{"id":36480,"date":"2022-02-20T20:40:23","date_gmt":"2022-02-21T01:40:23","guid":{"rendered":"https:\/\/philip.greenspun.com\/blog\/?p=36480"},"modified":"2022-02-20T20:40:23","modified_gmt":"2022-02-21T01:40:23","slug":"helicopter-autorotation-off-miami-beach","status":"publish","type":"post","link":"https:\/\/philip.greenspun.com\/blog\/2022\/02\/20\/helicopter-autorotation-off-miami-beach\/","title":{"rendered":"Helicopter autorotation off Miami Beach"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">Friends have been asking me to explain the recent <a href=\"https:\/\/philip.greenspun.com\/flying\/robinson-r44\">Robinson R44<\/a> autorotation off Miami Beach.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The incident, caught on surveillance camera:<\/p>\n\n\n\n<figure class=\"wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio\"><div class=\"wp-block-embed__wrapper\">\n<div class=\"jetpack-video-wrapper\"><span class=\"embed-youtube\" style=\"text-align:center; display: block;\"><iframe loading=\"lazy\" class=\"youtube-player\" width=\"1000\" height=\"563\" src=\"https:\/\/www.youtube.com\/embed\/ATFDBw994ik?version=3&#038;rel=1&#038;showsearch=0&#038;showinfo=1&#038;iv_load_policy=1&#038;fs=1&#038;hl=en-US&#038;autohide=2&#038;wmode=transparent\" allowfullscreen=\"true\" style=\"border:0;\" sandbox=\"allow-scripts allow-same-origin allow-popups allow-presentation allow-popups-to-escape-sandbox\"><\/iframe><\/span><\/div>\n<\/div><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">If it isn&#8217;t an emergency and your machine happens to be equipped with fixed or pop-out floats and you&#8217;re practicing, it looks like the following video (throttle is rolled to idle to simulate engine failure and, due to a <a href=\"https:\/\/en.wikipedia.org\/wiki\/Sprag_clutch\">sprag clutch<\/a>, the engine isn&#8217;t helping to maintain rotor speed).<\/p>\n\n\n\n<figure class=\"wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio\"><div class=\"wp-block-embed__wrapper\">\n<div class=\"jetpack-video-wrapper\"><span class=\"embed-youtube\" style=\"text-align:center; display: block;\"><iframe loading=\"lazy\" class=\"youtube-player\" width=\"1000\" height=\"563\" src=\"https:\/\/www.youtube.com\/embed\/_anQ8cFeFLA?version=3&#038;rel=1&#038;showsearch=0&#038;showinfo=1&#038;iv_load_policy=1&#038;fs=1&#038;hl=en-US&#038;autohide=2&#038;wmode=transparent\" allowfullscreen=\"true\" style=\"border:0;\" sandbox=\"allow-scripts allow-same-origin allow-popups allow-presentation allow-popups-to-escape-sandbox\"><\/iframe><\/span><\/div>\n<\/div><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Here&#8217;s one to a hard surface (cheating a little with a slide-reducing headwind that you can hear in the microphone):<\/p>\n\n\n\n<figure class=\"wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio\"><div class=\"wp-block-embed__wrapper\">\n<div class=\"jetpack-video-wrapper\"><span class=\"embed-youtube\" style=\"text-align:center; display: block;\"><iframe loading=\"lazy\" class=\"youtube-player\" width=\"1000\" height=\"563\" src=\"https:\/\/www.youtube.com\/embed\/EklDfZw-NrU?version=3&#038;rel=1&#038;showsearch=0&#038;showinfo=1&#038;iv_load_policy=1&#038;fs=1&#038;hl=en-US&#038;autohide=2&#038;wmode=transparent\" allowfullscreen=\"true\" style=\"border:0;\" sandbox=\"allow-scripts allow-same-origin allow-popups allow-presentation allow-popups-to-escape-sandbox\"><\/iframe><\/span><\/div>\n<\/div><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Let&#8217;s assume that there was an engine failure in the Miami crash, which could be due to a mechanical problem, to running out of fuel, to someone pulling the mixture control inadvertently or turning off the magnetos (I always hate to see keychains on aircraft keys or, for that matter, ignition keys to begin with (jets don&#8217;t have them so you can&#8217;t turn off a jet with your knee)), etc. In that case, since we see that the rotor blades are spinning, the Miami pilot reacted correctly by lowering collective pitch and, probably, pulling back a little on the cyclic. This preserves rotor speed and enables the blades to windmill as the helicopter descends. The potential energy from being up in the air turns into a source of power to keep the blades turning, but that power can&#8217;t be used if the blades are at a steep angle of attack compared to the new relative wind (coming up from the ground).