b. Multiple Categories. For airplanes certified in more than one category, § 23.1541(c)(2) requires all of the placard and marking information to be furnished in the AFM.
This practice is encouraged for all airplanes.
c. Powerplant Instruments. AC 20-88A provides additional guidance on the marking of powerplant instruments.
2. § 23.1543 Instrument Markings: General. AC 20-88A provides guidance on the marking of powerplant instruments.
3. § 23.1545 Airspeed Indicator. This regulation is self-explanatory.
4. § 23.1547 Magnetic Direction Indicator. This regulation is self-explanatory.
5. § 23.1549 Powerplant Instruments. This subject is covered in AC 20-88A.
6. § 23.1551 Oil Quantity Indicator. Reserved.
7. § 23.1553 Fuel Quantity Indicator. Reserved.
8. § 23.1555 Control Markings.
a. Examples of Emergency Controls.
(1) Reciprocating engine mixture controls and turbine engine condition levers.
Reciprocating engine mixture controls and turbine engine condition levers incorporating fuel stopcocks or fuel stopcocks themselves are considered to be emergency controls, since they provide an immediate means to stop engine combustion.
(2) Quick-disconnect/interrupt switch. Quick-disconnect/inte rrupt switch of an electric trim system.
b. Requirements. Section 23.1555(e)(2) covers the requirements for emergency controls.
9. § 23.1557 Miscellaneous Markings and Placards. Reserved.
10. § 23.1559 Operating Limitations Placard. Reserved.
11. § 23.1561 Safety Equipment.
a. Examples of Safety Equipment. Safety equipment includes such items as life rafts, flares, fire extinguishers, and emergency signaling devices.
b. Requirements. Sections 23.1411 through 23.1419 cove r the requirements for safety equipment.
12. § 23.1563 Airspeed Placards. This regulation is self-explanatory.
13. § 23.1567 Flight Maneuver Placard. This regulation is self-explanatory.
Section 3. Airplane Flight Manual and Approved Manual Material
1. § 23.1581 General.
a. GAMA Specification No. 1. General Aviation Manufacturers Association (GAMA) Specification No. 1, Revision No. 1, dated September 1, 1984, provides broad guidance for contents of a Pilot's Operating Handbook (POH) that will fulfill the requirements of an AFM, for certain airplanes under 6,000 pounds, if the POH meets all of the requirements of §§ 23.1581 through 23.1589. There is no objec tion to the title, "Pilot's Operating Handbook," if the title page also includes a statement indicating that the document is the required AFM and is approved by the FAA.
b. Optional Presentations. Beginning with amendment 23-21, applicants are provided with an option for the presentation of the required procedures, performance, and loading information. The regulatory requirements of the two options are given in §§ 23.1581(b)(1) and
23.1581(b)(2). The options are as follows:
(1) Section 23.1581(b)(1). The AFM must have approved limitations, procedures, performance, and loading sections. These approved sections must be segregated, identified, and clearly distinguished from unapproved information furnished by the applicant if any unapproved information is furnished. Normally, FAA approval is indicated by the signature of the FAA Administrator, or appointed representative, on the cover page and a page effectivity table so that it is clear to the operational pilot exactly which pages are applicable and the date of approval.
(2) Section 23.1581(b)(2). The AFM must have an approved limitations section and this approved section must contain only limitations (no procedures, performance, or loading information allowed). The limitations section must be identified and clearly distinguished from other parts of the AFM. The remainder of the manual may contain a mixture of approved and unapproved information, without segregation or identification. However, the other required material (procedures, performance, and loading information) must be determined in accordance with the applicable requirements of part 23. The meaning of "acceptable," as used in § 23.1581(b)(2)(ii), is given in the preamble to amendment 23-21. The applicable portion of the amendment 23-21 preamble is as follows:
"In finding that a manual is acceptable, the FAA would review the manual to determine that the required information is complete and accurate. The manual would also be reviewed to ensure that any additional information provided by the applicant is not in conflict with required information or contrary to the applicable airworthiness requirements."
(A) The indication of approval for the approved section should be as discussed in the preceding paragraph, paragraph (1). GAM A Specification No. 1 has been found to comply with the provisions of § 23.1581(b)(2).
c. Part 36 Noise Limitations or Procedures.
(1) Section 23.1581(b)(1). If the applicant chooses the § 23.1581(b)(1) option, operating limitations required by part 36 should be placed in the operating limitations portion of the AFM. Any part 36 procedures should be pl aced in the operating procedures portion of the AFM.
(2) Section 23.1581(b)(2). If the applicant chooses the § 23.1581(b)(2) option, the approved AFM should contain the following approved, but separate, portions:
(i) Operating limitations prescribed in § 23.1583. Note that § 23.1581(b)(2)(i) limits the information in this portion to that prescribed in § 23.1583. Since the present part 36 limitation is a weight limitation, the part 36 limitation may be included.
