LI-900 has a bulk density of 144.2 kg/m3 (9 lb/ft3). It was for this reason that it was called the LI-900. It is made from 99.9% pure silica glass fibres, and is 94% air by volume. An LI-900 tile can be heated to 1,204 °C (1,477 K; 2,199 °F) and then immediately plunged into cold water and suffer no damage.[2]
Black and white tiles were used on the Space Shuttle to control the temperature of the vehicle while in orbit.[citation needed]
White tiles (known as LRSI) were used mainly on the upper surface and have higher thermal reflectivity. These are therefore pointed towards the sun in order to minimize solar gain.
Black tiles (known as HRSI) are optimized for maximum emissivity, which means they lose heat faster than white tiles. This property is required in order to maximise heat rejection during re-entry.
There are typically 20,000 HRSI LI-900 tiles on a Space Shuttle, and 725 LRSI LI-900 tiles.
As a result of optimizing its thermal properties, overall strength was reduced. The tile was therefore not suitable to be used in high-stress areas such as around the landing gear doors and windows. To solve this, a higher strength version of the LI-900 material was produced, with a bulk density of 352.4 kg/m3 (22 lb/ft3), which was called the LI-2200.[2] This tile provided the strength and insulating properties, but with a considerable weight penalty.
this, article, includes, list, general, references, lacks, sufficient, corresponding, inline, citations, please, help, improve, this, article, introducing, more, precise, citations, january, 2011, learn, when, remove, this, template, message, type, reusable, s. This article includes a list of general references but it lacks sufficient corresponding inline citations Please help to improve this article by introducing more precise citations January 2011 Learn how and when to remove this template message LI 900 is a type of reusable surface insulation tile developed and manufactured by Lockheed Missiles and Space Company in Sunnyvale California It was designed for use on the Space Shuttle orbiter as part of its thermal protection system to minimize thermal conductivity while providing maximum thermal shock resistance 2 Simulation of the outside of the Shuttle as it heats up to over 1 500 C 1 during re entry Contents 1 Statistics 2 Problems 2 1 Strength 3 See also 4 References 5 SourcesStatistics EditLI 900 has a bulk density of 144 2 kg m3 9 lb ft3 It was for this reason that it was called the LI 900 It is made from 99 9 pure silica glass fibres and is 94 air by volume An LI 900 tile can be heated to 1 204 C 1 477 K 2 199 F and then immediately plunged into cold water and suffer no damage 2 Black and white tiles were used on the Space Shuttle to control the temperature of the vehicle while in orbit citation needed White tiles known as LRSI were used mainly on the upper surface and have higher thermal reflectivity These are therefore pointed towards the sun in order to minimize solar gain Black tiles known as HRSI are optimized for maximum emissivity which means they lose heat faster than white tiles This property is required in order to maximise heat rejection during re entry There are typically 20 000 HRSI LI 900 tiles on a Space Shuttle and 725 LRSI LI 900 tiles Problems Edit A used tile from Atlantis Strength Edit As a result of optimizing its thermal properties overall strength was reduced The tile was therefore not suitable to be used in high stress areas such as around the landing gear doors and windows To solve this a higher strength version of the LI 900 material was produced with a bulk density of 352 4 kg m3 22 lb ft3 which was called the LI 2200 2 This tile provided the strength and insulating properties but with a considerable weight penalty See also EditSpace Shuttle thermal protection system Atmospheric reentryReferences Edit Space Shuttle Orbiter Systems NASA 2000 Retrieved 2009 12 06 a b c Orbiter Thermal Protection System Thermal Materials PDF NASA 2006 p 3 Retrieved 2008 06 05 Sources EditNASA facts on the Orbiter Thermal Protection System Research and technology report on shuttle materials resistant to MMOD Retrieved from https en wikipedia org w index php title LI 900 amp oldid 1121562744, wikipedia, wiki, book, books, library,