<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The airspeed also looks pretty good. It is supposed to be 70 knots in an R44 (<a href=\"https:\/\/robinsonheli.com\/wp-content\/uploads\/2022\/01\/r44_poh_3.pdf\">POH<\/a>), but 60 knots is also sufficient for a reasonable flare and landing. What seems to have been missing in the Miami crash is the cyclic flare at the bottom. This maneuver, not that different from flaring a fixed-wing airplane on landing, turns the kinetic energy of the forward airspeed into a climb that cancels out the descent from the glide so that the net vertical speed is close to 0.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">(At the end of the flare, if you want to get everything perfect and not damage the tail, you stick forward to level the skids and finally pull the collective to use the energy of blade rotation to cushion the fall from 5&#8242; to the ground.)<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Why wouldn&#8217;t the pilot flare? One thing that we tell people in training is to begin their flare at &#8220;treetop height&#8221;. This is tough to put into practice when there aren&#8217;t any good vertical references. Even experienced seaplane pilots have a tough time judging height above the water when the water is smooth (&#8220;glassy&#8221;). One can see from the top video, when witnesses are being interviewed, that there wasn&#8217;t a lot of wave action. Aside from the difficulty of judging height above smooth water there is, of course, the difference between training and the real world of surprise and shock that things aren&#8217;t going as planned.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Fortunately, nobody was killed in the Miami crash. Counterintuitively, the injuries might have been less severe if the helicopter had contacted pavement. That&#8217;s because the skids are designed to absorb much of the downward energy of a crash, but they can&#8217;t do this job when the machine smacks down in water. In order to meet FAA and EASA certification standards, the seats themselves also have to absorb downward energy by crushing and that, presumably, is what saved the occupants from being killed by the impact that we observe on the video.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">It will be interesting to see what the NTSB can learn&#8230;<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Related:<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li><a href=\"https:\/\/philip.greenspun.com\/flying\/teaching-autorotations\">&#8220;Teaching Autorotations&#8221;<\/a> (some tips for CFIs)<\/li><li><a href=\"https:\/\/helitrak.com\/collective-pull-down\">HeliTrak Collective Pull Down<\/a> (reacts immediately even if the pilot doesn&#8217;t)<\/li><li><a href=\"https:\/\/philip.greenspun.com\/flying\/cirrus-sr20\">Cirrus SR20<\/a> (you don&#8217;t have to be a hero because you can pull the parachute)<\/li><\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Friends have been asking me to explain the recent Robinson R44 autorotation off Miami Beach. The incident, caught on surveillance camera: If it isn&#8217;t an emergency and your [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_post_was_ever_published":false},"categories":[11],"tags":[],"class_list":["post-36480","post","type-post","status-publish","format-standard","hentry","category-flying"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.3 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Helicopter autorotation off Miami Beach - Philip Greenspun\u2019s Weblog<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/philip.greenspun.com\/blog\/2022\/02\/20\/helicopter-autorotation-off-miami-beach\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Helicopter autorotation off Miami Beach - Philip Greenspun\u2019s Weblog\" \/>\n<meta property=\"og:description\" content=\"Friends have been asking me to explain the recent Robinson R44 autorotation off Miami Beach. The incident, caught on surveillance camera: If it isn&#8217;t an emergency and your [&hellip;]\" \/>\n<meta property=\"og:url\" content=\"https:\/\/philip.greenspun.com\/blog\/2022\/02\/20\/helicopter-autorotation-off-miami-beach\/\" \/>\n<meta property=\"og:site_name\" content=\"Philip Greenspun\u2019s Weblog\" \/>\n<meta property=\"article:published_time\" content=\"2022-02-21T01:40:23+00:00\" \/>\n<meta name=\"author\" content=\"philg\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"philg\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"3 