[Federal Register Volume 65, Number 17 (Wednesday, January 26, 2000)]
[Rules and Regulations]
[Pages 4095-4099]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-1772]



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  Federal Register / Vol. 65, No. 17 / Wednesday, January 26, 2000 / 
Rules and Regulations  

[[Page 4095]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-179-AD; Amendment 39-11531; AD 2000-02-13]
RIN 2120-AA64


Airworthiness Directives; de Havilland Model DHC-8-100, -200, and 
-300 Series Airplanes

AGENCY:  Federal Aviation Administration, DOT.

ACTION:  Final rule.

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

SUMMARY:  This amendment adopts a new airworthiness directive (AD), 
applicable to all de Havilland Model DHC-8-100, -200, and -300 series 
airplanes, that requires installation of a placard on the instrument 
panel of the cockpit to advise the flightcrew that positioning of the 
power levers below the flight idle stop during flight is prohibited. 
This amendment also requires eventual installation of a system that 
will prevent such positioning of the power levers during flight. Such 
installation will terminate the requirement for installation of a 
placard. This amendment is prompted by reports of operation of the 
airplane with the power levers positioned below the flight idle stop 
during flight. The actions specified by this AD are intended to prevent 
such positioning of the power levers below the flight idle stop during 
flight, which could cause engine overspeed, possible engine damage or 
failure, and consequent reduced controllability of the airplane.

EFFECTIVE DATE:  March 1, 2000.

FOR FURTHER INFORMATION CONTACT:  James E. Delisio, Aerospace Engineer, 
Airframe and Propulsion Branch, ANE-171, FAA, Engine and Propeller 
Directorate, New York Aircraft Certification Office, 10 Fifth Street, 
Third Floor, Valley Stream, New York 11581; telephone (516) 256-7521; 
fax (516) 568-2716.

ADDRESSES:  Information pertaining to this amendment may be examined at 
the Federal Aviation Administration (FAA), Transport Airplane 
Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton, Washington; 
or at the FAA, Engine and Propeller Directorate, New York Aircraft 
Certification Office, 10 Fifth Street, Third Floor, Valley Stream, New 
York.

SUPPLEMENTARY INFORMATION:  A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an airworthiness 
directive (AD) that is applicable to all de Havilland Model DHC-8-100, 
-200, and -300 series airplanes was published in the Federal Register 
on July 7, 1998 (63 FR 36619). That action proposed to require 
installation of a placard on the instrument panel of the cockpit to 
advise the flightcrew that positioning of the power levers below the 
flight idle stop during flight is prohibited. Additionally, that action 
proposed to require eventual installation of an FAA-approved system 
that would prevent such positioning of the power levers during flight. 
Installation of that system would eliminate the requirement for 
installation of the placard.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.

1. Support for the Proposal

    One commenter supports the proposed rule.

2. Request to Withdraw the Proposal: No Unsafe Condition

    Several commenters point out the following: No new incidents of 
beta during flight have been reported since 1996, and reports were from 
foreign operators. Since those previous reports, the AFM has been 
revised to prohibit positioning of the power levers below the flight 
idle stop (beta) during flight, and the pilot training syllabus on 
prohibition of beta during flight has been revised. The commenters 
further state that sufficient tactile, visual, and audio cues exist to 
advise the flightcrew if the propeller is in beta range. One commenter, 
the manufacturer, points out that the power lever triggers cannot be 
applied accidentally. Movement of the triggers requires purposeful 
``reach and lift'' action to engage beta. Therefore, the manufacturer 
asserts that unintentional engagement of beta during flight cannot 
occur. Another commenter states that a mechanical system cannot 
preclude inappropriate operation; however, proper training of pilots 
can. These commenters conclude that, with the previously mentioned 
procedures already in place, the unsafe condition specified in the 
proposed rule does not exist.
    The FAA does not concur that the subject unsafe condition does not 
exist in Model DHC-8 series airplanes. The FAA acknowledges that other 
safeguards currently in practice, such as AFM revisions and the revised 
pilot training syllabus, do provide certain tactile, visual, and audio 
cues. (See Comment 7 for related discussion on visual cues.) However, 
despite the implementation of those safeguards, the FAA has received 
reports of operation of the airplane with the power levers positioned 
below the flight idle stop during flight on de Havilland Model DHC-8 
series airplanes. One report indicated that such operation resulted in 
significant engine damage. Therefore, the FAA considers that sufficient 
data exist to demonstrate that an unsafe condition exists on Model DHC-
8 series airplanes. Further, the FAA has determined that positioning of 
the power levers below the flight idle stop could result in engine 
overspeed, possible engine damage or failure, and consequent reduced 
controllability of the airplane.

