[Federal Register Volume 60, Number 197 (Thursday, October 12, 1995)]
[Proposed Rules]
[Pages 53150-53152]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-25226]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 95-SW-30-AD]
Airworthiness Directives; Robinson Helicopter Company Model R44
Helicopters
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This document proposes the supersedure of an existing
airworthiness directive (AD), applicable to Robinson Helicopter Company
(Robinson) Model R44 helicopters, that currently requires revisions to
the Limitations section, the Normal Procedures section, and the
Emergency Procedures section of the R44 Rotorcraft Flight Manual,
revised September 6, 1994. These revisions limit operations in high
winds and turbulence; provide information about main rotor (M/R) stall
and mast bumping; and, provide recommendations for avoiding these
situations. Additionally, emergency procedures are provided for use
should certain conditions be encountered. This action would require
similar revisions to the Limitations, Normal Procedures and Emergency
Procedures sections required by the existing AD, and would require a
revision to the Limitations section to prohibit pilots without a
certain level of experience and training from operating in the flight
conditions specified by this AD. This proposal is prompted by
indications that pilots who possess a certain level of experience and
training are more able to recognize and react to the adverse
meteorological conditions specified in the AD. The actions specified by
the proposed AD are intended to prevent M/R stall or mast bumping,
which could result in the M/R blades contacting the fuselage causing
failure of the M/R system and subsequent loss of control of the
helicopter.
DATES: Comments must be received by October 27, 1995.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Office of the Assistant Chief Counsel, Attention:
Rules Docket No. 95-SW-30-AD, 2601 Meacham Blvd, Room 663, Fort Worth,
Texas 76137. Comments may be inspected at this location between 9:00
a.m. and 3:00 p.m., Monday through Friday, except Federal holidays.
The Special Federal Aviation Regulation (SFAR) referenced in the
proposed rule may be obtained from the FAA, Rotorcraft Standards Staff,
2601 Meacham Blvd., Fort Worth, Texas 76137. This information may be
examined at the FAA, Office of the Assistant Chief Counsel, 2601
Meacham Blvd., Room 663, Forth Worth, Texas.
FOR FURTHER INFORMATION CONTACT:
Mr. Scott Horn, Aerospace Engineer, FAA, Rotorcraft Directorate,
Rotorcraft Standards Staff, Southwest Region, 2601 Meacham Blvd., Fort
Worth, Texas 76137, telephone (817) 222-5125, fax (817) 222-5961.
SUPPLEMENTARY INFORMATION:
Comments Invited
Interested persons are invited to participate in the making of the
proposed rule by submitting such written data, views, or arguments as
they may desire. Communications should identify the Rules Docket number
and be submitted in triplicate to the address specified above. All
communications received on or before the closing date for comments,
specified above, will be considered before taking action on the
proposed rule. The proposals contained in this notice may be changed in
light of the comments received.
Comments are specifically invited on the overall regulatory,
economic, environmental, and energy aspects of the proposed rule. All
comments submitted will be available, both before and after the closing
date for comments, in the Rules Docket for examination by interested
persons. A report summarizing each FAA-public contact
[[Page 53151]]
concerned with the substance of this proposal will be filed in the
Rules Docket.
Commenters wishing the FAA to acknowledge receipt of their comments
submitted in response to this notice must submit a self-addressed,
stamped postcard on which the following statement is made: ``Comments
to Docket No. 95-SW-30-Ad.'' The postcard will be date stamped and
returned to the commenter.
Availability of NPRMs
Any Person may obtain a copy of this NPRM by submitting a request
to the FAA, Office of the Assistant Chief Counsel, ATTENTION: Docket
No. 95-SW-30-AD, 2601 Meacham Blvd, Room 663, Fort Worth, Texas 76137.
Discussion
On February 23, 1995, the FAA issued AD 95-04-13, Amendment 39-9165
(60 FR 11611, March 2, 1995), which superseded Priority Letter AD 95-
02-04, issued January 12, 1995, to require revisions to the Limitations
section, the Normal Procedures section, and the Emergency Procedures
section of the R44 Rotorcraft Flight Manual, revised September 6, 1994.
These revisions limit operations in high winds and turbulence; provide
information about M/R stalls and mast bumping; and provide
recommendations for avoiding these situations. Additionally, emergency
procedures are provided for use should certain conditions be
encountered. That action was prompted by two Model R44 accidents since
April 1994 involving M/R blades contacting the helicopter's fuselage.
M/R stall and mast bumping may have caused these M/R blade contacts
with the fuselage. Both of these accidents resulted in fatalities.
Limited pilot experience in rotorcraft has been identified as common to
these accidents. High winds and turbulence were also noted in both of
the accidents. Airspeed and low rotor RPM could also be influencing
factors in these incidents of M/R blades contacting the fuselage.
