{
  "spore": "profile",
  "id": "afrsi-blanket",
  "spore_version": "0.2",
  "family": "glass-and-composites",
  "name": "AFRSI (advanced flexible reusable surface insulation blanket)",
  "abbreviation": "AFRSI",
  "role": "thermal-protection-blanket",
  "category": "thermal-protection",
  "type": "flexible-blankets",
  "summary": "AFRSI is a quilted flexible blanket of woven silica fabric, fibrous silica batting and woven S-glass, sewn with silica thread. NASA's TPSX record gives its thru-the-thickness thermal conductivity as 0.0329 W/m-K and its multiple-use temperature limit as 922 K. The blanket was used on many Shuttle Orbiter leeside surfaces. TPSX says it costs less to install than tile thermal protection but is less suitable for high or fluctuating aerodynamic loads, and that it becomes brittle after thermal exposure.\n",
  "best_for": "Reusable insulation on surfaces without high or fluctuating aerodynamic loads, where the installed cost matters more than surface strength",
  "weakest_at": "Aerodynamic loads (TPSX says it is less suitable than tile for high or fluctuating loads) and brittleness after thermal exposure",
  "identity": {
    "formula": "Woven silica (Astroquartz) outer fabric, fibrous silica batting (Q-felt) and woven S-glass inner fabric, sewn with Astroquartz thread",
    "designations": [
      {
        "system": "Trade name",
        "code": "Shuttle AFRSI",
        "source": "tpsx-afrsi",
        "where": "Description, which says it is also called Type II or Shuttle AFRSI"
      },
      {
        "system": "Trade name",
        "code": "Type II",
        "source": "tpsx-afrsi",
        "where": "Description, which says it is also called Type II or Shuttle AFRSI"
      }
    ],
    "source": "tpsx-afrsi",
    "where": "Description and Composition"
  },
  "tags": {
    "environments": [
      "re-entry"
    ],
    "stresses": [
      "extreme-heat"
    ],
    "applications": [
      "heat-shields"
    ]
  },
  "properties": [
    {
      "benchmark": "additive_areal_weight",
      "value": 1.46,
      "bound": "exact",
      "unit": "kg/m^2",
      "scope": "material",
      "conditions": {
        "basis": "Additive areal weight, added to density times thickness to give total areal weight (TPSX footnote 2)",
        "uncertainty_as_printed": "N/A",
        "stp": "assumed/assumed in TPSX STP column"
      },
      "method": "TPSX Properties at Standard Conditions table. TPSX gives no measurement method, so the status is set to calculated.",
      "status": "calculated",
      "source": "tpsx-afrsi",
      "where": "Properties at Standard Conditions table, Additive Areal Weight row (footnote 2)",
      "source_detail": {
        "title": "NASA Ames TPSX material record: AFRSI Blanket (Material id 12)",
        "id": "TPSX Material id=12; record last modified 2001-10-01; property table last modified 2006-01-05",
        "url": "https://tpsx.arc.nasa.gov/Material?id=12",
        "year": 2006,
        "kind": "database",
        "license": "public domain (NASA)"
      }
    },
    {
      "benchmark": "thermal_conductivity",
      "value": 0.0329,
      "bound": "exact",
      "unit": "W/m-K",
      "scope": "material",
      "conditions": {
        "direction": "Through the thickness, normal to the blanket plane only",
        "stp": "TRUE in TPSX STP column",
        "uncertainty_as_printed": "1.64e-03 W/m-K"
      },
      "method": "TPSX Properties at Standard Conditions table. The page says conductivity is directional and gives only the normal-to-plane value (footnote 3).",
      "status": "ground",
      "source": "tpsx-afrsi",
      "where": "Properties at Standard Conditions table, Thermal Conductivity, Thru-the-Thickness row (footnote 3)",
      "source_detail": {
        "title": "NASA Ames TPSX material record: AFRSI Blanket (Material id 12)",
