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Airworthiness Directive packet

AD 98-09-14

Airworthiness Directives; Diamond Aircraft Industries Models HK 36 TTS and HK 36 TTC Sailplanes

1 · Quick read — prepared by AircraftDirectives

Our plain-language summary — not the regulation

Requires inspecting the engine turbocharger oil-pressure line for the correct banjo bolt.

AD number
98-09-14
Federal Register document
98-11008
Citation
63 FR 23200
Amendment
39-10495
Docket
Docket No. 97-CE-132-AD
Action
Final rule.
Published
1998-04-28
Effective
1998-06-14
Effective (as stated in the rule)
Effective June 14, 1998.
Issued by
Transportation Department, Federal Aviation Administration
Regulation
14 CFR 39
Applies to (in our index)
Diamond HK 36 Dimona

2 · Official Federal Register document — government source, verbatim

Reproduced unedited from the Federal Register
[Federal Register Volume 63, Number 81 (Tuesday, April 28, 1998)]
[Rules and Regulations]
[Pages 23200-23201]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-11008]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-CE-132-AD; Amendment 39-10495; AD 98-09-14]
RIN 2120-AA64


Airworthiness Directives; Diamond Aircraft Industries Models HK 
36 TTS and HK 36 TTC Sailplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
applies to certain Diamond Aircraft Industries (Diamond) Models HK 36 
TTS and HK 36 TTC sailplanes. This AD requires inspecting the engine 
turbocharger oil-pressure line for the correct banjo bolt. The correct 
banjo bolt will have a valve seat, instead of a built-in orifice. If 
the banjo bolt does not have a valve seat, then this action will 
require replacing the banjo bolt with one that has a valve seat, and 
repairing or replacing the turbocharger. This AD is the result of 
mandatory continuing airworthiness information (MCAI) issued by the 
airworthiness authority for Austria. The actions specified by this AD 
are intended to prevent possible loss of engine power, which could 
result in possible loss of control of the sailplane.

DATES: Effective June 14, 1998.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of June 14, 1998.

ADDRESSES: Service information that applies to this AD may be obtained 
from Diamond Aircraft Industries, G.m.b.H., N.A. Otto-Strabe 5, A-2700, 
Wiener Neustadt, Austria. This information may also be examined at the 
Federal Aviation Administration (FAA), Central Region, Office of the 
Regional Counsel, Attention: Rules Docket No. 97-CE-132-AD, Room 1558, 
601 E. 12th Street, Kansas City, Missouri 64106; or at the Office of 
the Federal Register, 800 North Capitol Street, NW, suite 700, 
Washington, DC.

FOR FURTHER INFORMATION CONTACT: Mr. Mike Kiesov, Aerospace Engineer, 
Small Airplane Directorate, Aircraft Certification Service, FAA, 1201 
Walnut, suite 900, Kansas City, Missouri 64106; telephone: (816) 426-
6934; facsimile: (816) 426-2169.

SUPPLEMENTARY INFORMATION:

Events Leading to the Issuance of This AD

    A proposal to amend part 39 of the Federal Aviation Regulations (14 
CFR part 39) to include an AD that would apply to certain Diamond 
Models HK 36 TTS and HK 36 TTC sailplanes that are equipped with 
Bombardier ROTAX (ROTAX) 914 F series engines, serial numbers 4,420.011 
through 4,420.058, was published in the Federal Register as a notice of 
proposed rulemaking (NPRM) on February 11, 1998 (63 FR 6882). The NPRM 
proposed to require inspecting the banjo bolt for a valve seat. If the 
banjo bolt does not have a valve seat, this AD will require replacing 
the banjo bolt, and repairing or replacing the turbocharger. 
Accomplishment of the proposed installation will be in accordance with 
Bombardier ROTAX Technical Bulletin No. 914-04, dated August, 1997.
    The NPRM was the result of mandatory continuing airworthiness 
information (MCAI) issued by the airworthiness authority for Austria.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. No comments were received on the 
proposed rule or the FAA's determination of the cost to the public.

The FAA's Determination

    After careful review of all available information related to the 
subject presented above, the FAA has determined that air safety and the 
public interest require the adoption of

[[Page 23201]]

the rule as proposed except for minor editorial corrections. The FAA 
has determined that these minor corrections will not change the meaning 
of the AD and will not add any additional burden upon the public than 
was already proposed.

Cost Impact

    The FAA estimates that 4 sailplanes in the U.S. registry will be 
affected by this AD, that it will take approximately 1 workhour per 
sailplane to accomplish this inspection, and that the average labor 
rate is approximately $60 an hour. Based on these figures, the total 
cost impact of this AD on U.S. operators is estimated to be $240 or $60 
per sailplane.

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 copy of the final evaluation prepared for this 
action is contained 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, Incorporation by 
reference, 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 
(AD) to read as follows:

98-09-14  Diamond Aircraft Industries: Amendment 39-10495; Docket 
No. 97-CE-132-AD.

    Applicability: Model HK 36 TTS and HK 36 TTC sailplanes, all 
serial numbers, certificated in any category, that are equipped with 
Bombardier ROTAX 914 F series engines, serial numbers 4,420.011 
through 4,420.058.

