{"id":1682,"date":"2025-07-02T13:25:17","date_gmt":"2025-07-02T08:25:17","guid":{"rendered":"https:\/\/news.iq\/?p=1682"},"modified":"2025-07-03T01:08:30","modified_gmt":"2025-07-02T20:08:30","slug":"fire-that-closed-heathrow-traced-to-unrepaired-transformer","status":"publish","type":"post","link":"https:\/\/news.iq\/en\/fire-that-closed-heathrow-traced-to-unrepaired-transformer\/","title":{"rendered":"Fire that closed Heathrow traced to unrepaired transformer"},"content":{"rendered":"<p>A fire at an electrical substation that forced a shutdown at London&#8217;s Heathrow Airport in March was likely caused by moisture entering electrical components, a problem first flagged in 2018, a report said Wednesday.<\/p>\n<p>Water entering a transformer and causing a short circuit &#8220;most likely&#8221; started the fire, according to the National Energy System Operator (NESO) report, adding that elevated moisture readings were detected in July 2018 but &#8220;mitigating actions appropriate to its severity were not implemented&#8221;.<\/p>\n<p>The fire broke out at the North Hyde substation in West London, around two miles (3.2 km) north of Heathrow, at 11:21 pm on March 20, resulting in a complete loss of power supply to part of the airport&#8217;s private internal electrical distribution network.<\/p>\n<p>The airport was closed for most of March 21, affecting around 270,000 journeys and raising serious questions about the reliability of one of the UK&#8217;s most critical pieces of infrastructure.<\/p>\n<p>Using forensic analysis from the National Grid Electricity Transmission and London Fire Brigade, the government-commissioned report concluded that &#8220;a catastrophic failure&#8221; on high voltage &#8220;bushing&#8221; components caused a fire to ignite on the transformer.<\/p>\n<p>&#8220;This was most likely caused by moisture entering the bushing causing a short circuit. The electricity likely then &#8216;arced&#8217; (causing sparks) which combined with air and heat to ignite the oil, resulting in a fire,&#8221; it added.<\/p>\n<p>An elevated moisture reading in one of the bushings had been detected in oil samples taken in July 2018, indicating &#8220;an imminent fault and that the bushing should be replaced&#8221;.<\/p>\n<p>However, &#8220;controls in place were not effective and failed to identify subsequently that action had not been taken in relation to the elevated moisture reading,&#8221; it said.<\/p>\n<p>&#8220;This includes an opportunity in 2022 when a decision was taken to defer basic maintenance. The issue therefore went unaddressed,&#8221; added the report.<\/p>\n<p>&#8211; &#8216;Risks were not addressed&#8217; &#8211;<\/p>\n<p>Energy Minister Ed Miliband called the report &#8220;deeply concerning&#8221;.<\/p>\n<p>&#8220;Known risks were not addressed by the National Grid Electricity Transmission, and (energy regulator) Ofgem has now opened an official enforcement investigation to consider any possible licence breaches,&#8221; he said in a statement.<\/p>\n<p>The National Grid responded in a statement that &#8220;we fully support the recommendations in the report&#8221; and that &#8220;we will also cooperate closely with Ofgem&#8217;s investigation&#8221;.<\/p>\n<p>Around 230,000 passengers use Heathrow every day &#8212; 83 million a year &#8212; making it one of the world&#8217;s busiest airports. Planes from Heathrow serve around 80 countries.<\/p>\n<p>The airport welcomed the report, which it said &#8220;sheds further light on the external power supply failure&#8221;.<\/p>\n<p>&#8220;A combination of outdated regulation, inadequate safety mechanisms, and National Grid&#8217;s failure to maintain its infrastructure led to this catastrophic power outage,&#8221; a spokesperson said.<\/p>\n<p>&#8220;We expect National Grid to be carefully considering what steps they can take to ensure this isn&#8217;t repeated.&#8221;<\/p>\n<p>jwp\/js<\/p>\n<p>\u00a9 Agence France-Presse<\/p>\n","protected":false},"excerpt":{"rendered":"<p>A fire at an electrical substation that forced a shutdown at London&#8217;s Heathrow Airport in March was likely caused by moisture entering electrical components, a problem first flagged in 2018, a report said Wednesday. Water entering a transformer and causing a short circuit &#8220;most likely&#8221; started the fire, according to the National Energy System Operator [&hellip;]<\/p>\n","protected":false},"author":3,"featured_media":1683,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_sitemap_exclude":false,"_sitemap_priority":"","_sitemap_frequency":"","jnews-multi-image_gallery":[],"jnews_single_post":{"subtitle":"","format":"standard","override":[{"template":"7","parallax":"1","fullscreen":"1","layout":"left-sidebar","sidebar":"default-sidebar","second_sidebar":"default-sidebar","sticky_sidebar":"1","share_position":"topbottom","share_float_style":"share-monocrhome","show_share_counter":"1","show_view_counter":"1","show_featured":"1","show_post_meta":"1","show_post_author":"1","show_post_author_image":"1","show_post_date":"1","post_date_format":"default","post_date_format_custom":"Y\/m\/d","show_post_category":"1","show_post_reading_time":"0","post_reading_time_wpm":"300","post_calculate_word_method":"str_word_count","show_zoom_button":"0","zoom_button_out_step":"2","zoom_button_in_step":"3","show_post_tag":"1","show_prev_next_post":"1","show_popup_post":"1","number_popup_post":"1","show_author_box":"1","show_post_related":"0","show_inline_post_related":"0"}],"image_override":[{"single_post_thumbnail_size":"crop-500","single_post_gallery_size":"crop-500"}],"trending_post_position":"meta","trending_post_label":"Trending","sponsored_post_label":"Sponsored by","disable_ad":"0"},"jnews_primary_category":[],"jnews_social_meta":[],"jnews_override_counter":{"view_counter_number":"0","share_counter_number":"0","like_counter_number":"0","dislike_counter_number":"0"},"jnews_post_split":{"post_split":[{"template":"1","tag":"h2","numbering":"asc","mode":"normal","first":"0","enable_toc":"0","toc_type":"normal"}]},"footnotes":""},"categories":[198],"tags":[497,159,209,412,498],"class_list":["post-1682","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-miscellaneous","tag-airport","tag-aviation","tag-britain","tag-fire","tag-heathrow"],"_links":{"self":[{"href":"https:\/\/news.iq\/en\/wp-json\/wp\/v2\/posts\/1682","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/news.iq\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/news.iq\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/news.iq\/en\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/news.iq\/en\/wp-json\/wp\/v2\/comments?post=1682"}],"version-history":[{"count":0,"href":"https:\/\/news.iq\/en\/wp-json\/wp\/v2\/posts\/1682\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/news.iq\/en\/wp-json\/wp\/v2\/media\/1683"}],"wp:attachment":[{"href":"https:\/\/news.iq\/en\/wp-json\/wp\/v2\/media?parent=1682"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/news.iq\/en\/wp-json\/wp\/v2\/categories?post=1682"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/news.iq\/en\/wp-json\/wp\/v2\/tags?post=1682"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}