[Federal Register: June 7, 2006 (Volume 71, Number 109)]
[Proposed Rules]
[Page 32877-32882]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr07jn06-30]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Parts 91, 121, 125, and 135
Announcement of Policy for Landing Performance Assessments After
Departure for All Turbojet Operators
AGENCY: Federal Aviation Administration, DOT.
ACTION: Advance notice of policy statement.
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SUMMARY: The following advance notice of policy and information would
provide clarification and guidance for all operators of turbojet
aircraft for establishing operators' methods of ensuring that
sufficient landing distance exists for safely making a full stop
landing with an acceptable safety margin, on the runway to be used, in
the conditions existing at the time of arrival, and with the
deceleration means and airplane configuration to be used.
FOR FURTHER INFORMATION CONTACT: Jerry Ostronic, Air Transportation
Division, AFS-200, 800 Independence Avenue, SW., Washington, DC 20591,
and Telephone (202) 267-8166.
SUPPLEMENTARY INFORMATION:
Overview
The Federal Aviation Administration (FAA) considers a 15% margin
between the expected actual (unfactored) airplane landing distance and
the landing distance available at the time of arrival as the minimum
acceptable safety margin for normal operations. Accordingly, the agency
intends to issue Operations Specification/Management Specification
(OpSpec/MSpec) C082 later this month implementing the requirements
discussed in this notice.
The FAA acknowledges that there are situations where the flightcrew
needs to know the absolute performance capability of the airplane.
These situations include emergencies or abnormal and irregular
configurations of the airplane such as engine failure or flight control
malfunctions. In these circumstances, the pilot must consider whether
it is safer to remain in the air or to land immediately and must know
the actual landing performance capability (without an added safety
[[Page 32878]]
margin) when making these evaluations. This policy is not intended to
curtail such evaluations from being made for these situations.
This policy does not apply to Land and Hold Short Operations
(LAHSO).
Definitions
The following definitions are specific to this policy and may
differ with those definitions contained in other published references.
Actual Landing Distance. The landing distance for the reported
meteorological and runway surface conditions, airplane weight, airplane
configuration, use of autoland or a Head-up Guidance System, and ground
deceleration devices planned to be used for the landing. It does not
include any safety margin (i.e., it is unfactored) and represents the
best performance the airplane is capable of for the conditions.
Airplane Ground Deceleration Devices. Any device used to aid in the
onset or rate of airplane deceleration on the ground during the landing
roll out. These would include, but not be limited to: brakes (either
manual braking or the use of autobrakes), spoilers, and thrust
reversers.
At Time of Arrival. For the purpose of this notice and related
OpSpec/MSpec means a point in time as close to the airport as possible
consistent with the ability to obtain the most current meteorological
and runway conditions considering pilot workload and traffic
surveillance, but no later than the commencement of the approach
procedures or visual approach pattern.
Braking Condition Terms. The following braking condition terms are
widely used in the aviation industry and are furnished by air traffic
controllers when available. The definitions provided below are
consistent with how these terms are used in this notice.
Good--More braking capability is available than is used in typical
deceleration on a non-limiting runway (i.e., a runway with additional
stopping distance available). However, the landing distance will be
longer than the certified (unfactored) dry runway landing distance,
even with a well executed landing and maximum effort braking.
Fair/Medium--Noticeably degraded braking conditions. Expect and
plan for a longer stopping distance such as might be expected on a
packed or compacted snow-covered runway.
Poor--Very degraded braking conditions with a potential for
hydroplaning. Expect and plan for a significantly longer stopping
distance such as might be expected on an ice-covered runway.
Nil--No braking action and poor directional control can be
expected.
Note: Conditions specified as ``nil'' are not considered safe,
therefore operations under conditions specified as such will not be
conducted. Do not attempt to operate on surfaces reported or
expected to have nil braking action.
Factored Landing Distance. The certificated landing distance
increased by the preflight planning safety margin additives.
Landing Distance Available. The length of the runway declared
available for landing. This distance may be shorter than the full
length of the runway.