    Note 1: This AD applies to each sailplane 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 sailplanes 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 within the next 10 hours time-in-service 
(TIS) after the effective date of this AD, unless already 
accomplished.
    To prevent possible loss of engine power, which could result in 
possible loss of control of the sailplane, accomplish the following:
    (a) Inspect the Bombardier ROTAX engine's turbocharger oil-
pressure line for a banjo bolt with a valve seat, part number (P/N) 
941 782 (or an FAA-approved equivalent part number), in accordance 
with the Instructions section of Bombardier ROTAX Technical Bulletin 
No. 914-04, dated August, 1997.

    Note 2: An incorrect banjo bolt would have a built-in orifice, 
instead of a valve seat.

    (b) If an incorrect banjo bolt is installed, prior to further 
flight, replace the banjo bolt with one that has P/N 941 782 (or an 
FAA-approved equivalent part number), and repair or replace the 
turbocharger in accordance with the Instructions section of 
Bombardier ROTAX Technical Bulletin No. 914-04, dated August, 1997.
    (c) 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 sailplane to a location where 
the requirements of this AD can be accomplished.
    (d) An alternative method of compliance or adjustment of the 
compliance time that provides an equivalent level of safety may be 
approved by the Manager, Small Airplane Directorate, FAA, 1201 
Walnut, suite 900, Kansas City, Missouri 64106. The request shall be 
forwarded through an appropriate FAA Maintenance Inspector, who may 
add comments and then send it to the Manager, Small Airplane 
Directorate.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Small Airplane Directorate.

    (e) Questions or technical information related to Bombardier 
ROTAX Technical Bulletin No. 914-04, dated August 1997, should be 
directed to Diamond Aircraft Industries, G.m.b.H., N.A. Otto-Strabe 
5, A-2700, Wiener Neustadt, Austria. This service information may be 
examined at the FAA, Central Region, Office of the Regional Counsel, 
Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106.
    (f) The inspection and replacement required by this AD shall be 
done in accordance with Bombardier ROTAX Technical Bulletin No. 914-
04, dated August, 1997. This incorporation by reference was approved 
by the Director of the Federal Register in accordance with 5 U.S.C. 
552(a) and 1 CFR part 51. Copies may be obtained from Diamond 
Aircraft Industries, G.m.b.H., N.A. Otto-Strabe 5, A-2700, Wiener 
Neustadt, Austria. Copies may be inspected at the FAA, Central 
Region, Office of the Regional Counsel, Room 1558, 601 E. 12th 
Street, Kansas City, Missouri, or at the Office of the Federal 
Register, 800 North Capitol Street, NW, suite 700, Washington, DC.

    Note 4: The subject of this AD is addressed in Austrian AD No. 
90, undated.

    (g) This amendment becomes effective on June 14, 1998.

    Issued in Kansas City, Missouri, on April 17, 1998.
James A. Jackson,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-11008 Filed 4-27-98; 8:45 am]
BILLING CODE 4910-13-U

Sources. Section 1 is written by AircraftDirectives from the record below and is a reading aid only. Section 2 is the United States Government's own text, reproduced without edit.

Federal Register: https://www.federalregister.gov/documents/1998/04/28/98-11008/airworthiness-directives-diamond-aircraft-industries-models-hk-36-tts-and-hk-36-ttc-sailplanes

Official PDF: https://www.govinfo.gov/content/pkg/FR-1998-04-28/pdf/98-11008.pdf

Packet generated 2026-08-18 08:17 UTC.

This packet is not an airworthiness determination and not legal or maintenance advice. AircraftDirectives reproduces official records and condenses their wording for easier reading. It does not decide, certify or imply whether any aircraft, engine, appliance or part is airworthy, compliant, affected by this directive, or eligible for return to service. No inspection, approval, or determination of any kind is performed or implied by this document.

Section 1 is a reading aid, not the rule. It is our own plain-language condensation, written to help a reader find the relevant directive quickly. It is NOT a substitute for the regulation, it may omit conditions, exceptions, compliance times, alternative methods of compliance (AMOCs) and applicability limits, and it has no legal force whatsoever. Only the official text governs. Where Section 1 and Section 2 differ in any respect, Section 2 - and the official source it was retrieved from - controls absolutely.

Responsibility remains with the owner/operator. Under 14 CFR §91.403 and §91.417 the owner or operator is responsible for maintaining airworthiness and for required records; under §39.7 no person may operate a product to which an airworthiness directive applies except in accordance with that directive. Determining applicability to a specific serial number and configuration, and performing or supervising any required action, is the responsibility of the owner/operator and appropriately certificated personnel.

Accuracy and currency. Section 2 was retrieved at the time stamped above and is reproduced without edit; Federal Register material is a work of the United States Government. Directives are amended, corrected and superseded over time, and this sheet is a snapshot, not a live record - it does not update after printing. Re-check the official sources before acting on it. This packet is provided without warranty of any kind, express or implied, including fitness for a particular purpose. We do not sell parts and have no commercial interest in any action a directive may require.

AircraftDirectives · AD 98-09-14 · Section 1 is our plain-language reading aid; Section 2 is the official Federal Register text and controls where the two differ. Not an airworthiness determination — 14 CFR §91.403 / §91.417 responsibility remains with the owner/operator. Retrieved 2026-08-18 08:17 UTC.