CHAPTER 2. METHODS TO DETERMINE THE WEIGHT OF
PASSENGERS AND BAGS Section 1. Choosing the Appropriate Method
200. What should an operator consider when choosing the appropriate method?
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 2-1 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. For the FAA to recommend that medium cabin aircraft be treated as a large cabin aircraft, the aircraft must meet either (1) both loadability criteria, or (2) the loading schedule criteria. If the aircraft does not meet either of these criteria, then the FAA does not recommend that the operator be allowed to use large cabin aircraft measures. Instead, the aircraft should be subject to the small cabin aircraft methods outlined in paragraph 200f.
(1) Loadability criteria.
• The CG of the OEW is within the manufacturer’s loading envelope
• 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 Par 200 Page 15
(2) Loading schedule criteria.
• The operator must use a loading schedule based upon zones
• The aircraft cabin may have no more than four rows of seats per zone with not less than 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.
(1) The operator may use actual passenger and bag weights, or
(2) The operator may use segmented passenger weights (see Section 4) and bag weights prescribed for large cabin aircraft, or
(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 the aircraft has equivalent part 23 commuter category or part 29 performance data), and
(b) The operator applies the additional curtailments as prescribed in Appendix 4.
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Section 2. Standard Average Weights
201. What standard average passenger weights should an operator use with an approved carry-on bag program?
a. The standard average passenger weights provided in Table 2-1 were established based on data from U.S. Government health agency surveys. For more background information on the source of these weights, refer to Appendix 2.
b. The standard average passenger weights in Table 2-1 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.
TABLE 2-1. STANDARD AVERAGE PASSENGER WEIGHTS Standard Average Passenger Weight Weight Per Passenger Summer Weights Average adult passenger weight 190 lb Average adult male passenger weight 200 lb Average adult female passenger weight 179 lb Child weight (2 years to less than 13 years of age) 82 lb
Winter Weights Average adult passenger weight 195 lb Average adult male passenger weight 205 lb Average adult female passenger weight 184 lb Child weight (2 years to less than 13 years of age) 87 lb
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 2-1 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 205 of this section.
NOTE: The weight of children under the age of 2 has been factored into the standard average and segmented adult passenger weights.
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202. What standard average weights should an operator use for carry-on bags and personal items?
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 2-1 include a 16-pound allowance for personal items and carry-on bags, based on the assumption that—
(1) One-third of passengers carry one personal item and one carry-on bag.
(2) One-third of passengers carry one personal item or carry-on bag.
(3) One-third of passengers carry neither a personal item nor a carry-on bag.
(4) The average weight allowance of a personal item or a carry-on bag is 16 pounds.
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 202a are inconsistent 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.
NOTE: Operators using an approved carry-on baggage program should refer to AC 121-29, Carry-On Baggage, current edition, for information regarding carry-on baggage.
203. What standard average weights should an operator use for checked bags?
An operator that chooses to use standard average weights for checked bags should use a standard average weight of at least 30 pounds. An operator that requests approval to use a standard average weight of less than 30 pounds for checked bags should have current, valid survey data to support a lesser weight. An operator also may conduct a study to establish different standard average bag weights for portions of its operation to account for regional, seasonal, demographic, aircraft, or route variation. For example, an operator could establish different standard average bag weights for domestic and international routes.
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:
(1) A standard average weight of 60 pounds,
(2) An average weight based on the results of a survey of heavy bags, or
(3) The actual weight of the heavy bag.
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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.
c. Plane-Side Loaded and Checked Bags. Part 91, subpart K of part 91, and part 135 ondemand operations using standard average bag weights should consider all bags not stored in the cabin as checked bags. However, operators may develop procedures for identifying bags that would typically be considered carry-on and/or plane-side loaded baggage and incorporate such average weights into their approved carry-on and weight and balance control program. If such procedures are developed, the operator may use the standard average weights specified for carryon, plane-side loaded, and checked baggage. Operators conducting flights under parts 91 and 135 in which all passenger bags are typically loaded plane-side or all bags are carried into the cabin for further storage, should develop guidelines to inform pilots when it is appropriate to use the heavier standard average checked bag weights, heavy bag weights, or actual weights. In no case should an operator only use plane-side loaded standard average weights for all baggage loaded plane-side.
204. What standard average weight should an operator of large cabin aircraft use for bags checked plane-side?
Operators with a carry-on bag program that use standard average weights should account for the weight of each carry-on bag checked plane-side as 30 pounds. An operator may request approval to use a weight other than 30 pounds if the operator has current, valid survey data to support a different average weight for plane-side loaded bags.
205. What standard average weights should an operator of small and medium cabin aircraft use, if it has a “no-carry-on bag program?”
NOTE: A no-carry-on bag program is limited to small and medium cabin aircraft (including medium cabin aircraft treated as a large cabin aircraft).
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 203 and 204 above. Furthermore, the passenger weight credit Par 203 Page 19
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 2-2.
