DATE: December 23, 2005
AD #: 2005-26-53
Send to all owners and operators of Pacific Aerospace Corporation
Ltd. Model 750XL airplanes, all serial numbers, that are
certificated in any category.
What events have caused
this AD?
The Civil Aviation Authority (CAA), which is the airworthiness
authority for New Zealand, recently notified FAA that an unsafe
condition may exist on Pacific Aerospace Corporation Ltd (PAC)
Model 750XL airplanes. The CAA reports that the wings of these
airplanes may not meet the ultimate load requirements for a maximum
takeoff weight of 7,500 pounds. PAC found the condition on a
production wing during an ultimate load test. Investigation is not
complete, but indications show that some critical rivets were not
fully age-hardened. PAC has started developing a modification that
will replace the critical rivets with “AN” bolts, but
it will be some time before the modification is available.
In the interim, PAC is reducing the maximum takeoff weight from
7,500 pounds to 7,125 pounds.
The maximum takeoff weight reduction will allow the airplane to
meet the ultimate load
requirements for an airplane certificated in the Normal
Category.
What are the consequences if the condition is not
corrected?
The wing not being able to hold ultimate load could result in
wing failure and subsequent loss of control of the airplane. What
action did the CAA of New Zealand take? The CAA issued emergency
New Zealand AD Number DCA/750XL/7, dated December 22, 2005, to
ensure the continued airworthiness of these airplanes in New
Zealand.
Did the CAA of New Zealand inform the United States
under the bilateral airworthiness agreement?
These PAC Model 750XL airplanes are manufactured in New Zealand
and are typecertificated for operation in the United States under
the provisions of section 21.29 of the Federal Aviation Regulations
(14 CFR 21.29) and the applicable bilateral airworthiness
agreement. Under this bilateral airworthiness agreement, the CAA of
New Zealand has kept us informed of the situation described
above.
What has FAA decided?
After careful review of all available information related to the
subject presented above, we have identified an unsafe condition
that is likely to exist or develop on other products of this same
type design. For this reason, FAA has determined that:
- the maximum takeoff weight should be reduced from 7,500 pounds
to 7,125 pounds on type design PAC 750XL airplanes; and
- AD action should be taken to allow wing ultimate load
requirements to be met, which if not met, could result in wing
failure and subsequent loss of control of the airplane.
What does this AD require?
This AD requires you to insert the following into the
Limitations Section of the Airplane Flight Manual (AFM): "The
maximum takeoff weight is reduced from 7,500 pounds to 7,125
pounds." In preparation of this rule, we contacted type clubs and
aircraft operators to obtain technical information and information
on operational and economic impacts. We have included, in the
rulemaking docket, a discussion of information that may have
influenced this action.
Presentation of the Actual AD
This rule is issued under 49 U.S.C. Section 44701 (formerly
section 601 of the Federal Aviation Act of 1958), pursuant to the
authority delegated to me by the Administrator, and is effective
immediately upon receipt of this action. 2005-26-53 PACIFIC
AEROSPACE CORPORATION LTD.: Directorate Identifier
2005-CE-54-AD.
When Does This AD Become Effective?
(a) This emergency AD becomes effective upon receipt.
Are Any Other ADs Affected By This Action?
(b) None.
What Airplanes Are Affected by This AD?
(c) This AD affects Model 750XL, all serial numbers, that are
certificated in any category.
What is the Unsafe
Condition Presented in This AD?
(d) This AD is the result of information that the wing of these
airplanes may not meet the ultimate load requirements for a maximum
takeoff weight of 7,500 pounds. Pacific Aerospace Corporation Ltd.
found the condition on a production wing during an ultimate load
test. Investigation is not complete, but indications show that some
critical rivets were not fully age-hardened. This AD is intended to
allow wing ultimate load requirements to be met, which if not met,
could result in wing failure and subsequent 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: Insert the following information into
the Limitations Section of the Airplane Flight Manual (AFM). You
may do this by inserting a copy of this AD into the Limitations
Section of the AFM. “The maximum takeoff weight is reduced
from 7,500 pounds to 7,125 pounds.”
- Compliance: Prior to further flight after
receipt of this emergency AD.
- Procedures: The owner/operator holding at
least a private pilot certificate as authorized by section 43.7 of
the Federal Aviation Regulations (14 CFR 43.7) may do the flight
manual changes requirement of this AD. Make an entry in the
aircraft records showing compliance with this portion of the AD
following section 43.9 of the Federal Aviation Regulations (14 CFR
43.9).
May I Request an Alternative Method of
Compliance?
(f) The Manager, Standards Office, Small Airplane Directorate,
FAA, has the authority to approve alternative methods of compliance
for this AD, if requested using the procedures found in 14 CFR
39.19. For information on any already approved alternative methods
of compliance, contact Karl Schletzbaum, Aerospace Engineer, FAA,
Small Airplane Directorate, 901 Locust, Room 301, Kansas City,
Missouri 64106; telephone: (816) 329-4146; facsimile: (816)
329-4090.
Is There Other Information That Relates to This
Subject?
(g) CAA Airworthiness Directive DCA/750XL/7, dated December 22,
2005, also addresses
the subject of this AD.