[Federal Register Volume 59, Number 61 (Wednesday, March 30, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-7496]


[[Page Unknown]]

[Federal Register: March 30, 1994]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 93-CE-03-AD]

 

Airworthiness Directives: Fairchild Aircraft SA26, SA226, and 
SA227 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes to revise AD 93-19-06, which currently 
requires repetitively inspecting acrylic cabin and cockpit windows for 
cracks on certain Fairchild Aircraft SA26, SA226, and SA227 series 
airplanes, and, if cracks are found that exceed certain limits, 
replacing that window. The proposed action would more fully define the 
crack limits and establish clearer repetitive inspection intervals 
under those crack limits for the affected airplanes. The actions 
specified by the proposed AD are intended to prevent acrylic cockpit or 
cabin window failures, which could result in airframe damage and 
decompression injuries.

DATES: Comments must be received on or before June 10, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Central Region, Office of the Assistant Chief 
Counsel, Attention: Rules Docket No. 93-CE-03-AD, Room 1558, 601 E. 
12th Street, Kansas City, Missouri 64106. Comments may be inspected at 
this location between 8 a.m. and 4 p.m., Monday through Friday, 
holidays excepted.
    Service information that applies to the proposed AD may be obtained 
from Fairchild Aircraft, P.O. Box 790490, San Antonio, Texas 78279-
0490; telephone (210) 824-9421. This information also may be examined 
at the Rules Docket at the address above.

FOR FURTHER INFORMATION CONTACT: Mr. Hung Viet Nguyen, Aerospace 
Engineer, FAA, Airplane Certification Office, 2601 Meacham Boulevard, 
Fort Worth, Texas 76137-0150; telephone (817) 222-5150; facsimile (817) 
222-5959.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed rule by submitting such written data, views, or arguments as 
they may desire. Communications should identify the Rules Docket number 
and be submitted in triplicate to the address specified above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this notice may be changed in 
light of the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed rule. All 
comments submitted will be available, both before and after the closing 
date for comments, in the Rules Docket for examination by interested 
persons. A report that summarizes each FAA-public contact concerned 
with the substance of this proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket No. 93-CE-03-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Central Region, Office of the Assistant Chief Counsel, 
Attention: Rules Docket No. 93-CE-03-AD, Room 1558, 601 E. 12th Street, 
Kansas City, Missouri 64106.

Discussion

    AD 93-19-06, Amendment 39-8705 (58 FR 51771, October 5, 1993), 
currently requires repetitively inspecting acrylic cabin and cockpit 
windows for cracks on certain Fairchild Aircraft SA26, SA226, and SA227 
series airplanes, and, if cracks are found that exceed certain limits, 
replacing that window. The actions are accomplished in accordance with 
the following service bulletins (SB), as applicable:

Fairchild SB 226-56-001, Issued: February 2, 1983; Revised: November 
26, 1991.
Fairchild SB 227-56-001, Issued: February 2, 1983; Revised: November 
26, 1991.
Fairchild SB 226-56-002, Issued: March 3, 1983; Revised: May 29, 
1992.
Fairchild SB 227-56-002, Issued: January 5, 1984; Revised: May 29, 
1992, and April 1, 1993.
Fairchild SB 226-56-003, Issued: September 13, 1984; Revised: 
November 2, 1989.
Fairchild SB 227-56-003, Issued: September 13, 1984; Revised: 
November 2, 1989.
Fairchild SB 26-56-10-038, Issued: October 8, 1984; Revised: 
February 7, 1991.
Fairchild SB 26-56-20-042, Issued: November 28, 1988; Revised: 
February 7, 1991.

