| Topic: | Re:3rd runway noise in Chiswick | |
| Posted by: | Tom Pike | |
| Date/Time: | 02/02/08 09:25:00 |
| The plane mix proposed for the third runway when it first opens is dominated by A320 series (see table 2.3 in the noise estimate consultation document). I'm sure you're right that the runway was lengthened so as to take these planes. But these are some of the quietest aircraft currently flying, so as Richard suggests it would have been the higher throttle during banking to join the flightpath that produced the noise levels you suffered. It is not representative of noise on a straight three-degree continuous descent to the third runway. Also, the planes will be coming in to the third runway on average about every 3 minutes in mixed mode, rather than the current 100 seconds. CAA have not randomly plucked dBA Leq to correlate noise with nuisance. These figures, whether dubbed "wretched" or “bogus,” are still the best measure in the extensive research into noise disturbance at relatively high levels. And the modelled noise contours at Heathrow have been tested against past actual flight noise. There might be better measures of nuisance at the low noise levels expected over Chiswick – just seeing the planes go overhead will be disturbing to some. But don't rely on HACAN analysis here - what they submitted to the Terminal 5 inquiry was a joke, and I hope 2M do a better job this time round. It's well worth reading the online papers by Professor Brooker from Cranfield - he is very critical of some aspects the noise of Heathrow expansion but he doesn't throw out the science with the bathwater. |