AD 97-22-16

This amendment adopts a new airworthiness directive (AD) that applies to certain Raytheon Aircraft Company (Raytheon) Models 1900, 1900C, and 1900D airplanes (formerly referred to as Beech Models 1900, 1900C, and 1900D airplanes). This AD requires fabricating and installing a placard that restricts the use of the forward and aft vent blower assemblies to only the "OFF" or "HIGH" position. This AD also requires incorporating a modification that would replace the bearings on the vent blower assemblies with improved design bearings, and provide thermal protection for the vent blowers, as applicable. Incorporating the modification will eliminate the need for the placard. The AD results from reports of vent blower assembly bearings seizing and locking the blower motor on several of the affected airplanes. The actions specified by this AD are intended to prevent the vent blower assembly bearings from seizing, which could result in smoke emanating from the insulating material covering the electrical wiring and entering the airplane cabin.

Final rule

97-22-16 RAYTHEON AIRCRAFT COMPANY (formerly Beech Aircraft Corporation): Amendment 39-10187; Docket No. 97-CE-11-AD.

Applicability: The following model and serial number airplanes, certificated in any category, that are equipped with either part number (P/N) 114-380028-1 vent blower assemblies or P/N 114-380028-3 vent blower assemblies:

Model
Serial Numbers
1900
UA-2 and UA-3
1900C
UB-1 through UB-74, and UC-1 through UC-174
1900C (C-12J)
UD-1 through UD-6
1900D
UE-1 through UE-244

NOTE 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (f) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Compliance: Required as indicated in the body of this AD, unless already accomplished.

To prevent the vent blower assembly bearings from seizing, which could result in smoke emanating from the insulating material covering the electrical wiring and entering the airplane cabin, accomplish the following:

(a) Within the next 100 hours time-in-service (TIS) after the effective date of this AD, accomplish the following:

(1) Fabricate a placard, using letters at least 1/8-inch in height, with the words: "Operate vent blowers in HIGH or OFF position only".

(2) Install this placard near the vent blower control switch within the pilot's clear view.

(3) This placard requirement may be terminated when the modifications required by paragraph (b) of this AD are incorporated.

(b) Upon accumulating 2,000 total hours TIS or within the next 1,000 hours TIS after the effective date of this AD, whichever occurs later, incorporate one of the following kits, as applicable, in accordance with the referenced kit instructions, as specified in Raytheon Service Bulletin No. 2721, Issued: January 1997:

(1) For P/N 114-380028-1 vent blower assemblies: Electromech Technologies Kit No. EM630-201-1 or EM630-201-2 (as appropriate for the blower serial number), in accordance with the Update Procedures for the Electromech Technologies EM630 Blower (Raytheon P/N 114- 380028-1 for Installation of Kit P/N's 630-201-1 and 630-201-2), dated December 9, 1996. These kits, when incorporated, replace the bearings on the vent blower assemblies with improved design bearings, and provide thermal protection for the vent blowers; or

(2) For P/N 114-380028-3: Advanced Industries Kit No. BC80A905 in accordance with Advanced Industries, Inc. Installation Procedure for the Resistor Wiring Harness Kit on the BC80A-1 Blower, dated October 9, 1996. This kit, when incorporated, provides thermal protection for the vent blowers.

(c) As of the effective date of this AD, no person may install P/N 114-380028-1 or P/N 114-380028-3 vent blower assemblies without first incorporating the appropriate kit(s), as referenced in paragraphs (b)(1) and (b)(2) of this AD.

(d) Fabricating and installing the placard as required by paragraphs (a)(1) and (a)(2) of this AD may be performed by the owner/operator holding at least a private pilot certificate as authorized by section 43.7 of the Federal Aviation Regulations (14 CFR 43.7), and must be entered into the aircraft records showing compliance with this AD in accordance with section 43.11 of the Federal Aviation Regulations (14 CFR 43.11).

(e) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished.

(f) An alternative method of compliance or adjustment of the compliance time that provides an equivalent level of safety may be approved by the Manager, Wichita Aircraft Certification Office (ACO), 1801 Airport Road, Room 100, Mid-Continent Airport, Wichita, Kansas 67209. The request shall be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Wichita ACO.

NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Wichita ACO.

(g) The modification required by this AD shall be done in accordance with the Update Procedures for the Electromech Technologies EM630 Blower (Raytheon P/N 114-380028-1 for Installation of Kit P/N's 630-201-1 and 630-201-2), dated December 9, 1996; and Advanced Industries, Inc. Installation Procedure for the Resistor Wiring Harness Kit on the BC80A-1 Blower, dated October 9, 1996. Both of these documents are referenced in Raytheon Service Bulletin No. 2721, Issued: January, 1997. 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 the Raytheon Aircraft Company, P.O. Box 85, Wichita, Kansas 67201-0085. Copies may be inspected at the FAA, Central Region, Office of the Regional Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri, or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

(h) This amendment becomes effective on December 5, 1997.

Events Leading to the Issuance of This AD

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an AD that would apply to certain Raytheon Models 1900, 1900C, and 1900D airplanes was published in the Federal Register as a notice of proposed rulemaking (NPRM) on May 29, 1997 (62 FR 29086). The NPRM proposed to require (1) fabricating and installing a placard that restricts the use of the vent blower assemblies; and (2) incorporating a modification that would replace the bearings in the vent blower assemblies with improved design bearings, and provide thermal protection for the vent blowers, as applicable. Incorporating the modification would eliminate the need for the placard. Accomplishment of the proposed modification as specified in the NPRM would be in accordance with the Update Procedures for the Electromech Technologies EM630 Blower (Raytheon P/N 114-380028-1 for Installation of Kit P/N's 630-201-1 and 630-201-2), dated December 9, 1996; and Advanced Industries, Inc. Installation Procedure for the Resistor Wiring Harness Kit on the BC80A-1 Blower, dated October 9, 1996. Both of these documents are referenced in Raytheon Service Bulletin No. 2721, Issued: January 1997.

The NPRM resulted from vent blower assembly bearings seizing and locking the blower motor on several of the affected airplanes.

Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were received on the proposed AD or on the FAA's determination of the cost to the public.

The FAA's Determination
After careful review of all available information related to the subject presented above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed except for minor editorial corrections. The FAA has determined that these minor corrections will not change the meaning of the AD and will not add any additional burden upon the public than was already proposed.

Cost Impact
The FAA estimates that 500 airplanes in the U.S. registry will be affected by this AD, that it will take approximately 7 workhours per airplane to accomplish the required modification, and that the average labor rate is approximately $60 an hour. Parts cost approximately $500 per airplane. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $460,000. These figures are based on the presumption that no owner/operator of the affected airplanes has incorporated the modification.

Raytheon has informed the FAA that approximately 700 kits have been shipped from the Raytheon Aircraft Authorized Service Center. This is enough to equip 350 of the affected airplanes (two vent blower assemblies per airplane). Presuming that each of the 350 sets of kits is incorporated on an affected airplane, the cost impact of this AD is reduced by $322,000 from $460,000 to $138,000.

Regulatory Impact
The regulations adopted herein will not have substantial direct effects on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. Therefore, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.

For the reasons discussed above, I certify that this action (1) is not a "significant regulatory action" under Executive Order 12866; (2) is not a "significant rule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. A copy of the final evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption "ADDRESSES".

List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.

Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:

PART 39 - AIRWORTHINESS DIRECTIVES
1. The authority citation for part 39 continues to read as follows:
Authority: 49 USC 106(g), 40113, 44701.

39.13 [Amended]
2. Section 39.13 is amended by adding a new airworthiness directive (AD) to read as follows: