Source: https://id.scribd.com/document/227212962/AC120-27D
Timestamp: 2019-09-22 08:40:08
Document Index: 527811558

Matched Legal Cases: ['art 91', 'art 91', 'arts 121', 'art 121', 'art 91', 'arts 121', 'art 125', 'art 125', 'arts 121', 'art 91', 'art 135', 'art 25', 'art 23', 'art 25', 'art 25', 'art 125', 'art 125', 'art 23', 'art 25', 'art 29', 'art 25', 'art 861']

AC120-27D | Kalibrasi | Pesawat Terbang
simpanSimpan AC120-27D Untuk Nanti
MANUAL DE VELO
AC 120-27D DATE: 8/11/04 Initiated By: AFS-200/
Table 1-1. Aircraft Cabin Size ................................................................................................2
CHAPTER 2. AIRCRAFT WEIGHTS AND LOADING SCHEDULES 5 ......................................
201. How does an operator document changes to an aircraft’s we ight and balance?
Incremental Weight Changes that Should Be Recorded in a Weight and
Balance Change Record
202. How does the operator maintain the OEW?.....................................................................6
206. How should an operator determine the weight of each fluid used aboard the aircraft? ..................................................................................................................10
209. What should the operator consider when curtailing the manufacturer’s loading envelope?
210. What are some examples of common curtailments to the manufacturer’s loading envelope?
211. How does an onboard weight and balance system compare to a conventional
weight buildup method?
212. What measures should an operator take to obtain operational approval for
an onboard weight and balance system?
213. What operational considerations should an operator take into account when
using an onboard weight and balance system?
215. What operational considerations should an operator take into account when
using a computerized weight and balance system?
CHAPTER 3. METHODS TO DETERMINE THE WEIGHT OF PASSENGERS
301. What standard average passenger weights should an operator with an approved carry-on bag program use?...........................................................................................21
302. What standard average weights should an operator use for carry-on bags
and personal items?
303. What standard average weights should an operator use for checked bags?..................22
304. What standard average weight should an operator of large cabin aircraft use
for bags checked plane-side?
305. What standard average weights should an operator of small and medium cabin
aircraft use, if it has a “no-carry-on bag program?”
308. What are the standard average weights for special passenger groups that do
not fit an operator’s standard average weight profile?
311. When conducting a survey, can an operator collect a smaller sample size than
that published in Table 3-4?
313. What should an operator consider when developing a survey plan and submitting
it to the FAA?
316. When should an operator conduct another survey to revalidate the data from
an earlier survey?
What should an operator consider when using segmented weights?
317. ............................ Table 3-5. Segmented Weights for Adult Passengers (in Pounds; Summer)
318. How are loading envelope curtailment and bag weight affected by an
operator’s use of segmented weights?
319. What might be an example be of an operator using the segmented weights in
Table 3-5?
320. If the operator decides to use an actual weights program, how might it
determine the actual weight of passengers?
321. If the operator decides to use an actual weight program, how should it
determine the actual weights of personal items and bags?
400. What are the pilots’ and operators’ responsibilities in reporting aircraft
loading and manifest preparation discrepancies?
401. Which FAA inspectors are responsible for overseeing an operator’s weight and
balance program?
402. Which portions of OpSpecs or MSpecs are relevant to an operator’s weight and
APPENDIX 1. DEFINITIONS (4 pages)
APPENDIX 2. SOURCE OF STANDARD AVERAGE WEIGHTS IN THIS AC (1 page)
1. Standard average passenger
2. Standard average bag
Table 2-1. Bag Survey Results................................................................................................1
APPENDIX 3. SAMPLE OPERATIONAL LOADING ENVELOPE (8 pages)
1. Introduction. ........................................................................................................................
2. Assumptions for this
3. Curtailments for passenger seating
Table 3-4. Moments Resulting from the Zone Centroid Assumption for Zone 1 Table 3-5. Moments Resulting from the Window-Aisle-Remaining Assumption
Table 3-7. Moments Resulting from the Zone Centroid Assumption for Zone 2 Table 3-8. Moments Resulting from the Window-Aisle-Remaining Assumption
Table 3-11. Moments Resulting from the Window-Aisle-Remaining Assumption
4. Other curtailments to the manufacturer’s loading
5. Operational loading envelope
Figure 3-2. Operational Loading Envelope with a Curtailment for Variations
in Passenger Seating
Figure 3-3. Operational Loading Envelope Using Actual Seating Location of Passengers ..................................................................................................................8
APPENDIX 4. ADDITIONAL CURTAILMENTS TO CG ENVELOPES TO ACCOUNT FOR VARIATIONS TO PASSENGER WEIGHTS (3 pages)
Table 4-2. Sample Curtailment Due to Variations in Passenger Weight and
Male/Female Ratio Using Window-Aisle Method
APPENDIX 5. OPTIONS TO IMPROVE ACCURACY (7 pages)
APPENDIX 6. SAMPLE CG ENVELOPE DEVELOPMENT (4 pages)
Figure 6-1. Operational CG Envelope3 Passenger Cabin Zones
Figure 6-2. Operational CG EnvelopeActual Passenger Seating
APPENDIX 7. CHECKLIST (3 pages)
a. This AC provides operators with guidance on how to develop and receive approval for a
weight and balance control program for aircraft operated under Title 14 of the Code of Federal
Regulations (14 CFR) part 91, subpart K of part 91, and parts 121, 125, and 135.
b. This AC presents recommendations for an acceptable means, but not the only means, to
develop and receive approval for a weight and balance control program, and includes guidance for using average and estimated weights in accordance with part 121, section 121.153(b) and other applicable parts of subpart K of part 91 and parts 121, 125, and 135.
NOTE: Per part 125, section 125.91(b), no person may operate an airplane in a part 125 operation unless the current empty weight and center of gravity (CG) are calculated from the values established by actual weighing of the airplane within the preceding 36 calendar-months.
c. If an operator adopts the suggestions contained in this AC, the operator must ensure that, when appropriate, it replaces discretionary language such as “should” and “may” with mandatory
language in relevant manuals, operations specifications (OpSpecs), or management specifications (MSpecs).
