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How to Spec Nacelle Insulation: What to Send H-O for a Quote
Propulsion-zone insulation attracts underspecified quote requests because the geometry looks like the whole story: a blanket core with a cutout, a duct sleeve, a gasket on a liner. What the quote actually prices is the duty behind the geometry, the section temperatures, the fire role, the fluid at the seal, and the way the part attaches. This is the ten-item checklist the H-O applications team works from, what engineering does with each item, and what comes back.
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The ten things to send, and what each decides
Propulsion-zone insulation attracts underspecified RFQs because the geometry looks like the whole story: a blanket core with a cutout, a duct sleeve, a strip of gasket on a liner. What the quote actually prices is the duty behind the geometry: how hot each section runs, what fire role the part carries, what fluid can reach the seal, how the part attaches, and whether it is a thermal part or a fire part.
This is the ten-item checklist the H-O applications team works from for nacelle cores, duct lagging, fire-barrier plies, sponge seals, and facings, drawn from the parent application page's own engineering-review list, plus what engineering does with each item and what comes back.
| Send this | What it decides |
|---|---|
| 1. The job: thermal core, fire barrier, seal, or facing | The fundamental split. Cores and lagging are judged per ASTM C177; sponge seals per ASTM D1056; fire plies by inorganic temperature capability and the integrator's fire-zone campaign. They are not compared in one column. |
| 2. Zone temperature profile, by section | Continuous soak, transient peak, and radiant load, section by section. SOLIMIDE covers the inlet and cowl regime; aerogel splits warm versus hottest runs; inorganic plies hold what no organic foam should see. |
| 3. The part's fire role and governing framing | FAR 25.856 for thermal-acoustic insulation, FAR 25.853 for interiors, ISO 2685 and AC 20-135 for fire-zone hardware. The role decides which data the material must carry. |
| 4. Fluid exposure at each seal | Dry, mist, or continuous. Dry locations stay on silicone economics; mist and drip paths move to fluorosilicone (AMS 3323); continuous immersion is a different page entirely. |
| 5. Closure force and cycle count at seals | Firmness to the real closure force and compression-set data per ASTM D1056 for high-cycle doors. Set, not day-one firmness, is the life-limiting property. |
| 6. Mass and thickness budget | Nacelle hardware pays for mass twice. SOLIMIDE buys mass margin; aerogel buys thickness margin; the facing protects whichever one you bought. |
| 7. Airflow, vibration, and handling exposure | Facing layout, edge closures, rub strips, and cushion plies. Erosion starts at edges and seams, so the closure detail is part of the spec. |
| 8. Attachment and serviceability | Bonded cores, lace-on wraps, removable APU blankets, and retained fire seals each drive a different converted format and PSA or closure choice. |
| 9. Geometry and ply order: DXF, STEP, or PDF | Footprint, cutouts, loft clearance for aerogel, lamination order for barrier stacks, and tab placement, the items that decide line speed more than the material does. |
| 10. Prototype and production volumes | Converting method and price structure. Every part is made to order; prototype quantities through full ship-set production are equally accepted, and MOQ varies by material and part. |
What engineering does with the list
Items 1 through 3 pick the layer architecture: a SOLIMIDE polyimide core for the inlet and cowl, ArmaGel or Pyrogel XTE lagging split by section temperature, and mica or ManniGlas plies where item 3 names a fire-barrier duty. Items 4 and 5 pick the seals: dry-zone BISCO HT or BF silicone foam and kSil V-0, or fluorosilicone sponge where a fluid reaches the joint. Items 6 and 7 add the PTFE-coated fiberglass facing and edge protection.
Items 8 through 10 become the converting plan and the price structure. The reply cites each recommended grade's TDS values with the method named, and flags anything the checklist left open.
What happens after you send it
- Drawing review. Engineering reviews the stack against the vendor TDS: section temperatures, fire role, fluid exposure, closure force, mass and thickness budget, and attachment method.
- Material direction and quote. A family and grade direction with the TDS attached, the converted format (die-cut core, knife-cut aerogel sleeve, laminated barrier stack, kiss-cut seal), and pricing at your quantities.
- Samples. Typically 3 to 5 business days for common die-cut configurations on materials we keep on hand.
- Production. Standard runs ship about two weeks after drawing approval, including laminated and kitted ship-set configurations; expedited service is available. Ongoing parts run with material traceability and lot-code TDS records.
Documentation available on request: material technical data sheet, certificate of conformance, and lot traceability, under our ISO 9001:2015 certified quality management system. H-O is a die-cut converter, not a raw-material producer: we do not manufacture the raw foam, blanket, paper, or sponge, we do not independently certify them, and fire-zone qualification, FAR 25.856 compliance, and airworthiness sign-off belong to the airframer and the propulsion integrator.