3. Request to Withdraw the Proposal: Airplane Already Meets Intent 
of 14 CFR Part 25.1155

    Several commenters state that the current design meets the 
requirements of part 25 of the Federal Aviation Regulations (14 CFR 
part 25.1155), and one other commenter asserts that the current design 
already goes beyond those requirements. One of the commenters points 
out that part 25 of the Federal Aviation Regulations (14 CFR part 25) 
only addresses unintentional or uninformed actions, and does not 
address intentional acts. Another commenter states that if the FAA is 
going beyond its statutory authority and being inconsistent in 
application of requirements without

[[Page 4096]]

providing justification, the commenter would view the proposed rule as 
arbitrary rulemaking.
    The FAA does not concur that the AD should be withdrawn. The 
issuance of this AD is based on the finding that an unsafe condition 
exists or is likely to develop in this airplane series. The FAA points 
out that an airplane's type design is approved only after the FAA makes 
a determination that it complies with all applicable part 25 (14 CFR 
part 25) airworthiness requirements. In adopting and maintaining those 
requirements, the FAA has made the determination that they establish an 
appropriate level of safety. However, actual in-service experience (as 
well as other factors, such as manufacturers' fatigue testing, etc.) 
may reveal problems in an airplane or its components that were not 
envisioned or predictable at the time of type certification. When these 
problems create an unsafe condition, this means that the intent of the 
original level of safety is no longer being achieved. When actions or 
procedures have been identified that will positively correct the unsafe 
condition and restore the airplane to its original level of safety, an 
AD is the appropriate vehicle for mandating that such actions be 
accomplished.

4. Request to Withdraw the Proposal: Proposed Installation May 
Introduce an Unsafe Condition

    Several commenters state that introduction of a beta lockout system 
will not provide any added safety benefit, and could actually cause an 
unsafe condition if the beta lockout system were to fail during 
landing. These commenters point out that failure of the lockout system 
to release may prevent the selection of propeller beta pitch angles (on 
the ground after landing) could, in fact, cause an over run, loss of 
control of the airplane during landing, or an accident. This commenter 
also states that with an ``override'' function, the flightcrew is 
required to perform an additional task to unlock the power levers so 
they can select ``Beta/Disking & Reverse.'' Another commenter states 
that installation of a mechanical lockout system would require an 
additional cockpit procedure and associated training. That commenter 
points out that such an additional cockpit procedure would contribute 
to the crew workload during the most critical phase of flight. Further, 
the commenter contends that the additional cockpit procedure could 
result in delay in placing the airplane in the desired configuration 
when required.
    The FAA does not concur that the installation of a beta lockout 
system may introduce an unsafe condition. The FAA has already required 
retrofit of a similar lockout system on three other turbopropeller-
powered airplane models. Further, several turboprop airplanes were 
designed and certified with beta lockout systems. Both the retrofit and 
the original designed lockout systems have been operating safely for 
close to ten years with no adverse landing or rollout service history. 
No change is required to the final rule as a result of these comments.

5. Request to Delay Issuance of the Final Rule

    Two commenters state that the proposed rule is premature and 
inconsistent, and that any rulemaking effort should wait until the 
Aviation Rulemaking Advisory Committee (ARAC) submits its findings and 
recommendations regarding a change to the Federal Aviation Regulations. 
One of those commenters points out that ARAC is not expected to submit 
its recommendations to the FAA until July 31, 2001. That commenter 
contends that, until changes to part 25 of the Federal Aviation 
Regulations have been accomplished, the proposal is premature, and, at 
best, shows an inconsistency by the FAA as a result of arbitrary 
rulemaking without explanation. Another commenter requests that the FAA 
delay issuance of a rule pending a detailed safety study review of the 
current design, with the objective of determining if the Bombardier 
design proposal for a beta warning horn addresses the unsafe condition.
    The FAA does not consider that delaying this action until after the 
release of the ARAC recommendation is warranted since sufficient 
technology currently exists to devise and install a beta lockout 
system. The purpose of the ARAC task is to determine whether changes to 
existing design standards are appropriate. These standards would be 
applicable only to future designs. In tasking ARAC on this subject, the 
FAA never intended that ARAC address issues relating to unsafe 
conditions found on previously certificated designs. Further, the FAA 
has determined that the warning horn is not sufficient to address the 
unsafe condition, and does not prevent moving the power lever into the 
beta range during flight.