        "id": "TPSX Material id=12; record last modified 2001-10-01; property table last modified 2006-01-05",
        "url": "https://tpsx.arc.nasa.gov/Material?id=12",
        "year": 2006,
        "kind": "database",
        "license": "public domain (NASA)"
      }
    },
    {
      "benchmark": "emissivity",
      "value": 0.87,
      "bound": "exact",
      "unit": "-",
      "scope": "material",
      "conditions": {
        "coating": "C-9 coated blanket with Astroquartz outer fabric (the page gives no uncoated value)",
        "uncertainty_as_printed": "4.35e-02"
      },
      "method": "TPSX Properties at Standard Conditions table, footnote 4, which says the emissivity values are for the C-9 coated blanket with Astroquartz outer fabric.",
      "status": "ground",
      "source": "tpsx-afrsi",
      "where": "Properties at Standard Conditions table, Emissivity row (footnote 4)",
      "source_detail": {
        "title": "NASA Ames TPSX material record: AFRSI Blanket (Material id 12)",
        "id": "TPSX Material id=12; record last modified 2001-10-01; property table last modified 2006-01-05",
        "url": "https://tpsx.arc.nasa.gov/Material?id=12",
        "year": 2006,
        "kind": "database",
        "license": "public domain (NASA)"
      }
    },
    {
      "benchmark": "replacement_fraction_per_flight",
      "value": 0.018,
      "bound": "exact",
      "unit": "-",
      "scope": "material",
      "conditions": {
        "basis": "Fraction of the blanket replaced per flight, based on Shuttle experience",
        "uncertainty_as_printed": "9.00e-04"
      },
      "method": "TPSX lists the measurement type as predicted (footnote 10).",
      "status": "calculated",
      "source": "tpsx-afrsi",
      "where": "Properties at Standard Conditions table, Replacement Fraction per Flight row (footnote 10)",
      "source_detail": {
        "title": "NASA Ames TPSX material record: AFRSI Blanket (Material id 12)",
        "id": "TPSX Material id=12; record last modified 2001-10-01; property table last modified 2006-01-05",
        "url": "https://tpsx.arc.nasa.gov/Material?id=12",
        "year": 2006,
        "kind": "database",
        "license": "public domain (NASA)"
      }
    },
    {
      "benchmark": "thickness",
      "value": 0.24,
      "value_high": 1.94,
      "bound": "exact",
      "unit": "inch",
      "scope": "material",
      "conditions": {
        "basis": "Demonstrated thickness range; the nominal thickness is 1.0 inch",
        "nominal_thickness": "1.0 inch"
      },
      "method": "TPSX footnote 1 to the Properties at Standard Conditions table, which gives the nominal and demonstrated thicknesses.",
      "status": "ground",
      "source": "tpsx-afrsi",
      "where": "Properties at Standard Conditions table, footnote 1",
      "source_detail": {
        "title": "NASA Ames TPSX material record: AFRSI Blanket (Material id 12)",
        "id": "TPSX Material id=12; record last modified 2001-10-01; property table last modified 2006-01-05",
        "url": "https://tpsx.arc.nasa.gov/Material?id=12",
        "year": 2006,
        "kind": "database",
        "license": "public domain (NASA)"
      }
    }
  ],
  "corrosion": [
    {
      "environment": "Thermal exposure (reentry heating cycles)",
      "headline": "TPSX says the blanket becomes brittle after thermal exposure.",
      "effect": "The TPSX description says AFRSI 'becomes brittle after thermal exposure'. The record gives no temperature, time or cycle count for when this starts.",
      "rating": "moderate",
      "conditions": {
        "exposure": "Thermal exposure; temperature, duration and number of cycles not stated on the TPSX record"
      },
      "source": "tpsx-afrsi",
      "where": "Description"
    }
  ],