This AC has four main chapters and seven appendixes. Chapter 1 contains general information about this AC and background. Chapter 2 addresses aircraft weighing and loading schedules. Chapter 3 describes different methods to determine the weight of passengers and bags. Chapter 4 addresses the Federal Aviation Administration’s (FAA) role in developing and approving an operator’s weight and balance control program. Finally, appendixes 1 through 7 contain technical information such as definitions, the source of data used in the AC, a sample loading envelope, an example of curtailments to the loading envelope, suggestions to improve accuracy, sample CG envelope development, and checklists for operators.
b. Joint Handbook Bulletin for Airworthiness (HBAW) 95-14 and Air Transportation
(HBAT) 95-15, Adherence to Advisory Circular 120-27C, “Aircraft Weight and Balance Control,” dated November 17, 1995.
a. Accurately calculating an aircraft’s weight and CG before flight is essential to comply
with the certification limits established for the aircraft. These limits include both weight and CG limits. By complying with these limits and operating under the procedures established by the manufacturer, an operator is able to meet the weight and balance requirements specified in the aircraft flight manual (AFM). Typically, an operator calculates takeoff weight by adding the operational empty weight (OEW) of the aircraft, the weight of the passenger and cargo payload, and the weight of fuel. The objective is to calculate the takeoff weight and CG of an aircraft as accurately as possible.
b. When using average weights for passengers and bags, the operator must be vigilant to
ensure that the weight and balance control program reflects the reality of aircraft loading. The FAA will periodically review the guidance in this AC and update this AC if average weights of the traveling public should change or if regulatory requirements for carry-on bags or personal items should change. Ultimately, the operator is responsible for determining if the procedures described in this AC are appropriate for use in its type of operation.
a. This document provides guidance to operators that are either required to have an approved
weight and balance control program under parts 121 and 125, or choose to use average aircraft, passenger or baggage weights when operating under subpart K of part 91 or part 135. The
guidance in this AC is useful for anyone involved in developing or implementing a weight and balance control program.
b. As shown in Table 1-1, the FAA has divided aircraft into three categories for this AC to
provide guidance appropriate to the size of the aircraft.
A large-cabin aircraft. A medium-cabin aircraft.
0 to 4 passenger seats
a. Standard Average Weights. Use of standard average weights is limited to operators of
multiengine turbine-powered aircraft originally type-certificated for five (5) or more passenger seats who hold a letter of authorization (LOA), OpSpecs, or MSpecs, as applicable, and were certificated under 14 CFR part 25, 29, or part 23 commuter category or the operator and manufacturer is able to prove that the aircraft can meet the performance requirements of subpart B of part 25. Single-engine and multiengine turbine Emergency Medical Service
Helicopter (EMS/H) operators may use standard average weights for EMS operations, provided they have received an LOA.
b. Segmented Weights. Use of segmented weights is limited to those aircraft that meet the
requirements of paragraph 105(a) or that are multiengine turbine-powered aircraft originally type-certificated for five (5) or more passenger seats and that do not meet the performance requirements of subpart B of part 25. Segmented passenger weights are listed in Chapter 3, Table 3-5.
Prior to being placed into service, each aircraft should be weighed and the empty weight and CG location established. New aircraft are normally weighed at the factory and are eligible to be placed into operation without reweighing if the weight and balance records were adjusted for alterations and modifications to the aircraft and if the cumulative change to the weight and balance log is not more than plus or minus one-half of one percent (0.5 percent) of the maximum landing weight or the cumulative change in the CG position exceeds one-half of one percent (0.5 percent) of the mean aerodynamic chord. Aircraft transferred from one operator that has an approved weight and balance program, to another operator with an approved program, need not be weighed prior to use by the receiving operator unless more than 36 calendar-months have elapsed since last individual or fleet weighing, or unless some other modification to the aircraft warrants that the aircraft be weighed (e.g., paragraph 203(c)). Aircraft transferred, purchased, or leased from an operator without an approved weight and balance program, and that have been unmodified or only minimally modified, can be placed into service without being reweighed if the last weighing was accomplished by a method established through an operator’s approved weight and balance control program within the last 12 calendar-months and a weight and balance change record was maintained by the operator. See paragraph 203(c) for a discussion of when it may be potentially unsafe to fail to reweigh an aircraft after it has been modified.
201. How does an operator document changes to an aircraft’s weight and balance?
INCREMENTAL WEIGHT CHANGES THAT SHOULD BE RECORDED IN A WEIGHT AND BALANCE CHANGE RECORD
+/-10 lb or greater.
Large-cabin aircraft Medium-cabin aircraft
Small-cabin aircraft
5 lb or greater. 1 lb or greater.
a. Establishment of OEW. The OEW and CG position of each aircraft should be
reestablished at the reweighing periods discussed in paragraph 203. In addition, it should be reestablished whenever the cumulative change to the Weight and Balance Log is more than plus or minus one-half of 1 percent (0.5 percent) of the maximum landing weight, or whenever the cumulative change in the CG position exceeds one-half of 1 percent (0.5 percent) of the mean aerodynamic chord (MAC). In the case of helicopters and airplanes that do not have a MAC- based CG envelope (e.g., canard equipped airplane), whenever the cumulative change in the CG position exceeds one-half of 1 percent (0.5 percent) of the total CG range, the weight and balance should be reestablished.
b. Fleet Operating Empty Weights (FOEW). An operator may choose to use one weight
for a fleet or group of aircraft if the weight and CG of each aircraft is within the limits stated
above for establishment of OEW. When the cumulative changes to an aircraft Weight and Balance Log exceed the weight or CG limits for the established fleet weight, the empty weight for that aircraft should be reestablished. This may be done by moving the aircraft to another group, or reestablishing new FOEWs.
a. Individual Aircraft Weighing Program. Aircraft are normally weighed at intervals of
36 calendar-months. An operator may, however, extend this weighing period for a particular model aircraft when pertinent records of actual routine weighing during the preceding period of operation show that weight and balance records maintained are sufficiently accurate to indicate that aircraft weights and CG positions are within the cumulative limits specified for establishment of OEW, (see paragraph 202). Such applications should be substantiated in each instance with at least two aircraft weighed. Under an individual aircraft weighing program, an increase should not be granted which would permit any aircraft to exceed 48 calendar-months since the last weighing, including when an aircraft is transferred from one operator to another. In the case of helicopters, increases should not exceed a time that is equivalent to the aircraft overhaul period.
