[Federal Register: January 14, 2004 (Volume 69, Number 9)]
[Rules and Regulations]
[Page 2059-2062]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr14ja04-1]
========================================================================
Rules and Regulations
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains regulatory documents
having general applicability and legal effect, most of which are keyed
to and codified in the Code of Federal Regulations, which is published
under 50 titles pursuant to 44 U.S.C. 1510.
The Code of Federal Regulations is sold by the Superintendent of Documents.
Prices of new books are listed in the first FEDERAL REGISTER issue of each
week.
========================================================================
[[Page 2059]]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2003-CE-16-AD; Amendment 39-13427; AD 2004-01-13]
RIN 2120-AA64
Airworthiness Directives; Raytheon Aircraft Company Model 1900,
1900C, and 1900D Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: The FAA supersedes Airworthiness Directive (AD) 97-22-16,
which applies to certain Raytheon Model 1900, 1900C, and 1900D
airplanes. AD 97-22-16 currently requires you to replace the bearings
on the vent blower assemblies with improved design bearings and install
a thermal protection device for the vent blowers. That AD resulted from
reports of vent blower assembly bearings seizing and locking the blower
motor on several of the affected airplanes. This AD retains the actions
required in AD 97-22-16 for certain vent blower assemblies and requires
you to incorporate further product improvement modifications on all
affected vent blower assemblies. This AD is the result of reports that
vent blower assemblies modified in accordance with AD 97-22-16 are
still malfunctioning. We are issuing this AD to prevent smoke from
entering the cockpit and cabin due to the current configuration of vent
blower assemblies, which could result in the pilot becoming
incapacitated or impairing her/his judgment. Such a condition could
lead to the pilot not being able to make critical flight safety
decisions and result in loss of control of the airplane.
DATES: This AD becomes effective on February 19, 2004.
As of February 19, 2004, the Director of the Federal Register
approved the incorporation by reference of certain publications listed
in the regulation.
ADDRESSES: You may get the service information identified in this AD
from Raytheon Aircraft Company, 9709 E. Central, Wichita, Kansas 67201-
0085; telephone: (800) 429-5372 or (316) 676-3140.
You may view the AD docket at FAA, Central Region, Office of the
Regional Counsel, Attention: Rules Docket No. 2003-CE-16-AD, 901
Locust, Room 506, Kansas City, Missouri 64106. Office hours are 8 a.m.
to 4 p.m., Monday through Friday, except Federal holidays.
FOR FURTHER INFORMATION CONTACT: Dan Withers, Aerospace Engineer,
Wichita Aircraft Certification Office, FAA, 1801 Airport Road, Wichita,
Kansas 67209; telephone: (316) 946-4196; facsimile: (316) 946-4107.
SUPPLEMENTARY INFORMATION:
Discussion
What events have caused this AD? Reports of the vent blower
assembly bearings seizing and locking the blower motor on several
Raytheon Model 1900, 1900C, and 1900D airplanes caused us to issue AD
97-22-16, Amendment 39-10187 (62 FR 58894, October 31, 1997. AD 97-22-
16 currently requires the following on certain Raytheon Model 1900,
1900C, and 1900D airplanes:
--Incorporating a modification to replace the bearings in the vent
blower assemblies with improved design bearings (Electromech
Technologies Kit No. EM630-201-1 or EM630-201-2 (as appropriate for the
blower serial number)); and
--Installing a thermal protection for the vent blowers (Electromech
Technologies Kit No. EM630-201-1 or EM630-201-2 or Advanced Industries
Kit No. BC80A905 (as appropriate for the blower serial number)).
What has happened since AD 97-22-16 to initiate this action? The
FAA has received reports that vent blower assemblies modified in
accordance with AD 97-22-16 are still malfunctioning.
What is the potential impact if FAA took no action? If not
corrected, smoke could enter the cockpit and cabin, which could result
in the pilot becoming incapacitated or impairing her/his judgment. This
condition could lead to the pilot not being able to make critical
flight safety decisions and result in loss of control of the airplane.
Has FAA taken any action to this point? We issued 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 Model 1900, 1900C,
and 1900D airplanes. This proposal was published in the Federal
Register as a notice of proposed rulemaking (NPRM) on June 4, 2003 (68
FR 33420). The NPRM proposed to supersede AD 97-22-16 with a new AD
that would retain the actions required in AD 97-22-16 for certain vent
blower assemblies and require you to incorporate further product
improvement modifications for all affected vent blower assemblies.
Comments
Was the public invited to comment? We provided the public the
opportunity to participate in the development of this AD. The following
presents the comments received on the proposal and FAA's response to
each comment:
Comment Issue: The Proposed AD Does Not Solve the Problem of Smoke in
the Cockpit/Cabin
What is the commenter's concern? The commenter states that the
proposed AD focuses on the vent blower low speed resistors and does not
consider the motor as a source of smoke. Since the cooling air for the
motor is drawn through the motor by the blower intake and then is
exhausted into the cabin, any motor failure that generates smoke and
fumes is blown directly into the cabin.
