FRSI (felt reusable surface insulation, coated Nomex felt) FRSI
Heat-treated meta-aramid (Nomex) felt with a white silicone elastomer coating
Also known as Nomex
FRSI is a white, flexible blanket of heat-treated Nomex felt with a white silicone elastomer coating.
Evidence level
2 of 5
Lab-measured
- 0Predicted only. No one has made it, or no measurement exists.
- 1Calculated. Only calculated or predicted values from sources.
- 2Lab-measured. Measured properties with their conditions stated.
- 3Space-relevant tests. Measured in conditions relevant to space, such as vacuum or atomic oxygen.
- 4Ground-qualified. Qualified for an application on the ground.
- 5Flown or field-proven. Flight or field results exist.
Emissivity
0.8 -
Solar absorptance
0.32 -
Use temperature
Below 700 °F in one NASA source
Thickness
0.16 to 0.4 inch
Recipe, share of the weight
- not statedm-Phenylenediamine
- not statedIsophthaloyl chloride
- not statedSilicone elastomer coating
Best for
White blanket insulation for areas below about 700 °F on a re-entry vehicle, where an emittance of 0.8 is wanted
Weakest at
Few plain numbers for the blanket itself: the NASA database prints density, conductivity and temperature limits only in exponent form, so they are left out
Risk at a glance
- People None found. No hazard data found
- If it fails High. Temperatures above the FRSI design envelope
- Corrosion Low. The Gordon appendix says FRSI does not need rewaterproofing after each flight.
Quick facts: FRSI
| Property | Value | Basis |
|---|---|---|
| Maximum service temperature | 288 to 399 °C | 4 sourced values across conditions |
What is the maximum service temperature of FRSI?
FRSI has a maximum service temperature of 288 to 399 °C. The range covers 4 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.
What is FRSI used for?
Uses recorded in the sources include Upper payload bay doors and upper wing surface of the Space Shuttle orbiter; Thermal blankets on the orbiter payload bay doors, fuselage and upper wing surfaces.
Why it exists
FRSI (felt reusable surface insulation) is a white, flexible blanket of heat-treated Nomex felt with a white silicone elastomer coating. NASA bonded it directly to the Space Shuttle orbiter skin with RTV silicone adhesive, and placed it on surfaces where temperatures stayed below about 700 °F. The NASA sources give few plain numbers for the blanket itself, so this profile records only the values printed in the fetched pages.
Where it's used
Space Shuttle orbiter upper surfaces
NASA KSC says FRSI blankets are now used only on the upper section of the payload bay doors and the inboard sections of the wing upper surface. Wikipedia's Nomex article says Nomex was used as thermal blankets on the payload bay doors, fuselage and upper wing surfaces of the orbiter.
Recipe
Heat-treated meta-aramid (Nomex) felt with a white silicone elastomer coating; the polymer is made from m-phenylenediamine and isophthaloyl chloride
Nomex is a meta-aramid polymer made by condensation of m-phenylenediamine and isophthaloyl chloride, and it is sold as fibre, paper and felt. FRSI is heat-treated Nomex felt with a white silicone elastomer coating, vented by 0.035 inch holes on 6 inch centers.
| Ingredient | Share of the weight | What it does |
|---|---|---|
| m-Phenylenediamine | not stated | Monomer. Wikipedia names it as one of the two monomers that react to form Nomex. |
| Isophthaloyl chloride | not stated | Monomer. The second monomer that reacts with m-phenylenediamine to form Nomex. |
| Silicone elastomer coating | not stated | White outer layer that waterproofs the felt and gives the blanket its thermal and optical properties. |
Weight shares are as printed in the sources.
What it can do
Emissivity
0.8 -
measured
The NASA TPSX entry gives an emissivity of 0.8, with an uncertainty of 0.04 printed in the same row. A NASA shuttle systems page gives the same emittance of 0.8 for FRSI.
Solar absorptance
0.32 -
measured
The NASA shuttle systems page gives a solar absorptance of 0.32, in the same sentence as the emittance of 0.8.
Use temperature
Below 700 °F in one NASA source
The NASA shuttle systems page says FRSI blankets protect areas where temperatures are below 700 F. The Gordon appendix says 750 °F, and the AZoM article gives 371 °C.
Thickness
0.16 to 0.4 inch
NASA gives the installed FRSI thickness as 0.16 to 0.4 inch, set by the heat load encountered during entry.
How it compares
FRSI is a low-temperature blanket: NASA places its use below 700 °F, and it is the lower of the two NASA design limits. The NASA sources disagree on the upper limit, giving 700 °F in the KSC shuttle systems text and 750 °F in the Gordon appendix, with 371 °C in the AZoM article. The NASA TPSX entry is the only database record here that gives emissivity as a table value, and it prints density and conductivity only in exponent form, so this profile does not compare those.