(ii) Operating procedures prescribed by part 36. Section 23.1581(a) requires part 36 procedures to be approved.
d. STC Procedures.
(1) AFM Options. STC applicants are responsible for preparing an AFM supplement when the airplane has been modified in such a manner that limitations, procedures, or performance has been changed. The supplement should be prepared in accordance with the guide provided in Appendix 5 and reflect the necessary supplemental information. Alternately, the applicant may choose to prepare a new AFM. If the applicant selects the latter option, the new AFM replaces the original AFM in its entirety.
(2) Performance. If the STC applicant does not want credit for any increased performance and demonstrates that the performance meets or exceeds all basic airplane performance, a general statement to that effect would be satisfactory. Some STC's that meet or exceed all performance requirements may also increase the fuel consumption reducing endurance. Applicants should a dd a note or change the performance information for endurance that clearly indicates this decrease to the pilot.
e. Additional Information. Some additional information items that are required for safe operation because of unusual design, operating, or handling characteristics are as follows:
(1) Strobe lights. Operation of strobe lights during flight through fog, clouds, or flying closely under an overcast;
(2) Carburetor heat. Use of carburetor heat;
(3) Flaps. Restricted use of flaps during sideslips;
(4) Propeller pitch. Management of propeller pitch when Beta Range is provided;
(5) Sand screens and engine heaters. Procedures for the temporary use of sand screens and engine heater devices;
(6) Feathering. Unusual feathering design where propeller will not feather with throttle closed;
(7) Fuel flow. Scheduling for fuel flow by e ngine mixture leaning procedure;
(8) Spin recovery. Unusual spin recovery techniques;
(9) Wheelbarrowing. Wheelbarrowing characteristics;
(10) Oscillations. Pilot-induced oscillations or os cillations caused by turbulence, particularly on swept-wing airplanes;
(11) Depressurization. Depressurization proced ures prior to landing;
(12) Automatic devices. Procedures for operation of automatic devices; that is, wing levelers, Mach trim, yaw damper, and so forth; and
(13) Flight guidance and control systems. Procedures for operation of integrated flight guidance and control systems. This should include proper pilot response to cockpit warnings, diagnosis of system failures, discussion of possible pilot-induced flight control system problems, and use of the system in a safe manner.
(14) Turbochargers. Procedures for normal operation, if appropriate, and abnormal and emergency operations.
2. § 23.1583 Operating Limitations.
a. Limitations Section. The purpose of the limitations section is to present the limitations applicable to the airplane model by serial number, if applicable, as established in the course of the type certification process in determining compliance with parts 23 and 36. The limitations should be presented without explanation other than those explanations prescribed in parts 23 and 36. The operating lim itations contained in the limitations section (including any noise limited weights) should be expressed in mandatory, not permissive, language. The terminology used in the AFM should be consistent with the relevant regulatory language.
b. GAMA Specification. GAMA Specification No. 1, Revision No. 1 dated September 1, 1984, section 2, provides guidance for the contents of the limitations section.
Additional guidance is provided below for "Kinds of Operation," "Fuel Limitations," and "Commuter Category."
c. Kinds of Operation Equipment List (KOEL). The KOEL is to be placed in the limitations section of the AFM since the KOEL items form part of the limitations applicable to airplane operation. The sample KOEL given in Appendix 6 lists systems and equipment for a specific airplane in an acceptable format. Although the sample KOEL may contain items that are not applicable to all airplanes, it may be used as a guide.
(1) Standardization. Although there is no specific fo rmat required for the KOEL, we recommend, in the interest of standardization, that the KOEL be placed in columns and each item of equipment required for a specific type of operation for which the airplane is approved be noted in the appropriate column. Regardless of the format used, the KOEL should provide for:
(i) The kinds of operation for which the airplane was type certificated (that is, day or night VFR, day or night IFR, and icing conditions).
(ii) The identity of the systems and equipment upon which type certification for each kind of operation was predicated and must be installed and operable for the particular kind of operation indicated. Systems and equipment necessary for certifi cation includes those:
(A) required under the basic airworthiness requirements;
(B) required by the operating rules;
(C) required by special conditions;
(D) required to substantiate equivalent safety findings;
(E) required by airworthiness directives (AD); and (F) either items of equipment or systems not specifically required under items
(i) through (v) of this paragraph, but used by the applicant in order to show compliance with the regulations.
(2) The KOEL should not:
(i) Contain those obvious components required for the airplane to be airworthy, such as wings, empennage, engines, landing gear, brakes, and so forth.
