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93-23-01: Water Heaters and Coffee Makers

FAA order 93-23-01 is an airworthiness directive in force since December 7, 1993. The FAA's subject line: Water Heaters and Coffee Makers. It names Airbus A300, Airbus A320, Boeing Of Canada/Dehav Div DHC-8, Boeing 727, Boeing 737, Boeing 747, Boeing 757, Boeing 767, Bombardier CL-600 Challenger and CRJ, Bombardier DHC-8 Dash 8 and Q400, Dassault MYSTERE-FALCON 50, Dassault MYSTERE FALCON 900, Dehavilland DHC-8, Douglas DC-10, Douglas DC-9, Gulfstream American Corp G-1159, Gulfstream G-IV Gulfstream IV, Mcdonnell Douglas DC-10, Mcdonnell Douglas DC-9, Mcdonnell Douglas MD-11: about 7,643 aircraft on the U.S. register today across them, though an order usually covers particular versions or serial numbers rather than every one. System: other and general.

What it applies to as the FAA lists it

Kind of product
Appliance
Makes
Airbus; The Boeing Company; Bombardier Inc.; Dassault Aviation; Fokker Services; Gulfstream Aerospace Corporation; Nordskog Industries, Inc.
Models
A300 B2-1A, A300 B2-1C, A300 B2-203, A300 B2K-3C, A300 B4-103, A300 B4-203, A300 B4-2C, A300 B4-601, A300 B4-603, A300 B4-605R, A300 B4-620, A300 B4-622, A300 B4-622R, A300 C4-605R Variant F, A300 F4-605R, A300 F4-622R, A310-203, A310-204, A310-221, A310-222, A310-304, A310-322, A310-324, A310-325, A320-111, A320-211, A320-212, A320-214, A320-231, A320-232, A320-233, 727-100 Series, 727-100C Series, 727-200 Series, 727-200F Series, 727 Series, 727C Series, 737-100 Series, 737-200 Series, 737-200C Series, 737-300 Series, 737-400 Series, 737-500 Series, 747-100 Series, 747-100B Series,...
On this site
Airbus A300 120 registered
Airbus A320 792 registered
Boeing Of Canada/Dehav Div DHC-8 6 registered
Boeing 727 37 registered
Boeing 737 2,896 registered
Boeing 747 192 registered
Boeing 757 440 registered
Boeing 767 585 registered
Bombardier CL-600 Challenger and CRJ 1,655 registered
Bombardier DHC-8 Dash 8 and Q400 58 registered
Dassault MYSTERE-FALCON 50 90 registered
Dassault MYSTERE FALCON 900 129 registered
Dehavilland DHC-8 28 registered
Douglas DC-10 8 registered
Douglas DC-9 7 registered
Gulfstream American Corp G-1159 29 registered
Gulfstream G-IV Gulfstream IV 357 registered
Mcdonnell Douglas DC-10 17 registered
Mcdonnell Douglas DC-9 93 registered
Mcdonnell Douglas MD-11 104 registered

Dates and paperwork

In force since
December 7, 1993
Docket
93-NM-181-AD
Status
Current
The FAA's document
Read the order on the FAA's site

The order itself the regulatory text, as published

Show the full text (3,691 characters)
93-23-01 NORDSKOG INDUSTRIES, INC.: Amendment 39-8735. Docket 93-NM-181-AD. \n\n\tApplicability: Nordskog water heaters and coffee makers, as listed in Nordskog Industries, Inc., Service Bulletin SB-93-34, dated October 21, 1993; as installed in, but not limited to Boeing Model 727, 737, 747, 757, and 767 series airplanes; McDonnell Douglas Model DC-9, DC-9-80, and DC-10 series airplanes, and MD-11 airplanes; Lockheed Model L-1011 series airplanes; Airbus Industrie Model A300, A310, and A320 series airplanes; Gulfstream Model G-1159 series airplanes and Model G-IV airplanes; de Havilland, Inc., Model DHC-8 series airplanes; Dassault-Aviation Model Mystere-Falcon 50 and 900 series airplanes; Canadair Model CL-600-1A11 (CL-600), CL-600-2A12 (CL-601), and CL-600-2B16 (CL-601-3A and -3R) and CL-600-2B19 series airplanes; and Fokker Model F27 and F28 series airplanes; certificated in any category. \n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tTo preventexplosions of galley water heaters and coffee makers and subsequent injuries to passengers or cabin crew members, accomplish the following: \n\n\t(a)\tWithin 30 days after the effective date of this AD, perform a one-time inspection to determine whether a NUPRO pressure relief valve having part number (P/N) SS-2C4-65 has been installed, in accordance with Nordskog Industries, Inc., Service Bulletin SB-93-34, dated October 21, 1993. If any NUPRO pressure relief valve having P/N SS-2C4-65 has been installed, prior to further flight, accomplish either paragraph (a)(1) or (a)(2) of this AD. \n\n\t\t(1)\tRemove the NUPRO pressure relief valve having P/N SS-2C4-65 and install a new, improved NUPRO pressure relief valve having P/N SS-CHF2-65, in accordance with the service bulletin. Or \n\n\t\t(2)\tDeactivate any Nordskog water heater or coffee maker listed in the service bulletin on which a NUPRO pressure relief valve having P/N SS-2C4-65 has been installed, and install a placard stating, "Not tobe used." \n\n\t(b)\tAs of the effective date of this AD, no person shall install a NUPRO pressure relief valve having P/N SS-2C4-65 on any airplane. \n\n\t(c)\tAn alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Los Angeles ACO. \n\n\tNOTE: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Los Angeles ACO. \n\n\t(d)\tSpecial flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the airplane to a location where the requirements of this AD can be accomplished. \n\n\t(e)\tThe inspection and replacement shall be done in accordance with Nordskog Industries, Inc., Service Bulletin SB-93-34, dated October 21, 1993. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from Nordskog Industries, Inc., 16000 Strathern Street, Van Nuys, California 91406. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Los Angeles ACO, 3229 E. Spring Street, Long Beach, California 90806-2425; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. \n\n\t(f)\tThis amendment becomes effective on December 7, 1993.

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Source: FAA Dynamic Regulatory System, airworthiness directives. The FAA's document is the authority; the register counts are this site's, from the FAA register of November 6, 2026. Connections as data: /graph/directive/93-23-01.json · aircraft systems.