  "risks": {
    "hazards": [
      {
        "text": "PubChem's aggregated record for silica (CID 24261), the chemical behind silica fibre, lists it as not classified. 7724 of 9127 company reports say it does not meet GHS hazard criteria.",
        "ghs": [],
        "source": "pubchem-silica",
        "where": "GHS Classification, top-level entry (EC 231-545-4)"
      },
      {
        "text": "A separate PubChem entry for amorphous silica (EC 601-216-3) lists H315 (causes skin irritation), H319 (causes serious eye irritation) and H335 (may cause respiratory irritation). The record does not say which silica form the AFRSI fibres are.",
        "ghs": [
          "H315",
          "H319",
          "H335"
        ],
        "source": "pubchem-silica",
        "where": "GHS Classification, amorphous silica entry (EC 601-216-3)"
      }
    ],
    "failure_risks": [
      {
        "mode": "Brittleness after thermal exposure",
        "trigger": "Thermal exposure; the TPSX record gives no dose",
        "consequence": "The blanket becomes brittle, according to the TPSX description.",
        "severity": "moderate",
        "source": "tpsx-afrsi",
        "where": "Description"
      },
      {
        "mode": "Poor tolerance of high or fluctuating aerodynamic loads",
        "trigger": "High or fluctuating aerodynamic loads",
        "consequence": "TPSX says AFRSI is less suitable for these loads than tile thermal protection. The record gives no failure load.",
        "severity": "moderate",
        "source": "tpsx-afrsi",
        "where": "Description"
      }
    ],
    "side_effects": [
      {
        "text": "TPSX says installation time, inspection and repair time, and replacement fraction 'may vary drastically' if the environment differs from the Shuttle's.",
        "affects": "Maintenance planning outside the Shuttle environment",
        "source": "tpsx-afrsi",
        "where": "Footnotes 8, 9 and 10 of the Properties at Standard Conditions table"
      }
    ],
    "handling": [
      {
        "text": "Wikipedia says AFRSI required much less maintenance than the LRSI tiles it replaced, and had about the same thermal properties.",
        "source": "wiki-sts-tps",
        "where": "Non-tile TPS, Flexible Insulation Blankets/AFRSI subsection"
      },
      {
        "text": "TPSX gives inspection and repair time of 37200 s/m^2 per flight, a predicted value based on Shuttle experience.",
        "source": "tpsx-afrsi",
        "where": "Properties at Standard Conditions table, Inspection/Repair Time per Flight row"
      }
    ],
    "mitigations": [
      {
        "text": "Keep the blanket below its multiple-use temperature limit of 922 K. TPSX gives the single-use limit as 1090 K.",
        "source": "tpsx-afrsi",
        "where": "Properties at Standard Conditions table, Multiple Use and Single Use Temperature Limit rows"
      },
      {
        "text": "Place it on leeside surfaces: TPSX says AFRSI was used on many Shuttle Orbiter leeside surfaces and is less suitable for high or fluctuating aerodynamic loads.",
        "source": "tpsx-afrsi",
        "where": "Description"
      }
    ]
  },
  "uses": [
    {
      "application": "heat-shields",
      "device": "Space Shuttle Orbiter leeside surfaces",
      "example": "TPSX says AFRSI was used on many Shuttle Orbiter leeside surfaces. It has a lower installed cost than tile thermal protection.",
      "source": "tpsx-afrsi",
      "where": "Description"
    },
    {
      "application": "heat-shields",
      "device": "Orbital Maneuvering System pods, then tile replacement on Columbia",
      "example": "Wikipedia says AFRSI was first used on the OMS pods of Challenger, used much more extensively from Discovery onward, and replaced many LRSI tiles on Columbia after the loss of Challenger.",
      "source": "wiki-sts-tps",
      "where": "Non-tile TPS, Flexible Insulation Blankets/AFRSI subsection"
    }
  ],
  "supply": [],
  "media": [],
  "documents": [
    {
      "title": "NASA Ames TPSX material record: AFRSI Blanket (Material id 12)",
      "type": "database",
      "url": "https://tpsx.arc.nasa.gov/Material?id=12",
      "year": 2006
    },
    {
      "title": "NASA Ames TPSX material record: AFRSI-2500 Blanket (Material id 14), a separate grade",
      "type": "database",
      "url": "https://tpsx.arc.nasa.gov/Material?id=14",
      "year": 2006
    },
    {
      "title": "Composite Multilayer Insulations for Thermal Protection of Aerospace Vehicles (NASA TM 101071)",
      "type": "report",
      "url": "https://ntrs.nasa.gov/api/citations/19900000867/downloads/19900000867.pdf",
      "year": 1989
    },
    {
      "title": "PubChem: Silica (CID 24261), GHS classification",
      "type": "database",
      "url": "https://pubchem.ncbi.nlm.nih.gov/compound/24261",
      "year": 2026
    }
  ],
  "gaps": [
    "Supply: no producer, feedstock or country data for Astroquartz, Q-felt or S-glass was read in this run, so the supply list is empty.",
    "Recipe: no atomic or mass shares for the silica, glass or thread constituents were read, so the recipe parts carry no atoms or atomic weights.",
    "Names not in spores/property-canon.yaml, used in snake_case: additive_areal_weight, emissivity, multiple_use_temperature_limit, single_use_temperature_limit, purchase_cost, installation_time, inspection_repair_time_per_flight, replacement_fraction_per_flight, thickness.",
    "TPSX reuse flight limit is printed as 0.0 with no explanation, so it is left out.",
    "No flight measurement of AFRSI density, conductivity or temperature was read in this run. Cost, installation, inspection and replacement values are predicted from Shuttle experience.",
    "The Boeing Shuttle Operational Data Book, which TPSX cites for the temperature limits, was not opened.",
    "No oxidation, humidity, atomic-oxygen or coating-durability test result for AFRSI was read in this run. The only ageing statement is the TPSX brittleness line.",
    "The NASA TM 101071 (1989) compares a composite multilayer insulation with an AFRSI of equal thickness and density. Its AFRSI backface-temperature results are in figures and garbled PDF text, so no numbers were taken from it.",
    "The hazard entries come from the PubChem silica summary, not from a supplier safety data sheet for an AFRSI blanket. The H315, H319 and H335 codes belong to the amorphous silica entry.",
    "AFRSI-2500 (TPSX id 14) and AFRSI-2200 (TPSX id 13) are separate grades with their own records. Their values are not used in this profile."
  ],
  "story": {
    "why": "AFRSI, the advanced flexible reusable surface insulation, is a quilted blanket of silica fabric and silica batting. A thermal protection system (TPS) is the outer layer that keeps the vehicle structure within its temperature limit during reentry. TPSX says AFRSI is used on many Shuttle Orbiter leeside surfaces. Wikipedia says it replaced many of the tiles on Columbia after the loss of Challenger. TPSX also says it costs less to install than tile TPS, but is less suitable for high or fluctuating aerodynamic loads.",
    "uses": [
      {
        "where": "Shuttle Orbiter leeside surfaces",
        "line": "TPSX says AFRSI was used on many Shuttle Orbiter leeside surfaces. It has a lower installed cost than tile thermal protection, according to the same record."
      },
      {
        "where": "OMS pods, then tile replacement",
        "line": "Wikipedia says AFRSI was first used on the OMS pods of Challenger and was used much more extensively from Discovery onward. It replaced many LRSI tiles on Columbia after the loss of Challenger."