The same measurements for each material, so you can compare them. Each row names the key condition under the value; the full conditions and methods are in the numbered notes under Technical details. Compare every grade in the family.
| Measurement | FRSI |
|---|---|
| Thermal behavior and safety | |
| Emissivity (NASA TPSX table) | 0.8 -1 |
| Emittance of FRSI (NASA shuttle systems text)Value stated in NASA KSC shuttle systems text | 0.8 - |
| Physical and electrical | |
| FRSI thickness on the orbiter (range set by heat load)Range printed in NASA KSC shuttle systems text | 0.16 to 0.4 inch |
| FRSI thickness on the orbiter (TPSX description)Range printed in the NASA Ames TPSX description | 0.16 to 0.4 inch |
| Silicone elastomer coating, as spread before cure | 0.006 to 0.008 inch2 |
| Vent hole spacing in the FRSI coatingPrinted in the NASA Gordon appendix A.4 | 6 inch |
| RTV silicone adhesive bondline under FRSIPrinted in NASA KSC shuttle systems text | 0.2 inch |
| Temperature behavior | |
| Temperature band protected by FRSI blankets (KSC fact sheet) | 350 to 700 °F5 |
| Other measurements | |
| Solar absorptance of FRSIValue stated in NASA KSC shuttle systems text | 0.32 - |
| Vent hole diameter in the FRSI coatingPrinted in the NASA Gordon appendix A.4 | 0.035 inch |
| Upper temperature for FRSI areas (design envelope, Gordon appendix) | < 750 °F3 |
| Upper temperature for FRSI areas (design envelope, KSC shuttle systems text) | < 700 °F4 |
| Upper temperature for FRSI areas (AZoM article)Application limit printed in the AZoM article | < 371 °C |
| RTV silicone adhesive that bonds FRSI, upper temperature with bond strength kept (adhesive, not the felt)Printed in the NASA KSC fact sheet | < 550 °F |
| Waterproofing burn-out temperature for the orbiter thermal protectionPrinted in the NASA KSC fact sheet | 1100 °F |
| Nomex fibre length in the feltPrinted in the NASA Gordon appendix A.4 | 3 inch |
| Nomex fibre fineness in the feltPrinted in the NASA Gordon appendix A.4 | 2 denier |
Why choose it, and why not
Good for
- Surfaces below about 700 °F on a re-entry vehicle, the design use NASA describes for FRSI.
- Places where a white surface with an emissivity of 0.8 is wanted for thermal control, as the NASA sources describe the coating.
Watch out for
- The upper limits disagree between NASA sources: 700 °F in one, 750 °F in another, and 371 °C in the AZoM article.
- The sources disagree on whether FRSI needs rewaterproofing after each flight.
- Density, thermal conductivity and specific heat are printed only in exponent form, so no values are shown for them.
- The RTV adhesive that bonds FRSI is rated to 550 °F. The adhesive, not the felt, sets that bond limit.
FRSI is a white Nomex felt blanket that NASA used on Shuttle upper surfaces. This profile can state its temperature envelope, optical values and installation dimensions from NASA pages only; its density and conductivity are left out until a plain-number source is read.
Technical details
For scientists and researchers. Everything above comes from the record below: every number with its method, its conditions and its source.
Other names and standards
The same grade under other systems, as datasheets and standards print them. Each code was checked against the page it comes from.
| System | Codes |
|---|---|
| Trade name | Nomex |
Notes
The method, full conditions and any caveat for the numbered rows above.
| # | Measurement | Method | Conditions | Caveat |
|---|---|---|---|---|
| 1 | Emissivity (NASA TPSX table) | Tabulated value in the NASA Ames TPSX database entry; the same row prints an uncertainty of 0.04 | table Properties at Standard Conditions (SI units)stated condition true/assumedref column 2 | Uncertainty: 0.04 (printed in the same row) |
| 2 | Silicone elastomer coating, as spread before cure | Process range printed in the NASA Gordon appendix A.4; a process value, not a finished-coating measurement | process Elastomer spread on a screen mesh, then partially curedform Heat-treated Nomex felt | — |
| 3 | Upper temperature for FRSI areas (design envelope, Gordon appendix) | Application limit printed in the NASA Gordon appendix A.4 as less than 750°F | context Upper surface areas where FRSI is used; design envelope, not a material test limit | — |
| 4 | Upper temperature for FRSI areas (design envelope, KSC shuttle systems text) | Application limit printed in NASA KSC shuttle systems text | context Areas the FRSI blankets protect; design envelope, not a material test limit | — |
| 5 | Temperature band protected by FRSI blankets (KSC fact sheet) | Range printed in the NASA KSC Orbiter Thermal Protection System fact sheet | context Orbiter surfaces protected by FRSI blankets; design band | — |
Corrosion and compatibility
What happens when it meets other materials and environments.
