[Federal Register Volume 63, Number 192 (Monday, October 5, 1998)]
[Rules and Regulations]
[Pages 53278-53279]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-26603]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Parts 23, 25 and 33
[Docket No. 28652; Amendment Nos. 23-53, 25-95, and 33-19]
RIN 2120-AF75
Airworthiness Standards; Rain and Hail Ingestion Standards;
Correction
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; correction.
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SUMMARY: This document corrects a final rule that was published in the
Federal Register on March 26, 1998 (63 FR 14794). The final rule
addressed engine power loss and instability phenomena attributed to
operation in extreme rain or hail. Also, the final rule generally
harmonized the Federal Aviation Administration and Joint Aviation
Authorities rain and hail ingestion standards.
DATES: Effective October 5, 1998.
FOR FURTHER INFORMATION CONTACT: John Fisher, Burlington, Massachusetts
01803-5229; telephone (781) 238-7149; fax (781) 238-7199.
SUPPLEMENTARY INFORMATION: The Airworthiness Standards final rule on
Rain and Hail Ingestion Standards, Docket No. 28652 was published in
the Federal Register on March 26, 1998 (63 FR 14794). Under
``Discussion of Comments,'' there is an incorrect phrase, and under
Sec. 33.77 of the rule, the foreign object ingestion conditions table
provides either misplaced or incorrect phrases.
1. On page 14795, under ``Discussion of Comments,'' third column,
third paragraph, nine lines down, the phrase ``Some amount of sustained
power or thrust loss is permitted following an ice ingestion test''
should be replaced with ``Some amount of sustained power or thrust loss
is permitted following testing to the new rain and hail ingestion
standards, but no power or thrust loss is permitted following an ice
ingestion test.''
2. On page 14798, third column, under Sec. 33.77(e), the ingestion
conditions table is corrected to read as follows:
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Foreign object Test quantity Speed of foreign object Engine operation Ingestion
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BIRDS:
3-ounce size.................... One for each 50 square Liftoff speed of typical Takeoff.................... In rapid sequence to
inches of inlet area, or aircraft. simulate flock encounter
in fraction thereof, up to and aimed at selected
a maximum of 16 birds. critical areas.
Three-ounce bird will pass
the inlet guide vanes into
the rotor blades.
1\1/2\-pound size............... One for the first 300 Initial climb speed of Takeoff.................... In rapid sequence to
square inches of inlet typical aircraft. simulate a flock encounter
area, if it can enter the and aimed at selected
inlet, plus one for each critical areas.
additional 600 square
inches of inlet area, or
fraction, thereof up to a
maximum of 8 birds.
4-pound size.................... One, if it can enter the Maximum climb speed of Maximum cruise............. Aimed at critical area.
inlet.. typical aircraft, if the
engine has inlet guide
vanes.
Liftoff speed typical Takeoff.................... Aimed at critical area.
aircraft, if the engine
does not have inlet guide
vanes.
ICE................................. Maximum accumulation on a Sucked in.................. Maximum cruise............. To simulate a continuous
typical inlet cowl and maximum icing encounter at
engine face resulting from 25 deg.F.
a 2-minute delay in
actuating anti-icing
system, or a slab of ice
which is comparable in
weight or thickness for
that size engine.
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Note: The term ``inlet area'' as used in this section means the engine inlet projected area at the front face of the engine. It includes the projected
area of any spinner bullet nose that is provided.
[[Page 53279]]
Issued in Washington, DC on September 30, 1998.
Donald P. Byrne,
Assistant Chief Counsel.
[FR Doc. 98-26603 Filed 10-2-98; 8:45 am]
BILLING CODE 4910-13-M