The following summarizes the commenter's concerns:
--The insulation on the lead-wire can hang up on the brush holder if
the brush lead-wire is pushed down to clear the metal brush inspection
cover. The installation instructions provided with Modification Kit
BC80A-901-3, which incorporates the replacement brushes with the lead-
wire insulation, do not clarify where the lead-wires should be formed;
--When a brush lead-wire gets hung up on the brush holder (caused by
improper lead-wire forming), there is little to no force from the
spring to hold the brush against the
[[Page 2060]]
commutator. Lack of force to hold the brush against the commutator can
cause arcing between the brush and commutator surface, which produces
tremendous heat and accelerated brush wear. This will ultimately lead
to excess heat that will cause the grease to boil out of the bearings
and result in bearing failure;
--The hard anodized coating on the metal brush inspection cover
provided with Modification Kit No. 630-203-1 is a poor insulator and is
easily scratched during assembly and disassembly. Once scratched, the
coating offers no insulation, which creates the possibility for a short
circuit to the brush shunt; and
--The low speed power resistors are considered undersized for the
application.
The commenter recommends the following:
--Installing thermal fuse(s) on the motor to interrupt the current in
the event of the motor overheating;
--Controlling how the brush lead-wires are formed to prevent shorting
to metal inspection screen or any other adjacent conductor; and
--Increasing the power rating of the low speed resistors to improve the
safety margin.
The commenter requests these changes based on personal repair
history as well as analysis of the design.
What is FAA's response to the concern? We do not agree. Although
the commenter raises many pertinent concerns, we consider the requested
changes a product improvement or a way to increase the reliability of
the motor.
The proposed AD is intended to address smoke in the cabin/cockpit
that is specifically caused by the vent blower assembly. Investigation
by Raytheon engineering concluded that all incidents involving smoke in
the cockpit/cabin were caused by overheating of the vent blower low
speed resistors while operating the blower on low speed.
AD 97-22-16 required incorporating the applicable modification kit
as specified in Raytheon Service Bulletin No. 2721, Issued: January,
1997. Raytheon Service Bulletin No. 2721 added a 216[deg]C thermal
cutout to the resistor assembly to interrupt power to the resistors and
prevent overheating.
Further field experience revealed that the 216[deg]C cutout may not
open soon enough to prevent overheating in all instances. As a result,
Raytheon issued Mandatory Service Bulletin SB 21-3448, Issued: October,
2002, to decrease the thermal cutout set point to 152[deg]C. New tests
verified that this value cutout to the resistor assembly provides
adequate protection against resistor overheating while avoiding
nuisance trips during normal operation.
The addition of an insulating sleeve over the brush lead-wires and
hard anodizing of the brush inspection cover required by Raytheon
Mandatory Service Bulletin SB 21-3448, Issued: October, 2002, was done
to offer an additional measure of protection. The additions are not
meant to substitute proper brush lead-wire routing.
The thermal cutout on the resistors and the aircraft's blower
circuit current limiter are the primary methods of protection. If a
brush lead-wire was shorted to the housing and the vent blower was
operated in the low speed mode, the increased current flow would cause
the resistor temperature to increase until the thermal cutout opens and
interrupts power to the resistors. If a brush lead-wire was shorted to
the housing and the vent blower was operated in the high speed mode,
the increased current flow would cause the aircraft's current limiter
to open and interrupt power.
A brush lead-wire could possibly get hung up with or without the
sleeving. If the brush lead-wire gets hung up, this would result in
arcing between the brush and commutator resulting in increased heat and
accelerated brush wear until the blower no longer continues to operate.
At this time, the manufacturer has not received any field reports of
smoke related to ``hung brushes.''
The power dissipation in the low speed circuit does appear to be
above the rated value for the resistors. However, this does not account
for the large amount of cooling airflow that passes over the area to
which the resistors are mounted. Service history shows that the
resistor rating is adequate under normal operations. If the resistors
start to overheat because of vent blower failure, then the thermal
cutout will open and interrupt power to the resistor assembly.
Since none of the recommendations specifically address an unsafe
condition, we have determined that we are not changing the final rule
AD based on these comments.
Conclusion
What is FAA's final determination on this issue? We have carefully
reviewed the available data and determined that air safety and the
public interest require adopting the AD as proposed except for minor
editorial corrections. We have determined that these minor corrections:
--Are consistent with the intent that was proposed in the NPRM for
correcting the unsafe condition; and
--Do not add any additional burden upon the public than was already
proposed in the NPRM.
