Airworthiness Directives; Schweizer Aircraft Corporation Model 269C-1 Helicopters

[Federal Register Volume 64, Number 30 (Tuesday, February 16, 1999)]
[Rules and Regulations]
[Pages 7493-7494]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-3588]



[[Page 7493]]

-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

RIN 2120-AA64
[Docket No. 98-SW-39-AD; Amendment 39-11038; AD 99-04-14]


Airworthiness Directives; Schweizer Aircraft Corporation Model 
269C-1 Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to Schweizer Aircraft Corporation Model 269C-1 helicopters, 
that requires a visual inspection of the bond line between the main 
rotor blade (blade) abrasion strip (abrasion strip) and the blade for 
voids, separation, or lifting of the abrasion strip; a visual 
inspection of the adhesive bead around the perimeter of the abrasion 
strip for erosion, cracks, or blisters; a tap (ring) test of the 
abrasion strip for debonding or hidden corrosion voids; and removal of 
any blade with an unairworthy abrasion strip and replacement with an 
airworthy blade. This amendment is prompted by four reports that 
indicate that debonding and corrosion have occurred on certain blades 
where the abrasion strip attaches to the blade skin. The actions 
specified by this AD are intended to prevent loss of the abrasion strip 
from the blade and subsequent loss of control of the helicopter.

EFFECTIVE DATE: March 23, 1999.

FOR FURTHER INFORMATION CONTACT: Raymond Reinhardt, Aerospace Engineer, 
FAA, New York Aircraft Certification Office, Airframe and Propulsion 
Branch, Engine and Propeller Directorate, 10 Fifth Street, 3rd Floor, 
Valley Stream, New York 11581-1200, telephone (516) 256-7532, fax (516) 
568-2716.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an AD that is 
applicable to Schweizer Aircraft Corporation and Hughes Helicopters, 
Inc. Model 269C-1 helicopters was published in the Federal Register on 
November 10, 1998 (63 FR 62973). That action proposed to require a 
visual inspection of the bond line between the blade abrasion strip and 
the blade for voids, separation, or lifting of the abrasion strip; a 
visual inspection of the adhesive bead around the perimeter of the 
abrasion strip for erosion, cracks, or blisters; a tap (ring) test of 
the abrasion strip for debonding or hidden corrosion voids; and removal 
of any blade with an unairworthy abrasion strip and replacement with an 
airworthy blade.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received. One commenter states that the references to 
Hughes Helicopters are unnecessary because the helicopter was, in fact, 
designed and certificated by Schweizer Aircraft Corporation. The FAA 
concurs and has removed ``Hughes Helicopters'' from the AD. The same 
commenter states that a serial number listed in the applicability 
paragraph is incorrectly referenced as ``S508'' and that it should be 
``S509.'' The FAA does not concur because the number is correctly 
referenced as ``S509.'' Additionally, in the terminating action 
paragraph (d) ``repair'' has been replaced with ``rebonding'' to more 
specifically state what repair constitutes terminating action.
    After careful review of the available data, including the comments 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule with the changes described 
previously. The FAA has determined that these changes will neither 
increase the economic burden on any operator nor increase the scope of 
the AD.
    The FAA estimates that 47 helicopters of U.S. registry will be 
affected by this AD, that it will take approximately one-third of a 
work hour per helicopter to conduct the initial inspections; 
approximately one-third of a work hour to conduct the repetitive 
inspections; approximately 11 work hours to remove and reinstall a 
blade; and approximately 32 work hours to repair the blade; and that 
the average labor rate is $60 per work hour. Required parts 
(replacement abrasion strips) will cost approximately $57 per main 
rotor abrasion strip (each helicopter has three main rotor blades). 
Based on these figures, the total cost impact of the AD on U.S. 
operators is estimated to be $65,168 per year for the first year and 
approximately $64,228 for each of the next 5 years thereafter, assuming 
24 of the affected blades (approximately 1/6 of the fleet or the blades 
on 8 helicopters) in the fleet are removed, repaired, and reinstalled 
with replacement abrasion strips each year, and that all affected 
helicopters are subjected to one repetitive inspection each year, 
including the first year.
    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 final evaluation has been prepared for this action 
and it is contained in the Rules Docket. A copy of it may be obtained 
from the Rules Docket at the FAA, Office of the Regional Counsel, 
Southwest Region, Attention: Rules Docket No. 98-SW-39-AD, 2601 Meacham 
Blvd., Room 663, Fort Worth, Texas 76137.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, 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 U.S.C. 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding a new airworthiness directive 
to read as follows:

AD 99-04-14  Schweizer Aircraft Corporation: Amendment 39-11038. 
Docket No. 98-SW-39-AD.

