Originally Posted by
parabellum
Don't know about the -800 but departing Singapore for London on a warm, humid night in a -400, with a full load, you will see the end reds, rotation was within the last 1000'. Edited to add PW4056 engines.
On the runways that we are driving -400's heavy off, the centerline lights commence white/red alternating configuration at 3000' from the end of the runway. The runway edge lights change at 2000' to run. Out of say, LAX, SIN, BKK/VTBS, LHR, etc, then on a normal takeoff on 4 blowers, you would expect to be rotating about 3 seconds before reaching the coaming cutoff of the change in center line lighting configuration. 2 holer aircraft are much further back, so long as they are running on both blenders. Thats for the commencement of rotate, which takes some time and distance to transition to getting wheels to come off the ground. The FCTM gives good guidance on what should occur, and what happens with various abused conditions.
Planes can be heavy, acceptable GW error margins are dependent on regulator, with at least the Euros caring somewhat, but then we see a lot of nasty end of runway events with euro avions, not all being 'A170-Babes". Occasionally, stuff happens, but it should be for a cause, such as weight, temp, wind, or other operational oops. It is neither safe or legal to have aircraft that are exciting on all takeoffs in limit cases, without a cause. The airworthiness basis of an aircraft is that it is safe, and that it complies to the TC, which then indicates certification basis (revision level of CS/FAR 25 etc). If the plane doesn't meet either of those factors, then the definition of airworthy becomes a topic. Cruise level-normal) data is not certified by the regulator, TO and LDG data is.
Deregulation forces competition, which puts stress on efficiency. We don't lose many engines every year, and most are not within the region where it will be exciting, on limit cases. If it does, you have a bad day, or interesting photo ops. I fly an aircraft today that is permitted to be exciting, but we don't have passengers, only tactical crew who are prepared to accept the risk and see the funny side.
Characteristics of runway centreline lights
9.9.5 – Runway centreline lights are to be inset, fixed lights showing white from the threshold to a point 900m from the runway end. From 900m to 300m from the runway end, the light pattern is to be two red lights followed by two white lights. For the last 300m before the runway end, the lights are to show red.
Characteristics of high intensity runway edge lights
9.2.16 – High intensity runway edge lights are to be fixed unidirectional lights with the main beam directed towards the threshold.
9.2.17 – High intensity runway edge light beam coverage are to be toed in towards the runway as follows:
(a) 3.5° in the case of a 30-45m wide runway;
(b) 4.5° in the case of a 60m wide runway.
9.2.18 – High intensity runway edge lights are to show variable white except for those located within 600m from the runway end which are to show yellow.