Flight in strong or gusty winds or areas of moderate, severe, or
extreme turbulence can degrade the helicopter handling qualities,
thereby creating an unsafe condition for those pilots with a level of
experience of less than 200 hours of helicopter time, of which 50 hours
or less is in the Model R44 helicopter. The requirements of the
existing AD are intended to prevent M/R stall or mast bumping, which
could result in the M/R blades contacting the fuselage causing failure
of the M/R system and subsequent loss of control of the helicopter.
Since the issuance of that AD, the FAA has continued to analyze the
accident data and develop new information. The FAA conducted a Flight
Standardization Board (FSB); issued a SFAR; and, in conjunction with
the manufacturer, developed an awareness training program. The FSB
issued a report that specified FAA minimum training, evaluation, and
currency requirements applicable to persons operating the Robinson
Model R44 helicopters under Federal Aviation Regulation (FAR) Part 91.
The FSB determined a need for training designed to enhance the pilot's
awareness of the unique characteristics associated with operating the
Model R44 helicopter. SFAR No. 73, issued February 27, 1995, identifies
pilots that have 200 flight hours in helicopters, including at least 50
hours in the Model R44 helicopter, as having the experience necessary
to recognize, as well as react to, situations that can cause M/R blade
contact with the helicopter's fuselage. The SFAR also establishes
criteria for flight instructors and requires that all individuals
operating the R44 have awareness training and meet Part 61 flight
review requirements. The awareness training described in the SFAR
provides information on flight in turbulent conditions and the effects
of reduced ``G'' operations. All individuals operating the Model R44
helicopter were required to have had this training prior to April 26,
1995. The accident data analyzed by the FAA indicates that, where
turbulent conditions were listed as a causal factor, the pilots thought
to be at the controls did not meet the SFAR experience requirement of
200 flight hours in helicopters, with at least 50 hours in the Model
R44 helicopter. These data, when combined with the SFAR pilot
experience and awareness training requirements, indicate that relief
for pilots who meet these requirements is appropriate. Additionally,
the references to wind shear in the existing AD have been deleted
because the equipment necessary to recognize wind shear is not
available and the limitation for turbulence applies to wind shear
situations.
Since an unsafe condition has been identified that is likely to
exist or develop on other Robinson Model R44 helicopters of the same
type design, the proposed AD would supersede AD 95-04-13 to require
revisions to the Normal Procedures, Emergency Procedures, and
Limitations sections of the R44 Rotorcraft Flight Manual. The revision
to the Limitations section states that the limitations of paragraph a.
of that section are to be observed when the pilot manipulating the
controls has not taken the prescribed awareness training specified in
SFAR 73, and has not logged a total of 200 hours of helicopter flight
time, at least 50 of which must be in the Model R44 helicopter. The
paragraph b. revisions to the Limitations section are to be observed by
all pilots.
The FAA estimates that three helicopters of U.S. registry would be
affected by this proposed AD, that it would take approximately one-half
work hour per helicopter to accomplish the proposed actions, and that
the average labor rate is $60 per work hour. Based on these figures,
the total cost impact of the proposed AD on U.S. operators is estimated
to be $90.
The regulations proposed herein would 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
proposal would not have sufficient federalism implications to warrant
the preparation of a Federal Assessment.
For the reasons discussed above, I certify that this proposed
regulation (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) if promulgated, 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 draft
regulatory 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 captain ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Safety.
The Proposed Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration proposes to amend
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), 40101, 40113, 44701.
[[Page 53152]]
Sec. 39.13 [Amended]
2. Section 39.13 is amended by removing Amendment 39-9165, and by
adding a new airworthiness directive (AD), to read as follows:
Robinson Helicopter Company: Docket No. 95-SW-30-AD. Supersedes AD
95-04-13, Amendment 39-9165.
Applicability: Model R44 helicopters, certificated in any
category.
Note 1: This AD applies to each helicopter 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 helicopters that have been modified,
altered, or repaired so that the performance of the requirements of
this AD is affected, the owner/operator must use the authority
provided in paragraph (b) to request approval from the FAA. This
approval may address either no action, if the current configuration
eliminates the unsafe condition, or different actions necessary to
address the unsafe condition described in this AD. Such a request
should include an assessment of the effect of the changed
configuration on the unsafe condition addressed by this AD. In no
case does the presence of any modification, alteration, or repair
remove any helicopter from the applicability of this AD.
Compliance: Required before further flight, unless accomplished
previously.
Note 2: Regardless of the experience level of the pilot
manipulating the controls or the amount or quality of the awareness
training received by the pilot manipulating the controls, these
changes to the flight manual are in no way intended to authorize
flight in any condition(s) or under any circumstance(s) that are
otherwise contrary to other Federal Aviation Regulations.
