[Federal Register Volume 59, Number 197 (Thursday, October 13, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-25289]


[[Page Unknown]]

[Federal Register: October 13, 1994]


                                                   VOL. 59, NO. 197

                                         Thursday, October 13, 1994

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 92-CE-22-AD]

 

Airworthiness Directives; Jetstream Aircraft Limited (Formerly 
British Aerospace, Regional Airlines Limited) Jetstream Model 3101 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Supplemental notice of proposed rulemaking (NPRM); Reopening of 
the comment period.

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

SUMMARY: This document proposes to revise an earlier proposed 
airworthiness directive (AD), which would have superseded AD 91-08-01. 
That AD currently requires the following on Jetstream Aircraft Limited 
(JAL) Jetstream Model 3101 airplanes: revising the maximum speed for 
flaps at 50 degrees from 153/149 knots indicated airspeed (KIAS) to 130 
KIAS; and limiting the maximum flap extension to 20 degrees anytime ice 
is present on the airplane. The previous notice proposed to provide the 
option of incorporating a flap system modification that would eliminate 
the requirements of AD 91-08-01. Since publication of that proposal, 
the Federal Aviation Administration (FAA) has re-examined all 
information related to this subject, and has determined that the flap 
system modification should be made mandatory rather than optional. The 
proposed actions are intended to prevent sudden pitch down of the 
airplane during icing conditions, which could lead to loss of control 
of the airplane.

DATES: Comments must be received on or before December 16 1994.

ADDRESSES: Submit comments in triplicate to the FAA, Central Region, 
Office of the Assistant Chief Counsel, Attention: Rules Docket No. 92-
CE-22-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 Jetstream Aircraft Limited, Manager Product Support, Prestwick 
Airport, Ayrshire, KA9 2RW Scotland; telephone (44-292) 79888; 
facsimile (44-292) 79703; or Jetstream Aircraft Inc., Librarian, P.O. 
Box 16029, Dulles International Airport, Washington, DC 20041-6029; 
telephone (703) 406-1161; facsimile (703) 406-1469. This information 
also may be examined at the Rules Docket at the address above.

FOR FURTHER INFORMATION CONTACT: Mr. Raymond A. Stoer, Program Officer, 
Brussels Aircraft Certification Office, FAA, Europe, Africa, and Middle 
East Office, c/o American Embassy, B-1000 Brussels, Belgium; telephone 
(322) 513.3830; facsimile (322) 230.6899; or Mr. John P. Dow, Sr., 
Project Officer, Small Airplane Directorate, Airplane Certification 
Service, FAA, 1201 Walnut, suite 900, Kansas City, Missouri 64106; 
telephone (816) 426-6932; facsimile (816) 426-2169.

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. 92-CE-22- 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. 92-CE-22-AD, Room 1558, 601 E. 12th Street, 
Kansas City, Missouri 64106.