    Applicability: Model 269C-1 helicopters with main rotor blades, 
P/N 269A1185-1, S/N S222, S312, S313, S325, S326, S327, S339, S341, 
S343, S346, S347, S349 through S367, S369 through S377, S379 through 
S391, S393, S394, S395, S397, S399, S401 through S417, S419 through 
S424, S426 through S449, S451 through S507, S509 through S513, S516 
through S527, S529 through S540, S542, S544 through S560, S562 
through S584, S586 through S595, S597 though S611, S620 through 
S623, S625, S628, S633, S641 through S644, S646, S653, S658, S664, 
S665, and S667, installed, certificated in any category.


[[Page 7494]]


    Note 1: This AD applies to each helicopter 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 helicopters that have been modified, 
altered, or repaired so that the performance of the requirements of 
this AD is affected, the owner/operator must use the authority 
provided in paragraph (e) to request approval from the FAA. This 
approval may address either no action, if the current configuration 
eliminates the unsafe condition, or different actions necessary to 
address the unsafe condition described in this AD. Such a request 
should include an assessment of the effect of the changed 
configuration on the unsafe condition addressed by this AD. In no 
case does the presence of any modification, alteration, or repair 
remove any helicopter from the applicability of this AD.

    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent loss of the abrasion strip from a main rotor blade 
(blade) and subsequent loss of control of the helicopter, accomplish 
the following:
    (a) Within the next 50 hours time-in-service (TIS), or within 90 
calendar days after the effective date of this AD, whichever is 
earlier, or prior to installing an affected replacement blade, and 
thereafter at intervals not to exceed 50 hours TIS from the date of 
the last inspection or replacement installation:
    (1) Visually inspect the adhesive bead around the perimeter of 
each abrasion strip for erosion, cracks, or blisters.
    (2) Visually inspect the bond line between each abrasion strip 
and each blade skin for voids, separation, or lifting of the 
abrasion strip.
    (3) Inspect each abrasion strip for debonding or hidden 
corrosion voids using a tap (ring) test as described in the 
applicable maintenance manual.
    (b) If any deterioration of an abrasion strip adhesive bead is 
discovered, prior to further flight, restore the bead in accordance 
with the applicable maintenance manual.
    (c) If abrasion strip debonding, separation, or a hidden 
corrosion void is found or suspected, prior to further flight, 
remove the blade with the defective abrasion strip and replace it 
with an airworthy blade.
    (d) Rebonding of an affected blade's abrasion strip is 
considered a terminating action for the requirements of this AD for 
that blade. Identify a blade that has a rebonded strip by adding a 
white dot adjacent to the blade S/N.
    (e) An 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, New York Aircraft Certification 
Office, FAA. Operators shall submit their requests through an FAA 
Principal Maintenance Inspector, who may concur or comment and then 
send it to the Manager, New York Aircraft Certification Office.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the New York Aircraft Certification Office.

    (f) 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 helicopter to a location where 
the requirements of this AD can be accomplished, provided the 
abrasion strip has not started to separate or debond from the main 
rotor blade.
    (g) This amendment becomes effective on March 23, 1999.

    Issued in Fort Worth, Texas, on February 5, 1999.
Eric Bries,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 99-3588 Filed 2-12-99; 8:45 am]
BILLING CODE 4910-13-U

The complete text was extracted from the official GovInfo HTML edition for this publication. Acquired 2026-10-09T04:53:15.362596+00:00. Text extraction preserves the recorded source wording; it does not determine current requirements.

Open the captured official edition

Source SHA-256

a1c098ce6c5d79976a18d2597115254b9f250cb9df8479e4789652b0f412ab3d

Text SHA-256

d09d0f942db07737fa2251493b0b416f8900ca737ef0a0c06e69de383cd158f6