How close can separation be during a landing clearance?

Question

How close can separation between two aircraft be during landing? during visual landing clearance?

Specifically, I refer to this Aviation Herald Report where:

When the Boeing 777-300 was about 2.1nm before touch down a BAe Avro began its takeoff run on runway 08R. The Boeing 777 was subsequently cleared to land on runway 08R, winds from 130 degrees at 7 knots.

When the Boeing 777-300 crossed the runway threshold, the Jumbolino was climbing out still short of the runway end.

^{(Source: www.avherald.com - Singapore B773 at Munich on Nov 3rd 2011, runway excursion)}

Is it typical for two aircraft to be so close during landing? i.e. Essentially both landing & departing aircraft are simultaneously overflying the same runway but at opposite ends.

How much closer would cause the landing aircraft to abort? Would one proceed with landing even if when one crossed the threshold the other craft was just rotating?

There's other things that went wrong in that incident, but I'm only asking about the close separation in the landing clearance visual clearance aspect.

PS. I've edited the question to remove a confusing misunderstanding. It was apparently not a visual clearance.

Answer 1

According to the avherald article, the airport was operating below visual minima, thus no visual approach would have been possible. Unfortuntely, the ATC communication transcript is not available, so we will will not know whether the CAT III AutoLand approach by the B773 was communicated to ATC, which would not allow the Avro to enter the runway protected area during the B773's approach or whether this was a decision by the B773 crew only.

Since the airport was operating under CAT I procedures, the B773 is likely to have been cleared for a CAT I ILS approach. The Avro will have been cleared for departure before the B773 was cleared to land, ATC has most likely used a non-withheld landing clearance.

321.5 Landing clearance need not be withheld until prescribed separation exists if there is reasonable assurance that the appropriate separation will exist when the aircraft crosses the runway threshold. However, do not clear an aircraft to land before a preceding landing aircraft has crossed the runway threshold.

The runway is considered no longer occupied if the preceding departing aircraft has reached V_r and has rotated, although still being over the runway. If ATC can be reasonably sure that this will be the case when the landing aircraft crosses the threshold, the landing clearance can be issued.

The BFU bulletin reads:

The B777 crossed the runway threshold of 08R at 12:09:09 in 40ft. Six seconds later, the BAe Avro crossed the opposite runway threshold at approx. 380ft.

^{(Source: BFU Bulletin NOV 2011 - Translation: Own Work)}

Is it typical for aircraft to be so close during approach and departure? Yes, aircraft can be close during these phases, depending on procedures in use and meteorological conditions. Aircraft can be asked to maintain visual separation to preceding traffic in VMC, however without the full transcript of the ATC communication, this will not be answerable in regards to your scenario in Munich.