6. Request to Revise Paragraph (b) of the Proposal

    Several commenters request that the FAA require installation of a 
beta warning horn rather than the beta lockout modification required by 
paragraph (b) of the proposal. These commenters also point out that 
Transport Canada Civil Aviation (TCCA), which is the airworthiness 
authority for Canada, did not determine that a beta lockout system was 
necessary. Those commenters question why the FAA has determined that 
installation of the beta lockout system is necessary when TCCA has not 
mandated such an installation. One commenter, the manufacturer, states 
that TCCA is planning to require mandatory installation of the beta 
warning horn, which would be substantially less expensive than 
installation of a beta lockout system, and would still provide an 
equivalent level of safety. Some commenters state that the description 
of the installation specified in paragraph (b) of the proposal is not 
sufficient to provide actual guidelines for the development of a beta 
lockout system. However, another commenter states that paragraph (b) of 
the proposal limits how operators can comply with the requirements.
    Another commenter requests that specific training for prohibiting 
beta during in-flight be required instead of the beta lockout system. 
Additionally, another commenter states that the service experience of 
the Model DHC-8 series airplane does not distinguish itself in 
comparison to other airplane models considering the fact that crews of 
other types of airplanes could intentionally position the power lever 
in the beta range.
    Other commenters state that a beta lockout system still wouldn't 
preclude intentional use of beta during flight because of the override 
function. The manufacturer states that the proposal implies that 
installation of a beta lockout system would preclude the pilot from 
being able to position the power lever below flight idle during flight. 
However, the manufacturer points out that with an override function, 
intentional positioning of the power levers below the flight idle stop 
during flight cannot be prevented. The manufacturer concludes, 
therefore, that the declared unsafe condition cannot be eliminated by 
the installation of a beta lockout system with an override function. 
The manufacturer asserts that, if it can be concluded that intentional 
positioning of power levers below flight idle stop during flight can 
only be deterred, the beta warning horn provides such deterrence. The 
manufacturer states that a beta warning horn provides a loud, easily 
identifiable aural warning, which would ``sound'' with any movement of 
the power levers

[[Page 4097]]

below the flight idle stop. The manufacturer further notes that TCCA 
has accepted the beta warning horn modification as an enhanced level of 
safety.
    The FAA does not concur with the requests to revise the requirement 
specified in paragraph (b) of the final rule. The FAA acknowledges that 
additional airplane flight manual limitations and additional pilot 
training have enhanced the operational safety of the airplane. However, 
those actions have not proven to solve the long-term problem involving 
unsafe operation of other turbopropeller-powered airplanes with a 
similar throttle quadrant design and service histories involving unsafe 
operation. Despite the addition of those actions, reports of beta 
during flight continued.
    Further, the FAA does not concur with the commenters' requests to 
require a beta warning horn in lieu of a beta lockout system. The FAA 
points out that it appears that certain actions taken by the flightcrew 
are reflexive, and, as such, the action of placing the power levers 
below flight idle during flight may not always be interrupted by the 
horn. Additional data indicate that if beta operation is attempted with 
a warning horn as the only safety system, it is possible that in the 
time it takes for the flightcrew to react and return the power levers 
to the flight range, an overspeed of the propeller could occur that 
might cause engine damage or failure, and consequent reduced 
controllability of the airplane. Further, the beta horn (even though 
distinctive) may be accompanied by an airplane overspeed warning horn, 
along with other warnings, which may be confusing to the flightcrew. 
The FAA points out that, in at least one previous accident caused by 
inflight beta uses on another turbpropeller-powered airplane, the pilot 
attempted to decelerate the airplane from an overspeed condition 
(airplane speed was initially above Vmo). In that case, the airspeed 
aural warning was already sounding at the time the inflight beta event 
occurred. The FAA notes that many transport category airplanes powered 
by turbopropeller engines are operated at or near Vmo during descent in 
order to maintain adequate Air Traffic Control (ATC) separation from 
the faster flying turbojet-powered airplanes. Therefore, the FAA 
considers that use of a beta warning horn could be preceded or 
accompanied by an airplane overspeed aural warning, and could result in 
confusion to the flightcrew. Although the FAA acknowledges that a beta 
warning horn should deter the pilot from using beta in flight, the horn 
does not physically keep the power levers from being placed in the beta 
mode during flight. As explained previously, several turbopropeller-
powered airplanes were designed and certified with beta lockout 
systems, and the FAA has required retrofit of a similar lockout system 
on three other turbopropeller-powered airplane models. Both the 
original design lockout systems and the retrofit have been operating 
safely for close to ten years with acceptable landing or rollout 
service history.
    In response to commenters that questioned why the FAA is requiring 
installation of a beta lockout system and TCCA has not, the FAA notes 
that, while the United States and Canada observe the provisions of the 
bilateral airworthiness agreement, it remains the responsibility of the 
FAA to monitor and maintain the continuing airworthiness of U.S-type 
certificated and -registered airplanes. The bilateral airworthiness 
agreement does not restrict the FAA from issuing AD's based upon its 
own finding of an unsafe condition, regardless of the decision relative 
to the same subject made by another airworthiness authority. The FAA 
has examined the reports of operation of the airplane with the power 
levers positioned below the flight idle stop during flight on Model 
DHC-8 series airplanes, has examined other available data, and has 
determined that an unsafe condition exists. Therefore, the FAA finds 
that AD action is necessary for airplanes of this type design that are 
certificated for operation in the United States.
    In reponse to the commenter's statement that paragraph (b) of the 
proposed rule limits the ways operators can comply with the 
requirements, the FAA points out that the language specified in that 
paragraph is purposefully general in nature to allow for some 
flexibility by the operators in complying with the requirements of that 
paragraph. Further, the FAA also points out that paragraph (d) of the 
final rule also contains a provision for operators to request approval 
of an alternative method of compliance.

