Forum Topic

70% noise reduction for aircraft.

I have been an anti 3rd runway person up until now, but NASA appears to have had some success in reducing noise.https://www.huffingtonpost.co.uk/entry/nasas-found-a-way-to-make-planes-70-quieter-when-landing_uk_5b320ba3e4b0b745f1778d36?utm_hp_ref=uk-innovationhttps://www.nasa.gov/press-release/nasa-technologies-significantly-reduce-aircraft-noiseNASA have a good track record, so perhaps the 3rd runway will be ok if cars and planes can also become less polluting. Given it will take a decade or more for it to get built, the pollution from cleaner cars/planes might also improve sufficiently.Perhaps finding ways to make a 3rd runway better rather than just saying no is a better approach. Putting a T Charge zone around Heathrow could also really help with road based pollution?This news has pushed my needle from anti to undecided. Food for thought. Feedback welcome.

Christopher Gillie ● 2776d6 Comments

There is only one solution to this problem, and that is to move London’s Airport to East Anglia. This will involve moving the 75,000 approx people that work there, and provide new links for the businesses in the Thames Valley that use it. It has been done in other parts of the world, and we are very good at such engineering feats.The space that was Hounslow Heath would become a new Garden suburb, turning the terminals into shopping centres, universities and factories etc. A 4 Runway hub in East Anglia would be easier to connect via road and rail to the north and the continent. The Estuary Airport had too many problems. Fog, birds, wrecks. It would however have been great to travel onwards by boat to the Pool of London! In the meantime, Gatwick should get on with another runway, before installing 3 more at Stansted.All it needs is a few politicians with imagination and bollocks?! I know, hard to find, and probably rules out Mrs May?;(

David Farmery ● 2769d

The average airliner has a lifespan of a good 20 years, so whatever's in the air today will still be there long into the future.  The only way to reduce the pollution caused by Heathrow is simply to reduce the number of planes using it and move the London Hub to Gatwick.

Lorne Gifford ● 2772d

I think that while the noise pollution reduction is welcome (and largely down to improved aerodynamics, the air pollution has 2 major components: aircraft, and transport to an from the airport.While a Heathrow T Charge and electrification of cars will help with the second, actually making aircraft less polluting looks like it will take a lot longer. I have seen some talk about short range electric aircraft, but it all seems quite speculative.

Christopher Gillie ● 2774d

Will the new Boeing hyper sonic plane be quiet?

Nicholas Beard ● 2775d

And I've accidentally done the one thing in that post that I don't like to do; not keep it very clear that noise pollution and air pollution are very different things.Noise pollution is the amount of noise something makes (obviously), air pollution is the stuff it throws out that we breathe in and tends to make us unwell (particulates, nitrous oxides and various other toxic emissions).  When newspapers talk about 'pollution' as a single entity they're normally referring only to noise.

Lorne Gifford ● 2775d

The typical efficiency of aircraft jet engines in converting fuel to power is around 38%. ie, only 38% of the available energy in the fuel actually ends up being used to push the plane along.  The maximum efficiency you can get them to is about 42% if various improvements can be made to their materials to allow them to run hotter.Noise can be reduced, but interestingly it normally results in lower fuel to power efficiency and higher exhaust pollution (and higher fuel burn which is something engine owners aren't too keen on).So there isn't much more that can be done to jet engines to make them any less polluting and any airport owner or politician that claims otherwise doesn't have a scooby-doo about the basics of thermodynamics.Whilst 38 or 42% efficiency might sound bad, they're actually getting quite close to the theoretical limit that can be achieved by a single stage Brayton Cycle heat engine before the laws of thermodynamics kick in and stop any more efficiency improvements.  For comparison the diesel or petrol engine in your car will typically only convert 15 or 20% of the fuel you put in the tank into motive force.  The rest goes out of the exhaust pipe and radiators as heat.

Lorne Gifford ● 2775d