{"id":2642,"date":"2025-11-25T10:43:26","date_gmt":"2025-11-25T09:43:26","guid":{"rendered":"https:\/\/acriv.org\/WP\/?page_id=2642"},"modified":"2025-11-25T10:43:26","modified_gmt":"2025-11-25T09:43:26","slug":"%e2%9b%88%ef%b8%8fmto-impact-sur-les-performances","status":"publish","type":"page","link":"https:\/\/acriv.org\/WP\/%e2%9b%88%ef%b8%8fmto-impact-sur-les-performances\/","title":{"rendered":"\u26c8\ufe0fMTO : IMPACT SUR LES PERFORMANCES"},"content":{"rendered":"<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"800\" height=\"520\" src=\"https:\/\/acriv.org\/WP\/wp-content\/uploads\/2025\/11\/l-avion-bleu-atterrit-sur-la-surface-de-herbe-verte-humide-pneus-d-hydravion-a-cris-piste-mouillee-moteur-reaction-condensation-385341990.webp\" alt=\"\" class=\"wp-image-2643\" style=\"width:247px;height:auto\"\/><\/figure>\n<\/div>\n\n\n<h1 class=\"wp-block-heading\">\u2705 <strong>1. Temp\u00e9rature (densit\u00e9 de l\u2019air : DA \/ Density Altitude)<\/strong><\/h1>\n\n\n\n<h3 class=\"wp-block-heading\">\ud83d\udd39 Impact g\u00e9n\u00e9ral<\/h3>\n\n\n\n<p>Plus il fait chaud \u2192 l\u2019air est moins dense \u2192 performances d\u00e9grad\u00e9es :<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Distance de d\u00e9collage <strong>augmente<\/strong><\/li>\n\n\n\n<li>Distance d\u2019atterrissage <strong>augmente l\u00e9g\u00e8rement<\/strong><\/li>\n\n\n\n<li>Mont\u00e9e <strong>se d\u00e9grade fortement<\/strong><\/li>\n\n\n\n<li>Vitesse indiqu\u00e9e inchang\u00e9e, mais vraie plus \u00e9lev\u00e9e<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">\ud83d\udd39 Ordres de grandeur<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>+10\u00b0C<\/strong> par rapport \u00e0 ISA \u2248 <strong>+300 \u00e0 +400 ft<\/strong> de <em>density altitude<\/em><\/li>\n\n\n\n<li>Distance de d\u00e9collage peut augmenter de <strong>10 \u00e0 25 %<\/strong><\/li>\n\n\n\n<li>Taux de mont\u00e9e diminu\u00e9 de <strong>10 \u00e0 20 %<\/strong> par 1000 ft de DA suppl\u00e9mentaire<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">\u2705 <strong>2. Altitude de la piste<\/strong><\/h1>\n\n\n\n<h3 class=\"wp-block-heading\">\ud83d\udd39 Impact g\u00e9n\u00e9ral<\/h3>\n\n\n\n<p>M\u00eame effet que la temp\u00e9rature (moins d\u2019oxyg\u00e8ne, moins de portance, moins de puissance).<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\ud83d\udd39 Ordres de grandeur<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Chaque <strong>1 000 ft d\u2019altitude<\/strong> ajoute typiquement <strong>8 \u00e0 12 %<\/strong> \u00e0 la distance de d\u00e9collage.<\/li>\n\n\n\n<li>\u00c0 5 000 ft, un avion l\u00e9ger peut voir :\n<ul class=\"wp-block-list\">\n<li>D\u00e9collage augment\u00e9 de <strong>40\u201360 %<\/strong><\/li>\n\n\n\n<li>Taux de mont\u00e9e r\u00e9duit d\u2019environ <strong>30\u201340 %<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">\u2705 <strong>3. Vent<\/strong><\/h1>\n\n\n\n<h3 class=\"wp-block-heading\">\ud83c\udf2c\ufe0f Vent de face<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>R\u00e9duit la distance de d\u00e9collage et d\u2019atterrissage<\/strong><\/li>\n\n\n\n<li>Rep\u00e8re : <strong>10 kt de vent de face \u2192 ~\u221220 %<\/strong> de distance (variable mais bon ordre de grandeur)<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">\ud83c\udf2c\ufe0f Vent arri\u00e8re<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Augmente fortement les distances<\/strong><\/li>\n\n\n\n<li>Rep\u00e8re : m\u00eame <strong>5 kt de vent arri\u00e8re = +20 \u00e0 +30 %<\/strong> de distance<br>\u2192 C\u2019est pourquoi on \u00e9vite les atterrissages\/d\u00e9collages vent arri\u00e8re.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">\ud83c\udf2c\ufe0f Vent traversier<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>N\u2019influence pas la distance mais la <strong>technique et la s\u00e9curit\u00e9<\/strong> (risque de sortie de piste, limitations avion).