(ii) Contain an exceptions column.
d. Fuel Limitations. The fuel limitations information in GAMA Specification 1 may not be applicable, depending on the airplane certification basis.
e. Turbine Airplanes and Commuter Category Airplanes. For those performance weight limits that may vary with runway length, altitude, temperature, and other variables, the 166
variation in weight limitation may be presented as graphs in the performance section of the manual and included as limitations by specific reference in the limitations section of the AFM.
3. § 23.1585 Operating Procedures.
a. Explanation. Refer to GAMA Specification 1.
b. Electronic Checklist Displays.
(1) Background. Checklists, both hard copy and electronic displays, are a method used by manufacturers to provide (in part) the normal and emergency operating procedures required by § 23.1585. Section 23.1581 is also a pplicable for the manner and format of presentation.
(2) Display Content. For those airplanes with appr oved AFMs, the wide variety of configurations and corresponding flight manual supplements within a single model may establish a virtually unique set of checklist procedures for each individual airplane. The responsibility for electronic checklist display contents rests with the operator. A hard copy of the AFM should be available to the operator for reference.
(3) AFM Changes. Incorporation of STC’s could n ecessitate changes to the flight manual, flight manual supplements, or addition of new supplements. These supplements could require revision to the checklist for that particular airplane. Such changes should be made by the operator.
(4) Operator Revisions. Although it is not necessary for equipment manufacturers to store electronic checklist data in such a manner that it cannot be changed in the field, some equipment manufacturers have chosen to program checklist data in a manner that prevents field alternation. The operator would be responsible for ensuring the checklist data is revised as necessary upon installation of new/different equipment.
(5) Disclaimers. Electronic checklists are usually displayed on the same MFD as other electronic displays. Cert ain disclaimer statements may be appropriate. Presentation of a disclaimer statement each time the equipment is turned on will provide adequate notification to the pilot. This disclaim er should include statements that clearly state:
(i) Contents of the checklists are the responsibility of the operator
(ii) The approved AFM takes precedence and, for completeness, should be referred to as the primary information source.
(iii) The electronic checklist may not contain all the notes, cautions, and warnings associated with a procedure.
(6) Automatic Display. Automatic display of ap propriate checklists during conditions of engine failure, generator failure, and so forth, will require a review based upon the 167
specific application involved. Approval of the checklist content, malfunction prioritization, and operation is required.
4. § 23.1587 Performance Information.
a. Performance Information. This section contains the airworthiness performance information necessary for operation in compliance with applicable performance requirements of part 23, applicable special conditions, and data required by part 36. Additional information and data essential for implementing special operational requirements may be included. Performance information and data should be presented for the range of weight, altitude, temperature, airplane configurations, thrust rating, and any other operational variables stated for the airplane. This information should include a discussion of icing operations, loss of performance possible, and any information to aid in recognition of icing conditions that may exceed the certificated capabilities of the aircraft ice protection systems.
b. Normal, Utility, and Acrobatic Category Airplanes. Refer to GAMA Specification 1.
c. Turbine Airplanes and Commuter Category Airplanes.
(1) General. Include all descriptive informati on necessary to identify the precise configuration and conditions for which the performance data are applicable. Such information should include the complete model designations of airplane and engines, the approved flap, sweep, or canard settings, definition of installed airplane features and equipment that affect performance, together with the operative status thereof (for example, antiskid devices, automatic spoilers, and so forth). This section should also include definitions of terms used in the performance section (that is, IAS, CAS, ISA, configuration, net takeoff flight path, icing conditions, and so forth), plus calibration data for airspeed (flight and ground), Mach number, altimeter, ambient air temperature, and other pertinent information.
(2) Performance Procedures. The procedures, techniques, and other conditions associated with attainment of the flight manual performance data should be included.
Performance procedures may be presented as a performance subsection or in connection with a particular performance graph. In the latter case, a comprehensive listing of the conditions associated with the particular performance may serve the objective of "procedures" if sufficiently complete.
(3) Thrust or Power Setting. Thrust or power settings s hould be provided for at least takeoff and maximum continuous and the methods required to obtain the performance shown in the AFM. If appropriate, these data may be require d to be shown for more than one thrust setting parameter.
(4) Takeoff Speeds. The operational takeoff speeds V 1, VR, and V2 should be presented together with associated conditions. Section 23.1587(d)(10) requires the speeds be given in CAS. Since the flightcr ew flies IAS, the airspeeds should also be presented in IAS.
The V1 and VR speeds should be based upon "ground effect" calibration data; the V2 speeds should be based upon "free air" calibration data.
(5) Takeoff Distance. Takeoff distance should be shown in compliance with § 23.59.
(6) Climb Limited Takeoff Weight. The climb limited takeoff weight, that is the most limiting weight showing compliance with § 23.67, should be provided.
(7) Miscellaneous Takeoff Weight Limits. Takeoff weight limits, for any equipment or characteristic of the airplane configuration which imposes an additional takeoff weight restriction, should be shown (that is, tire speed limitations, brake energy limitations, and so forth).