| Environment | Concern | What happens |
|---|---|---|
| Water and humidity between flights (NASA Gordon appendix) | low | The Gordon appendix says FRSI does not need rewaterproofing after each flight.1 |
| Water and humidity between flights (KSC fact sheet) | low | The KSC fact sheet says the orbiter thermal protection is rewaterproofed after each flight.2 |
| Heat during processing and service | not rated | The felt is heat treated to reduce shrinkage at high temperature.3 |
| # | Environment | Details | Test conditions |
|---|---|---|---|
| 1 | Water and humidity between flights (NASA Gordon appendix) | The appendix says the Nomex polymer is hygrophobic by nature and the silicone elastomer coating inhibits water intrusion into the felt, so FRSI does not require post-flight rewaterproofing. | basis Statement about the installed FRSI blanket |
| 2 | Water and humidity between flights (KSC fact sheet) | KSC says the waterproofing material burns out at 1,100 °F, which would expose the outer surface to water absorption, so the thermal protection is rewaterproofed after each flight. The sources disagree on whether FRSI needs this step. | basis General statement for the orbiter thermal protection, which KSC lists with FRSI |
| 3 | Heat during processing and service | For FRSI, the Nomex felt is heat treated at 700°F for 30 minutes and then at 750°F for 30 minutes to reduce linear shrinkage at elevated temperatures; the felt darkens to a caramel colour. The appendix gives no degradation rate for the coated blanket. | process Heat treatment before coating |
Risks and side effects
Hazards to people, what happens when a cell overheats, and how the material is handled and stored.
For people
No safety data sheet or GHS record for the coated product was read in this run.
- Fibre family
- DuPont describes Nomex as an inherently flame-resistant, high-temperature fibre that does not melt, drip or support combustion in air.
- Gap
- The product itself has no hazard record in this profile yet.
If the blanket overheats
These are design limits from NASA sources, not test results.
- Envelope
- NASA places FRSI only where temperatures stay below 700 °F in one source and below 750 °F in another.
- Waterproofing
- KSC says the waterproofing burns out at 1,100 °F, which exposes the outer surface to water absorption.
Handling and installation
- Adhesive
- The NASA shuttle systems text bonds FRSI with RTV silicone adhesive at 0.2 inch thickness.
- Edges
- Trimmed to a cavity template and paint-sealed with white silicone elastomer, according to the Gordon appendix.
Test details
The original wording and numbers from the sources, for readers who want them.
Failure risks
| Failure | Trigger and consequence |
|---|---|
| Water absorption if the waterproofing has burned outmoderate severity | Heating to the orbiter waterproofing burn-out temperatureKSC says the waterproofing burns out at 1,100 °F, exposing the outer surface to water absorption until it is rewaterproofed after the flight. |
| Temperatures above the FRSI design envelopehigh severity | Surface heating above 700 °F (NASA shuttle systems text) or 750 °F (Gordon appendix)The NASA sources place FRSI only where temperatures stay below these limits. In hotter areas the orbiter used rigid tiles or other insulation. None of the sources gives a failure test result for FRSI above these limits. |
Handling and storage
- Bond FRSI with RTV silicone adhesive applied at 0.2 inch thickness, as the NASA shuttle systems text describes.
- Trim FRSI to a cavity template and paint-seal the exposed edges with white silicone elastomer, as the NASA appendix describes.
- Keep FRSI areas within their design envelope: 700 °F in the NASA shuttle systems text, 750 °F in the Gordon appendix.
Supply and geography
How common the raw materials are and where they come from.
Nomex (meta-aramid polymer) used for the felt
A synthetic polymer, not a mined material. Wikipedia says Nomex is produced by condensation of m-phenylenediamine and isophthaloyl chloride.
Nomex felt supplier for the Shuttle FRSI (historic)
No current producer share found. NASA KSC lists Albany International Research Co., Dedham, Mass., as the Nomex felt contractor for the Shuttle thermal protection system.
Documents
Datasheets, safety data sheets, papers and standards you can open.
Full record
The complete spore, as stored. Free to reuse under CC-BY-4.0. Images keep the licence shown with each one.
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spore: profile
id: frsi-nomex-felt-blanket
spore_version: 0.2
family: glass-and-composites
name: FRSI (felt reusable surface insulation, coated Nomex felt)
abbreviation: FRSI
role: thermal-protection-blanket
category: thermal-protection
type: flexible-blankets
summary: |
FRSI is a white, flexible blanket of heat-treated Nomex felt with a white silicone elastomer coating. NASA used it on Space Shuttle orbiter upper surfaces where temperatures stayed below about 700 °F. NASA sources give its emittance as 0.8 and its solar absorptance as 0.32. Its density and thermal conductivity are printed in the NASA database only in exponent form, so this profile leaves them out.