Discussion

    A proposal to amend part 39 of the Federal Aviation Regulations (14 
CFR part 39) to include an AD that would apply to certain JAL Jetstream 
Model 3101 airplanes was published in the Federal Register on July 8, 
1992 (57 FR 30174). That action proposed to supersede AD 91-08-01 with 
a new AD that would (1) retain the flap system operating revision and 
limitation currently required by AD 91-08-01; and (2) limit the 
applicability to only those airplanes that do not have the flap system 
modified in accordance with British Aerospace (BAe) Service Bulletin 
27-JA 910541.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. One comment was received in agreement 
with the proposed AD and no comments were received concerning the FAA's 
determination of the cost upon the public.
    Since issuing that action, the FAA has re-examined all available 
information on this issue, and has determined that the limitation of 
maximum flap setting of 20 degrees in icing conditions presents an 
unsafe condition in certain circumstances.
    The Jetstream Model 3101 airplane has a feature known as ``lift 
dump'', which allows for proper deceleration by automatically extending 
flaps from the 50 degree position to the 70 degree position when the 
nose wheel strut is compressed during landing. When landing with a flap 
setting of 20 degrees, ``lift dump'' is not normally available, which 
can make deceleration more dependent upon propeller reverse or manual 
selection.
    Propeller reverse is utilized in normal operation as an aid in 
reducing landing roll distance. The other option is manually selecting 
flaps from 20 degrees to 50 degrees immediately after touchdown while 
the airplane is traveling at a higher speed. When the operator selects 
the 50-degree position with all ground logic constraints satisfied, the 
flaps will extend to the 70-degree position. This technique can result 
in high aerodynamic loads upon the flap, which could cause structural 
damage that, if not detected and corrected, could result in loss of 
airplane directional control caused by failure of the flap system. 
Also, there is a temporary increase in wing lift when manually 
extending the wings from 20 degrees to 35 degrees, which could result 
in the airplane becoming airborne or a reduction of directional control 
and braking force.
    Because ``lift dump'' is available with the flaps at the 35-degree 
position during landing, the FAA has determined that (1) the flap 
system modification that allows the use of flaps at 35-degrees with ice 
visible should be incorporated; and (2) AD action should be taken to 
prevent sudden pitch down of the airplane during icing conditions, 
which could lead to loss of control of the airplane.
    Since incorporating the 35 degrees flap modification into the 
notice of proposed rulemaking specifies additional procedures that go 
beyond the scope of what was originally proposed, the notice has been 
revised accordingly and the comment period has been reopened to provide 
additional time for public comment. The proposed AD would supersede AD 
91-08-01 with a new AD that would (1) retain the flap system operating 
revision and limitation currently required until the 35-degree flap 
system modification was incorporated; and (2) eventually require 
incorporating the 35-degree flap system modification in accordance with 
the instructions in Jetstream Aircraft Limited SB No. 27-JA 910541, 
which consists of the following pages: 

------------------------------------------------------------------------
       Page Nos.             Revision level                Date         
------------------------------------------------------------------------
2, 5 through 30 and 33   Revision 1.............  November 11, 1991.    
 through 45.                                                            
31.....................  Revision 2.............  February 4, 1992.     
1, 3, 4, and 32........  Revision 3.............  November 16, 1992.    
------------------------------------------------------------------------

    The FAA estimates that 141 airplanes in the U.S. registry would be 
affected by the proposed AD, that it would take approximately 23 
workhours per airplane to accomplish the proposed modification, and 
that the average labor rate is approximately $55 an hour. The 
manufacturer will provide parts at no cost to the owner/operator. Based 
on these figures, the total cost impact of the proposed AD on U.S. 
operators is estimated to be $194,580. This figure is based on the 
assumption that no affected owner/operator has incorporated the 
proposed modification.
    Jetstream Aircraft Limited has informed the FAA that 122 
modification kits have been delivered to affected airplane owners/
operators. Since each of these airplane operators have incorporated 
revised flight manual supplements, the FAA assumes that each of these 
kits is installed on one of the affected airplanes. With this in mind, 
the proposed cost impact upon U.S. operators would be reduced $168,300 
from $194,580 to $26,220. In addition, Jetstream Aircraft Limited 
informed the FAA that the other 19 affected airplanes are in the 
storage inventory of their sister company JSX. The policy of JSX is to 
incorporate this modification before distributing one of the affected 
airplanes to an operator. Taking these factors into consideration, the 
proposed AD would provide no economic cost impact upon U.S. operators.
    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 
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. 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 91-08-01, Amendment 39-
7007 (56 FR 24333, May 30, 1991), and adding a new AD to read as 
follows:

Jetstream Aircraft Limited: Docket No. 92-CE-22-AD. Supersedes AD 
91-08-01, Amendment 39-7007.

    Applicability: Jetstream Model 3101 airplanes (all serial 
numbers), certificated in any category, that do not have the flap 
system modified in accordance with the ACCOMPLISHMENT INSTRUCTIONS 
section of Jetstream Aircraft Limited Service Bulletin (SB) 27-JA 
910541, which consists of the following pages and revision levels: 

------------------------------------------------------------------------
       Page Nos.              Revision level               Date         
------------------------------------------------------------------------
2, 5 through 30 and 33   Revision 1.............  November 11, 1991.    
 through 45.                                                            
31.....................  Revision 2.............  February 4, 1992.     
1, 3, 4, and 32........  Revision 3.............  November 16, 1992.    
------------------------------------------------------------------------

    Note 1: Compliance with a different revision level of the above-
referenced service bulletin fulfills the applicable requirements of 
this AD.

