| Topic: | Re:Re:Re:Re:Re:3rd runway noise in Chiswick | |
| Posted by: | Tom Pike | |
| Date/Time: | 03/02/08 12:49:00 |
| Richard, The latest contours for 2006 are available on the DfT site. The shapes look very similar but the areas have dropped by 7% from 2002 mainly because Concorde was no longer with us. I quite agree 2006 would be a better baseline (2005 would be even a little quieter), but I wouldn’t exaggerate the advantage in holding future noise to 2006 rather than 2002 values. At 2200 m the third runway is long enough for A320’s and A321’s that can’t take off in 2000 m. That’s why it was lengthened. Despite what the consultation document states, I will never get on a 767, 777 or A330 taking off from the third runway – I’d likely end up on the M25 as all these planes need more than 2200 m to take off! It’s possible that the heaviest aircraft, including 747’s, could land on the third runway in an emergency, but the modelling in the consultation assumed these planes would use the existing runways even if ending up at the new terminal (see the figure on p 26 of the Runway 3 Study). Given that over two thirds of the expected traffic in 2020 will be in the quietest planes below 220 seats, I’d be very surprised if we see many planes with a QC noise rating above 0.25 landing on the third runway. The noise estimates of the new flightpath over the High Road being 4 dB quieter than the existing flightpath over Grove Park are consistent and credible. |