7. Requests to Revise Paragraph (c) of the Proposal

    One commenter requests that the proposed allowance for Minimum 
Master Equipment List (MMEL) relief of two days, as specified in 
paragraph (c) of the proposal, be extended to three days. Another 
commenter, the manufacturer, states that, where a legitimate system 
failure has necessitated the use of the override system, operators 
should not be penalized with a mandatory maintenance action in order to 
dispatch the airplane. The manufacturer considers a lockout system to 
be a secondary non-essential system to the existing design, and, 
therefore, dispatching the airplane with a failed lockout system for a 
limited time would not jeopardize the safety of the airplane. The 
manufacturer further states that if a pilot chooses to use the override 
system just prior to touchdown during inclement weather (e.g., low 
visibility, contaminated runway), those conditions could be considered 
emergency situations. Use of an override system in such an emergency 
should not require maintenance action to return the airplane to 
dispatch configuration. For those reasons, the manufacturer requests 
that the proposed MMEL relief of two days be extended in accordance 
with criteria to be identified in the DHC-8 MMEL.
    The FAA concurs that the MMEL relief specified in paragraph (c) of 
the proposal may be extended to three flight days. However, although 
use of the override system may be made available as a means to gain 
additional stopping performance in the event of a failed beta lockout 
system, the FAA does not consider low visibility or contaminated runway 
scenarios to constitute an emergency. Further, the override function is 
used only when a system failure or potentially inadequate ground/air 
logic is indicated while the airplane is on the ground. The FAA has 
determined that in those situations a maintenance action must be taken.

8. Request to Require Only the Placard Installation

    One commenter contends that the only action that the FAA should 
require is the installation of a placard. The commenter asserts that 
adding the placard, in combination with the current pilot training 
curriculum, provides an adequate level of safety. The commenter further 
points out that only a placard is necessary for many other airplane 
models.
    The FAA does not concur that installation of the placard should be 
the only requirement of this AD. The FAA has determined that long-term 
continued operational safety will be better assured by design changes 
to remove the source of the problem, rather than by reliance upon 
visual cues such as placards. Such visual cues may not be providing the 
degree of safety assurance necessary for certain transport airplanes. 
This, coupled with a better understanding of the human factors 
associated with reliance upon visual cues, has led the FAA to consider 
placing less emphasis on such visual

[[Page 4098]]

cues and more emphasis on design improvements. The required 
installation of a beta lockout system is consistent with these 
considerations.
    The FAA acknowledges that installing a placard is the only 
requirement for some transport airplanes. Those airplanes, however, do 
not have the same service experience as Model DHC-8 series airplanes. 
As explained in Comment 6, the FAA has required the installation of a 
beta lockout system on other airplane models that have similar service 
experiences to those of Model DHC-8 series airplanes.