Meteorological Conditions. Any meteorological condition that may
affect either the air or ground portions of the landing distance.
Examples may include wind direction and velocity, pressure altitude,
temperature, and visibility. An example of a possible effect that must
be considered includes crosswinds affecting the amount of reverse
thrust that can be used on airplanes with tail mounted engines due to
rudder blanking effects.
Reliable Braking Action Report. For the purpose of this notice and
related OpSpec/MSpec, means a braking action report submitted from a
turbojet airplane with landing performance capabilities similar to
those of the airplane being operated.
Runway Contaminant Conditions. The type and depth (if applicable)
of the substance on the runway surface, e.g., water (wet), standing
water, dry snow, wet snow, slush, ice, sanded, or chemically treated.
Runway Friction or Runway Friction Coefficient. The resistance to
movement of an object moving on the runway surface as measured by a
runway friction measuring device. The resistive force resulting from
the runway friction coefficient is the product of the runway friction
coefficient and the weight of the object.
Runway Friction Enhancing Substance. Any substance that increases
the runway friction value.
Safety Margin. The length of runway available beyond the actual
landing distance. Safety margin can be expressed in a fixed distance
increment or a percentage increase beyond the actual landing distance
required.
Unfactored Landing Distance. The certificated landing distance
without any safety margin additives.
Background
After any serious aircraft accident or incident, the FAA typically
performs an internal audit to evaluate the adequacy of current
regulations and guidance information in areas that come under scrutiny
during the course of the accident investigation. The Southwest Airlines
landing overrun accident involving a Boeing 737-700 at Chicago Midway
Airport in December 2005 initiated such an audit. The types of
information that were evaluated in addition to the regulations were FAA
orders, notices, advisory circulars, ICAO and foreign country
requirements, airplane manufacturer-developed material, independent
source material, and the current practices of air carrier operators.
This internal FAA review revealed the following issues:
(1) A survey of operators' manuals indicated that approximately
fifty percent of the operators surveyed do not have policies in place
for assessing whether sufficient landing distance exists at the time of
arrival, even when conditions (including runway, meteorological,
surface, airplane weight, airplane configuration, and planned usage of
decelerating devices.) are different and worse than those planned at
the time the flight was released.
(2) Not all operators who perform landing distance assessments at
the time of arrival have procedures that account for runway surface
conditions or reduced braking action reports.
(3) Many operators who perform landing distance assessments at the
time of arrival do not apply a safety margin to the expected actual
(unfactored) landing distance. Those that do are inconsistent in
applying an increasing safety margin as the expected actual landing
distance increased (i.e., as a percentage of the expected actual
landing distance).
(4) Some operators have developed their own contaminated runway
landing performance data or are using data developed by third party
vendors. In some cases, these data are less conservative than the
airplane manufacturer's data for the same conditions. In other cases,
an autobrake landing distance chart has been misused to generate
landing performance data for contaminated runway conditions. Also, some
operators' data have not been kept up to date with the manufacturer's
current data.
(5) Credit for the use of thrust reversers in the landing
performance data is not uniformly applied and pilots may be unaware of
these differences. In one case, the FAA found differences within the
same operator from one series of airplane to another within the same
make and model. The operator's understanding of the data with respect
[[Page 32879]]
to reverse thrust credit, and the information conveyed to pilots, were
incorrect for both series of airplanes.
(6) Airplane flight manual (AFM) landing performance data are
determined during flight-testing using flight test and analysis
criteria that are not representative of everyday operational practices.
Landing distances determined in compliance with 14 CFR part 25, section
25.125 and published in the FAA-approved airplane flight manual (AFM)
do not reflect operational landing distances (Note: some manufacturers
provide factored landing distance data that addresses operational
requirements.) Landing distances determined during certification tests
are aimed at demonstrating the shortest landing distances for a given
airplane weight with a test pilot at the controls and are established
with full awareness that operational rules for normal operations
require additional factors to be added for determining minimum
operational field lengths. Flight test and data analysis techniques for
determining landing distances can result in the use of high touchdown
sink rates (as high as 8 feet per second) and approach angles of -3.5
degrees to minimize the airborne portion of the landing distance.