      }
    ],
    "can_do": [
      {
        "label": "Thermal conductivity",
        "line": "Through the thickness, AFRSI conducts heat at 0.0329 W/m-K at standard conditions, per TPSX. The record gives only the normal-to-plane value.",
        "benchmark": "thermal_conductivity",
        "scope": "material",
        "value": "0.0329 W/m-K"
      },
      {
        "label": "Use temperature",
        "line": "The multiple-use temperature limit is 922 K. TPSX lists the single-use limit as 1090 K, and both values trace to a Boeing Shuttle data book.",
        "benchmark": "multiple_use_temperature_limit",
        "scope": "material",
        "value": "922 K"
      },
      {
        "label": "Emissivity",
        "line": "The emissivity is 0.87 for the C-9 coated blanket with Astroquartz outer fabric. The record gives no uncoated value.",
        "benchmark": "emissivity",
        "scope": "material",
        "value": "0.87"
      },
      {
        "label": "Thickness",
        "line": "The nominal thickness is 1.0 inch, with a demonstrated range from 0.24 to 1.94 inch, per TPSX footnote 1.",
        "benchmark": "thickness",
        "scope": "material",
        "value": "0.24 to 1.94 inch"
      },
      {
        "label": "Replacement",
        "line": "TPSX predicts that 0.018 of the blanket is replaced per flight, based on Shuttle experience. The record warns that this may vary drastically in another environment.",
        "benchmark": "replacement_fraction_per_flight",
        "scope": "material",
        "value": "0.018 per flight"
      }
    ],
    "compare": "AFRSI is a flexible blanket, so it is set against tile thermal protection only on the points the TPSX record states. The record says AFRSI costs less to install than tile but tolerates high or fluctuating aerodynamic loads less well. Its through-thickness conductivity is 0.0329 W/m-K and its multiple-use limit is 922 K. The AFRSI-2500 variant is a separate grade with its own record and is not compared here.",
    "compare_rows": [
      {
        "label": "Emissivity of the coated blanket",
        "benchmark": "emissivity",
        "scope": "material"
      },
      {
        "label": "Conductivity through the thickness",
        "benchmark": "thermal_conductivity",
        "scope": "material"
      },
      {
        "label": "Multiple-use temperature limit",
        "benchmark": "multiple_use_temperature_limit",
        "scope": "material"
      }
    ],
    "handling": [
      "Keep the blanket below its multiple-use limit of 922 K. TPSX gives the single-use limit as 1090 K.",
      "Plan for inspection and repair of 37200 s/m^2 per flight. TPSX calls this a prediction that may vary by environment.",
      "Control dust from loose silica fibre. The amorphous silica PubChem entry lists H335, which is respiratory irritation."
    ],
    "good_for": [
      "Lower installed cost than tile thermal protection, according to TPSX.",
      "Surfaces without high or fluctuating aerodynamic loads, which is where the Shuttle used it on many leeside surfaces."
    ],
    "watch_out": [
      "Brittleness after thermal exposure, per the TPSX description.",
      "Less suitable than tile for high or fluctuating aerodynamic loads, per TPSX.",
      "Cost and maintenance figures are predicted from Shuttle experience and may vary drastically elsewhere.",
      "AFRSI-2500, an alumina variant with its own TPSX record, is a different grade and is not covered here."
    ],
    "verdict": "AFRSI is a reusable flexible blanket with a lower installed cost than tile thermal protection, used on many Shuttle leeside surfaces. Its limits are brittleness after thermal exposure and weak tolerance of high or fluctuating aerodynamic loads.",
    "recipe": {
      "line": "AFRSI is a sewn, quilted blanket. Its outer fabric is woven silica (Astroquartz), its core is fibrous silica batting (Q-felt), and its inner fabric is woven S-glass. Astroquartz thread stitches the three layers together. The record gives no atomic or mass shares for these constituents.",
      "parts": [
        {
          "name": "Astroquartz outer fabric",
          "role": "Woven silica skin on the hot side. It carries the blanket's emissive coating, which the TPSX values are measured on."
        },
        {
          "name": "Q-felt batting",
          "role": "Fibrous silica insulating core. Its density and thickness set the blanket's areal weight, per TPSX footnote 2."
        },
        {
          "name": "S-glass inner fabric",
          "role": "Woven glass liner on the structure side of the blanket."
        },
        {
          "name": "Astroquartz thread",
          "role": "Stitching that holds the quilted layers together."