Changes to 14 CFR Part 39--Effect on the AD
How does the revision to 14 CFR part 39 affect this AD? On July 10,
2002, the FAA published a new version of 14 CFR part 39 (67 FR 47997,
July 22, 2002), which governs the FAA's AD system. This regulation now
includes material that relates to altered products, special flight
permits, and alternative methods of compliance. This material
previously was included in each individual AD. Since this material is
included in 14 CFR part 39, we will not include it in future AD
actions.
Costs of Compliance
How many airplanes does this AD impact? We estimate that this AD
affects 300 airplanes in the U.S. registry.
What is the cost impact of this AD on owners/operators of the
affected airplanes? We estimate the following costs to accomplish the
modification:
----------------------------------------------------------------------------------------------------------------
Total cost per Total cost on U.S.
Labor cost Parts cost airplane operators
----------------------------------------------------------------------------------------------------------------
3 workhours x $60 per hour = $180....... $415 (for both the forward $595 $595 x 300 = $178,500.
and aft ventilation blower
assemblies).
----------------------------------------------------------------------------------------------------------------
Regulatory Findings
Will this AD impact various entities? We have determined that this
AD will not have federalism implications under Executive Order 13132.
This AD will not have a substantial direct effect 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.
[[Page 2061]]
Will this AD involve a significant rule or regulatory action? For
the reasons discussed above, I certify that this AD:
1. Is not a ``significant regulatory action'' under Executive Order
12866;
2. Is not a ``significant rule'' under the 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.
We prepared a summary of the costs to comply with this AD and
placed it in the AD Docket. You may get a copy of this summary by
sending a request to us at the address listed under ADDRESSES. Include
``AD Docket No. 2003-CE-16-AD'' in your request.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
0
Accordingly, under 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
0
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]
0
2. FAA amends Sec. 39.13 by removing Airworthiness Directive (AD) 97-
22-16, Amendment 39-10187 (62 FR 58894, October 31, 1997), and by
adding a new AD to read as follows:
2004-01-13 Raytheon Aircraft Company: Amendment 39-13427; Docket No.
2003-CE-16-AD; Supersedes AD 97-22-16, Amendment 39-10187.
When Does This AD Become Effective?
(a) This AD becomes effective on February 19, 2004.
What Other ADs Are Affected by This Action?
(b) This AD supersedes AD 97-22-16, Amendment 39-10187 (62 FR
58894, October 31, 1997).
What Airplanes Are Affected by This AD?
(c) This AD affects the following airplane models and serial
numbers that are:
(1) certificated in any category; and
(2) equipped with vent blower assembly, part number 114-380028-
1, 114-380028-3, 114-380028-5, or 114-380028-7.
------------------------------------------------------------------------
Model Serial numbers
------------------------------------------------------------------------
1900.................................. UA-3.
1900C................................. UB-1 through UB-74 and UC-1
through UC-174.
1900 (C-12J).......................... UD-1 through UD-6.
1900D................................. UE-1 through UE-427.
------------------------------------------------------------------------
What Is the Unsafe Condition Presented in This AD?
(d) This AD is the result of reports that vent blower assemblies
modified in accordance with AD 97-22-16 are still malfunctioning.
The actions specified in this AD are intended to prevent smoke from
entering the cockpit and cabin due to the current configuration of
vent blower assemblies, which could result in the pilot becoming
incapacitated or impairing his/her judgment. This condition could
lead to the pilot not being able to make critical flight safety
decisions and result in loss of control of the airplane.
What Must I Do To Address This Problem?
(e) To address this problem, you must do the following:
------------------------------------------------------------------------
Actions Compliance Procedures
------------------------------------------------------------------------
(1) Check the maintenance Within the next Follow Raytheon
records to determine if a part 800 hours time-in- Aircraft
number (P/N) 114-380028-1, 114- service (TIS) Mandatory Service
380028-3, 114-380028-5, or 114- after February Bulletin SB 21-
380028-7 ventilation blower 19, 2004 (the 3448, Issued:
assembly is installed. effective date of October, 2002.
this AD), unless The owner/
already done. operator holding
at least a
private pilot
certificate as
authorized by
section 43.7 of
the Federal
Aviation
Regulations (14
CFR 43.7) may
perform this
check.
(2) If, by checking the Prior to further The owner/operator
maintenance records, the owner/ flight after the holding at least
operator can definitely show maintenance a private pilot
that a P/N 114-380028-1, 114- records check certificate as
380028-3, 114-380028-5, or 114- required in authorized by
380028-7 ventilation blower paragraph (e)(1) section 43.7 of
assembly is not installed, no of this AD. the Federal
further action is required by Aviation
this AD. Make an entry into the Regulations (14
aircraft records showing CFR 43.7) may
compliance with this portion of make this entry.
the AD in accordance with
section 43.9 of the Federal
Aviation Regulations (14 CFR
43.9).