Maximum manual braking, initiated as soon as possible after landing, is
used in order to minimize the braking portion of the landing distance.
Therefore, the landing distances determined under section 25.125 are
shorter than the landing distances achieved in normal operations.
(7) Wet and contaminated runway landing distance data are usually
an analytical computation using the dry, smooth, hard surface runway
data collected during certification. Therefore, the wet and
contaminated runway data may not represent performance that is achieved
in normal operations. This lack of operational landing performance
repeatability from the flight test data, along with many other
variables affecting landing distance, are taken into consideration in
the preflight landing performance calculations by requiring a
significant safety margin in excess of the certified (unfactored)
landing distance that would be required under those conditions.
However, the regulations do not specify a particular safety margin for
a landing distance assessment at the time of arrival. This safety
margin has been left largely to the operator and/or the flightcrew to
determine.
(8) Manufacturers do not provide advisory landing distance
information in a standardized manner. However, most turbojet
manufacturers make landing distance performance information available
for a range of runway or braking action conditions using various
airplane deceleration devices and settings under a variety of
meteorological conditions. This information is made available in a wide
variety of informational documents, dependent upon the manufacturer.
(9) Manufacturer-supplied landing performance data for conditions
worse than a dry smooth runway is normally an analytical computation
based on the dry runway landing performance data, adjusted for a
reduced airplane braking coefficient of friction available for the
specific runway surface condition. Most of the data for runways
contaminated by snow, slush, standing water, or ice were developed to
show compliance with European Aviation Safety Agency and Joint Aviation
Authority airworthiness certification and operating requirements. The
FAA considers the data developed for showing compliance with the
European contaminated runway certification and operating requirements
to be acceptable for making landing distance assessments for
contaminated runways at the time of arrival.
Guidance: Existing Requirements
A review of the current applicable regulations indicates that the
regulations do not specify the type of landing distance assessment that
must be performed at the time of arrival, but operators are required to
restrict or suspend operations when conditions are hazardous. Failure
to ensure an operation can be conducted safely may be considered a
careless or reckless operation. The FAA considers it necessary for
operators to perform such an assessment in order to ensure that the
flight can be safely completed.
Part 121, section 121.195(b), part 135, section 135.385(b), and
part 91, section 91.1037(b) and (c) require operators to comply with
certain landing distance requirements at the time of takeoff. (Part
125, section 125.49 requires operators to use airports that are
adequate for the proposed operation.) These requirements limit the
allowable takeoff weight to that which would allow the airplane to land
within a specified percentage of the landing distance available on: (1)
The most favorable runway at the destination airport under still air
conditions; and (2) the most suitable runway in the expected wind
conditions. Sections 121.195(d), 135.385(d), and 91.1037(e) further
require an additional 15% be added to the required landing distance
when the runway is wet or slippery, unless a shorter distance can be
shown using operational landing techniques on wet runways. Although an
airplane can be legally dispatched under these conditions, compliance
with these requirements alone does not ensure that the airplane can
land safely within the distance available on the runway actually used
for landing in the conditions that exist at the time of arrival,
particularly if the runway, runway surface condition, meteorological
conditions, airplane configuration, airplane weight, or use of airplane
ground deceleration devices is different than that used in the
preflight calculation. Part 121, sections 121.533, 121.535, and
121.537, part 135, section 135.77, part 125, section 125.351, and part
91, sections 91.3 and 91.1009 place the responsibility for the safe
operation of the flight jointly with the operator, pilot in command,
and dispatcher as appropriate to the type of operation being conducted.
Sections 121.195(e) and 135.385(e), allow an airplane to depart
even when it is unable to comply with the conditions referred to in
item (2) of the paragraph above if an alternate airport is specified
where the airplane can comply with conditions referred to in items (1)
and (2) of the paragraph above. This provision implies that a landing
distance assessment is accomplished before landing to determine if it
is safe to land at the destination, or if a diversion to an alternate
airport is required.