best_for: White blanket insulation for areas below about 700 °F on a re-entry vehicle, where an emittance of 0.8 is wanted
weakest_at: 'Few plain numbers for the blanket itself: the NASA database prints density, conductivity and temperature limits only in exponent form, so they are left out'
identity:
formula: Heat-treated meta-aramid (Nomex) felt with a white silicone elastomer coating; the polymer is made from m-phenylenediamine and isophthaloyl chloride
source: wiki-nomex
where: Chemistry paragraph (monomers); the Shuttle use is in the Wikipedia Space Shuttle TPS article
designations:
- system: Trade name
code: Nomex
source: dupont-nomex
where: Page text naming DuPont Nomex and its felt form
tags:
environments:
- re-entry
- low-earth-orbit
applications:
- heat-shields
properties:
- benchmark: thermal_emittance
label: Emissivity (NASA TPSX table)
value: 0.8
unit: '-'
scope: material
conditions:
table: Properties at Standard Conditions (SI units)
stated_condition: true/assumed
ref_column: '2'
method: Tabulated value in the NASA Ames TPSX database entry; the same row prints an uncertainty of 0.04
status: ground
uncertainty: 0.04 (printed in the same row)
source: tpsx
where: Properties at Standard Conditions table, row Emissivity
- benchmark: thermal_emittance
label: Emittance of FRSI (NASA shuttle systems text)
value: 0.8
unit: '-'
scope: material
conditions:
context: Stated for FRSI in the same sentence as the solar absorptance of 0.32
method: Value stated in NASA KSC shuttle systems text
status: ground
source: ksc-sts-sys
where: Section on Felt Reusable Surface Insulation
- benchmark: solar_absorptance
label: Solar absorptance of FRSI
value: 0.32
unit: '-'
scope: material
conditions:
context: Stated in the same sentence as the emittance of 0.8
method: Value stated in NASA KSC shuttle systems text
status: ground
source: ksc-sts-sys
where: Section on Felt Reusable Surface Insulation
- benchmark: thickness
label: FRSI thickness on the orbiter (range set by heat load)
value: 0.16
value_high: 0.4
bound: range
unit: inch
scope: material
conditions:
depends_on: Heat load encountered during entry
form: Installed FRSI blanket
method: Range printed in NASA KSC shuttle systems text
status: ground
source: ksc-sts-sys
where: Section on Felt Reusable Surface Insulation
- benchmark: thickness
label: FRSI thickness on the orbiter (TPSX description)
value: 0.16
value_high: 0.4
bound: range
unit: inch
scope: material
conditions:
depends_on: Heat load encountered during re-entry
form: Installed FRSI blanket
method: Range printed in the NASA Ames TPSX description
status: ground
source: tpsx
where: Description paragraph
- benchmark: coating_thickness
label: Silicone elastomer coating, as spread before cure
value: 0.006
value_high: 0.008
bound: range
unit: inch
scope: material
conditions:
process: Elastomer spread on a screen mesh, then partially cured
form: Heat-treated Nomex felt
method: Process range printed in the NASA Gordon appendix A.4; a process value, not a finished-coating measurement
status: ground
source: gordon
where: A.4 Felt Reusable Surface Insulation, coating paragraph
- benchmark: vent_hole_diameter
label: Vent hole diameter in the FRSI coating
value: 0.035
unit: inch
scope: material
conditions:
feature: Vent holes through the white coating
method: Printed in the NASA Gordon appendix A.4
status: ground
source: gordon
where: A.4, last paragraph
- benchmark: vent_hole_spacing
label: Vent hole spacing in the FRSI coating
value: 6
unit: inch
scope: material
conditions:
feature: Vent holes through the white coating
spacing: On 6 inch centers, as printed
method: Printed in the NASA Gordon appendix A.4
status: ground
source: gordon
where: A.4, last paragraph
- benchmark: max_service_temp
label: Upper temperature for FRSI areas (design envelope, Gordon appendix)
value: 750
bound: upper
unit: °F
scope: material
conditions:
context: Upper surface areas where FRSI is used; design envelope, not a material test limit
method: Application limit printed in the NASA Gordon appendix A.4 as less than 750°F
status: ground
source: gordon
where: A.4, first paragraph
- benchmark: max_service_temp
label: Upper temperature for FRSI areas (design envelope, KSC shuttle systems text)
value: 700
bound: upper
unit: °F
scope: material
conditions:
context: Areas the FRSI blankets protect; design envelope, not a material test limit
method: Application limit printed in NASA KSC shuttle systems text
status: ground
source: ksc-sts-sys
where: Numbered item 6, White blankets of coated Nomex felt
- benchmark: max_service_temp
label: Upper temperature for FRSI areas (AZoM article)
value: 371
bound: upper
unit: °C
scope: material
conditions:
context: Areas where coated Nomex felt FRSI is used; design envelope, not a material test limit