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/philip.greenspun.com\\\/blog\\\/2022\\\/02\\\/20\\\/helicopter-autorotation-off-miami-beach\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/philip.greenspun.com\\\/blog\\\/2022\\\/02\\\/20\\\/helicopter-autorotation-off-miami-beach\\\/\"},\"author\":{\"name\":\"philg\",\"@id\":\"https:\\\/\\\/philip.greenspun.com\\\/blog\\\/#\\\/schema\\\/person\\\/448e4e6a0ae9105741a06dcf62cee50e\"},\"headline\":\"Helicopter autorotation off Miami Beach\",\"datePublished\":\"2022-02-21T01:40:23+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/philip.greenspun.com\\\/blog\\\/2022\\\/02\\\/20\\\/helicopter-autorotation-off-miami-beach\\\/\"},\"wordCount\":641,\"commentCount\":7,\"publisher\":{\"@id\":\"https:\\\/\\\/philip.greenspun.com\\\/blog\\\/#\\\/schema\\\/person\\\/448e4e6a0ae9105741a06dcf62cee50e\"},\"articleSection\":[\"Flying\"],\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\\\/\\\/philip.greenspun.com\\\/blog\\\/2022\\\/02\\\/20\\\/helicopter-autorotation-off-miami-beach\\\/#respond\"]}]},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/philip.greenspun.com\\\/blog\\\/2022\\\/02\\\/20\\\/helicopter-autorotation-off-miami-beach\\\/\",\"url\":\"https:\\\/\\\/philip.greenspun.com\\\/blog\\\/2022\\\/02\\\/20\\\/helicopter-autorotation-off-miami-beach\\\/\",\"name\":\"Helicopter autorotation off Miami Beach - Philip Greenspun\u2019s Weblog\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/philip.greenspun.com\\\/blog\\\/#website\"},\"datePublished\":\"2022-02-21T01:40:23+00:00\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/philip.greenspun.com\\\/blog\\\/2022\\\/02\\\/20\\\/helicopter-autorotation-off-miami-beach\\\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/philip.greenspun.com\\\/blog\\\/2022\\\/02\\\/20\\\/helicopter-autorotation-off-miami-beach\\\/\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/philip.greenspun.com\\\/blog\\\/2022\\\/02\\\/20\\\/helicopter-autorotation-off-miami-beach\\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/philip.greenspun.com\\\/blog\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Helicopter autorotation off Miami Beach\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/philip.greenspun.com\\\/blog\\\/#website\",\"url\":\"https:\\\/\\\/philip.greenspun.com\\\/blog\\\/\",\"name\":\"Philip Greenspun\u2019s Weblog\",\"description\":\"A posting every day; an interesting idea every three months...\",\"publisher\":{\"@id\":\"https:\\\/\\\/philip.greenspun.com\\\/blog\\\/#\\\/schema\\\/person\\\/448e4e6a0ae9105741a06dcf62cee50e\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/philip.greenspun.com\\\/blog\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"},{\"@type\":[\"Person\",\"Organization\"],\"@id\":\"https:\\\/\\\/philip.greenspun.com\\\/blog\\\/#\\\/schema\\\/person\\\/448e4e6a0ae9105741a06dcf62cee50e\",\"name\":\"philg\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/philip.greenspun.com\\\/blog\\\/wp-content\\\/uploads\\\/2025\\\/11\\\/20210525-philip-greenspun-sea-turtle-release-scaled.jpg\",\"url\":\"https:\\\/\\\/philip.greenspun.com\\\/blog\\\/wp-content\\\/uploads\\\/2025\\\/11\\\/20210525-philip-greenspun-sea-turtle-release-scaled.jpg\",\"contentUrl\":\"https:\\\/\\\/philip.greenspun.com\\\/blog\\\/wp-content\\\/uploads\\\/2025\\\/11\\\/20210525-philip-greenspun-sea-turtle-release-scaled.jpg\",\"width\":2047,\"height\":2560,\"caption\":\"philg\"},\"logo\":{\"@id\":\"https:\\\/\\\/philip.greenspun.com\\\/blog\\\/wp-content\\\/uploads\\\/2025\\\/11\\\/20210525-philip-greenspun-sea-turtle-release-scaled.jpg\"},\"url\":\"https:\\\/\\\/philip.greenspun.com\\\/blog\\\/author\\\/philg\\\/\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Helicopter autorotation off Miami Beach - Philip Greenspun\u2019s Weblog","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/philip.greenspun.com\/blog\/2022\/02\/20\/helicopter-autorotation-off-miami-beach\/","og_locale":"en_US","og_type":"article","og_title":"Helicopter autorotation off Miami Beach - Philip Greenspun\u2019s Weblog","og_description":"Friends have been asking me to explain the recent Robinson R44 autorotation off Miami Beach. The incident, caught on surveillance camera: If it isn&#8217;t an emergency and your [&hellip;]","og_url":"https:\/\/philip.greenspun.com\/blog\/2022\/02\/20\/helicopter-autorotation-off-miami-beach\/","og_site_name":"Philip Greenspun\u2019s Weblog","article_published_time":"2022-02-21T01:40:23+00:00","author":"philg","twitter_card":"summary_large_image","twitter_misc":{"Written