{"id":1884,"date":"2025-08-14T10:33:18","date_gmt":"2025-08-14T08:33:18","guid":{"rendered":"https:\/\/acriv.org\/WP\/?page_id=1884"},"modified":"2025-08-14T10:33:18","modified_gmt":"2025-08-14T08:33:18","slug":"%e2%9a%99%ef%b8%8faltimetre","status":"publish","type":"page","link":"https:\/\/acriv.org\/WP\/%e2%9a%99%ef%b8%8faltimetre\/","title":{"rendered":"\u2699\ufe0fALTIMETRE"},"content":{"rendered":"<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"223\" height=\"226\" src=\"https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/image-50.png\" alt=\"\" class=\"wp-image-1885\" style=\"width:183px;height:auto\" srcset=\"https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/image-50.png 223w, https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/image-50-104x105.png 104w\" sizes=\"auto, (max-width: 223px) 100vw, 223px\" \/><\/figure>\n<\/div>\n\n\n<p>Un <strong>altim\u00e8tre<\/strong> en aviation est l\u2019instrument qui indique la <strong>hauteur<\/strong> d\u2019un a\u00e9ronef par rapport \u00e0 une r\u00e9f\u00e9rence de pression atmosph\u00e9rique.<br>C\u2019est fondamental pour \u00e9viter les collisions avec le relief ou d\u2019autres appareils, et pour respecter les niveaux de vol r\u00e9glementaires.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">1. <strong>Principe de fonctionnement<\/strong><\/h2>\n\n\n\n<p>L\u2019altim\u00e8tre est un <strong>barom\u00e8tre an\u00e9ro\u00efde<\/strong> adapt\u00e9 \u00e0 l\u2019aviation :<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Capteur de pression statique<\/strong>\n<ul class=\"wp-block-list\">\n<li>L\u2019instrument est reli\u00e9 \u00e0 une <strong>prise statique<\/strong> qui mesure la pression de l\u2019air ext\u00e9rieur (non perturb\u00e9e par le d\u00e9placement de l\u2019avion).<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Capsules an\u00e9ro\u00efdes<\/strong>\n<ul class=\"wp-block-list\">\n<li>\u00c0 l\u2019int\u00e9rieur, une ou plusieurs capsules m\u00e9talliques herm\u00e9tiques, partiellement vid\u00e9es d\u2019air, se dilatent ou se contractent selon la pression ext\u00e9rieure.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>M\u00e9canisme de transmission<\/strong>\n<ul class=\"wp-block-list\">\n<li>Les mouvements des capsules sont transmis \u00e0 des aiguilles par un syst\u00e8me de leviers et d\u2019engrenages.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Graduation en altitude<\/strong>\n<ul class=\"wp-block-list\">\n<li>La pression mesur\u00e9e est traduite en altitude en utilisant le <strong>mod\u00e8le standard de l\u2019atmosph\u00e8re<\/strong> (ISA), o\u00f9 la pression diminue d\u2019environ 1 hPa tous les 27 pieds (\u2248 8 m) pr\u00e8s du niveau de la mer.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>R\u00e9glage de la pression de r\u00e9f\u00e9rence<\/strong>\n<ul class=\"wp-block-list\">\n<li>Via la petite fen\u00eatre (<em>Kollsman window<\/em>), on r\u00e8gle la pression de r\u00e9f\u00e9rence (QNH, QFE ou 1013 hPa).<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"491\" src=\"https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/image-51-1024x491.png\" alt=\"\" class=\"wp-image-1886\" style=\"width:435px;height:auto\" srcset=\"https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/image-51-1024x491.png 1024w, https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/image-51-300x144.png 300w, https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/image-51-768x368.png 768w, https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/image-51-1536x736.png 1536w, https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/image-51-2048x982.png 2048w, https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/image-51-800x383.png 800w, https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/image-51-626x300.png 626w, https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/image-51-310x149.png 310w, https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/image-51-150x72.png 150w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n<\/div>\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">2. <strong>R\u00e9glages et r\u00e9f\u00e9rences<\/strong><\/h2>\n\n\n\n<p>En aviation, on utilise trois grands r\u00e9glages de l\u2019altim\u00e8tre :<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table><thead><tr><th>R\u00e9glage<\/th><th>Valeur entr\u00e9e<\/th><th>Indication donn\u00e9e<\/th><\/tr><\/thead><tbody><tr><td><strong>QNH<\/strong><\/td><td>Pression au niveau de la mer (corrig\u00e9e m\u00e9t\u00e9o)<\/td><td><strong>Altitude<\/strong> par rapport au niveau moyen de la mer (AMSL)<\/td><\/tr><tr><td><strong>QFE<\/strong><\/td><td>Pression sur l\u2019a\u00e9rodrome<\/td><td><strong>Hauteur<\/strong> par rapport \u00e0 ce terrain (indique 0 m\/ft au sol)<\/td><\/tr><tr><td><strong>1013 hPa<\/strong><\/td><td>Pression standard<\/td><td><strong>Niveau de vol<\/strong> (Flight Level, FL) bas\u00e9 sur atmosph\u00e8re standard<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">3. <strong>Notions cl\u00e9s<\/strong><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Altitude<\/strong> : Distance verticale entre l\u2019avion et le niveau moyen de la mer (AMSL), mesur\u00e9e avec QNH.<\/li>\n\n\n\n<li><strong>Hauteur<\/strong> : Distance verticale entre l\u2019avion et une surface sp\u00e9cifique (souvent le sol ou le seuil de piste), mesur\u00e9e avec QFE.<\/li>\n\n\n\n<li><strong>Niveau de vol (FL)<\/strong> : Altitude exprim\u00e9e en centaines de pieds, mesur\u00e9e par rapport \u00e0 1013 hPa.<br>Exemple : FL080 = 8 000 ft dans atmosph\u00e8re standard.<\/li>\n<\/ul>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"768\" src=\"https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/image-52-1024x768.png\" alt=\"\" class=\"wp-image-1887\" style=\"width:359px;height:auto\" srcset=\"https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/image-52-1024x768.png 1024w, https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/image-52-300x225.png 300w, https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/image-52-768x576.png 768w, https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/image-52-800x600.png 800w, https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/image-52-400x300.png 400w, https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/image-52-310x233.png 310w, https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/image-52-140x105.png 140w, https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/08\/image-52.png 1200w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n<\/div>\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">4. <strong>R\u00e9sum\u00e9 visuel<\/strong><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>QFE \u2192 Hauteur<\/strong> (par rapport au terrain)<\/li>\n\n\n\n<li><strong>QNH \u2192 Altitude<\/strong> (par rapport \u00e0 la mer)<\/li>\n\n\n\n<li><strong>1013 hPa \u2192 Niveau de vol<\/strong> (r\u00e9f\u00e9rence standard pour s\u00e9paration verticale)<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Un altim\u00e8tre en aviation est l\u2019instrument qui indique la hauteur d\u2019un a\u00e9ronef par rapport \u00e0 une r\u00e9f\u00e9rence de pression atmosph\u00e9rique.C\u2019est fondamental pour \u00e9viter les collisions avec le relief ou d\u2019autres appareils, et pour respecter les niveaux de vol r\u00e9glementaires. 1. Principe de fonctionnement L\u2019altim\u00e8tre est un barom\u00e8tre an\u00e9ro\u00efde adapt\u00e9 \u00e0 l\u2019aviation : 2. R\u00e9glages et r\u00e9f\u00e9rences En aviation, on utilise<\/p>\n<p><a class=\"more-link\" href=\"https:\/\/acriv.org\/WP\/%e2%9a%99%ef%b8%8faltimetre\/\">Read More<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-1884","page","type-page","status-publish","hentry"],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/acriv.org\/WP\/wp-json\/wp\/v2\/pages\/1884","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/acriv.org\/WP\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/acriv.org\/WP\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/acriv.org\/WP\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/acriv.org\/WP\/wp-json\/wp\/v2\/comments?post=1884"}],"version-history":[{"count":1,"href":"https:\/\/acriv.org\/WP\/wp-json\/wp\/v2\/pages\/1884\/revisions"}],"predecessor-version":[{"id":1888,"href":"https:\/\/acriv.org\/WP\/wp-json\/wp\/v2\/pages\/1884\/revisions\/1888"}],"wp:attachment":[{"href":"https:\/\/acriv.org\/WP\/wp-json\/wp\/v2\/media?parent=1884"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}