REGULATION — LEGALLY BINDING

§ 91.613 Materials for compartment interiors

14 CFR Part 91 — Subpart G—Additional Equipment and Operating Requirements for Large and Transport Category Aircraft

Official text — 14 CFR § 91.613

REGULATION — LEGALLY BINDING

(a) No person may operate an airplane that conforms to an amended or supplemental type certificate issued in accordance with SFAR No. 41 for a maximum certificated takeoff weight in excess of 12,500 pounds unless within 1 year after issuance of the initial airworthiness certificate under that SFAR the airplane meets the compartment interior requirements set forth in § 25.853 (a), (b), (b-1), (b-2), and (b-3) of this chapter in effect on September 26, 1978.

(b) Thermal/acoustic insulation materials. For transport category airplanes type certificated after January 1, 1958:

(1) For airplanes manufactured before September 2, 2005, when thermal/acoustic insulation is installed in the fuselage as replacements after September 2, 2005, the insulation must meet the flame propagation requirements of § 25.856 of this chapter, effective September 2, 2003, if it is:

(i) Of a blanket construction or

(ii) Installed around air ducting.

(2) For airplanes manufactured after September 2, 2005, thermal/acoustic insulation materials installed in the fuselage must meet the flame propagation requirements of § 25.856 of this chapter, effective September 2, 2003.

Reproduced from the eCFR. Text as amended through 2026-07-31. Verify against the official source before relying on it operationally.

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Text published in the Code of Federal Regulations. Regulations are legally binding on pilots and operators.

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