by":"philg","Est. reading time":"3 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/philip.greenspun.com\/blog\/2022\/02\/20\/helicopter-autorotation-off-miami-beach\/#article","isPartOf":{"@id":"https:\/\/philip.greenspun.com\/blog\/2022\/02\/20\/helicopter-autorotation-off-miami-beach\/"},"author":{"name":"philg","@id":"https:\/\/philip.greenspun.com\/blog\/#\/schema\/person\/448e4e6a0ae9105741a06dcf62cee50e"},"headline":"Helicopter autorotation off Miami Beach","datePublished":"2022-02-21T01:40:23+00:00","mainEntityOfPage":{"@id":"https:\/\/philip.greenspun.com\/blog\/2022\/02\/20\/helicopter-autorotation-off-miami-beach\/"},"wordCount":641,"commentCount":7,"publisher":{"@id":"https:\/\/philip.greenspun.com\/blog\/#\/schema\/person\/448e4e6a0ae9105741a06dcf62cee50e"},"articleSection":["Flying"],"inLanguage":"en-US","potentialAction":[{"@type":"CommentAction","name":"Comment","target":["https:\/\/philip.greenspun.com\/blog\/2022\/02\/20\/helicopter-autorotation-off-miami-beach\/#respond"]}]},{"@type":"WebPage","@id":"https:\/\/philip.greenspun.com\/blog\/2022\/02\/20\/helicopter-autorotation-off-miami-beach\/","url":"https:\/\/philip.greenspun.com\/blog\/2022\/02\/20\/helicopter-autorotation-off-miami-beach\/","name":"Helicopter autorotation off Miami Beach - Philip Greenspun\u2019s Weblog","isPartOf":{"@id":"https:\/\/philip.greenspun.com\/blog\/#website"},"datePublished":"2022-02-21T01:40:23+00:00","breadcrumb":{"@id":"https:\/\/philip.greenspun.com\/blog\/2022\/02\/20\/helicopter-autorotation-off-miami-beach\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/philip.greenspun.com\/blog\/2022\/02\/20\/helicopter-autorotation-off-miami-beach\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/philip.greenspun.com\/blog\/2022\/02\/20\/helicopter-autorotation-off-miami-beach\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/philip.greenspun.com\/blog\/"},{"@type":"ListItem","position":2,"name":"Helicopter autorotation off Miami Beach"}]},{"@type":"WebSite","@id":"https:\/\/philip.greenspun.com\/blog\/#website","url":"https:\/\/philip.greenspun.com\/blog\/","name":"Philip Greenspun\u2019s Weblog","description":"A posting every day; an interesting idea every three months...","publisher":{"@id":"https:\/\/philip.greenspun.com\/blog\/#\/schema\/person\/448e4e6a0ae9105741a06dcf62cee50e"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/philip.greenspun.com\/blog\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"},{"@type":["Person","Organization"],"@id":"https:\/\/philip.greenspun.com\/blog\/#\/schema\/person\/448e4e6a0ae9105741a06dcf62cee50e","name":"philg","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/philip.greenspun.com\/blog\/wp-content\/uploads\/2025\/11\/20210525-philip-greenspun-sea-turtle-release-scaled.jpg","url":"https:\/\/philip.greenspun.com\/blog\/wp-content\/uploads\/2025\/11\/20210525-philip-greenspun-sea-turtle-release-scaled.jpg","contentUrl":"https:\/\/philip.greenspun.com\/blog\/wp-content\/uploads\/2025\/11\/20210525-philip-greenspun-sea-turtle-release-scaled.jpg","width":2047,"height":2560,"caption":"philg"},"logo":{"@id":"https:\/\/philip.greenspun.com\/blog\/wp-content\/uploads\/2025\/11\/20210525-philip-greenspun-sea-turtle-release-scaled.jpg"},"url":"https:\/\/philip.greenspun.com\/blog\/author\/philg\/"}]}},"jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/paokyZ-9uo","jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/philip.greenspun.com\/blog\/wp-json\/wp\/v2\/posts\/36480","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/philip.greenspun.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/philip.greenspun.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/philip.greenspun.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/philip.greenspun.com\/blog\/wp-json\/wp\/v2\/comments?post=36480"}],"version-history":[{"count":4,"href":"https:\/\/philip.greenspun.com\/blog\/wp-json\/wp\/v2\/posts\/36480\/revisions"}],"predecessor-version":[{"id":36484,"href":"https:\/\/philip.greenspun.com\/blog\/wp-json\/wp\/v2\/posts\/36480\/revisions\/36484"}],"wp:attachment":[{"href":"https:\/\/philip.greenspun.com\/blog\/wp-json\/wp\/v2\/media?parent=36480"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/philip.greenspun.com\/blog\/wp-json\/wp\/v2\/categories?post=36480"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/philip.greenspun.com\/blog\/wp-json\/wp\/v2\/tags?post=36480"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}