Part 121, sections 121.601 and 121.603, require dispatchers to keep
pilots informed, or for pilots to stay informed as applicable, of
conditions, such as airport and meteorological conditions, that may
affect the safety of the flight. The operator and flightcrew use this
information in their safety of flight decision making. Part 121,
sections 121.551, 121.553, and part 135, section 135.69, require an
operator, and/or the pilot in command as applicable, to restrict or
suspend operations to an airport if the conditions, including airport
or runway surface conditions, are hazardous to safe operations. Part
125 section 125.371 prohibits a pilot in command from continuing toward
any airport to which it was released unless the flight can be completed
safely. A landing distance assessment must be made under the conditions
existing at the time of arrival in order to support a determination of
whether conditions exist that may affect the safety of the flight and
whether operations should be restricted or suspended.
Runway surface conditions may be reported using several types of
descriptive terms including: type and depth of contamination, a reading
from a runway friction measuring device, an airplane braking action
report, or an
[[Page 32880]]
airport vehicle braking condition report. Unfortunately, joint industry
and multi-national government tests have not established a reliable
correlation between runway friction under varying conditions, type of
runway contaminants, braking action reports, and airplane braking
capability. Extensive testing has been conducted in an effort to find a
direct correlation between runway friction measurement device readings
and airplane braking friction capability. However, these tests have not
produced conclusive results that indicate a repeatable correlation
exists through the full spectrum of runway contaminant conditions.
Therefore, operators and flightcrews cannot base the calculation of
landing distance solely on runway friction meter readings. Likewise,
because pilot braking action reports are subjective, flightcrews must
use sound judgment in using them to predict the stopping capability of
their airplane. For example, the pilots of two identical aircraft
landing in the same conditions, on the same runway could give different
braking action reports. These differing reports could be the result of
differences between the specific aircraft, aircraft weight, pilot
technique, pilot experience in similar conditions, pilot total
experience, and pilot expectations. Also, runway conditions can degrade
or improve significantly in very short periods of time dependent on
precipitation, temperature, usage, and runway treatment and could be
significantly different than indicated by the last report. Flightcrews
must consider all available information, including runway surface
condition reports, braking action reports, and friction measurements.
Operators and pilots must use the most adverse reliable braking
action report or the most adverse expected conditions for the runway,
or portion of the runway, that will be used for landing when assessing
the required landing distance prior to landing. Operators and pilots
must consider the following factors in assessing the actual landing
distance: the age of the report, meteorological conditions present
since the report was issued, type of airplane or device used to obtain
the report, whether the runway surface was treated since the report,
and the methods used for that treatment. Operators and pilots are
expected to use sound judgment in determining the applicability of this
information to their airplane's landing performance.
The following table provides an example of a correlation between
braking action reports and runway surface conditions:
Relationship Between Braking Action Reports and Runway Surface Condition (Contaminant Type)
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Dry (not
Braking Action reported) Good Fair/Medium Poor Nil
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Contaminant.................. Dry............. Wet, Dry Snow Packed or Wet Snow, Slush Wet ice.
(< 20 mm)..... Compacted Snow. Standing
Water, Ice.
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Relationship between braking action reports and runway surface
condition (contaminant type)
Note: Under extremely cold temperatures, these relationships may
be less reliable and braking capabilities may be better than
represented. This table does not include any information pertaining
to a runway that has been chemically treated or where a runway
friction enhancing substance has been applied.
Some advisory landing distance information uses a standard air
distance of 1000 feet from 50 feet above the runway threshold to the
touchdown point. A 1000 foot air distance is not consistently
achievable in normal operations. Operators are expected to apply
adjustments to this air distance to reflect their specific operations,
operational practices and experience.