method: Application limit printed in the AZoM article
status: ground
source: azom
where: Section on Coated Nomex Felt Reusable Surface Insulation, temperatures below 371°C
- benchmark: design_temperature_range
label: Temperature band protected by FRSI blankets (KSC fact sheet)
value: 350
value_high: 700
bound: range
unit: °F
scope: material
conditions:
context: Orbiter surfaces protected by FRSI blankets; design band
method: Range printed in the NASA KSC Orbiter Thermal Protection System fact sheet
status: ground
source: ksc-tps
where: Felt Reusable Surface Insulation paragraph
- benchmark: max_service_temp
label: RTV silicone adhesive that bonds FRSI, upper temperature with bond strength kept (adhesive, not the felt)
value: 550
bound: upper
unit: °F
scope: material
conditions:
material: RTV silicone cement that bonds the tiles and blankets
condition: Bond strength retained
method: Printed in the NASA KSC fact sheet
status: ground
source: ksc-tps
where: Paragraph on the RTV adhesive
- benchmark: waterproofing_burnout_temp
label: Waterproofing burn-out temperature for the orbiter thermal protection
value: 1100
unit: °F
scope: material
conditions:
material: Dimethylethoxysilane waterproofing applied after flights
applies_to: Orbiter thermal protection system, as stated by KSC
method: Printed in the NASA KSC fact sheet
status: ground
source: ksc-tps
where: Paragraph on rewaterproofing after each flight
- benchmark: fibre_length
label: Nomex fibre length in the felt
value: 3
unit: inch
scope: material
conditions:
material: Nomex aramid fibres used for the felt
form: Fibre before carding
method: Printed in the NASA Gordon appendix A.4
status: ground
source: gordon
where: A.4, second paragraph
- benchmark: fibre_fineness
label: Nomex fibre fineness in the felt
value: 2
unit: denier
scope: material
conditions:
material: Nomex aramid fibres used for the felt
form: Fibre before carding
method: Printed in the NASA Gordon appendix A.4
status: ground
source: gordon
where: A.4, second paragraph
- benchmark: bondline_thickness
label: RTV silicone adhesive bondline under FRSI
value: 0.2
unit: inch
scope: material
conditions:
adhesive: RTV silicon adhesive
installation: Bonds FRSI directly to the orbiter
method: Printed in NASA KSC shuttle systems text
status: ground
source: ksc-sts-sys
where: Section on Felt Reusable Surface Insulation
corrosion:
- environment: Water and humidity between flights (NASA Gordon appendix)
headline: The Gordon appendix says FRSI does not need rewaterproofing after each flight.
effect: The appendix says the Nomex polymer is hygrophobic by nature and the silicone elastomer coating inhibits water intrusion into the felt, so FRSI does not require post-flight rewaterproofing.
rating: low
conditions:
basis: Statement about the installed FRSI blanket
source: gordon
where: A.4 Felt Reusable Surface Insulation, first paragraph
- environment: Water and humidity between flights (KSC fact sheet)
headline: The KSC fact sheet says the orbiter thermal protection is rewaterproofed after each flight.
effect: KSC says the waterproofing material burns out at 1,100 °F, which would expose the outer surface to water absorption, so the thermal protection is rewaterproofed after each flight. The sources disagree on whether FRSI needs this step.
rating: low
conditions:
basis: General statement for the orbiter thermal protection, which KSC lists with FRSI
source: ksc-tps
where: Paragraph on rewaterproofing after each flight
- environment: Heat during processing and service
headline: The felt is heat treated to reduce shrinkage at high temperature.
effect: For FRSI, the Nomex felt is heat treated at 700°F for 30 minutes and then at 750°F for 30 minutes to reduce linear shrinkage at elevated temperatures; the felt darkens to a caramel colour. The appendix gives no degradation rate for the coated blanket.
rating: unknown
conditions:
process: Heat treatment before coating
source: gordon
where: A.4, third paragraph
risks:
hazards:
- text: The DuPont page describes Nomex as an inherently flame-resistant, high-temperature fibre that does not melt, drip or support combustion in air. No safety data sheet or GHS record for the coated FRSI product was read in this run.
ghs: []
source: dupont-nomex
where: Page text describing Nomex
- text: Wikipedia calls Nomex an inherently flame-resistant fabric and a trademarked term. This describes the fibre family, not a hazard test of the coated FRSI blanket.
ghs: []
source: wiki-nomex
where: Lead paragraph
failure_risks:
- mode: Water absorption if the waterproofing has burned out
trigger: Heating to the orbiter waterproofing burn-out temperature
consequence: KSC says the waterproofing burns out at 1,100 °F, exposing the outer surface to water absorption until it is rewaterproofed after the flight.
