sandwich fix

sandwich fix
A fixing method that dispenses with the transfer of position lines, and so facilitates plotting, is a sandwich fix. The observed altitude of a body varies linearly with time, except near or during meridian passage time. Hence, if two sights are taken on a body, the mean of the two values of an hour angle is at the mean of the midtimes of the two sights. Hence, a pair of sights of a body equally separated from a planned fix time (i.e., one before and one after the fix time) will give a position line without having to take a sight at that time. Thus, by taking a pair of sights on two or more stars so that the mean times coincide with a planned fix time, a simultaneous fix can be obtained. Such fixes are referred to as a sandwich fix. Generally, in this method, four position lines are taken from two sources in such a way that the two pairs of lines are approximately at 90° to one another and the times of the observations are symmetrically spaced at a central time. Meridian passage time is the time at which a celestial body crosses the observer’s celestial meridian.
Graph of altitude against local hour angle.

Aviation dictionary. 2014.

Игры ⚽ Поможем написать курсовую

Look at other dictionaries:

  • Sandwich-structured composite — Composite sandwich structure panel used for testing at NASA A sandwich structured composite is a special class of composite materials that is fabricated by attaching two thin but stiff skins to a lightweight but thick core. The core material is… …   Wikipedia

  • Reuben (Lilo & Stitch) — Disney character name=Reuben (Experiment 625) gender=Male age= Unknown appears= Disney Adventures Magazine , Stitch! The Movie , , Leroy Stitch performer=Rob Paulsen designer=Reuben (also known as Experiment 625) is a character from . He is… …   Wikipedia

  • Android (Betriebssystem) — Android Bildschirmfoto …   Deutsch Wikipedia

  • List of Wizards of Waverly Place characters — …   Wikipedia

  • List of All That Sketches — This is a list of sketches on the Nickelodeon variety show All That.ketches (Seasons 1 10)Noteable Sketches from Seasons 1 6* Good Burger is a sketch that took place at a fast food restaurant. The cashier, Ed played by Kel Mitchell in Seasons 1 5 …   Wikipedia

  • McDonald's products — McDonald s original restaurant in San Bernardino, California served only hamburgers, milkshakes, and french fries. While still based on hamburgers, today s menu includes numerous other items that have been added through the years. Below are… …   Wikipedia

  • List of words having different meanings in British and American English: A–L — Differences between American and British English American English …   Wikipedia

  • Cuban cuisine — Contents 1 Western Cuba cuisine 2 Eastern Cuba cuisine 3 Sandwiches …   Wikipedia

  • Android (operating system) — Android …   Wikipedia

  • List of Corner Gas episodes — This is a list of Corner Gas episodes. All seasons, 1 to 6, are available on DVD. The Season 1 5 DVD s came out in the fall after the next season had began airing, but Season 6 was released on June 9, 2009, only two months after the series finale …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”