To ensure that an acceptable landing distance safety margin exists
at the time of arrival, the FAA, through Operation/Management
Specifications paragraph C082, for turbojet operations, will specify
that at least at fifteen percent safety margin be provided. This safety
margin represents the minimum distance margin that must exist between
the expected actual landing distance at the time of arrival and the
landing distance available, considering the meteorological and runway
surface conditions, airplane configuration and weight, and the intended
use of airplane ground deceleration devices. In other words, the
landing distance available of the runway to be used for landing must
allow a full stop landing, in the actual conditions and airplane
configuration at the time of landing, and at least an additional
fifteen percent safety margin.
New Requirements
The FAA will soon be issuing mandatory OpSpec/MSpec C082, ``Landing
Performance Assessments After Dispatch'' for all turbojet operators.
This OpSpec/MSpec will allow operations based on provisions as set
forth in this notice. If not currently in compliance, all turbojet
operators shall be brought into compliance with this notice and the
requirements of OpSpec/MSpec C082 no later than October 1, 2006. The
FAA anticipates that operators will be required to submit their
proposed procedures for compliance with this notice and OpSpec/MSpec to
their POI no later than September 1, 2006. When the operator
demonstrates the ability to comply with the C082 authorization for
landing distance assessments, and has complied with the training, and
training program requirements below, OpSpec/MSpec C082 should be
issued. OpSpec/MSpec C082 will be available from the FAA by June 30,
2006.
The FAA anticipates that operator compliance with OpSpec/MSpec C082
could be accomplished by a variety of methods and procedurally should
be accomplished by the method that best suits the operator's current
procedures. Under OpSpec/MSpec C082, the operator's procedures would
need to be approved by the Principal Operations Inspector and, if an
operations manual is required for the operator, the procedures would
need to be clearly articulated in the operations manual system for
effected personnel. The following list of methods is not all inclusive,
or an endorsement of any particular methods, but provided as only some
examples of methods of compliance.
Establishment of a minimum runway length required under
the worst case meteorological and runway conditions for operator's
total fleet or fleet type that will provide runway lengths that comply
with this notice and OpSpec/MSpec C082.
The requirements of this paragraph could be considered
along with the other applicable preflight landing distance calculation
requirements and the takeoff weight adjusted to provide for compliance
at time of arrival under the conditions and configurations factored in
the calculation. This information could be provided to the
[[Page 32881]]
flightcrew as part of the release/dispatch documents.
Tab or graphical data accounting for the applicable
variables provided to the flightcrew and/or dispatcher as appropriate
to the operator's procedures.
Electronic Flight Bag equipment that has methods for
accounting for the appropriate variables.
Note: These are only some examples of methods of compliance.
There are many others that would be acceptable as determined through
coordination between the operator and the POI.
Requirements
No later than September 1, 2006, turbojet operators will be
required to have procedures in place to ensure that a full stop
landing, with at least a 15% safety margin beyond the actual landing
distance, can be made on the runway to be used, in the conditions
existing at the time of arrival, and with the deceleration means and
airplane configuration that will be used. This assessment must take
into account the meteorological conditions affecting landing
performance (airport pressure altitude, wind velocity, wind direction,
etc.), surface condition of the runway to be used for landing, the
approach speed, airplane weight and configuration, and planned use of
airplane ground deceleration devices. Turbojet operators will be
required to ensure that flightcrews comply with the operator's approved
procedures. In other words, absent an emergency, after the flightcrew
makes this assessment using the air carrier's FAA-approved procedures,
if at least the 15% safety margin is not available, the pilot may not
land the aircraft.
This assessment does not mean that a specific calculation would be
made before every landing. In many cases, the before takeoff criteria,
with their large safety margins, will be adequate to ensure that there
is sufficient landing distance with at least a 15% safety margin at the
time of arrival. Only when the conditions at the destination airport
deteriorate while en route (e.g., runway surface condition, runway to
be used, winds, airplane landing weight/configuration/speed/
deceleration devices) or the takeoff is conducted under sections
121.195(e) or 135.385(e) would a calculation or other method of
determining the actual landing distance capability normally be needed.
The operator will need to develop procedures to determine when such a
calculation or other method of determining the expected actual landing
distance is necessary to ensure that at least a 15% safety margin will
exist at the time of arrival.