NOTE: Per part 125, section 125.91(b), no person may operate an airplane in a part 125 operation, unless the current empty weight and center of gravity (CG) are calculated from the values established by actual weighing of the airplane within the preceding 36 calendar-months.
b. Fleet Weighing. An operator may choose to weigh only a portion of the fleet and apply
the unaccounted weight and moment change determined by this sample to the remainder of the
(1) A fleet is composed of a number of aircraft of the same model (For example, B747-200s in a passenger configuration and B747-200 freighters should be considered different
fleets. Likewise, B757-200s and B757-300s should be considered different fleets). The primary purpose of defining a fleet is to determine how many aircraft should be weighed in each weighing cycle. A fleet may be further divided into groups to establish FOEWs.
1 to 3 aircraft
4 to 9 aircraft
3 aircraft, plus at least 50 percent of the number of aircraft greater than 3.
More than 9 aircraft
6 aircraft, plus at least 10 percent of the number of aircraft greater than 9.
c. Weighing AircraftModifications. For most aircraft modifications, computing the
weight and balance changes is practical. For some modifications, such as interior reconfigurations, the large number of parts removed, replaced, and installed make an accurate determination of the weight and balance change by computation impractical. It would be potentially unsafe to fail to reestablish the aircraft weight and balance, by actually reweighing the aircraft, in situations where the cumulative net change in the weight and balance log exceeds:
(1) In the case of airplanes, plus or minus one-half of 1 percent (0.5 percent) of the maximum landing weight, or whenever the cumulative change in the CG position exceeds one- half of 1 percent (0.5 percent) of the MAC.
NOTE: In the situations specified in paragraphs 203c(1) and (2), the operator should weigh two or more aircraft in a fleet, as required in Table 2-2, to get consistent results. The operator may choose to weigh the aircraft before and after the modification, or just after the modification.
a. An operator should take precautions to ensure that it weighs an aircraft as accurately as
possible. These precautions include checking to ensure that all required items are aboard the aircraft and the quantity of all fluids aboard the aircraft is considered. An operator should weigh aircraft in an enclosed building because scale readings stabilize faster in the absence of drafts from open doors.
b. An operator should establish and follow instructions for weighing the aircraft that are
consistent with the recommendations of the aircraft manufacturer and scale manufacturer. The operator should ensure that all scales are certified and calibrated by the manufacturer or a certified laboratory, such as a civil department of weights and measures, or the operator may calibrate the scale under an approved calibration program. The operator should also ensure that the scale is calibrated within the manufacturer’s recommended time period, or time periods, as
specified in the operator’s approved calibration program.
a. The loading schedule is used to document compliance with the certificated weight and balance limitations contained in the manufacturer’s AFM and weight and balance manual.
b. The loading schedule is developed by the operator based on its specific loading
calculation procedures and provides the operational limits for use with the operator’s weight and balance program approved under this AC. These approved operational limits are typically more restrictive but do not exceed the manufacturer’s certificated limits. This is because the loading schedule is generally designed to check only specific conditions (e.g., takeoff and zero fuel) known prior to takeoff, and must account for variations in weight and balance in flight. It must also account for factors selected to be excluded, for ease of use, from the calculation process. Loading the aircraft so that the calculated weight and balance is within the approved limits will maintain the actual weight and balance within the certificated limits throughout the flight.
c. Development of a loading schedule represents a trade-off between ease of use and loading
flexibility. A schedule can provide more loading flexibility by requiring more detailed inputs, or it can be made easier to use by further limiting the operational limits to account for the uncertainty caused by the less detailed inputs.
d. Several types of loading schedules are commonly-used, including computer programs as
well as “paper” schedules, which can be either graphical, such as an alignment (“chase around chart”) system, slide rule, or numerical, such as an adjusted weight or index system.
e. It is often more convenient to compute the balance effects of combined loads and to
display the results by using “balance units” or “index units.” This is done by adding the respective moments (weight times arm) of each item. Graphing the moments results in a “fan grid” where lines of constant balance arms (BA) or % MAC are closer together at lower weights and further apart at higher weights. Direct graphical or numerical addition of the balance effects are possible using these moment values.
f. To make the magnitude of the numbers more manageable, moments can be converted to
an index unit. For example:
NOTE: Where datum is the reference BA that will plot as a vertical line on the fan grid, M and K are constants that are selected by the operator. M is used to scale the index values, and K is used to set the index value of the reference BA.
f. Maximum floor loadingsincluding both running and per square foot limitations.
209. What should the operator consider when curtailing the manufacturer’s loading
a. The operator should curtail the manufacturer’s loading limitations to account for loading
variations and in-flight movement that are encountered in normal operations. For example, if passengers are expected to move about the cabin in flight, the operator must curtail the manufacturer’s CG envelope by an amount necessary to ensure that movement of passengers does not take the aircraft outside its certified envelope. If the aircraft is loaded within the new, curtailed envelope, it will always be operated within the manufacturer’s envelope, even though some of the loading parameters, such as passenger seating location, are not precisely known.
b. In some cases an aircraft may have more than one loading envelope for preflight planning
and loading. Each envelope must have the appropriate curtailments applied for those variables that are expected to be relevant for that envelope. For example, an aircraft might have separate
takeoff, in-flight, and landing envelopes. Passengers are expected to remain seated in the cabin during take-off or landing. Therefore, the takeoff and landing envelope need not be curtailed for passenger movement.
c. Upon determination of the curtailed version of each envelope, the most restrictive points
(for each condition the operator’s program will check) generated by an “overlay” of the envelopes will form the aircraft operational envelopes. These envelopes must be observed. By restricting operation to these “operational envelopes,” compliance with the manufacturer’s certified envelope will be ensured in all phases of flight, based upon the assumptions within the curtailment process. Optionally, an operator may choose to not combine the envelopes but observe each envelope independently. However, due to calculation complexity, this is typically only possible through automation of the weight and balance calculation.
210. What are some examples of common curtailments to the manufacturer’s loading
The following subparagraphs provide examples of common loading curtailments. They are only examples. Operators using an approved weight and balance control program must include curtailments appropriate to the operations being conducted. Each of the items mentioned below is a single curtailment factor. The total curtailment of the manufacturer’s envelope is computed by combining the curtailments resulting from each of these factors.
a. Passengers. The operator must account for the seating of passengers in the cabin. The
loading envelope need not be curtailed if the actual seating location of each passenger is known.