severity: moderate
source: ksc-tps
where: Paragraph on rewaterproofing after each flight
- mode: Temperatures above the FRSI design envelope
trigger: Surface heating above 700 °F (NASA shuttle systems text) or 750 °F (Gordon appendix)
consequence: The NASA sources place FRSI only where temperatures stay below these limits. In hotter areas the orbiter used rigid tiles or other insulation. None of the sources gives a failure test result for FRSI above these limits.
severity: high
source: ksc-sts-sys
where: Numbered item 6, White blankets of coated Nomex felt
handling:
- text: Bond FRSI with RTV silicone adhesive applied at 0.2 inch thickness, as the NASA shuttle systems text describes.
source: ksc-sts-sys
where: Section on Felt Reusable Surface Insulation
- text: Trim FRSI to a cavity template and paint-seal the exposed edges with white silicone elastomer, as the NASA appendix describes.
source: gordon
where: A.4, third paragraph (installation)
- text: 'Keep FRSI areas within their design envelope: 700 °F in the NASA shuttle systems text, 750 °F in the Gordon appendix.'
source: ksc-sts-sys
where: Numbered item 6, White blankets of coated Nomex felt
uses:
- application: heat-shields
device: Upper payload bay doors and upper wing surface of the Space Shuttle orbiter
example: KSC says FRSI blankets are now used only on the upper section of the payload bay doors and the inboard sections of the wing upper surface.
source: ksc-tps
where: Felt Reusable Surface Insulation paragraph
- application: heat-shields
device: Thermal blankets on the orbiter payload bay doors, fuselage and upper wing surfaces
example: The Wikipedia Nomex article says Nomex was used as thermal blankets on the payload bay doors, fuselage and upper wing surfaces of the Space Shuttle Orbiter.
source: wiki-nomex
where: Section on the US space program
supply:
- subject: Nomex (meta-aramid polymer) used for the felt
abundance: A synthetic polymer, not a mined material. Wikipedia says Nomex is produced by condensation of m-phenylenediamine and isophthaloyl chloride.
producers: []
substitutes: []
source: wiki-nomex
where: Chemistry paragraph
- subject: Nomex felt supplier for the Shuttle FRSI (historic)
abundance: No current producer share found. NASA KSC lists Albany International Research Co., Dedham, Mass., as the Nomex felt contractor for the Shuttle thermal protection system.
producers: []
substitutes: []
source: ksc-sts-sys
where: Contractors list at the end of the shuttle systems page
documents:
- title: 'NASA Ames TPSX database entry: FRSI Blanket (Nomex Felt)'
type: database
url: https://tpsx.arc.nasa.gov/Material?id=18
- title: Shuttle thermal protection system, Appendix A (NASA KSC public appendix, archived copy)
type: report
url: https://web.archive.org/web/20160307090308/http://science.ksc.nasa.gov/shuttle/nexgen/Nexgen_Downloads/Shuttle_Gordon_TPS-PUBLIC_Appendix.pdf
- title: Space Shuttle systems, KSC shuttle technology page (archived copy)
type: report
url: https://web.archive.org/web/20090715235829/http://science.ksc.nasa.gov/shuttle/technology/sts-newsref/sts_sys.html
- title: Orbiter Thermal Protection System, KSC fact sheet (archived copy)
type: report
url: https://web.archive.org/web/20060909094330/http://www-pao.ksc.nasa.gov/kscpao/nasafact/tps.htm
- title: DuPont Nomex 40th Anniversary page (archived copy)
type: datasheet
url: https://web.archive.org/web/20120217011922/http://www2.dupont.com/Nomex/en_US/news_events/40th_anniv.html
gaps:
- Density, thermal conductivity, specific heat and the multiple-use and single-use temperature limits are printed in the NASA TPSX entry only in exponent form (for example 8.65e+01 kg/m^3); they are left out under the no-exponent rule.
- No plain-number FRSI density, areal mass, tensile strength or tear strength was found in the sources read.
- The NASA TPSX reference list (Kourtides, NASA TM-103925; Rasky 1995; the Rockwell design data book) has no URLs, and those reports were not opened.
- No vacuum, thermal-cycling, outgassing or flight-derived test result for coated FRSI felt was found in the sources read.
- No safety data sheet or GHS record for the coated product was read; hazard entries rest on NASA and DuPont text.
- 'Coverage of the upper surfaces differs between NASA sources: about 25 percent in the KSC fact sheet and nearly 50 percent in the KSC shuttle systems text. Neither figure is recorded as a property.'
- Rewaterproofing after flights is stated for the orbiter thermal protection in the KSC fact sheet but not for FRSI; the Gordon appendix says FRSI does not need it.
- Upper temperature for FRSI areas is 700 °F in the KSC shuttle systems text and 371 °C in the AZoM article, and 750 °F in the Gordon appendix. The sources are recorded side by side, not averaged.
- No current producer or country share was found for Nomex felt. The only named felt contractor is Albany International Research Co., in a Shuttle-era NASA page.
