 3 minutes.
B. 1000 ft
Below FL290: 1000 ft. At or above FL290: 2000 ft - reduced to 1000 ft only for RVSM aircraft in RVSM airspace.
C. 15 minutes
Fifteen minutes. It drops to 10 minutes if navigation aids allow frequent fixing, and to 5 minutes if the leader is 20 kt or more faster (under set conditions).
B. 10 minutes
Ten minutes with frequent position and speed checks, instead of the basic 15.
C. 5 minutes
Five minutes when the leader keeps a true airspeed 20 kt or more faster, in the listed cases. With 40 kt or more it can be 3 minutes.
A. 1 minute
One minute, because lateral separation starts immediately after take-off. On the same track the figures are 5 minutes, or 2 minutes if the leader is 40 kt faster.
A. 2 minutes
Arrivals: MEDIUM behind HEAVY - 2 minutes; LIGHT behind HEAVY or MEDIUM - 3 minutes.
B. 5 NM
5 NM (9.3 km). Where the radar allows, it may be reduced to 3 NM, and to 2.5 NM on the same final approach track within 10 NM of the runway end.
A. LIGHT
LIGHT is 7000 kg or less, so 6700 kg is LIGHT. MEDIUM is above 7000 kg and below 136,000 kg.
C. 300 ft
More than 90 m (300 ft) in the expected direction from the previous level. The same 300 ft test applies to "passed a level".
A. Staying above its approach path and touching down beyond its touchdown point
Vortices sink behind the aircraft that makes them and stop at its touchdown point. Stay above its path and land beyond where it touched down, and you stay out of them.
A. 20 NM
With both aircraft using on-track DME and position reports frequently checked, 37 km (20 NM) separates two aircraft on the same track at the same level. It reduces to 10 NM only when the leading aircraft is faster by the prescribed margin.
A. 3 minutes
The correct answer is: 3 minutes.
A. 15 minutes
The basic figure for a climb or descent through the level of another aircraft on the same track is 15 minutes; it reduces to 10 or 5 minutes only under specific conditions.
These are candidates' recollections, not official DGCA papers: wording can differ from the paper as set. Every answer was checked against the DGCA CARs, AIP India, ICAO documents or worked calculation (independent check completed 17 Oct 2026). Spotted a mistake? Tell us and we will check it against the source.