If assigned seating is used to determine passenger location, the operator must implement procedures to ensure that the assignment of passenger seating is incorporated into the loading procedure. It is recommended that the operator take into account the possibility that some passengers may not sit in their assigned seats.
b. Fuel. The operator’s curtailed loading envelope must account for the effects of fuel. The
following are examples of several types of fuel-related curtailments:
c. Fluids. The operator’s curtailed CG envelope must account for the effects of galley and lavatory fluids. These factors include such things as:
d. In-Flight Movement of Passenger and Crew. The operational envelope must account
for the in-flight movement of passengers, crew, and equipment. This may be done by including a curtailment equal to the moment change caused by the motion being considered. It may be assumed that all passengers, crew, and equipment are secured when the aircraft is in the takeoff or landing configuration. Standard operational procedures may be taken into account. Examples of items that can move during flight are:
(3) Service carts moving throughout the cabin. Operators should take their standard operating procedures into account. If procedures do not dictate otherwise, it should be assumed that the service carts can travel anywhere within the compartment to which they are assigned. If multiple carts are in a given compartment, and no restrictions are placed on their movement, then the maximum number of carts, moving the maximum distance, must be considered. The weight of the number of flight attendants assigned to each cart must also be considered. The assumed weight of each cart may be the maximum anticipated cart-load or the maximum design load, as appropriate to the operator’s procedures.
(5) Passengers moving to the lavatory.
Operators should account for the CG change
caused by passengers moving to the lavatory. Operators should develop reasonable scenarios for the movement of passengers in their cabins and consider the CG shifts that can be expected to occur. Generally, it may be assumed that passengers to move to the lavatories closest to their seats. In aircraft with a single lavatory, movement from the “most adverse” seat must be taken into account. Assumptions may be made which reflect operator lavatory and seating policies. For example, it may be assumed that coach passengers may only use the lavatories in the coach cabin, if that is the operator’s normal policy.
211. How does an onboard weight and balance system compare to a conventional weight
buildup method?
a. An operator may use an onboard weight and balance system to calculate an aircraft’s
weight and balance, provided the FAA has approved the system for use in an operator’s weight and balance control program. This section discusses the differences an operator should consider when using an onboard weight and balance system compared to a conventional weight buildup method. This section addresses only the operational considerations related to the use of an FAA- authorized onboard weight and balance system.
b. Like operators using a conventional weight buildup method to calculate weight and
balance, an operator using an onboard weight and balance system as a primary weight and balance control system should curtail the manufacturer’s loading envelope to ensure the aircraft does not exceed the manufacturer’s certificated weight and CG limits. However, an operator using an onboard weight and balance system would not need to curtail the loading envelope for assumptions about passenger and bag weight or distribution.
c. Because an onboard weight and balance system measures the actual weight and CG
location of an aircraft, an operator may not need to include certain curtailments to the loading envelope to account for variables such as passenger seating variation or variation in passenger weight. However, an operator should curtail the loading envelope for any system tolerances that may result in CG or weight errors. Using an onboard weight and balance system does not relieve an operator from the requirement to complete and maintain a load manifest.
212. What measures should an operator take to obtain operational approval for an
onboard weight and balance system?
a. System calibration. An operator should develop procedures to calibrate its onboard
weight and balance system equipment periodically in accordance with the manufacturer’s instructions. An operator may calibrate its system with operational items or fuel aboard the aircraft to test the system at a representative operational weight. However, an operator may not use an onboard weight and balance system in place of procedures described in Section 1 of this chapter for weighing the aircraft to establish OEW or CG location.
b. Demonstration of system accuracy. As part of the operational approval process, an
operator should demonstrate that its onboard weight and balance system maintains its certificated system accuracy between calibration periods. An operator should not have to conduct this demonstration more than once for installing a specific system on one type of aircraft. For the
demonstration, the operator should use an aircraft in normal operational service, or in operations that represent the expected environmental and operational conditions in which the aircraft will operate.
213. What operational considerations should an operator take into account when using an
a. Certification limits. An operator using an onboard weight and balance system as its
primary means of calculating weight and balance should have procedures in place to ensure that
the system is operated within the limits established during the system’s certification process.
b. Environmental considerations. An operator using an onboard weight and balance
system should ensure that it uses the system within the environmental limits established by the
manufacturer. Environmental conditions that may affect the performance of an onboard weight and balance system include temperature, barometric pressure, wind, ramp slope, rain, snow, ice, frost, dew, deicing fluid, etc.
c. Aircraft considerations. An operator using an onboard weight and balance system
should ensure the weight and CG measured by the system are not affected by the aircraft configuration, such as the movement of flaps, stabilizers, doors, stairways or jetways, or any connections to ground service equipment. Other factors that an operator should consider include engine thrust, oleo strut extension, and aircraft taxi movement.
d. Takeoff trim settings. If the aircraft manufacturer provides trim settings for takeoff
based on the aircraft’s CG location, an operator using an onboard weight and balance system
should ensure that the onboard weight and balance system provides flight crewmembers with adequate information to determine the appropriate trim setting.
e. Operational envelope. The operational envelope for onboard weight and balance
systems shall be developed using the same procedures described in other parts of this AC, with the exception that the operational envelope need not be curtailed for passenger random seating and passenger weight variance. Also note that the fuel load is subtracted from the measured takeoff weight to determine the zero fuel weight and CG, instead of being added to the zero fuel weight as part of the load buildup. In addition, an operator must curtail the CG envelope for any system CG tolerance and the weight must be curtailed for any system tolerance above 1 percent.
f. Complying with compartment or unit load device (ULD) load limits. When using an
onboard weight and balance system, an operator should develop in its weight and balance control program a method to ensure that it does not exceed the load limits specified for a compartment or
ULD. If an operator develops appropriate procedures, an operator may request approval to exclude bag counts from its load manifest. The following are two examples of acceptable means to demonstrate compliance with compartment load limits.
(2) By conducting sample loadings, an operator may demonstrate that the average density of the bags it places in a compartment or ULD would not allow it to exceed the compartment or ULD load limits inadvertently.
An operator using an onboard weight and balance system as its primary means of calculating weight and balance may use the guidance in this AC to develop a backup system based on a conventional weight buildup. If an operator develops and receives approval for a backup system, the FAA may grant the operator relief to include an onboard weight and balance system in the operator’s minimum equipment list.
