Если хотите лететь лоукостом, то может не прокатить. Коротко - виза не нужна, если транзит в течение 24 часов и на руках билет в третью страну. http://forum.awd.ru/viewtopic.php?t=116019Можете распечатать правило визовой уступки при 24-ом транзите и возить с собой:https://www.gov.uk/check-uk-visa/y/russia/transit/yesTransiting without a visaYou might be eligible for the ‘transit without visa concession’ if:    you arrive and depart by air    have a confirmed onward flight which leaves within 24 hours    have the correct documents for your destination (eg a visa for that country)The ‘transit without visa concession’ is decided by the immigration officer at the border. You won’t be allowed to transit if they decide you need a visa, so you might want to apply for a transit visa before you travel.