- NASA TPSX prints Emissivity and the KSC shuttle systems text prints Emittance; both are stored under thermal_emittance.
- Thickness, coating, vent-hole and bondline values are NASA descriptions of the Shuttle installation, not manufacturer datasheet values.
- 'Property names not in the canonical list: thickness, coating_thickness, vent_hole_diameter, vent_hole_spacing, design_temperature_range, waterproofing_burnout_temp, fibre_length, fibre_fineness and bondline_thickness.'
- The NASA STS-6 press kit linked from Wikipedia returned an HTML page instead of a PDF, so it was not read. Critical-mineral lists were not checked for an aramid polymer.
- The web search budget for this run ran out, so no further sources were searched for beyond the links in the sources already read.
story:
recipe:
line: Nomex is a meta-aramid polymer made by condensation of m-phenylenediamine and isophthaloyl chloride, and it is sold as fibre, paper and felt. FRSI is heat-treated Nomex felt with a white silicone elastomer coating, vented by 0.035 inch holes on 6 inch centers.
parts:
- name: m-Phenylenediamine
role: Monomer. Wikipedia names it as one of the two monomers that react to form Nomex.
source: wiki-nomex
where: Chemistry paragraph
- name: Isophthaloyl chloride
role: Monomer. The second monomer that reacts with m-phenylenediamine to form Nomex.
source: wiki-nomex
where: Chemistry paragraph
- name: Silicone elastomer coating
role: White outer layer that waterproofs the felt and gives the blanket its thermal and optical properties.
source: gordon
where: A.4 Felt Reusable Surface Insulation
risk_groups:
- title: For people
level: 0
verdict: No hazard data found
lead: No safety data sheet or GHS record for the coated product was read in this run.
points:
- label: Fibre family
line: DuPont describes Nomex as an inherently flame-resistant, high-temperature fibre that does not melt, drip or support combustion in air.
- label: Gap
line: The product itself has no hazard record in this profile yet.
- title: If the blanket overheats
lead: These are design limits from NASA sources, not test results.
points:
- label: Envelope
line: NASA places FRSI only where temperatures stay below 700 °F in one source and below 750 °F in another.
- label: Waterproofing
line: KSC says the waterproofing burns out at 1,100 °F, which exposes the outer surface to water absorption.
- title: Handling and installation
points:
- label: Adhesive
line: The NASA shuttle systems text bonds FRSI with RTV silicone adhesive at 0.2 inch thickness.
- label: Edges
line: Trimmed to a cavity template and paint-sealed with white silicone elastomer, according to the Gordon appendix.
why: FRSI (felt reusable surface insulation) is a white, flexible blanket of heat-treated Nomex felt with a white silicone elastomer coating. NASA bonded it directly to the Space Shuttle orbiter skin with RTV silicone adhesive, and placed it on surfaces where temperatures stayed below about 700 °F. The NASA sources give few plain numbers for the blanket itself, so this profile records only the values printed in the fetched pages.
uses:
- where: Space Shuttle orbiter upper surfaces
line: NASA KSC says FRSI blankets are now used only on the upper section of the payload bay doors and the inboard sections of the wing upper surface. Wikipedia's Nomex article says Nomex was used as thermal blankets on the payload bay doors, fuselage and upper wing surfaces of the orbiter.
can_do:
- label: Emissivity
benchmark: thermal_emittance
line: The NASA TPSX entry gives an emissivity of 0.8, with an uncertainty of 0.04 printed in the same row. A NASA shuttle systems page gives the same emittance of 0.8 for FRSI.
- label: Solar absorptance
benchmark: solar_absorptance
line: The NASA shuttle systems page gives a solar absorptance of 0.32, in the same sentence as the emittance of 0.8.
- label: Use temperature
value: Below 700 °F in one NASA source
line: The NASA shuttle systems page says FRSI blankets protect areas where temperatures are below 700 F. The Gordon appendix says 750 °F, and the AZoM article gives 371 °C.
- label: Thickness
value: 0.16 to 0.4 inch
line: NASA gives the installed FRSI thickness as 0.16 to 0.4 inch, set by the heat load encountered during entry.
compare: 'FRSI is a low-temperature blanket: NASA places its use below 700 °F, and it is the lower of the two NASA design limits. The NASA sources disagree on the upper limit, giving 700 °F in the KSC shuttle systems text and 750 °F in the Gordon appendix, with 371 °C in the AZoM article. The NASA TPSX entry is the only database record here that gives emissivity as a table value, and it prints density and conductivity only in exponent form, so this profile does not compare those.'
compare_rows:
- label: Emissivity
benchmark: thermal_emittance
- label: Solar absorptance
benchmark: solar_absorptance
- label: Upper use temperature
benchmark: max_service_temp
handling:
- 'Keep FRSI areas within their design envelope: 700 °F in the NASA shuttle systems text, and 750 °F in the Gordon appendix.'