Operators may require flight crews to perform this assessment, or
may establish other procedures to conduct this assessment. Whatever
method(s) the operator develops, their procedures must account for all
factors upon which the preflight planning was based and the actual
conditions existing at time of arrival.
The FAA expects that turbojet operators will likely need to confirm
that the procedures and data used to comply with paragraphs above for
actual landing performance assessments yields results that are at least
as conservative as the manufacturer's approved or advisory information
for the associated conditions provided therein.
Turbojet operators will be required to have a safety margin of
fifteen percent added to the actual (unfactored) landing distance and
the resulting distance must be within the landing distance available of
the runway used for landing. Note that the FAA considers a 15% margin
to be the minimum acceptable safety margin.
If contaminated runway landing distance data are unavailable from
the manufacturer (or STC holder if there is an STC that affects landing
performance), the following factors should be applied to the pre-flight
planning (factored) dry runway landing distances determined in
accordance with the applicable operating rule (e.g., sections 91.1037,
121.195(b) or 135.385(b):
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Factor to apply to (factored) dry
Runway condition Reported braking action runway landing distance*
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Dry................................... None............................... 0.8.
Wet Runway, Dry Snow.................. Good............................... 0.9.
Packed or Compacted Snow.............. Fair/Medium........................ 1.2.
Wet snow, slush, standing water, ice.. Poor............................... 1.6.
Wet ice............................... Nil................................ Landing prohibited.
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* If unfactored dry runway landing distances are used, multiply these factors by 1.667.
Note: These factors assume that maximum manual braking,
autospoilers (if so equipped), and reverse thrust will be used. For
operations without reverse thrust (or without credit for the use of
reverse thrust) multiply these factors by 1.2.
The FAA anticipates that turbojet operators will be required to
accomplish the landing distance assessment as close to the time of
arrival as practicable, taking into account workload considerations
during critical phases of flight, using the most up-to-date information
available at that time. The most adverse braking condition, based on
reliable braking reports, runway contaminant reports (or expected
runway conditions if no reports are available) for the portion of the
runway that will be used for the landing must be used in the actual
landing performance assessment. For example, if the runway condition is
reported as fair to poor, or fair in the middle, but poor at the ends,
the runway condition must be assumed to be poor for the assessment of
the actual landing distance. (This example assumes the entire runway
will be used for the landing). If conditions change between the time
that the assessment is made and the time of landing, the flightcrew
must consider whether it would be safer to continue the landing or
reassess the landing distance.
The operator's flightcrew and dispatcher training programs will
need to include elements that provide knowledge in all aspects and
assumptions used in landing distance performance determinations. This
training must emphasize the airplane ground deceleration devices,
settings, and piloting methods (e.g., air distance) used in determining
landing distances for each make, model, and series of airplane.
Elements such as braking action reports, airplane configuration,
optimal stopping performance techniques, stopping margin, and the
effects of excess speed, delays in activating deceleration devices, and
other pilot performance techniques must be covered. All dispatchers and
flightcrew members must be trained on these elements prior to being
issued OpSpec/MSpec C082.
[[Page 32882]]
Under OpSpec/MSpec C082, it is likely that turbojet operators will
also need to have procedures for obtaining optimal stopping performance
on contaminated runways included in flight training programs. All
flight crewmembers must be made aware of these procedures for the make/
model/series of airplane they operate prior to being issued OpSpec/
MSpec C082. In addition, if not already included, these procedures
shall be incorporated into each airplane or simulator training
curriculum for initial qualification on the make/model/series airplane,
or differences training as appropriate. All flight crewmembers must
have hands-on training and validate proficiency in these procedures
during their next flight training event, unless previously demonstrated
with their current employer in that make/model/series of airplane.
Issued in Washington, DC, on June 1, 2006.
James J. Ballough,
Director, Flight Standards Service.
[FR Doc. 06-5196 Filed 6-6-06; 8:45 am]
BILLING CODE 4910-13-P