    Since issuance of that AD and after examining the circumstances and 
reviewing all available information related to the action referenced 
above, the FAA has determined that (1) the crack limits specified in AD 
93-19-06 should coincide with the applicable service information to 
more fully establish either replacement or repetitive inspection 
interval requirements; and (2) AD action should be taken to continue to 
prevent acrylic cockpit or cabin window failures, which could result in 
airframe damage and decompression injuries.
    Since an unsafe condition has been identified that is likely to 
exist or develop in other Fairchild Aircraft SA26, SA226, and SA227 
series airplanes of the same type design, the proposed AD would revise 
AD 93-19-06 to more fully define the crack limits and establish clearer 
repetitive inspection intervals under those crack limits for the 
affected airplanes. The proposed action would continue to be 
accomplished in accordance with the previously referenced service 
information.
    The compliance time for the proposed AD is presented in both hours 
time-in-service (TIS) and calendar time. The referenced acrylic cabin 
and cockpit windows are affected by those conditions present while the 
airplane is in flight and while the airplane is on the ground. In 
addition, the utilization rates of the affected airplanes vary among 
operators. For example, operators in unscheduled service utilize their 
airplanes an average of approximately 300 to 400 hours TIS annually, 
while those in commuter service (scheduled) utilize their airplanes an 
average of approximately 2,000 hours TIS annually. Based on this wide 
utilization rate variance and the fact that these windows are affected 
when the airplane is in flight and on the ground, the FAA has 
determined that the affected acrylic cabin and cockpit windows should 
be repetitively inspected every 1,000 hours TIS, or every 12 calendar 
months, whichever occurs first.
    The FAA estimates that 633 airplanes in the U.S. registry would be 
affected by the proposed AD, that it would take approximately 3 
workhours per airplane to accomplish the proposed action, and that the 
average labor rate is approximately $55 an hour. Based on these 
figures, the total cost impact of the proposed AD on U.S. operators is 
estimated to be $104,445. AD 93-19-06 currently requires the same 
inspections as the proposed AD for all of the affected airplanes. 
Therefore, the cost impact of the proposed AD on U.S. operators of all 
affected airplanes is the same as AD 93-19-06.
    The regulations proposed herein would 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 
proposal would 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) if promulgated, 
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 draft regulatory evaluation 
prepared for this action has been placed 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, Safety.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 14 
CFR part 39 of the Federal Aviation Regulations as follows:

PART 39--AIRWORTHINESS DIRECTIVES

    1. The authority citation for part 39 continues to read as follows:

    Authority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C. 
106(g); and 14 CFR 11.89.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing AD 93-19-06, Amendment 39-
8705 (58 FR 51771, October 5, 1993), and by adding the following new 
airworthiness directive to read as follows:

Fairchild Aircraft: Docket No. 93-CE-03-AD. Revises AD 93-19-06, 
Amendment 39-8705.

    Applicability: Models SA26-T, SA26-AT, SA226-T, SA226-T(B), 
SA226-AT, SA226-TC, SA227-AT, SA227-AC, and SA227-TT airplanes (all 
serial numbers for all models), certificated in any category.

    Note 1: The applicability of this AD takes precedence over that 
specified in the service information.

    Compliance: Required initially within the next 50 hours time-in-
service (TIS) after the effective date of this AD, unless already 
accomplished within the last 1,000 hours TIS or 12 calendar months 
(compliance with AD 89-06-02 or AD 93-19-06), and thereafter as 
indicated in the body of this AD.
    To prevent acrylic cockpit or cabin window failures, which could 
result in airframe damage and decompression injuries, accomplish the 
following:

    Note 2: The paragraph structure of this AD is as follows:
    Level 1: (a), (b), (c), etc.
    Level 2: (1), (2), (3), etc.
    Level 3: (i), (ii), (iii), etc.
    Level 2 and Level 3 structures are designations of the Level 1 
paragraph they immediately follow.
    (a) Visually inspect all acrylic cabin side windows and all 
acrylic cockpit windows for cracks in accordance with the following 
service bulletins (SB), as applicable:
    (1) For acrylic cabin side windows: 

------------------------------------------------------------------------
     Model                           Service bulletin                   
------------------------------------------------------------------------
SA26-T..........  26-56-20-042, Issued: November 28, 1988, Revised:     
                   November 26, 1991.                                   
SA26-AT.........  26-56-20-042, Issued: November 28, 1988, Revised:     
                   November 26, 1991.                                   
SA226-T.........  226-56-001, Issued: February 2, 1983, Revised:        
                   February 7, 1991.                                    
SA226-T(B)......  226-56-001, Issued: February 2, 1983, Revised:        
                   February 7, 1991.                                    
SA226-AT........  226-56-002, Issued: March 3, 1983, Revised: May 29,   
                   1992.                                                
SA226-TC........  226-56-002, Issued: March 3, 1983, Revised: May 29,   
                   1992.                                                
SA227-AT........  227-56-002, Issued: January 5, 1984, Revised: May 29, 
                   1992, and April 1, 1993.                             
SA227-AC........  227-56-002, Issued January 5, 1984, Revised: May 29,  
                   1992, and April 1, 1993.                             
SA227-TT........  227-56-001, Issued February 2, 1983, Revised: November
                   26, 1991.                                            
------------------------------------------------------------------------

