{"id":394,"date":"2015-11-25T14:43:07","date_gmt":"2015-11-25T22:43:07","guid":{"rendered":"http:\/\/tghaviation.com\/aircraft-instrument-services\/?p=394"},"modified":"2024-08-08T10:53:02","modified_gmt":"2024-08-08T17:53:02","slug":"getting-to-know-your-kollsman-window-and-barber-pole","status":"publish","type":"post","link":"https:\/\/tghaviation.com\/aircraft-instrument-services\/getting-to-know-your-kollsman-window-and-barber-pole\/","title":{"rendered":"Getting to know your Kollsman Window and Barber Pole"},"content":{"rendered":"<h5>Getting to know your Kollsman Window and Barber Pole<\/h5>\n<h5><\/h5>\n<p>&nbsp;<\/p>\n<h5><\/h5>\n<h5><\/h5>\n<p><strong>\u00a0Reading the Kollsman Window ( Barometric Reading)<\/strong><\/p>\n<p>The Kollsman window is located at the 3 o\u2019clock position on the altimeter dial.\u00a0This window allows access to read a sub-dial, which contains the barometric readings. The arrowhead indice located precisely at the 3 o\u2019clock position on the altimeter\u2019s main dial is used as the reference point for reading the barometric sub-dial. Most altimeters will have a sub-dial, which covers the readings from 28.1 InHg (inches of mercury) to 31.0 InHg. On the sub-dial each major indice is read as 0.1 InHg, each minor indice is read as 0.02 InHg.<\/p>\n<p>The Altimeter in Figure 1 reads 29.92 InHg<\/p>\n<p>&nbsp;<\/p>\n<p>As previously, stated, weather conditions will greatly affect the pressure of the atmosphere (the barometric reading). Altimeters report altitude as a function of atmospheric pressure. Typically pilots will obtain a local barometric reading from the nearest airport. They will then set the Kollsman window to the setting that they received. This action will adjust the altimeter reading, eliminating error due to local weather conditions.<\/p>\n<p>Some altimeters will have a Kollsman Window, which reads out in milli-bars in lieu of InHg. These are usually altimeters designated for use in Europe. However use of milli-bars has become more common in the U.S. during the last few years. Milli-Bars is just another unit of measurement, 1013.2 milli-bars = 29.92 InHg.<\/p>\n<p><strong>\u00a0<\/strong><\/p>\n<p><strong>The Barber Pole<\/strong><\/p>\n<p>The \u201cBarber Pole\u201d on the face of the altimeter is visible only when the altitude is above sea level. When the altitude is below sea level the barber pole is no longer visible. This is provided to avoid the error of reading \u20131,000 Ft. as being +10,000 Ft.<\/p>\n<p><a href=\"http:\/\/tghaviation.com\/aircraft-instrument-services\/wp-content\/uploads\/barber_pole-2.png\" target=\"_blank\" rel=\"noopener\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-medium wp-image-410\" src=\"http:\/\/tghaviation.com\/aircraft-instrument-services\/wp-content\/uploads\/barber_pole-2.png\" alt=\"barber_pole\" width=\"500\" height=\"500\" \/><\/a><\/p>\n<h5><\/h5>\n","protected":false},"excerpt":{"rendered":"<p>Getting to know your Kollsman Window and Barber Pole &nbsp; \u00a0Reading the Kollsman Window ( Barometric Reading) The Kollsman window is located at the 3 o\u2019clock position on the altimeter dial.\u00a0This window allows access to read a sub-dial, which contains the barometric readings. The arrowhead indice located precisely at the 3 o\u2019clock position on the &hellip; <a href=\"https:\/\/tghaviation.com\/aircraft-instrument-services\/getting-to-know-your-kollsman-window-and-barber-pole\/\" class=\"more-link\">Continue reading <span class=\"screen-reader-text\">Getting to know your Kollsman Window and Barber Pole<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_links_to":"","_links_to_target":""},"categories":[9],"tags":[12,44,43,39,40,42,37,30,41,38],"class_list":["post-394","post","type-post","status-publish","format-standard","hentry","category-tgh-aviation-blog","tag-altimeter","tag-altitude","tag-atmospheric-pressure","tag-barber-pole","tag-barometriv-reading","tag-inches-of-mercury","tag-kollsman","tag-sea-level","tag-sub-dial","tag-wimdow"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/tghaviation.com\/aircraft-instrument-services\/wp-json\/wp\/v2\/posts\/394","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/tghaviation.com\/aircraft-instrument-services\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/tghaviation.com\/aircraft-instrument-services\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/tghaviation.com\/aircraft-instrument-services\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/tghaviation.com\/aircraft-instrument-services\/wp-json\/wp\/v2\/comments?post=394"}],"version-history":[{"count":22,"href":"https:\/\/tghaviation.com\/aircraft-instrument-services\/wp-json\/wp\/v2\/posts\/394\/revisions"}],"predecessor-version":[{"id":1748,"href":"https:\/\/tghaviation.com\/aircraft-instrument-services\/wp-json\/wp\/v2\/posts\/394\/revisions\/1748"}],"wp:attachment":[{"href":"https:\/\/tghaviation.com\/aircraft-instrument-services\/wp-json\/wp\/v2\/media?parent=394"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/tghaviation.com\/aircraft-instrument-services\/wp-json\/wp\/v2\/categories?post=394"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/tghaviation.com\/aircraft-instrument-services\/wp-json\/wp\/v2\/tags?post=394"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}