Alf. Many thanks for the insightful information and questions you pose. From my experience flying B747s around the world for the past 15 years and 22 years in the USAF flying C-141s, I have often seen airports that are very marginally capable of supporting big airplanes. Quito is one of them. The runway should be made longer, the ILS glideslope issue resolved somehow so that crews can stay on a constant glideslope all the way to touchdown in the first 3,000 feet, where the traditional runway markings are indicated. Other airports include Mexico City, where a very tight VOR approach and final turn to the runway 05R is sometimes required - at night during cargo operations. Very little time to get stable on final approach, with ground speeds approaching 200 knots. El Doret, Kenya - unreliable ILS signals, a very small, marginally satisfactory turnaround area at the end of the runway, with a steep dropoff and no margin for error. Norfolk NAS, where I first flew into and out of in 1975 in C-141s, still has a totally unsatisfactorily short runway for big B747 type of airplane operations, some 30 years later. Lagos, Kinshasha, Cairo West, Kathmandu, even JFK in New York on the Canarsie approach. Don't forget Runway 4R at JFK, a Cat 11/III runway only 8400 feet long. How many big airplanes have overrun this runway in the past? Several. Midway is the most recent US example of an airliner overrun. Teterboro comes to mind also. For all of these operations, the crew is "briefed" to be aware and be cautious, etc... But what it all boils down to is the crew is told that the airport is difficult and the burden is on them. There is no room for error. In all of these cases, the airline can point to the fact that the data "shows" that the airplane is capable of performing on these runways, both for takeoff and landing. That is true. All of these operations are capable and legal. However, in my opinion, the question in aviation is not how much runway is necessary to take off and land an airplane on a particular runway . The question is how much runway is necessary to make that operation safe? The data no doubt shows that an Airbus A340-600 is capable of stopping on a wet Rwy 35 at Quito after landing at the ILS intercept point with a given autobrake setting. The margin of safety, however, is probably not that great. Everything had to work almost perfectly, including wheel spinup necessary for thrust reverser activation, etc...