TABLE 2-2. AVERAGE PASSENGER WEIGHTS FOR OPERATORS WITH A
NO-CARRY-ON BAG PROGRAM Average Passenger Weight Weight Per Passenger Summer Weights Average passenger weight 184 lb Average male passenger weight 194 lb Average female passenger weight 173 lb Child weight (2 years to less than 13 years of age) 76 lb
Winter Weights Average passenger weight 189 lb Average male passenger weight 199 lb Average female passenger weight 178 lb Child weight (2 years to less than 13 years of age) 81 lb
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.
NOTE: Part 91, subpart K of part 91, and on-demand operations using standard average bag weights should consider all bags not stored in the cabin as checked bags (reference paragraph 203) unless the operator develops procedures for identifying bags that would typically be considered carry-on/plane-side loaded and/or traditional checked baggage.
206. What are the standard average weights for crewmembers?
a. An operator may choose to use the standard crewmember weights shown in Table 2-3 or conduct a survey to establish average crewmember weights appropriate for its operation.
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TABLE 2-3. STANDARD CREWMEMBER WEIGHTS Crewmember Average Weight Average Weight with Bags Flight crewmember 190 lb 240 lb Flight attendant 170 lb 210 lb Male flight attendant 180 lb 220 lb Female flight attendant 160 lb 200 lb Crewmember roller bag 30 lb NA Pilot flight bag 20 lb NA Flight attendant kit 10 lb NA
b. The flight crewmember weights provided in Table 2-3 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 provided in Table 2-3 were derived from the 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.
207. What weights may be used for company materials, freight, and mail?
a. Company Materials and Freight. An operator should use actual weights for company materials, aircraft parts, and freight carried aboard an aircraft.
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.
208. What are the standard average weights for special passenger groups that do not fit an operator’s standard average weight profile?
a. Actual passenger weights should be used for nonstandard weight groups (sports teams, etc.) unless average weights have been established for such groups by conducting a survey in accordance with the procedures established in Section 3 of this chapter. When such groups form only a part of the total passenger load, actual weights, or established average weights for the nonstandard group, may be used for such exception groups and average weights used for the balance of the passenger load. In such instances, a notation should be made in the load manifest indicating the number of persons in the special group and identifying the group; e.g., football squad, etc.
b. Roster weights may be used for determining the actual passenger weight.
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c. 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.
d. 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-pound per bag allocation.
e. Actual weights must be used in cases where the carry-on bags are not representative of the operator’s profile.
f. Groups that are predominantly male or female should use the standard average weights for males or females provided in Table 2-1.
g. For 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 Title 32 of the Code of Federal Regulations part 861, section 861.4(e)(3)(ix), current edition). 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.
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Section 3. Average Weights Based on Survey Results
209. What should an operator consider when designing a survey?
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 consider—
(1) The sample size required to achieve the desired reliability,
(2) The sample selection process, and
(3) The type of survey (average weights or a count of items).
210. What sample sizes should an operator use?
Several factors must be considered when determining an adequate sample size. The more varied the population, the larger the sample size required to obtain a reliable estimate. Paragraph 211 provides a formula to derive the absolute minimum sample size to achieve a 95-percent confidence level. Table 2-4 has been provided for those operators that wish to use calculations other than those listed in paragraph 211. Table 2-4 provides the operator with an acceptable number of samples that may be collected to obtain a 95-percent confidence level and lists the tolerable error associated with each category.
TABLE 2-4. MINIMUM SAMPLE SIZES Survey Subject Minimum Sample Size Tolerable Error Adult (standard adult/male/female) 2,700 1% Child 2,700 2% Checked bags 1,400 2% Heavy bag 1,400 2% Plane-side loaded bags 1,400 2% Personal items and carry-on bags 1,400 2% Personal items only (for operators with a no carry-on bag program) 1,400 2%
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211. When conducting a survey, can an operator collect a smaller sample size than that published in Table 2-4?
If the operator has chosen to use a sample size that is smaller than that provided in Table 2-4, the operator should collect a sufficient number of samples to satisfy the following formulas:
average sample theisx ghtssurvey wei individual theisx surveyed points ofnumber theisn deviationstandardtheis s :
1 )( _ j 2 1 _ Where n xx s n j j − − = ∑ =
percentageerror tolerable theis :
* 100**96.1 _ e Where xn se =
212. What sampling method should an operator use?
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 line 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 Page 24 Par 211
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.
213. What should an operator consider when developing a survey plan and submitting it to the FAA?
a. Developing a Survey Plan. Before conducting a survey, an operator should develop a survey plan. The plan should describe the dates, times, and locations the survey will take place.
In developing a survey plan, the operator should consider its type of operation, hours of operation, markets served, and frequency of flights on particular routes. An operator should avoid conducting surveys on holidays unless it has a valid reason to request the particular date.
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.
214. What general survey procedures should an operator use?
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.
c. Weighing Bags. When weighing bags on a particular flight, an operator should take care to ensure that it is properly accounting for all items taken aboard the aircraft.
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