The mistakes this checklist prevents
| Spec mistake | What it causes | Checklist item that catches it |
|---|---|---|
| One grade across the whole bleed system | Lagging embrittles on the hottest section | Item 2, section-by-section temperatures |
| Silicone seal in the oil-mist path | Swelling, softening, a weeping panel | Item 4, fluid exposure named |
| Fire seal chosen on day-one firmness | Lost sealing force after a couple of years | Item 5, compression set per ASTM D1056 |
| Facing without an edge-closure detail | Airflow erodes the seam to fibers | Item 7, closure and airflow direction |
| Interior fire data on a fire-zone part | Wrong framing for the part's actual role | Item 3, fire role and standard named |
| Aerogel cut tight and forced into place | Compressed blanket above its rated conductivity | Items 9 and 6, loft clearance specified |
Frequently asked questions
What information do I need to send H-O to quote a nacelle insulation part?
Ten items turn the geometry into a quotable drawing: the job (thermal core, fire barrier, seal, or facing), the zone temperature profile by section, the part's fire role and governing framing, the fluid exposure at each seal, the closure force and cycle count, the mass and thickness budget, the airflow and handling exposure, the attachment method, the geometry and ply order as DXF, STEP, or PDF, and the prototype and production volumes. Send what you have; engineering frames the rest and flags any assumption.
Can H-O cross-reference the material grade or AMS designation on my print?
In most cases, yes. If your drawing calls out a nacelle core, aerogel lagging, mica or glass-fiber ply, or a silicone or fluorosilicone seal by a brand part number or an AMS or MIL designation, engineering identifies a comparable grade from the lines we convert, matching on temperature position per ASTM C177, set behavior per ASTM D1056, fluid resistance, and the fire framing the part's role requires. It is an industry cross-reference, not a guaranteed drop-in, verified against the vendor TDS before quoting.
How should aerogel parts be specified so they install correctly?
Specify the installed condition, not just the material: cut geometry with clearance for blanket loft, fastening or wrapping that locates without crushing, and facings or edge treatment where airflow erosion or handling is real. Steady-state conductivity is measured uncompressed per ASTM C177, so a sleeve forced flat performs above the number the design was sold on. H-O knife-cuts aerogel into fitted sleeves, saddles, and flange collars to geometry that installs the way the TDS was tested.
Does H-O supply complete nacelle insulation kits?
Yes. The deliverable that makes ship-set installation repeatable is the kit: every core, ply, facing, gasket, and rub strip die-cut to drawing, labeled, and packed in installation order, with lot-coded material traceability behind each part. H-O die-cuts, knife-cuts, kiss-cuts on liner, slits, laminates multi-layer stacks, and kits across all the families on the parent page as an ISO 9001:2015 certified organization in Winsted, Connecticut.
What lead time should I expect for samples and production?
Every nacelle part is made to order, including samples. Samples typically ship in 3 to 5 business days for common die-cut configurations on materials we keep on hand; standard production runs ship about two weeks after drawing approval, including laminated and kitted ship-set configurations; expedited service is available when timing is critical. MOQ varies by material and part, and prototype quantities through full production are equally accepted.
Send the checklist, get a nacelle insulation quote
Attach the geometry and as many of the ten items as you have. If something is unknown, say so; the review proceeds with the assumption flagged.
Samples typically ship in 3 to 5 business days for common die-cut configurations on materials we keep on hand; standard production runs about two weeks after drawing approval; expedited service is available. MOQ varies by material and part.
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Related reading
Request a quote for your engine-bay & nacelle thermal insulation part
Send H-O your drawing or describe the part—engineering reviews every RFQ and converts samples on your geometry.
Last updated · Reviewed by H-O Products engineering (ISO 9001:2015 certified converter, Winsted, CT).
References
- ASTM C177 (steady-state thermal conductivity, the core and lagging comparison basis); ASTM D1056 (compression-deflection and set for sponge seals).
- FAR 25.856 (thermal-acoustic insulation framing); FAR 25.853 (interiors); ISO 2685 and AC 20-135 (fire-zone hardware, owned by the integrator).
- AMS 3323 (fluorosilicone sponge); UL 94 and ASTM E162 / E662 (flame, smoke, and toxicity data, per grade).
- Manufacturer technical data sheets for the polyimide foam, aerogel blanket, mica, glass-fiber paper, silicone and fluorosilicone sponge, and PTFE-coated fiberglass grades named on the parent application page.
This article summarizes specification principles for a quotation workflow for engine-bay and nacelle insulation using the families and published test methods cited on the parent application page. Comparisons are qualitative; per-grade values quoted are maker-TDS figures and must be confirmed on the manufacturer's current technical data sheet at your thickness, temperature, and installed condition. Standards (FAR, AMS, ISO, ASTM, UL) are cited by designation for context, not as a claim of qualification.
H-O is a precision die-cut converter, not a raw-material producer, and does not perform thermal design, certify materials, or hold flight or fire-zone qualification; those belong to the airframer, the propulsion integrator, and their test houses.