        }
      ]
    },
    "risk_groups": [
      {
        "title": "For people",
        "lead": "The chemical behind silica fibre is not classified by most PubChem reporters. One related amorphous silica entry does carry irritant codes, so the dust should be controlled.",
        "points": [
          {
            "label": "The silica record",
            "line": "PubChem's silica summary lists the compound as not classified. 7724 of 9127 company reports say it does not meet GHS hazard criteria."
          },
          {
            "label": "Amorphous silica",
            "line": "A separate amorphous silica entry lists H315 (skin irritation), H319 (serious eye irritation) and H335 (respiratory irritation). The AFRSI fibre form is not stated in that record."
          }
        ],
        "level": 0,
        "verdict": "Not classified as hazardous in the silica record"
      },
      {
        "title": "If the blanket is over-stressed",
        "lead": "TPSX describes two limits: brittleness after heat exposure and poor tolerance of high or fluctuating aerodynamic loads. It gives no failure figure for either.",
        "points": [
          {
            "label": "Brittleness",
            "line": "The TPSX description says the blanket becomes brittle after thermal exposure."
          },
          {
            "label": "Aerodynamic loads",
            "line": "TPSX says AFRSI is less suitable than tile thermal protection for high or fluctuating aerodynamic loads."
          }
        ]
      }
    ]
  },
  "updated": "2026-11-01",
  "review": {
    "status": "draft",
    "method": "assistant",
    "checked_values": 5,
    "unreachable": 0,
    "caveats": 2,
    "note": "Written by an AI assistant on 2026-11-01 from the TPSX AFRSI record (id 12), the NASA TM 101071 PDF, the Wikipedia Space Shuttle TPS article and the PubChem silica record, all fetched in this run. TPSX values are copied as printed with units."
  },
  "sources": {
    "tpsx-afrsi": {
      "title": "NASA Ames TPSX material record: AFRSI Blanket (Material id 12)",
      "id": "TPSX Material id=12; record last modified 2001-10-01; property table last modified 2006-01-05",
      "url": "https://tpsx.arc.nasa.gov/Material?id=12",
      "year": 2006,
      "kind": "database",
      "license": "public domain (NASA)"
    },
    "tpsx-afrsi-2500": {
      "title": "NASA Ames TPSX material record: AFRSI-2500 Blanket (Material id 14)",
      "id": "TPSX Material id=14; separate grade, consulted to confirm the variant is not this grade",
      "url": "https://tpsx.arc.nasa.gov/Material?id=14",
      "year": 2006,
      "kind": "database",
      "license": "public domain (NASA)"
    },
    "ntrs-tm-101071": {
      "title": "Composite Multilayer Insulations for Thermal Protection of Aerospace Vehicles (D. A. Kourtides and W. C. Pitts)",
      "id": "NASA TM 101071 (NTRS 19900000867), February 1989",
      "url": "https://ntrs.nasa.gov/api/citations/19900000867/downloads/19900000867.pdf",
      "year": 1989,
      "kind": "report",
      "license": "public domain (NASA)"
    },
    "wiki-sts-tps": {
      "title": "Wikipedia: Space Shuttle thermal protection system",
      "id": "Wikipedia article, Non-tile TPS section (history and use only)",
      "url": "https://en.wikipedia.org/wiki/Space_Shuttle_thermal_protection_system",
      "year": 2026,
      "kind": "web",
      "license": "CC BY-SA 4.0 (text cited, not reproduced)"
    },
    "pubchem-silica": {
      "title": "PubChem compound record, Silica (CID 24261), GHS classification",
      "id": "CID 24261 (silicon dioxide, EC 231-545-4); amorphous silica entry EC 601-216-3",
      "url": "https://pubchem.ncbi.nlm.nih.gov/compound/24261",
      "year": 2026,
      "kind": "database",
      "license": "public domain (NCBI)"
    }
  },
  "license": "public domain (NASA TPSX and NTRS); CC BY-SA 4.0 Wikipedia text cited only",
  "url": "https://spacemushroom.com/profiles/afrsi-blanket/"
}