(3) If, by checking the Do all Following Raytheon
maintenance records, the owner/ modifications Aircraft
operator can definitely show prior to further Mandatory Service
that a P/N 114-380028-1, 114- flight after the Bulletin SB 21-
380028-3, 114-380028-5, or 114- maintenance 3448, Issued:
380028-7 ventilation blower records check October, 2002,
assembly is installed, do the required in and Raytheon
following for each P/N:. paragraph (e)(1) Service Bulletin
unless already No. 2721, Issued:
done. January, 1997.
(i) P/N 114-380028-1: modify
following Raytheon Service
Bulletin No. 2721, Issued:
January, 1997, prior to
incorporating Electromechanic
Technologies Modification Kit
No. P/N 630-203-01 and changing
the P/N to 114-380028-11.
(ii) P/N 114-380028-3:
incorporate Advanced Industries
Modification Kit No. P/N BC80A-
901-3 and change the P/N to 114-
380028-9.
(iii) P/N 114-380028-5 with a
serial number (S/N) of 2162 or
above or with a S/N of 2162
with an ``A'' suffix: no
modification is required.
Change the P/N to 114-380028-11
and make an entry into the
aircraft records that shows
compliance with this portion of
the AD in accordance with
section 43.9 of the Federal
Aviation Regulations (14 CFR
43.9).
[[Page 2062]]
(iv) P/N 114-380028-5 with a S/N
prior to 2162 without an ``A''
suffix: incorporate
Electromechanic Technologies
Modification Kit No. P/N 630-
203-01 and change the P/N to
114-380028-11.
(v) P/N 114-380028-7:
incorporate Advanced Industries
Modification Kit No. P/N BC80A-
901-3 and change the P/N to 114-
380028-9.
(4) If the owner/operator cannot Inspect within the Follow Raytheon
definitely show that a P/N 114- next 800 hours Aircraft
380028-1, 114-380028-3, 114- TIS after Mandatory Service
380028-5, or 114-380028-7 February 19, 2004 Bulletin SB 21-
ventilation blower assembly is (the effective 3448, Issued:
installed through the date of this AD). October, 2002,
maintenance records check, an Do all and Raytheon
appropriately-rated mechanic modifications Service Bulletin
must do an inspection to prior to further No. 2721, Issued:
determine the P/N of the flight. January, 1997.
installed ventilation blower
assembly and do the applicable
modification required in
paragraphs (e)(3)(i),
(e)(3)(ii), (e)(3)(iii),
(e)(3)(iv), and (e)(3)(v) of
this AD.
(5) Do not install any P/N 114- As of February 19, Follow Raytheon
380028-1, 114-380028-3, 114- 2004 (the Aircraft
380028-5, or 114-380028-7 effective date of Mandatory Service
ventilation blower assembly, this AD). Bulletin SB 21-
unless it has been modified as 3448, Issued:
specified in paragraphs October, 2002,
(e)(3)(i), (e)(3)(ii), and Raytheon
(e)(3)(iii), (e)(3)(iv), and Service Bulletin
(e)(3)(v) of this AD. No. 2721, Issued:
January, 1997.
------------------------------------------------------------------------
May I Request an Alternative Method of Compliance?
(f) You may request a different method of compliance or a
different compliance time for this AD by following the procedures in
14 CFR 39.13.
(1) Send your request to the Manager, Wichita Aircraft
Certification Office (ACO), FAA. For information on any already
approved alternative methods of compliance, contact Dan Withers,
Aerospace Engineer, Wichita Aircraft Certification Office, FAA, 1801
Airport Road, Wichita, Kansas 67209; telephone: (316) 946-4196;
facsimile: (316) 946-4107.
(2) Alternative methods of compliance approved in accordance
with AD 97-22-16, which is superseded by this AD, are not approved
as alternative methods of compliance with this AD.
Does This AD Incorporate Any Material by Reference?
(g) You must do the actions required by this AD following the
instructions in Raytheon Aircraft Mandatory Service Bulletin SB 21-
3448, Issued: October, 2002, and Raytheon Aircraft Mandatory Service
Bulletin No. 2721, Issued: January, 1997. The Director of the
Federal Register approved the incorporation by reference of this
service bulletin in accordance with 5 U.S.C. 552(a) and 1 CFR part
51. You may get a copy from Raytheon Aircraft Company, 9709 E.
Central, Wichita, Kansas 67201-0085; telephone: (800) 429-5372 or
(316) 676-3140. You may review copies at FAA, Central Region, Office
of the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri
64106; or at the Office of the Federal Register, 800 North Capitol
Street, NW., suite 700, Washington, DC.
Issued in Kansas City, Missouri, on January 2, 2004.
David R. Showers,
Acting Manager, Small Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 04-474 Filed 1-13-04; 8:45 am]
BILLING CODE 4910-13-P