In a situation like this there are two main problem,
1) The runways need de-icing every 6 hours or so. They shut one runway and operate on a single runway for a period of up to an hour. They then shut the other runway and de-ice the original one. This is usually staggered to try and minimise operational impact.
2) Aircraft must be de-iced. It takes up to 25mins to de-ice an aeroplane. BA do not have a de-icing rig per plane and therefore resources are stretched.
A plane calls ready to start it’s engines – due to the reduced ability to push planes through the system from single runway, reduced visibility, increased runway occupancy times in slippery conditions – the usual movement rate at Heathrow of about 86 planes (take off’s and landing’s) is reduced. Sometimes by up to a third.
There just isn’t any slack in the system. It’s not BA’s fault it’s not Ferrovial’s fault it’s not ATC’s fault. There are just situations where delays happen.
We have to remember that throwing yourself down a concrete strip at 200 mph to get airborne and fly for up to 12 hours has inherent risks. High energy, high speed maneuverers in icy conditions are not good. Everything must slow down. It’s just part of it.
I’m not saying things couldn’t be done better – especially communication – but let’s think about why the delays happen rather than looking for an outlet for our frustration.