215. What operational considerations should an operator take into account when using a
computerized weight and balance system?
a. An operator may use an installed computerized weight and balance system to calculate the
load schedule for the aircraft’s weight and balance for primary dispatch, provided that the system
received certification and operational approval for use in an operator’s approved weight and balance control program. The system consists of a computer program that runs on installed Electronic Flight Bag computing devices or the Aircraft Communication Addressing and Reporting System, and can be downloaded to ground operations via electronic links. The system displays the load sheet to the pilot or flight operations for primary dispatch.
balance, an operator may use the computerized weight and balance system to provide the FAA approved loading schedules. The operator who uses the computerized weight and balance system as part of its approved weight and balance program should meet all provisions pertinent
to the operator’s approved weight and balance program as described in this AC.
a. For many years, operators of transport category aircraft have used average weights for
passengers and bags to calculate an aircraft’s weight and balance, in accordance with standards and recommended practices. This method eliminates many potential sources of error associated with accounting for a large number of relatively light weights. However, differences between the actual weight of passengers and bags and the average weight of passengers and bags can occur when using average weights.
b. Statistical probability dictates that the smaller the sample size (i.e., cabin size), the more
the average of the sample will deviate from the average of the larger universe. Because of this, the use of standard average passenger weights in weight and balance programs for small and medium cabin aircraft should be examined in greater detail.
c. The next four sections describe four methods available to operators to determine
passenger and bag weight. They are standard average weights in Section 2; average weights based on survey results in Section 3; segmented weights in Section 4; and actual weights in
Section 5. An operator should review the following discussion and consult Table 3-1 to determine which method or methods are appropriate to its type of operation.
d. Large Cabin Aircraft. Operators of large cabin aircraft may use the standard average
weights for passengers and bags. If an operator determines that the standard average weights are not representative of its operation for some route or regions, it is encouraged to conduct a survey as detailed in Section 3 of this chapter, to establish more appropriate average weights for its operation. Operators should have procedures for identifying situations that would require the use of nonstandard or actual weights.
e. Medium Cabin Aircraft. Medium cabin aircraft should be evaluated to determine if the
aircraft should be treated more like large or small cabin aircraft. To determine if a medium cabin aircraft can be treated as a large cabin aircraft, the aircraft must meet either both of the
loadability criteria or the loading schedule criteria or else be subject to the small cabin weights and curtailments:
The CG of the OEW is within the manufacturer’s loading envelope, and
The CG of the zero fuel weight is within the manufacturer’s loading envelope when loaded with a full load of passengers and all cargo compartments are filled with a density of 10 pounds per cubic foot.
The operator must use a loading schedule based upon zones. The aircraft cabin may have no more than four rows per zone with not less then four zones.
f. Small Cabin Aircraft. Operators of small cabin aircraft may request approval to use any
one of the following methods when calculating the aircraft weight and balance.
(3) The operator may use the standard average passenger and bag weights prescribed for large cabin aircraft, or average weights based on an FAA-accepted survey, if
(a) The aircraft was certificated under part 23 commuter category, part 25, or part 29
(or is able to prove an aircraft has equivalent part 25 or 29 performance data), and
(b) The operator curtails the aircraft CG envelope as prescribed in Appendixes 3
and 4 of this AC.
b. The standard average passenger weights in Table 3-1 include 5 pounds for summer
clothing, 10 pounds for winter clothing, and a 16-pound allowance for personal items and carry-on bags. Where no gender is given, the standard average passenger weights are based on the assumption that 50 percent of passengers are male and 50 percent of passengers are female.
Standard Average Passenger Weight Summer Weights
Average adult female passenger weight Child weight (2 years to less than 13 years of age)
c. An operator may use summer weights from May 1 to October 31 and winter weights from
November 1 to April 30. However, these dates may not be appropriate for all routes or operators. For routes with no seasonal variation, an operator may use the average weights appropriate to the climate. Use of year-round average weights for operators with seasonal variation should avoid using an average weight that falls between the summer and winter average weights. Operators with seasonal variation that elect to use a year-round average weight should use the winter average weight. Use of seasonal dates, other than those listed above, will be entered as nonstandard text and approved through the operator’s OpSpec, MSpec, or LOA, as applicable.
d. The standard average weights listed in Table 3-1 are based on the assumption that the
operator has a carry-on bag program. Operators using a no-carry-on bag program should refer to paragraph 305 of this section.
302. What standard average weights should an operator use for carry-on bags and
a. An operator using standard average passenger weights should include the weight of
carry-on bags and personal items in the passenger’s weight. The standard average passenger weights in Table 3-1 include a 16-pound allowance for personal items and carry-on bags, based on the assumption that—
b. If an operator believes the 16-pound allowance for personal items and carry-on bags is not
appropriate for its operations or receives notification from the FAA that the assumptions provided in paragraph 302a are not consistent with the operator’s approved program, the operator should conduct a survey to determine what percentage of passengers carry personal items or carry-on bags aboard the aircraft. An example of how to adjust the personal item and carry-on bag allowance, based on the results of a survey, is in Section 3. An operator should not use an allowance of less than 16 pounds for personal items and carry-on bags unless the operator conducts a survey or unless the operator has a no-carry-on bag program.
a. Heavy bags. Heavy bags are considered any bag that weighs more than 50 pounds
but less than 100 pounds. An operator should account for a heavy bag by using one of the following weights:
NOTE: An operator that uses “double-counting” to treat a heavy bag as if it were two checked bags for weight purposes should ensure the load manifest represents the actual number of bags for counting purposes. An operator
should have a system in place to ensure that heavy bags are identified, although operators may not be required to weigh heavy bags on a scale.
b. Non-luggage bags. A non-luggage bag is any bag that does not meet the normal criteria
for luggage. Examples include golf bags, fishing equipment packages, wheelchairs and strollers in their shipping configuration, windsurfing kits, boxed bicycles, etc. For non-luggage bags, operators may use any appropriate combination of actual weights, average weights based on survey results, or standard average bag weights. Operators that wish to establish an average weight for a particular type of non-luggage bag, such as a golf bag, must conduct a survey in accordance with the procedures established in Section 3 of this chapter. Operators also should establish a method to calculate the effect on CG of a large non-luggage bag, such as a surfboard, that may occupy more than one compartment on the aircraft.
304. What standard average weight should an operator of large cabin aircraft use for bags
checked plane-side?