9. Request to Extend the Compliance Time

    One commenter, the manufacturer, requests that the compliance time 
for the installation of the beta lockout system be revised from one 
year to 2\1/2\ years. The manufacturer explains that a beta lockout 
design could be available within one year of being mandated, but 
cautions that a compliance time of 18 months after the design approval 
is necessary.
    Two other commenters request that the compliance time be changed to 
two years to allow time for design approval and actual installation. 
One other commenter states that one year is not enough time, but does 
not suggest an alternative compliance time.
    The FAA concurs that the compliance time to install the beta 
lockout system may be extended somewhat. The FAA has taken into 
consideration the complexity of accomplishing the installation of a 
beta lockout system and the time that will be needed to develop and 
approve a service bulletin, and has concluded that a two-year 
compliance time to install the beta lockout system may be established 
without adversely affecting safety. Paragraph (b) of the final rule has 
been revised accordingly.

10. Requests to Revise the Cost Estimate

    One commenter, the manufacturer, considers the cost estimate 
provided in the proposal to be significantly lower than actual costs. 
The manufacturer states that it has information indicating that the 
lockout implementation on another airplane model is estimated at an 
average of $24,000 per airplane ($12,000 for parts and $12,000 for 
labor). The manufacturer points out that the proposal does not account 
for the potential loss of revenue incurred by airplane downtime for 
incorporation of the change. The manufacturer is concerned that the 
lower cost estimate of $17,800 in the proposal may be misleading to 
operators.
    One commenter considers that the requirements of the proposal go 
beyond the current requirements for continued airworthiness; therefore, 
the costs that were disregarded in the proposal as necessary for 
``maintaining a safe airplane'' should be attributed solely as a direct 
result of the AD and should be addressed as such. Another commenter 
requests an explanation as to why a complete cost-benefit analysis is 
unnecessary and redundant. That same commenter requests that the FAA 
provide a cost-benefit analysis before a determination is made to 
require actions that may be unnecessary for an airplane that is already 
safe.
    Based on information provided by the manufacturer, the FAA concurs 
that the estimated cost for the installation of the beta lockout system 
should be adjusted, and has revised the final rule accordingly. 
However, the FAA does not concur that a cost-benefit analysis should be 
accomplished for this AD. As stated in the proposal, as a matter of 
law, in order to be airworthy, an aircraft must conform to its type 
design and be in a condition for safe operation. The type design is 
approved only after the FAA makes a determination that it complies with 
all applicable airworthiness requirements. In adopting and maintaining 
those requirements, the FAA has already made the determination that 
they establish a level of safety that is cost-beneficial. When the FAA, 
as in this AD, makes a finding of an unsafe condition, this means that 
the original cost-beneficial level of safety is no longer being 
achieved and that the actions are necessary to restore that level of 
safety. Because this level of safety has already been determined to be 
cost-beneficial, a full cost-benefit analysis for this AD would be 
redundant and unnecessary.

11. Request to Clarify Intent of the Proposed Rule

    Several commenters request that an accurate description of the 
unsafe condition be provided. Other commenters request clarification as 
to whether the FAA is trying to prevent an unsafe condition that could 
be caused by unintentional pilot actions or by intentional pilot 
actions.
    The FAA considers that an adequate description of the unsafe 
condition has already been presented in the Notice of Proposed 
Rulemaking (NPRM). The FAA has determined that operation of the 
airplane with power levers positioned below the flight idle stop during 
flight could result in engine overspeed, possible engine damage or 
failure, and consequent reduced controllability of the airplane. Since 
the FAA has received reports of those types of incidents occurring on 
Model DHC-8 series airplanes, the FAA has determined that such an 
unsafe condition exists in those models.
    Regardless of whether in-flight operation in beta resulted from 
intentional or unintentional pilot actions, the purpose of this AD is 
to prevent such operation. The FAA considers a requirement to install 
beta lockout to be the most effective means to achieve that objective.

12. Request to Ensure Consistent Requirements

    One commenter points out that the design of the power lever system 
on Model DHC-8 series airplanes is different than that of other 
turbopropeller-powered airplanes that are addressed by AD's similar to 
the proposal. Several commenters assert that there seems to be 
different requirements for certain similar airplanes and similar 
requirements for different airplanes. The commenters request that the 
FAA ``level the playing field'' to ensure requirements are consistent 
for all airplane models.
    The FAA acknowledges that there are different requirements for 
certain airplane models. As discussed previously, the requirements for 
different airplanes are based on certain aspects of design and service 
history of each different airplane model. Therefore, the FAA considers 
that the ``playing field is level'' in that the basic requirements for 
airplanes with similar design and service histories are equivalent.