    (2) For acrylic cockpit windows: 

------------------------------------------------------------------------
     Model                           Service Bulletin                   
------------------------------------------------------------------------
SA26-T..........  26-56-10-038, Issued: October 8, 1984, Revised:       
                   February 7, 1991.                                    
SA26-AT.........  26-56-10-038, Issued: October 8, 1984, Revised:       
                   February 7, 1991.                                    
SA226-T.........  226-56-003, Issued: September 13, 1984, Revised:      
                   November 2, 1989.                                    
SA226-T(B)......  226-56-003, Issued: September 13, 1984, Revised:      
                   November 2, 1989.                                    
SA226-AT........  226-56-003, Issued: September 13, 1984, Revised:      
                   November 2, 1989.                                    
SA226-TC........  226-56-003, Issued: September 13, 1984, Revised:      
                   November 2, 1989.                                    
SA227-AT........  227-56-003, Issued: September 13, 1984, Revised:      
                   November 2, 1989.                                    
SA227-AC........  227-56-003, Issued: September 13, 1984, Revised:      
                   November 2, 1989.                                    
SA227-TT........  227-56-003, Issued: September 13, 1984, Revised:      
                   November 2, 1989.                                    
------------------------------------------------------------------------

    (b) If cracks are found that meet or exceed 4.3 inches in 
combined length, prior to further flight, replace the window with a 
new or serviceable window, and reinspect thereafter at intervals not 
to exceed 1,000 hours TIS or 12 calendar months, whichever occurs 
first.
    (c) If cracks are found that are less than 4.3 inches in 
combined length but that meet or exceed .30 inch as specified in the 
Crack Limits section of the service information referenced in 
paragraphs (a)(1) and (a)(2) of this AD, prior to further flight, 
accomplish one of the following:
    (1) Replace the window with a new or serviceable window and 
reinspect thereafter at intervals not to exceed 1,000 hours TIS or 
12 calendar months, whichever occurs first; or
    (2) Fabricate a placard with the following words in letters at 
least 0.10-inch in height and install this placard within the 
pilot's clear view close to the pressurization controls: ``AIRPLANE 
MUST BE OPERATED UNPRESSURIZED'', and accomplish both of the 
following:
    (i) Insert a copy of this AD into the Limitations Section of the 
FAA-approved Airplane Flight Manual (AFM); and
    (ii) Within the next 25 hours TIS or 30 calendar days, whichever 
occurs first, reinspect the cracked window for crack progression in 
accordance with the inspections specified in paragraph (a) of this 
AD, as applicable, and accomplish either paragraph (b), (c) or (d) 
of this AD, as applicable.
    (d) If cracks are found that are less than .30 inches as 
specified in the Crack Limits section of the applicable service 
information referenced in paragraphs (a)(1) and (a)(2) of this AD, 
within the next 25 hours TIS or 30 calendar days, whichever occurs 
first, reinspect the cracked window for crack progression in 
accordance with the applicable service information specified in 
paragraphs (a)(1) and (a)(2) of this AD, and accomplish either 
paragraph (b), (c), or (d) of this AD, as applicable.

    Note 3: The repetitive inspections required by this AD are also 
referenced in the FAA-approved Fairchild Airframe Airworthiness 
Limitations Manual, ST-UN-M001.

    (e) Special flight permits may be issued in accordance with 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 
initial or repetitive compliance times that provides an equivalent 
level of safety may be approved by the Manager, Airplane 
Certification Office, FAA, 2601 Meacham Boulevard, Fort Worth, Texas 
76137. The request shall be forwarded through an appropriate FAA 
Maintenance Inspector, who may add comments and then send it to the 
Manager, Fort Worth Airplane Certification Office.

    Note 4: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Fort Worth Airplane Certification Office.

    (g) This amendment revises AD 93-19-06, Amendment 39-8705.

    Issued in Kansas City, Missouri, on March 24, 1994.
Bobby W. Sexton,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-7496 Filed 3-29-94; 8:45 am]
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