NOTE: A no-carry-on bag program is limited to small and medium cabin aircraft. A no-carry-on bag program is a term of art created for this AC. Associated with this program are certain standard average weight credits and reductions. Nothing in this AC prevents an operator of large cabin aircraft from having a no-carry-on bag “policy;” however, the acceptable standard bag weights for such checked baggage for large cabin aircraft are outlined in paragraphs 303 and 304 above. Furthermore, the passenger weight credit associated with a no-carry-on-bag program is limited to the small and medium cabin aircraft.
a. An operator with a no-carry-on bag program may allow passengers to carry only personal
items aboard the aircraft. Because these passengers do not have carry-on bags, an operator may use standard average passenger weights that are 6 pounds lighter than those for an operator with an approved carry-on bag program. See Table 3-2.
Average Passenger Weight Summer Weights
Average passenger weight
Average male passenger weight Average female passenger weight
Average male passenger weight
Average female passenger weight Child weight (2 years to less than 13 years of age)
b. An operator that has a no-carry-on bag program may account for a plane-side loaded bag
as 20 pounds. To receive authorization to use 20 pounds as the average weight for a plane-side
loaded bag, an operator should demonstrate that sufficient controls exist to ensure that passengers do not bring carry-on bags aboard the aircraft. An operator also should demonstrate that sufficient controls exist to ensure the personal items brought aboard the aircraft can fit completely under a passenger seat or in an approved stowage compartment.
c. If an operator discovers that a plane-side loaded bag should have been treated as a
checked bag, the operator should account for that bag at the standard average weight of
30 pounds for a checked bag.
Flight crewmember Flight attendant
Female flight attendant Crewmember roller bag
Pilot flight bag Flight attendant kit
b. The flight crewmember weights in Table 3-3 were derived from weights listed on all
first- and second-class medical certificates. The flight crewmember weight with bags assumes that each flight crewmember has one crewmember roller bag and one pilot flight bag.
c. The flight attendant weights in Table 3-3 were derived from National Health and Nutrition
Examination Survey (NHANES) data. (For additional information on NHANES, see Appendix 2.) The flight attendant weights with bags assume that each flight attendant has one
crewmember roller bag and one flight attendant kit.
d. An operator may include the weight of crewmembers in an aircraft’s OEW or add the
weight to the load manifest prepared for each flight.
b. Mail. An operator should use the weights provided with manifested mail shipments to
account for the weight of the mail. If an operator has to separate a shipment of mail, the operator
may make actual estimates about the weight of the individual pieces, provided the sum of the estimated weights is equal to the actual manifested weight of the entire shipment.
308. What are the standard average weights for special passenger groups that do not fit an
operator’s standard average weight profile?
(3) A standard allowance of 16 pounds per person may be used to account for carry-on and personal items as provided in the operator’s approved carry-on bag program.
(4) If the carry-on bags are representative of the operator’s profile but do not meet the number of bags authorized per person, the operator may count bags and use a 16 pounds per bag allocation.
(5) Actual weights must be used in cases where the carry-on bags are not representative of the operator’s profile.
c. Military Groups. The Department of Defense (DOD) requires actual passenger and
cargo weights be used in computing the aircraft weight and balance for all DOD charter missions. This requirement is specified in DOD Commercial Air Carrier Quality and Safety requirements (reference 32 CFR part 861, section 861.4(e)(3)(ix), as revised). FAA-approved air
carrier weight and balance control programs may be used to account for carry-on/personal items for mixed loads of military and their dependents (such as channel missions). For combat- equipped troop charters, the Air Mobility Command (AMC) will provide guidance to account for the additional weight. If aircraft operators perceive that the weights provided are understated, they should seek confirmation of the actual weights and should make reasonable upward estimations and adjustments to those passenger and/or bag weights.
a. This section provides operators with an acceptable survey method to use in determining
average weights for a weight and balance control program. This section also describes how an operator can conduct a survey to count personal items and carry-on bags to determine an appropriate allowance for those items to include in passenger weight. In addition, an operator may use the methods described in this section to conduct a survey to determine the percentage of male and female passengers, to calculate an average passenger weight.
b. Surveys conducted correctly allow an operator to draw reliable inferences about large
populations based on relatively small sample sizes. In designing a survey, an operator should
Adult (standard adult/male/female)
Plane-side loaded bags Personal items and carry-on bags
Personal items only (for operators with no carry-on bag program)
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311. When conducting a survey, can an operator collect a smaller sample size than that
published in Table 3-4?
s is the standard deviation is the number of points surveyed
is the individual survey weights
is the tolerable error
a. An operator conducting a survey must employ random sampling techniques. Random
sampling means that every member of a group has an equal chance of being selected for inclusion in the sample. If an operator conducts a survey that does not employ random sampling, the characteristics of the selected sample may not be indicative of the larger group as a whole. Because of this, any conclusions drawn from such a survey may not be valid.
b. The following are two examples of random sampling methods that an operator may find
appropriate for the type of survey conducted. An operator may also consult a basic textbook on
statistics to determine if another random sampling method is more appropriate.
(1) Simple random selection. An operator should assign a sequential number to each item in a group (such as passengers waiting on a lin e or bag claim tickets). Then the operator randomly selects numbers and includes the item corresponding with the number in the sample. The operator repeats this process until it has obtained the minimum sample size.
(2) Systematic random selection. An operator should randomly select an item in sequence to begin the process of obtaining samples. The operator should then use a
predetermined, systematic process to select the remaining samples following the first sample. For example, an operator selects the third person in line to participate in the survey. The operator then selects every fifth person after that to participate in the survey. The operator continues selecting items to include in the sample until it has obtained the minimum sample size.
c. Regardless of the sampling method used, an operator has the option of surveying each
passenger and bag aboard the aircraft and should always give a passenger the right to decline to
participate in any passenger or bag weight survey. If a passenger declines to participate, the operator should select the next passenger based on the operator’s random selection method rather than select the next passenger in a line. If a passenger declines to participate, an operator should not attempt to estimate data for inclusion in the survey.