    Compliance: Required as indicated after the effective date of 
this AD, unless already accomplished.
    To prevent sudden pitch down of the airplane during icing 
conditions, which could lead to loss of control of the airplane, 
accomplish the following:
    (a) Within the next 10 hours time-in-service (TIS) after June 
10, 1991 (the effective date of superseded AD 91-08-01), accomplish 
the following:
    (1) Modify the operating limitations placards located on the 
flight deck in accordance with Jetstream Alert SB No. 27-A-JA 
910340, dated March 25, 1991. This modification will limit the 
maximum flap extension speed at the 50-degree position to 130 knots 
indicated airspeed (KIAS).
    (2) Insert a copy of this AD into the limitations section of the 
airplane flight manual.
    (b) Within the next 25 hours TIS after June 10, 1991 (the 
effective date of superseded AD 91-08-01), accomplish the following:
    (1) Fabricate a placard with the words ``Do not extend the flaps 
beyond the 20-degree position if ice is visible on the airplane and 
ensure that the landing gear selector is down prior to landing.'' 
Install this placard on the airplane's instrument panel within the 
pilot's clear view. Parts of the airplane where ice could 
specifically be visible include the windshield wipers, center 
windshield, propeller spinners, or inboard wing leading edges.
    (2) Operate the airplane in accordance with BAe CAA-Mandatory 
Alert Service Bulletin 27-A-JA 910340, dated March 25, 1991, Section 
2.B.-Instruction for Aircraft Operations, paragraphs (1)(a) and 
(1)(c) until Amendments P/32, P/49, and P/52 have been received. 
Upon receipt, incorporate these amendments into Airplane Flight 
Manual (AFM) HP.4.10. Ensure that Amendment  G/10 is incorporated 
into AFM HP.4.10.
    (c) Within the next 100 hours TIS after the effective date of 
this AD, incorporate the 35-degree flap modification (Amendment JA 
910541) in accordance with the ACCOMPLISHMENT INSTRUCTIONS section 
of Jetstream Aircraft Limited SB 27-JA 910541.
    (d) The actions required by paragraphs (a) and (b) of this AD 
may be terminated when the flap system is modified in accordance 
with Jetstream Aircraft Limited SB 27-JA 910541.
    (e) Special flight permits may be issued in accordance with 
Sec. Sec. 21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR 21.197 and 21.199) to operate airplanes to a location where the 
requirements of this AD can be accomplished.
    (f) An alternative method of compliance or adjustment of the 
compliance times that provides an equivalent level of safety may be 
approved by the Manager, Brussels Aircraft Certification Office, 
FAA, Europe, Africa, and Middle East Office, c/o American Embassy, 
B-1000 Brussels, Belgium. The request should be forwarded through an 
appropriate FAA Maintenance Inspector, who may add comments and then 
send it to the Manager, Brussels 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 Brussels Aircraft Certification Office.

    (g) All persons affected by this directive may obtain copies of 
the documents referred to herein upon request to Jetstream Aircraft 
Limited, Manager Product Support, Prestwick Airport, Ayrshire, KA9 
2RW Scotland; telephone (44-292) 79888; or Jetstream Aircraft Inc., 
Librarian, P.O. Box 16029, Dulles International Airport, Washington, 
DC, 20041-6029; or may examine these documents at the FAA, Central 
Region, Office of the Assistant Chief Counsel, Room 1558, 601 E. 
12th Street, Kansas City, Missouri 64106.
    (h) This amendment supersedes AD 91-08-01, Amendment 39-7007.

    Issued in Kansas City, Missouri, on October 5, 1994.
John R. Colomy,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-25289 Filed 10-12-94; 8:45 am]
BILLING CODE 4910-13-U