13. Request for a Public Meeting

    One commenter requests that a public meeting be held to discuss the 
proposed rule. The commenter states that the proposed beta lockout 
system will not improve safety. The commenter contends that since the 
manufacturer, operators, and TCCA do not support the proposal, a public 
meeting should be held to determine the most appropriate action.
    The FAA does not concur that a public meeting is necessary to 
discuss the final rule. A Notice of Proposed Public Meeting was 
published in the Federal Register, and that meeting took place on June 
11 and 12, 1996. Draft design criteria that the FAA was considering for 
use in evaluating a beta lockout system were included in that notice. 
The public meeting was held for the purpose of soliciting and reviewing 
information from the public on what type of FAA action would be 
appropriate to prevent future occurrences of inflight beta operation on 
all turbopropeller-powered airplanes. Further, a 90-day comment period 
was

[[Page 4099]]

specified in the NPRM to allow an adequate period of time for 
commenters to respond. The fact that the final rule has been revised in 
response to certain information supplied by the commenters demonstrates 
the success of this process. For those issues on which commenters 
continue to disagree with the FAA's conclusions, given the extensive 
public participation to date, it is unlikely that yet another public 
meeting would resolve the issues. Therefore, further delay of this AD 
is inappropriate.

Conclusion

    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.

Cost Impact

    The FAA estimates that 185 de Havilland Model DHC-8-100, and -200, 
and -300 series airplanes of U.S. registry will be affected by this AD, 
that it will take approximately 1 work hour per airplane to accomplish 
the installation of the placard, and that the average labor rate is $60 
per work hour. Based on these figures, the cost impact of the placard 
installation on U.S. operators is estimated to be $11,100, or $60 per 
airplane.
    Since the manufacturer has not yet developed a specific system 
commensurate with the requirements of this AD, the FAA is unable to 
provide specific information as to the number of work hours or cost of 
parts that will be required to accomplish the installation. However, 
based on similar installations of such systems accomplished previously 
on other airplane models, the FAA can reasonably estimate that 
approximately 200 work hours per airplane will be necessary to 
accomplish the system installation. The FAA also estimates that 
required parts will cost approximately $12,000 per airplane. Based on 
these figures, the cost impact of the required system installation on 
U.S. operators is estimated to be $4,440,000, or $24,000 per airplane.
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the requirements of this 
AD action, and that no operator would accomplish those actions in the 
future if this AD were not adopted.

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 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 location provided under the caption 
ADDRESSES.

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 the following new 
airworthiness directive:

2000-02-13 de Havilland: Amendment 39-11531. Docket 98-NM-179-AD.
    Applicability: All Model DHC-8-100, -200, and -300 series 
airplanes, certificated in any category.

    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 (d) 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, unless accomplished 
previously.
    To prevent positioning of the power levers below the flight idle 
stop during flight, which could cause engine overspeed, possible 
engine damage or failure, and consequent reduced controllability of 
the airplane, accomplish the following:
    (a) Within 30 days after the effective date of this AD, install 
a placard in a prominent location on the instrument panel of the 
cockpit that states: ``Positioning of the power levers below the 
flight idle stop during flight is prohibited. Such positioning may 
lead to loss of airplane control, or may result in an engine 
overspeed condition and consequent loss of engine power.''
    (b) Within 2 years after the effective date of this AD, install 
a system that would prevent positioning the power levers below the 
flight idle stop during flight, in accordance with a method approved 
by the Manager, New York Aircraft Certification Office (ACO), FAA, 
Engine and Propeller Directorate. Following accomplishment of that 
installation, the placard required by paragraph (a) of this AD may 
be removed.
    (c) In the event that the system required by paragraph (b) of 
this AD malfunctions, or if the use of an override (if installed) is 
necessary, the airplane may be operated for three days to a location 
where required maintenance/repair can be performed, provided the 
system required by paragraph (b) of this AD has been properly 
deactivated and placarded for flightcrew awareness, in accordance 
with the FAA-approved Master Minimum Equipment List (MMEL).
    (d) 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 ACO. Operators shall 
submit their requests through an appropriate FAA Principal 
Maintenance Inspector, who may add comments and then send it to the 
Manager, New York ACO.

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


    (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) This amendment becomes effective on March 1, 2000.

    Issued in Renton, Washington, on January 20, 2000.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-1772 Filed 1-21-00; 11:20 am]
BILLING CODE 4910-13-P