Talk:AVCOAT

Wiki Education Foundation-supported course assignment

This article was the subject of a Wiki Education Foundation-supported course assignment, between 8 January 2019 and 30 April 2019. Further details are available on the course page. Student editor(s): BunnyCuddly. Peer reviewers: BrightSource.

Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 13:12, 16 January 2022 (UTC)

Descriptions

"Avcoat 5026-39/HC-G is an epoxy novolac resin with special additives in a fiberglass honeycomb matrix. In fabrication, the empty honeycomb is bonded to the primary structure and the resin is gunned into each cell individually."

Page.10 - http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19680021275_1968021275.pdf

(FLIGHT TEST ANALYSIS OF APOLLO HEATSHIELD MATERIAL USING THE PACEMAKER VEHICLE SYSTEM - Aug. 1968)

"Avcoat was used for the Apollo capsule heat shield and on select regions of the space shuttle orbiter in its earliest flights. It was put back into production for the study. It is made of silica fibers with an epoxy-novalic resin filled in a fiberglass-phenolic honeycomb and is manufactured directly onto the heat shield substructure and attached as a unit to the crew module during spacecraft assembly."

http://www.nasa.gov/home/hqnews/2009/apr/HQ_09-080_Orion_Heat_Shield.html

(NASA Selects Material for Orion Spacecraft Heat Shield - April. 2009)

--Craigboy (talk) 12:38, 25 November 2010 (UTC)

Thanks User:Craigboy for locating some sources that interested editors may use to improve the article. And good work in your recent edits to start that process. Cheers. N2e (talk) 14:18, 25 November 2010 (UTC)

--BunnyCuddly (talk) 23:21, 1 April 2019 (UTC) --BunnyCuddly (talk) 04:40, 1 May 2019 (UTC) I added some information on this topic from research project.

Confusing ""Avcoat 5026-39/HC-G is an epoxy novolac resin with special additives in a fiberglass honeycomb matrix. " - Is AVCOAT just the filler material or the combination of the filler material and the honeycomb ?

Perhaps the sentence should be "Avcoat 5026-39/HC-G is an epoxy novolac resin with special additives sometimes used in a fiberglass honeycomb matrix." - Rod57 (talk) 20:23, 6 November 2024 (UTC)

Possible rename

I might rename the article simply to AVCOAT and include it's full name in the article.--Craigboy (talk) 12:56, 20 December 2010 (UTC)

• Support the proposal to rename the article. There seems to be no ambiguity about what is being referred to when one says "Avcoat": it is the only Avcoat around, Avcoat 5026-39. Moreover, if other formulations are developed and tested, it would be appropriate to add sections to a single AVCOAT article rather than create a new article for the differing formulation. N2e (talk) 13:35, 20 December 2010 (UTC)

Actually the version originally intended to be used was Avcoat 5026-22 selected in April of 1962 but was replaced by the 5026-39 version before the year ended, this version was significantly lighter (to get the exact numbers check the document below). The earlier version was never used on any mission and has not been considered since the creation of 5026-39.

http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19740007423_1974007423.pdf

--Craigboy (talk) 05:01, 24 December 2010 (UTC)

If there are multiple AVCOAT versions/formulas, as the source suggests, then that is one more very good reason to rename the article as you propose. Then, any notable AVCOAT formulations may be explicated in the single AVCOAT article. Cheers. N2e (talk) 06:27, 31 December 2010 (UTC)

Avcoat may not be suitable for a high speed return from Near Earth Asteroid or Mars

Page. 27

http://www.nasa.gov/pdf/509813main_Human_Space_Exploration_Framework_Summary-2010-01-11.pdf

--Craigboy (talk) 22:05, 14 January 2011 (UTC)

"Earth entry speeds from a nominal Mars return trajectory may be as high as 12 km/s, as compared to 11 km/s for the lunar CEV. This difference will necessitate the development of a higher-density, lightweight TPS."--Craigboy (talk) 08:25, 24 January 2012 (UTC)

precasting into solid blocks for Orion EM-1

NASA's Orion Spacecraft Gets Heat Shield for Daring Test Flight to the Moon says it's precast into solid blocks for Orion EM-1 (unlike even EFT-1) . - Rod57 (talk) 12:42, 7 September 2018 (UTC)

Poorly written parts

Parts of this article read like text has been removed leaving barely intelligible fragments. Either that or it's been edited by a non-native English speaker.
"On the other hand, the Orion heat shield is bonded onto the base of the heat shield." - On the other hand from what? And how can the heat shield be bonded to the heat shield?
"This process of erosion is called “ablation” - where materials are removed by vaporization or erosion by continuous contact with the supersonic velocity of gas flow and high temperature; thus the construction of honeycomb structure was made." - 'Thus' suggests this statement follows from the previous sentence yet it's difficult to see how. The grammar is also poor.
"AVCOAT was first used on the parts of the Apollo spacecraft orbiter and as a unit attached to the crew module in the past." - The parts? What parts? Why 'in the past'? Apollo is an historic programme so it's all in the past.
"NASA's Apollo Flight Test Analysis, AVCOAT 5026-39/HC-G material was tested on the nose cap of a peacemaker vehicle." - This sentence doesn't make sense.
"After the Apollo missions, the production was then put in place for the purpose of studying." - Very poor grammar.
"The Investigating the Thermochemical Response of Avcoat TPS from First Principles for Comparison with EFT-1 Data, things being tested on the heat-shield include" - Another difficult to interpret sentence.

I arrived here following links from today's featured article. Surely a better job could be made? 130.246.149.138 (talk) 11:52, 20 July 2020 (UTC)

I agree. Also confusing or ambiguous was " It is a honeycomb structure. NASA confirmed that this is made of silica fibers with an epoxy novolac resin filled in a fiberglass-phenolic manufactured directly onto the heat shield". What is the honeycomb material, and what is the filler material ? - Rod57 (talk) 20:11, 6 November 2024 (UTC)

[1] says the honeycomb material is "fiber-glass". - Rod57 (talk) 20:37, 6 November 2024 (UTC)

Orion HS Test results

No mention of the first Orion HS test (launched on a Delta IV Heavy, EFT-1) using a filled honeycomb, possibly showing quality problems, since the next HS used on EM-1/Artemis-1 was tiled blocks rather a filled honeycomb. The Artemis-1 HS showed bad spalling after recovery. - Rod57 (talk) 20:17, 6 November 2024 (UTC)