Rather than issues of lift, I suspect that this will happen because of the amount of emissions generated by aircraft. If countries take climate change seriously, as they should, aviation should be hit hard. There is an awful lot of unnecessary air travel. The downside is that I'll miss my annual warm-up trips to Cuba or the Mayan Riviera and I'd better fit in one more visit to Australia to visit my brother, his kids and grandkids while I can afford it and I'm not too old!