- Bond with RTV silicone adhesive at 0.2 inch thickness, as the NASA shuttle systems text describes.
- Trim to a cavity template and paint-seal the exposed edges, as the Gordon appendix describes.
good_for:
- Surfaces below about 700 °F on a re-entry vehicle, the design use NASA describes for FRSI.
- Places where a white surface with an emissivity of 0.8 is wanted for thermal control, as the NASA sources describe the coating.
watch_out:
- 'The upper limits disagree between NASA sources: 700 °F in one, 750 °F in another, and 371 °C in the AZoM article.'
- The sources disagree on whether FRSI needs rewaterproofing after each flight.
- Density, thermal conductivity and specific heat are printed only in exponent form, so no values are shown for them.
- The RTV adhesive that bonds FRSI is rated to 550 °F. The adhesive, not the felt, sets that bond limit.
verdict: FRSI is a white Nomex felt blanket that NASA used on Shuttle upper surfaces. This profile can state its temperature envelope, optical values and installation dimensions from NASA pages only; its density and conductivity are left out until a plain-number source is read.
updated: '2026-11-01'
review:
status: draft
method: assistant
checked_values: 17
unreachable: 0
caveats: 2
note: Read by an AI assistant on 2026-11-01 from NASA, KSC, AZoM, Wikipedia and DuPont pages fetched in this run. Density, conductivity, specific heat and temperature limits in the NASA TPSX entry are printed only in exponent form and are left out.
sources:
tpsx:
title: 'NASA Ames Thermal Protection Materials database: FRSI Blanket (Nomex Felt)'
url: https://tpsx.arc.nasa.gov/Material?id=18
kind: database
license: Public domain (NASA)
azom:
title: Materials Used in Space Shuttle Thermal Protection Systems (AZoM, Alessandro Pirolini)
url: https://www.azom.com/article.aspx?ArticleID=11443
year: 2020
kind: web
license: AZoM terms (cited, not reproduced)
wiki-tps:
title: Space Shuttle thermal protection system (Wikipedia)
url: https://en.wikipedia.org/wiki/Space_Shuttle_thermal_protection_system
kind: web
license: CC BY-SA 4.0 (Wikipedia)
wiki-nomex:
title: Nomex (Wikipedia)
url: https://en.wikipedia.org/wiki/Nomex
kind: web
license: CC BY-SA 4.0 (Wikipedia)
ksc-tps:
title: Orbiter Thermal Protection System, KSC fact sheet (archived copy, 2006 snapshot)
url: https://web.archive.org/web/20060909094330/http://www-pao.ksc.nasa.gov/kscpao/nasafact/tps.htm
year: 2006
kind: report
license: Public domain (NASA)
ksc-sts-sys:
title: Space Shuttle systems, KSC shuttle technology page (archived copy, 2009 snapshot)
url: https://web.archive.org/web/20090715235829/http://science.ksc.nasa.gov/shuttle/technology/sts-newsref/sts_sys.html
year: 2009
kind: report
license: Public domain (NASA)
gordon:
title: Shuttle thermal protection system, Appendix A (NASA KSC public appendix, archived copy)
url: https://web.archive.org/web/20160307090308/http://science.ksc.nasa.gov/shuttle/nexgen/Nexgen_Downloads/Shuttle_Gordon_TPS-PUBLIC_Appendix.pdf
kind: report
license: Public domain (NASA)
dupont-nomex:
title: DuPont Nomex 40th Anniversary page (archived copy, 2012 snapshot)
url: https://web.archive.org/web/20120217011922/http://www2.dupont.com/Nomex/en_US/news_events/40th_anniv.html
year: 2007
kind: web
license: DuPont terms (cited, not reproduced)
license: CC-BY-4.0
References
Every number above carries a reference number. Click one to see the source and where in it the value comes from.
| # | Source | Type | Year | Used for |
|---|---|---|---|---|
| NASA Ames Thermal Protection Materials database: FRSI Blanket (Nomex Felt) | database | 2 values | ||
| Materials Used in Space Shuttle Thermal Protection Systems (AZoM, Alessandro Pirolini) | web | 2020 | 1 value | |
| Space Shuttle thermal protection system (Wikipedia) | web | 0 values | ||
| Nomex (Wikipedia) | web | 4 values | ||
| Orbiter Thermal Protection System, KSC fact sheet (archived copy, 2006 snapshot) | report | 2006 | 6 values | |
| Space Shuttle systems, KSC shuttle technology page (archived copy, 2009 snapshot) | report | 2009 | 9 values | |
| Shuttle thermal protection system, Appendix A (NASA KSC public appendix, archived copy) | report | 9 values | ||
| DuPont Nomex 40th Anniversary page (archived copy, 2012 snapshot) | web | 2007 | 1 value |
Updated