313. What should an operator consider when developing a survey plan and submitting it to
b. Submitting the survey plan to the FAA. It is recommended that an operator submit its
survey plan to the FAA at least 2 weeks before the survey is expected to begin. Before the
survey begins, the operator’s principal inspectors (PI) will review the plan and work with the operator to develop a mutually acceptable plan. During the survey, the PI will oversee the survey process to validate the execution of the survey plan. After the survey is complete, the PI will review the survey results and issue the appropriate OpSpecs or MSpecs. Once a survey begins, the operator should continue the survey until complete, even if the initial survey data indicates that the average weights are lighter or heavier than expected.
a. Survey locations. An operator should accomplish a survey at one or more airports that
represent at least 15 percent of an operator’s daily departures. To provide connecting passengers with an equal chance of being selected in the survey, an operator should conduct its survey within the secure area of the airport. An operator should select locations to conduct its survey that would provide a sample that is random and representative of its operations. For example, an operator should not conduct a survey at a gate used by shuttle operations unless the operator is conducting a survey specific to that route or the operator only conducts shuttle operations.
b. Weighing passengers. An operator that chooses to weigh passengers as part of a survey
should take care to protect the privacy of passengers. The scale readout should remain hidden from public view. An operator should ensure that any passenger weight data collected remains confidential.
d. Rounding sample results. If the operator uses rounding in the weight and balance
calculations, it is recommended that the operator round passenger weights to the nearest pound and bag weights to the nearest half-pound. An operator should ensure that rounding is done consistently in all calculations.
a. An operator may conduct a survey to count certain items without determining the weight
of those items. For example, an operator may determine that the standard average weights for male and female passengers are appropriate for its operations, but on some routes the passengers are predominantly male or female. In this case, an operator may conduct a survey to determine the percentage of male and female passengers. The operator could use the results of the survey to justify a weight other than the standard weights, which assume a 50-percent male and 50-percent female mix of passengers. Similarly, an operator may conduct a survey to determine the number of personal items and carry-on bags passengers carry aboard aircraft to determine if the allowance of 16 pounds per passenger is appropriate to its operations.
b. For example, an operator conducts a survey on a particular route (or multiple routes if
amending the program average weight) to count the percentage of passengers carrying personal items and carry-on bags. The operator finds that—
NOTE: The calculation below determines the appropriate allowance for personal items and carry-on bags.
[0.50 × (16 pounds + 16 pounds)] + [0.30 × (16 pounds)] + [0.20 ×(0 pounds)] = 20.8 pounds
The concept of segmented weights involves adding a portion of the standard deviation to an average weight to increase the confidence that the actual weight will not exceed the average weight. Like the standard average weights in Section 2, the segmented weights in Table 3-5 were derived from average weights and standard deviations found based on NHANES data, assuming a 95-percent confidence interval and 1-percent tolerable error.
Use actual weights, or asked (volunteered) weights plus 10 lb
An operator may make the following adjustments to the table above:
An operator may interpolate between columns on the chart if the operator’s assumed ratio of male passengers to female passengers does not exactly match the values given.
To account for a child’s weight, for children ages 2 years to less than 13 years of age, the
standard average child weight located in Table 3-1 may be used. Weights of children under the
age of 2 have been factored into the segmented adult passenger weight.
How are loading envelope curtailment and bag weight affected by an operator’s use of
segmented weights?
Loading envelope curtailment. An operator using segmented passenger weights should consider curtailing its operational loading envelope using the methods described in Appendix 4.
b. Bag weights. An operator using segmented weights may use actual weights for bags or
the standard average bag weights provided in Section 2. An operator using segmented passenger weights may not use survey-derived average bag weights.
319. What might be an example be of an operator using the segmented weights in Table 3-5?
An operator of a 30 passenger-seat aircraft conducts a survey to count the percentage of male and female passengers on its flights and determines that 50 percent of its passengers are male and 50 percent are female. If the operator has an approved carry-on bag program, the operator should use 204 pounds in the summer and 209 pounds in the winter. If the operator has a no- carry-on bag program, the operator should use 198 pounds in the summer and 203 pounds in the winter and account for all plane-side loaded bags as 20 pounds each.
320. If the operator decides to use an actual weights program, how might it determine the
actual weight of passengers?
a. Weighing each passenger on a scale before boarding the aircraft (types of weight scales
and scale tolerances will be defined in the operator’s approved weight and balance control
program); or
b. Asking each passenger his or her weight. An operator should add to this asked
(volunteered) weight at least 10 pounds to account for clothing. An operator may increase this
allowance for clothing on certain routes or during certain seasons, if appropriate.
321. If the operator decides to use an actual weight program, how should it determine the
actual weights of personal items and bags?
400. What are the pilots’ and operators’ responsibilities in reporting aircraft loading and manifest preparation discrepancies?
The FAA has divided the responsibility of overseeing an operator’s weight and balance control program between the operator’s principal operations inspector (POI) and principal maintenance inspector (PMI). An operator that wishes to change aspects of its weight and balance control program, including average weights, should submit all applicable supporting data to the POI and PMI, as applicable, for approval. If the FAA approves the changes, the FAA will issue revised OpSpecs, MSpecs, or LOA, as appropriate.
b. Parts A and E of OpSpecs or MSpecs authorize an operator’s weight and balance control
program. These parts will address—
c. Paragraph E096 of the OpSpecs or MSpecs is issued to an operator with an approved aircraft fleet actual or average weight program. The FAA issues this paragraph after reviewing and approving an operator’s weight and balance control program in its entirety.
d. Paragraph A011 of the OpSpecs or MSpecs is issued to an operator with an approved
carry-on bag program. This paragraph provides details about the operator’s approved carry-on bag program and states whether the operator has a carry-on bag program or a no-carry-on bag program. The FAA will issue this paragraph after reviewing the operator’s carry-on baggage
program in its entirety.
Par 401
e. If an operator chooses to use standard average weights as outlined in this AC, the FAA will document that decision by issuing one or more of the following OpSpecs or MSpecs paragraphs. If an operator proposes to use different average weights (weights other than the standard average or segmented weights) and the FAA concurs with the statistically valid data provided by the operator to support such average weight differences, then those differences will be documented in the following OpSpecs or MSpecs. Although these paragraphs authorize an operator to use average and/or segmented weights, an operator may use actual weights at any time once issued these paragraphs. (1) Paragraph A097Small Cabin Aircraft Passenger and Baggage Weight Program. (2) Paragraph A098Medium Cabin Aircraft Passenger and Baggage Weight Program. (3) Paragraph A099Large Cabin Aircraft Passenger and Baggage Weight Program. NOTE: If an operator does not provide the FAA with adequate information to justify the issuance of one of the above paragraphs that documents the use of standard average, survey-derived average, and/or segmented weights, the FAA may issue paragraph A096, requiring the operator to use actual weights for a specific aircraft or aircraft fleet.
