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Dumbledor
2nd Jan 2011, 19:27
I was wondering if scarce resources and valuable de-icing fluid could have been saved after the recent LHR and LGW snowfalls.

While visiting Norway, Lapland Russia etc over the years in the winter it seems that they leave the ramps and sometimes taxiways covered in compacted snow/ice. I remember taking pictures of a Concorde in Roveniemi, Lapland on compacted snow and the taxiways were the same. All an a/c needs is a clean airframe and runway, as long as the taxiways/ramps have been ploughed and push back is not an issue of course. I know some of these places can be so cold that the snow won't melt and refreeze but not in late autumn or early spring. I saw an aerial shot of LHR on the news after most the clearing had been done and the taxiways and ramps had been completely de-iced. The obvious trick is to have enough ploughs to move the snow as it falls before any warming and refreezing, BUT after that the ramps could be left with a thin layer of compacted snow/ice. Ground vehicles and tugs may need chains but at least the apt can get going quicker. Navigation on the ground without follow-me cars as per Moscow would be a problem, so the signs and taxiway markers would need to be kept visible, so after ploughing the taxiways the lines and stop bars would need to be de-iced.

Is it time we look at how they do it in Oslo/Stockholm and I'm not just talking about spending more money on more equipment (which BAA needs to do anyway)

D

safewing
4th Jan 2011, 21:48
Dumbledor

It very much depends on the type of snow (wet/dry) the quantity, the temperature and what you are use to.

Western Europe is not sufficiently equipped for snow. FACT.

In countries where the snow is compacted they usually stay below freezing throughout the day and the soil temperatures are very cold to quite a considerable depth so there is little risk of ice.

IN countries that receive relative small accumulations or where the daytime temperature rise to above zero, ice on the surface is possible.

This surface is extremely hazardous especially when you are in effect landing a tricycle at 150 mph.

Friction levels on compacted snow can be good. Ice not so good.

Perhaps if they had a crystal ball and could determine how much snow would fall (wait isn't that weather forecasting?!!) better decisions could be made to manage the surfaces.

FEHERTO
5th Jan 2011, 16:25
Safewing: The UK are not properly equipped, Central and Northern Europe is pretty well. For South Europe it is not feasable to spend too much money.

The London airports went down with 10cm of snow, when we talk in Frankfurt or Vienna about 40cm in a shorter period.

Dumbledor
7th Jan 2011, 13:33
FEHERTO, I agree the UK needs to be far better equipped and trained and a snow crisis happening 3 times in a year ceases to be a rare occurrence. If it now means having excess snow ploughs sitting around waiting for the next snow fall, so be it. The CAA will have to up the minimum standards for snow clearing.

SAFEWING I agree it depends on the type of snow but don't think that say Oslo or Arlanda or even Lapland are always too cold to allow for melting. In late Autumn and early spring you will still get daytime temperatures warm enough to melt snow which will refreeze at night. This is the same problem that we get here. The trick is to remove the snow as it falls and not wait for it to settle.

When it comes to clearing and de-icing ramps and taxiways in Northern Europe, these are normally just ploughed/brushed and left with patches of this snow and ice. It doesn't really create a problem as the vehicles are probably equipped with snow tyres etc, but this would probably be unacceptable in the UK. They would have been de-iced. I've taxied on sheet ice and though snow in Russia and it was not a big problem. I've slipped in sheet ice on pavements in Norway and Lapland but it seems they are just left like that. Cold dry snow would be much better of course. Do we have an over-protective safety culture in the UK when it comes to clearing snow and ice? (this is not aimed at clearing of runways at all)
D