<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">\u2705 <strong>4. \u00c9tat de la piste<\/strong><\/h1>\n\n\n\n<h3 class=\"wp-block-heading\">\ud83c\udf27\ufe0f Piste mouill\u00e9e<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>D\u00e9collage : <strong>+5 \u00e0 +15 %<\/strong><\/li>\n\n\n\n<li>Atterrissage : <strong>+30 \u00e0 +50 %<\/strong><\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">\u2744\ufe0f Neige \/ herbe haute \/ contamination<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>D\u00e9collage sur herbe (courte et s\u00e8che) : <strong>+10 \u00e0 +20 %<\/strong><\/li>\n\n\n\n<li>Herbe longue ou mouill\u00e9e : <strong>+25 \u00e0 +40 %<\/strong><\/li>\n\n\n\n<li>Neige fondante \/ slush : jusqu\u2019\u00e0 <strong>+60 \u00e0 +100 %<\/strong><\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">\ud83e\uddca Glace<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>D\u00e9collage souvent <strong>d\u00e9conseill\u00e9\/interdit<\/strong><\/li>\n\n\n\n<li>Atterrissage : distances impr\u00e9visibles \u2192 <strong>risque majeur d\u2019aquaplanage\/absence de freinage<\/strong><\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">\u2705 <strong>5. Longueur, largeur et pente de la piste<\/strong><\/h1>\n\n\n\n<h3 class=\"wp-block-heading\">\ud83d\udcc8 Pente<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Pente montante = p\u00e9nalise le d\u00e9collage<\/strong><\/li>\n\n\n\n<li><strong>Pente descendante = avantage le d\u00e9collage mais p\u00e9nalise l\u2019atterrissage<\/strong><\/li>\n\n\n\n<li>Rep\u00e8re :\n<ul class=\"wp-block-list\">\n<li><strong>1 % de pente \u2248 +10 %<\/strong> de distance au d\u00e9collage<\/li>\n\n\n\n<li><strong>1 % de pente \u2248 \u221210 %<\/strong> de distance \u00e0 l\u2019atterrissage (vers le bas de pente)<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">\ud83d\udccf Largeur de piste<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Ne change pas les distances mais influence la <strong>perception<\/strong> (large piste = impression de faible vitesse).<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">\u2705 <strong>6. Masse de l\u2019avion<\/strong><\/h1>\n\n\n\n<h3 class=\"wp-block-heading\">\ud83d\udd39 Impact g\u00e9n\u00e9ral<\/h3>\n\n\n\n<p>C\u2019est <strong>l\u2019un des facteurs les plus importants<\/strong>.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Distance de d\u00e9collage augmente quasi proportionnellement <strong>au carr\u00e9 de la masse<\/strong><\/li>\n\n\n\n<li>Distance d\u2019atterrissage augmente proportionnellement \u00e0 la <strong>masse<\/strong><\/li>\n\n\n\n<li>Mont\u00e9e se d\u00e9grade s\u00e9v\u00e8rement<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">\ud83d\udd39 Ordres de grandeur<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>+10 % de masse \u2192 +20 %<\/strong> de distance de d\u00e9collage<\/li>\n\n\n\n<li><strong>+10 % de masse \u2192 +10 %<\/strong> de distance d\u2019atterrissage<\/li>\n\n\n\n<li>Taux de mont\u00e9e r\u00e9duit de <strong>10\u201325 %<\/strong><\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">\u2705 <strong>7. \u00c9tat de la surface de l\u2019avion<\/strong><\/h1>\n\n\n\n<h3 class=\"wp-block-heading\">\u2744\ufe0f Givrage \/ givre r\u00e9siduel<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>M\u00eame une fine pellicule peut augmenter la tra\u00een\u00e9e de <strong>30 %<\/strong><\/li>\n\n\n\n<li>D\u00e9collage peut devenir <strong>impossible<\/strong><\/li>\n\n\n\n<li>Taux de mont\u00e9e dramatiquement r\u00e9duit<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">\ud83e\uddfc Avion sale (insectes sur le bord d\u2019attaque, poussi\u00e8re, peinture poreuse)<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Peut r\u00e9duire le coefficient de portance maximum (<strong>CLmax<\/strong>) de <strong>3 \u00e0 10 %<\/strong><\/li>\n\n\n\n<li>D\u00e9crochage plus t\u00f4t, distances augment\u00e9es<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">\u2705 <strong>8. R\u00e9glage moteur &amp; performance moteur<\/strong><\/h1>\n\n\n\n<h3 class=\"wp-block-heading\">\ud83d\udd39 Injection ou carburateur<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Air chaud\/humide \u2192 puissance r\u00e9duite<\/li>\n\n\n\n<li>R\u00e9glage mixture crucial en altitude<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">\ud83d\udd39 Pertes typiques<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Perte de <strong>3 % de puissance par 1 000 ft<\/strong> environ (moteur atmosph\u00e9rique)<\/li>\n\n\n\n<li>Perte de <strong>1 % de puissance par +5\u00b0C<\/strong><\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">\u2705 <strong>9. Technique du pilote<\/strong><\/h1>\n\n\n\n<p>M\u00eame conditions m\u00e9t\u00e9o \u2192 performances tr\u00e8s diff\u00e9rentes.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Facteurs impactant :<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Rotation trop t\u00f4t \u2192 <strong>ralentissement \/ allongement<\/strong><\/li>\n\n\n\n<li>Rotation trop tard \u2192 <strong>balayage piste \/ risque de sortie<\/strong><\/li>\n\n\n\n<li>Vitesse tenue en mont\u00e9e \u2192\n<ul class=\"wp-block-list\">\n<li>Trop \u00e9lev\u00e9e : mont\u00e9e faible<\/li>\n\n\n\n<li>Trop faible : proche du d\u00e9crochage<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li>En atterrissage :\n<ul class=\"wp-block-list\">\n<li>Approche trop rapide = <strong>longueur ++<\/strong><\/li>\n\n\n\n<li>Tenue \u00e0 la hauteur = <strong>longueur ++<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Ordres de grandeur<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>+5 kt en courte finale \u2192 <strong>+15 \u00e0 +25 %<\/strong> de distance d\u2019atterrissage<\/li>\n\n\n\n<li>Mauvaise tenue de vitesse au d\u00e9collage \u2192 +20 % facilement<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">\ud83d\udca1 <strong>R\u00e9sum\u00e9 ultra-rapide<\/strong><\/h1>\n\n\n\n<figure class=\"wp-block-table\"><table><thead><tr><th>Facteur<\/th><th>Impact principal<\/th><th>Ordre de grandeur<\/th><\/tr><\/thead><tbody><tr><td>Temp\u00e9rature\/DA<\/td><td>D\u00e9collage \u2191, mont\u00e9e \u2193<\/td><td>+10 \u00e0 +25 %<\/td><\/tr><tr><td>Altitude<\/td><td>D\u00e9collage \u2191, mont\u00e9e \u2193<\/td><td>+10 % \/ 1000 ft<\/td><\/tr><tr><td>Vent face<\/td><td>Distances \u2193<\/td><td>\u221220 % \/ 10 kt<\/td><\/tr><tr><td>Vent arri\u00e8re<\/td><td>Distances \u2191<\/td><td>+20 \u00e0 +30 % \/ 5 kt<\/td><\/tr><tr><td>Piste mouill\u00e9e<\/td><td>Atterrissage \u2191<\/td><td>+30 \u00e0 +50 %<\/td><\/tr><tr><td>Herbe<\/td><td>D\u00e9collage \u2191<\/td><td>+10 \u00e0 +40 %<\/td><\/tr><tr><td>Masse<\/td><td>Toutes distances \u2191<\/td><td>+20 % \/ +10 % masse<\/td><\/tr><tr><td>Givrage<\/td><td>Performances \u2193\u2193\u2193<\/td><td>+30 % drag min.<\/td><\/tr><tr><td>Technique pilote<\/td><td>Tr\u00e8s variable<\/td><td>\u00b120\u201330 %<\/td><\/tr><\/tbody><\/table><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>\u2705 1. Temp\u00e9rature (densit\u00e9 de l\u2019air : DA \/ Density Altitude) \ud83d\udd39 Impact g\u00e9n\u00e9ral Plus il fait chaud \u2192 l\u2019air est moins dense \u2192 performances d\u00e9grad\u00e9es : \ud83d\udd39 Ordres de grandeur \u2705 2. Altitude de la piste \ud83d\udd39 Impact g\u00e9n\u00e9ral M\u00eame effet que la temp\u00e9rature (moins d\u2019oxyg\u00e8ne, moins de portance, moins de puissance). \ud83d\udd39 Ordres de grandeur \u2705 3. Vent<\/p>\n<p><a class=\"more-link\" href=\"https:\/\/acriv.org\/WP\/%e2%9b%88%ef%b8%8fmto-impact-sur-les-performances\/\">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-2642","page","type-page","status-publish","hentry"],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/acriv.org\/WP\/wp-json\/wp\/v2\/pages\/2642","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=2642"}],"version-history":[{"count":1,"href":"https:\/\/acriv.org\/WP\/wp-json\/wp\/v2\/pages\/2642\/revisions"}],"predecessor-version":[{"id":2644,"href":"https:\/\/acriv.org\/WP\/wp-json\/wp\/v2\/pages\/2642\/revisions\/2644"}],"wp:attachment":[{"href":"https:\/\/acriv.org\/WP\/wp-json\/wp\/v2\/media?parent=2642"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}