f. If an operator chooses to develop a weight and balance control program using only actual
weights for all the aircraft it operates, the FAA may issue OpSpec/MSpec paragraph A096. The FAA will not issue paragraphs A097, A098, or A099 to operators with a weight and balance
control program that uses only actual weights. The FAA will only issue paragraphs A096, A097, A098, and/or A099 after reviewing the operator’s actual or average weight program.
g. An operator that receives approval to use nonstandard average weights should document
and make available, upon request, the data and methodology used to derive those weights. An operator’s documentation should be sufficiently comprehensive to allow the FAA to reproduce the same results during an audit. An operator should retain this documentation for as long as the
operator uses the nonstandard average weights in its weight and balance control program.
h. If an operator chooses to conduct a survey, the operator will use the results of the survey
to establish a revised average weight and must curtail the loading envelope as necessary. However, if the survey results indicate the average weights are within 2 percent of the standard average weights outlined in this AC, the operator may elect to adopt the standard average
weights only after submitting the survey results to the FAA and receiving approval through its OpSpecs, MSpecs, or LOA.
i. For operators using an onboard weight and balance system to determine the weight and
balance of the aircraft, the FAA will issue OpSpecs or MSpecs paragraph A096. Paragraph A096 documents the use of actual weights and the use of its onboard weight and balance system. For an operator that chooses to use standard average weights as a backup system, the FAA will issues paragraphs A097, A098, or A099, as appropriate. By authorizing the use of average weights, the operator may elect to use actual weights derived from its onboard
Par 402
weight and balance system, and may use average weights as an alternative should the system be inoperative.
j. For operators of all-cargo aircraft, the FAA will issue OpSpecs or MSpecs
paragraph A096. Paragraph A096 documents the use of actual weights, with the exception of flightcrew and flightcrew bag weights. These weights may be accounted for using the standard average weights described in Chapter 3, Table 3-3.
/s/ John Allen for James J. Ballough Director, Flight Standards Service
2. Cargo. As used in this advisory circular (AC), cargo refers to everything carried in the cargo
compartments of the aircraft. This includes bags, mail, freight, express, and company material. It also includes live animals, dangerous goods, and hazardous materials as subcategories of the above.
3. Carry-on bag. A bag that the operator allows the passenger to carry onboard. It should be of
a size and shape that will allow it to be stowed under the passenger seat or in a storage compartment. The operator establishes the exact dimensional limits based on the particular aircraft stowage limits.
4. Certificated weight and CG limits. Weight and center of gravity (CG) limits are established
at the time of aircraft certification. They are specified in the applicable aircraft flight manual
5. Checked bags. Checked bags are those bags placed in the cargo compartment of the aircraft.
This includes bags that are too large to be placed in the cabin of the aircraft or those bags that are
required to be carried in the cargo compartment by regulation, security program, or company policy. For bags checked plane-side, see the definition for plane-side loaded bags.
6. Curtailment. Creating an operational loading envelope that is more restrictive than the
manufacturers’ CG envelope, to assure the aircraft will be operated within limits during all
phases of flight. Curtailment typically accounts for, but is not limited to, in-flight movement, gear and flap movement, cargo variation, fuel density, fuel burn-off, and seating variation.
7. Fleet empty weight. Average operational empty weight (OEW) used for a fleet or group of
aircraft of the same model and configuration.
9. Heavy bags. For this AC, heavy bags are considered any bag that weighs more than
50 pounds but less than 100 pounds. Bags that are 100 pounds or more are considered freight.
10. Large cabin aircraft. Aircraft with a maximum type-certificated seating capacity of 71 or
more passenger seats.
11. Loading envelope. Weight and CG envelope used in a loading schedule. Loading the
aircraft within the loading envelope will maintain the aircraft weight and CG within the manufacturer’s type-certificated limits throughout the flight.
12. Loading schedule.
Method for calculating and documenting aircraft weight and balance
prior to taxiing, to ensure the aircraft will remain within all required weight and balance
limitations throughout the flight.
Manufacturer’s empty weight. Weight of structure, powerplant, furnishings, systems, and
other items of equipment that are an integral part of a particular aircraft configuration. (It is essentially a “dry” weight, including only those fluids contained in closed systems.)
Maximum landing weight. The maximum weight at which the aircraft may normally be
Maximum takeoff weight. The maximum allowable aircraft weight at the start of the
takeoff run.
Maximum taxi weight. The maximum allowable aircraft weight for taxiing.
Maximum zero-fuel weight. The maximum permissible weight of an aircraft with no
disposable fuel and oil.
Medium cabin aircraft. Aircraft with a maximum type-certificated seating capacity
between 70 and 30 passenger seats, inclusive.
Moment. A force that causes or tries to cause an object to rotate.
Onboard weight and balance system. A system that weighs an aircraft and payload, then
computes the CG using equipment onboard the aircraft.
Operational empty weight (OEW). Basic empty weight or fleet empty weight plus
Operational items. Personnel, equipment, and supplies necessary for a particular operation
but not included in basic empty weight. These items may vary for a particular aircraft and may
d. Removable service equipment for cabin, galley, and bar;
23. Passenger assist/comfort animals and devices. These include, but are not limited to,
canes, crutches, walkers, wheelchairs, medically-required animal comfort companions, or animals required to assist the vision impaired.
24. Passenger weight. Passenger weight is the actual weight or the approved average weight of
25. Personal item. Items the operator may allow a passenger to carry aboard, in addition to a
carry-on bag. Typically, an operator may allow one personal item such as a purse, briefcase, computer and case, camera and case, diaper bag, or an item of similar size. Other items, such as
coats, umbrellas, reading material, food for immediate consumption, infant restraining device, and passenger assist/comfort animals and devices, are allowed to be carried on the aircraft and are not counted against the personal item allowance.
26. Plane-side loaded bag. Any bag or item that is placed at the door or steps of an aircraft
and subsequently placed in the aircraft cargo compartment or cargo bin.
27. Reference Balance Arm (BA). The horizontal distance from the reference datum to the CG
28. Segmented Weights. Passenger weights derived by adding a portion of the standard
deviation to an average weight to increase the confidence that the actual weight will not exceed
29. Small cabin aircraft. Aircraft with a maximum type-certificated seating capacity between
5 and 29 passenger seats, inclusive.
30. Standard basic empty weight. Manufacturer’s empty weight plus standard items.
31. Standard items. Equipment and fluids not considered an integral part of a particular
aircraft and not a variation for the same type of aircraft. These items may include, but are not limited to, the following:
APPENDIX 2. SOURCE OF STANDAR