Although this is obviously not real-world, VATSIM does try to mimic it as closely as possible.
London Luton's VMATs has this to say:
3.2.6 Land after procedures
Normally, only one aircraft is permitted to land or take-off on the runway in use at any one time. However, when the traffic sequence is two successive landing aircraft, the second one may be allowed to land before the first one has cleared the runway in use, providing that:
- It is during daylight hours
It is during daylight hours
- The preceding aircraft does not intend to backtrack in order to vacate
The preceding aircraft does not intend to backtrack in order to vacate
- There is no evidence that braking action may be adversely affected
There is no evidence that braking action may be adversely affected
- The second aircraft will be able to see the first aircraft clearly and continuously until it is clear of the runway
The second aircraft will be able to see the first aircraft clearly and continuously until it is clear of the runway
- The second aircraft has been warned
The second aircraft has been warned
In place of the standard "cleared to land", the instruction "Land after (first aircraft type)". The responsibility for ensuring separation then lies with the pilot of the second aircraft