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 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.
314. 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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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.
e. Surveys for particular routes. An operator may conduct a survey for a particular route if the operator believes that the average weights on that route may differ from those in the rest of its operations. To establish a standard average passenger weight along the route, an operator may survey passengers at only one location. However, an operator should conduct surveys of personal items and bags at the departure and arrival locations, unless the operator can verify there is no significant difference in the weight and number of bags in either direction along the route.
315. What information might an operator gain from conducting a count survey?
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—
(1) Fifty percent of passengers carry one carry-on bag and one personal item.
(2) Thirty percent of passengers carry one carry-on bag or one personal item.
(3) Twenty percent of passengers carry neither a carry-on bag nor a personal item.
(4) The survey results show that the average passenger carries approximately 21 pounds of personal items and carry-on bags rather than the standard allowance of 16 pounds. In such a case, it would be irresponsible for the operator to fail to increase the standard average weights for that route(s) by 5 pounds per passenger.
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 Page 30 Par 314
316. When should an operator conduct another survey to revalidate the data from an earlier survey?
In order to use survey-derived average weights, an operator must revalidate such survey data every 36 calendar-months or revert to the standard average weights, provided the new survey average weight results are within 2 percent of the standard average weights listed in this AC.
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Section 4. Segmented Passenger Weights
317. What should an operator consider when using segmented weights?
a. 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.
TABLE 3-5. SEGMENTED WEIGHTS FOR ADULT PASSENGERS (IN POUNDS;
SUMMER) Ratio of Male to Female Passengers Maximum Certificated Passenger Seating Capacity 0/100 10/90 20/80 30/70 40/60 50/50 60/40 70/30 80/20 90/10 100/0 1 to 4 Use actual weights, or asked (volunteered) weights plus 10 lb 5 231 233 235 237 239 241 243 245 247 249 251 6 to 8 219 221 223 225 227 229 231 233 235 237 239 9 to 11 209 211 213 215 217 219 221 223 225 227 229 12 to 16 203 205 207 209 211 213 215 217 219 221 223 17 to 25 198 200 202 204 206 208 210 212 214 216 218 26 to 30 194 196 198 200 202 204 206 208 210 212 214 31 to 53 191 193 195 197 199 201 203 205 207 209 211 54 to 70 188 190 192 194 196 198 200 202 204 206 208
b. An operator may make the following adjustments to the table above:
(1) An operator may subtract 6 pounds from the passenger weight outlined above if it has a no-carry-on bag program or does not allow any carry-on baggage into the cabin of the aircraft.
(2) An operator should add 5 pounds to the weights above during the winter season.
c. 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.
d. 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.
318. How are loading envelope curtailment and bag weight affected by an operator’s use of segmented weights?
a. Loading envelope curtailment. An operator using segmented passenger weights should consider curtailing its operational loading envelope using the methods described in Appendix 4.
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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 nocarry-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.
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Section 5. Actual Weight Programs
320. If the operator decides to use an actual weights program, how might it determine the actual weight of passengers?
An operator may determine the actual weight of passengers by—
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.
NOTE: If an operator believes that the weight volunteered by a passenger is understated, the operator should make a reasonable estimate of the passenger’s actual weight and add 10 pounds.
321. If the operator decides to use an actual weight program, how should it determine the actual weights of personal items and bags?
To determine the actual weight of a personal item, carry-on bag, checked bag, plane-side loaded bag, or a heavy bag, an operator should weigh the item on a scale.
322. What approach should an operator use to record actual weights?
An operator using actual weights should record all weights used in the load buildup.
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CHAPTER 4. OPERATOR REPORTING SYSTEMS AND FAA OVERSIGHT Section 1. Pilot and Agent Reporting Systems
400. What are the pilots’ and operators’ responsibilities in reporting aircraft loading and manifest preparation discrepancies?
Each operator should develop a reporting system and encourage employees to report any discrepancies in aircraft loading or manifest preparation. These discrepancies may include errors in documentation or calculation, or issues with aircraft performance and handling qualities that indicate the aircraft weight or balance is not accurate. Operators should attempt to determine the cause of each discrepancy and take appropriate corrective action. This would include a load audit on affected flights or conducting a passenger or bag weight survey in accordance with this AC if trends indicate it is warranted.
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Section 2. FAA Oversight
401. Which FAA inspectors are responsible for overseeing an operator’s weight and balance program?
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.
402. Which portions of OpSpecs or MSpecs are relevant to an operator’s weight and balance program?
a. This AC details methods to develop a weight and balance control program with greater accuracy and increased flexibility. By changing its OpSpecs or MSpecs, an operator may alter the weights used in its weight and balance control program to include appropriate combinations of standard average weights, average weights based on survey results, or actual weights.
b. Parts A and E of OpSpecs or MSpecs authorize an operator’s weight and balance control program. These parts will address—
(1) Average passenger and bag weights;
(2) Situations when the use of average weights is inappropriate;
(3) The treatment of charter flights or special groups, if applicable;
(4) The type of loading schedule and instructions for its use;
(5) Aircraft weighing schedules; and
(6) Other procedures that the operator may require to assure control of weight and balance.
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.
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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 A097Small Cabin Aircraft Passenger and Baggage Weight Program.
(2) Paragraph A098Medium Cabin Aircraft Passenger and Baggage Weight Program.
(3) Paragraph A099Large 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 Page 37
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.
403. When will the FAA revise the standard average weights in this AC?
The FAA will periodically review the standard average passenger weights listed in this AC, after the release of a new NHANES. If the FAA finds that the data from NHANES indicates a weight change of more than 2 percent, the FAA will revise this AC to update the standard average weights.
/s/ John Allen for James J. Ballough Director, Flight Standards Service Page 38 Par 402
Appendix 1 APPENDIX 1. DEFINITIONS
1. Basic empty weight. The aircraft empty weight, adjusted for variations in standard items.
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 (AFM).
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.
8. Freight. Cargo carried for hire in the cargo compartment that is not mail or passenger bags.
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.
Appendix 1
13. 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.)
14. Maximum landing weight. The maximum weight at which the aircraft may normally be landed.
15. Maximum takeoff weight. The maximum allowable aircraft weight at the start of the takeoff run.
16. Maximum taxi weight. The maximum allowable aircraft weight for taxiing.
17. Maximum zero-fuel weight. The maximum permissible weight of an aircraft with no disposable fuel and oil.
18. Medium cabin aircraft. Aircraft with a maximum type-certificated seating capacity between 70 and 30 passenger seats, inclusive.
19. Moment. A force that causes or tries to cause an object to rotate.
20. Onboard weight and balance system. A system that weighs an aircraft and payload, then computes the CG using equipment onboard the aircraft.
21. Operational empty weight (OEW). Basic empty weight or fleet empty weight plus operational items.
22. 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 include, but are not limited to, the following:
a. Crewmembers, supernumeraries, and bags;
b. Manuals and navigation equipment;
c. Passenger service equipment, including pillows, blankets, and magazines;
d. Removable service equipment for cabin, galley, and bar;
e. Food and beverage, including liquor;
f. Usable fluids, other than those in useful load;
g. Required emergency equipment for all flights;
h. Life rafts, life vests, and emergency transmitters;
i. Aircraft unit load devices;
j. Potable water;