To prevent main rotor (M/R) stall or mast bumping, which could
result in the M/R blades contacting the fuselage causing failure of
the M/R system, and subsequent loss of control of the helicopter,
accomplish the following:
(a) Insert the following information into the Model R44
Rotorcraft Flight Manual. Compliance with the Limitations section is
mandatory. The Normal Procedures and Emergency Procedures sections
are informational.
Limitations Section
The following limitations (1-3) are to be observed unless the
pilot manipulating the controls has logged 200 or more flight hours
in helicopters, at least 50 of which must be in the RHC Model R44
helicopter, and has completed the awareness training specified in
Special Federal Aviation Regulations (SFAR) No. 73, issued February
27, 1995.
(1) Flight when surface winds exceed 25 knots, including gusts,
is prohibited.
(2) Flight when surface wind gust spreads exceed 15 knots is
prohibited.
(3) Continued flight in moderate, severe, or extreme turbulence
is prohibited.
Adjust forward airspeed to between 60 knots indicated airspeed
(KIAS) and 0.7 Vne, but no lower than 60 KIAS, upon inadvertently
encountering moderate, severe, or extreme turbulence.
Note: Moderate turbulence is turbulence that causes: (1) Changes
in altitude or attitude; (2) variations in indicated airspeed; and
(3) aircraft occupants to feel definite strains against seat belts.
Normal Procedures Section
Note
Until the FAA completes its research into the conditions and
aircraft characteristics that lead to main rotor blade/fuselage
contact accidents, and corrective type design changes and operating
limitations are identified, Model R44 pilots are strongly urged to
become familiar with the following information and comply with these
recommended procedures.
Main Rotor Stall: Many factors may contribute to main rotor
stall and pilots should be familiar with them. Any flight condition
that creates excessive angle of attack on the main rotor blades can
produce a stall. Low main rotor RPM, aggressive maneuvering, high
collective angle (often the result of high-density altitude, over-
pitching [exceeding power available] during climb, or high forward
airspeed) and slow response to the low main rotor RPM warning horn
and light may result in main rotor stall. The effect of these
conditions can be amplified in turbulence. Main rotor stall can
ultimately result in contact between the main rotor and airframe.
Additional information on main rotor stall is provided in the
Robinson Helicopter Company Safety Notices SN-10, SN-15, SN-20, SN-
24, SN-27, and SN-29.
Mast Bumping: Mast bumping may occur with a teetering rotor
system when excessive main rotor flapping results from low ``G''
(load factor below 1.0) or abrupt control input. A low ``G'' flight
condition can result from an abrupt cyclic pushover in forward
flight. High forward airspeed, turbulence, and excessive sideslip
can accentuate the adverse effects of these control movements. The
excessive flapping results in the main rotor hub assembly striking
the main rotor mast with subsequent main rotor system separation
from the helicopter.
To avoid these conditions, pilots are strongly urged to follow
these recommendations:
(1) Maintain cruise airspeeds greater than 60 KIAS and less than
0.9 Vne.
(2) Use maximum ``power-on'' RPM at all times during powered
flight.
(3) Avoid sideslip during flight. Maintain in-trim flight at all
times.
(4) Avoid large, rapid forward cyclic inputs in forward flight,
and abrupt control inputs in turbulence.
Emergency Procedures Section
(1) Right Roll in Low ``G'' Condition
Gradually apply aft cyclic to restore positive ``G'' forces and
main rotor thrust. Do not apply lateral cyclic until positive ``G''
forces have been established.
(2) Uncommanded Pitch, Roll, or Yaw Resulting From Flight in Turbulence
Gradually apply controls to maintain rotor RPM, positive ``G''
forces, and to eliminate sideslip. Minimize cyclic control inputs in
turbulence; do not overcontrol.
(3) Inadvertent Encounter With Moderate, Severe, or Extreme Turbulence.
If the area of turbulence is isolated, depart the area;
otherwise, land the helicopter as soon as practical.
(b) An alternative method of compliance or adjustment of the
compliance time that provides an acceptable level of safety may be
used when approved by the Manager, Rotorcraft Standards Staff,
Rotorcraft Directorate, FAA. Operators shall submit their requests
through an FAA Principal Maintenance Inspector, who may concur or
comment and then send it to the Manager, Rotorcraft Standards Staff.
Note 3: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Rotorcraft Standards Staff.
(c) Special flight permits, pursuant to sections 21.197 and
21.199 of the Federal Aviation Regulations (14 CFR 21.197 and
21.199), will not be issued.
Issued in Fort Worth, Texas, on September 29, 1995.
Daniel P. Salvano,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 95-25226 Filed 10-11-95; 8:45 am]
BILLING CODE 4910-13-M
