An aviation expert has told Sky News disruption to flights caused by the closure of Heathrow Airport is likely to continue into the weekend. Paul Charles, head of the PC Agency, said the cost to airlines is likely to be around £30m - but that figure is likely to rise if the delays continue. Heathrow bosses say the airport will be closed all of Friday after a fire at a nearby electricity substation caused power outages. Live updates: https://news.sky.com/story/large-fire-at-electrical-substation-in-west-london-causes-power-outages-13332920 #heathrow #heathrowairportlive #heathrowairportlondon #traveladvice SUBSCRIBE to our YouTube channel for more videos: http://www.youtube.com/skynews Follow us on Twitter: https://twitter.com/skynews Like us on Facebook: https://www.facebook.com/skynews Follow us on Instagram: https://www.instagram.com/skynews Follow us on TikTok: https://www.tiktok.com/@skynews For more content go to http://news.sky.com and download our apps: Apple https://itunes.apple.com/gb/app/sky-news/id316391924?mt=8 Android https://play.google.com/store/apps/details?id=com.bskyb.skynews.android&hl=en_GB Sky News Daily podcast is available for free here: https://podfollow.com/skynewsdaily/ Sky News videos are now available in Spanish here/Los video de Sky News están disponibles en español aquí: https://www.youtube.com/channel/UCzG5BnqHO8oNlrPDW9CYJog To enquire about licensing Sky News content, you can find more information here: https://news.sky.com/info/library-sales