(8) Takeoff Climb Performance. For the prescribed takeoff climb airplane configurations, the climb gradients should be presented together with associated conditions. The scheduled climb speed(s) should be included.
(9) Takeoff Flight Path Data. The takeoff flight paths of § 23.61 or performance information necessary to enable construction of such paths, together with associated conditions (that is, procedures, speed schedules), should be presented for the configurations and flight path segments existing between the end of the prescribed takeoff distance and the point of attaining the en route climb configuration airspeed or 1500 feet, whichever is higher.
(10) En Route Climb Data. The climb gradients prescribed in § 23.67 should be presented together with associated conditions, including the speed schedule used.
(11) Balked Landing Climb Limited Landing Weight. The climb limited landing weight that is the most limiting weight showing compliance with § 23.77.
(12) Approach Climb Limited Landing Weight. The climb gradient determined in § 23.67(e)(3) should be presented. The required climb gradient may limit the landing weight.
(13) Landing Approach Speeds. The scheduled speeds associated with the approved landing distances should be presented together with associated conditions.
(14) Landing Distance. The landing distance from a height of 50 feet should be presented together with associated ambient temperature, altitude, wind conditions, and weights up to the maximum landing weight. Operational landing distance data should be presented for smooth, dry, and hard-surfaced runways. At the option of the applicant, with concurrence by the FAA, additional data may be presented for wet or contaminated runways and for other than smooth, hard-surfaced runways.
(15) Headwinds/Tailwinds. Where specified within § 23.1587, the effect of headwinds and tailwinds must be defined. When the performance gradient is positive, use 50 percent of the headwind component and 150 percent of the tailwind component. When the 169
performance gradient is negative, use 150 percent of the headwind component and 50 percent of the tailwind component.
5. § 23.1589 Loading Information. Refer to GAMA specification 1.
Appendix 1. Power Available
1. General. The purpose of this appendix is to provide guidance regarding the power considerations for various kinds of powerplants. The power output of each airplane/engine configuration requires special considerations when determining test day performance corrections and providing the performance expansions for the AFM. The types of powerplants discussed in this appendix are:
a. Reciprocating Engines.
(1) Normally aspirated engine with a fixed pitch propeller;
(2) Normally aspirated engine with a constant speed propeller; and
(3) Turbocharged engine with a constant speed propeller.
b. Turbopropeller Engines.
2. Reciprocating Engines.
a. Power Charts. The horsepower being developed by reciprocating engines is usually identified by horsepower charts that are provided by the engine manufacturer. These charts are developed from results of ground runs using a brake-type dynamometer in a test facility and may have no direct correlation to any particular airplane or flight condition. The variations of power with altitude and temperature are the result of theoretical relationships involving air density, fuel/air ratios, and so forth. These charts nearly always assume a “b est power” fuel to air ratio that can rarely be consistently used in service under normal operating conditions. Many installations, for example, intentionally use fuel to air ratios that are on the fuel-rich side of best power so that the engine will not overheat. Providing sufficient cooling airflow ov er each cylinder to ensure adequate cooling may be more difficult than cooling with a rich fuel mixture. These horsepower charts were also developed while maintaining a constant temperature on each cylinder. This is not possible in service. The charts are developed assuming the following:
(1) There is no ram airflow due to movement through the air; or
(2) There are not losses due to pressure drops resulting from intake and air filter design; or
(3) There are no accessory losses.
b. Chart Assumptions. Regardless of the test stand conditions that are not duplicated in service, it is necessary to assume that each given pressure altitude temperature, engine speed, and manifold pressure combination will result in horsepower that can be determined from the engine power chart.
To accomplish this requires certain procedures and considerations.
c. Tolerances. Each engine power chart specifies a horsepower tolerance from rated horsepower.
These are commonly ±2 ½ percent, +5 percent, -2 percent, or +5 percent, -0 percent. This means that with all the variables affecting power being held constant (that is, constant manifold pressure, engine speed, temperature, and fuel to air ratio), the power could vary this much from engine to engine. For this reason, it is appropriate to account for these variations. Calibration of the test engine(s) by the engine manufacturer is one way to accomplishing this. During engine calibration, the test engine is run on a test stand at the engine manufacturer’s facility to identify how it compares with the power A1-1
output at conditions under which it was rated. The result is a single point comparison to the rated horsepower.
d. Test Day Power.
(1) Calibrated Engines. If an engine, for example, is rated at 200 BHP, the calibration results might show the particular serial numbered engine to develop 198.6 BHP. This is 0.7 percent below the rated power. For this engine, each of the horsepower values obtained from the engine manufacturer’s chart should be adjusted downward by 0.7 percent to obtain test day horsepower.
(2) Uncalibrated Engines. If the engine is not calibrated, an acceptable method of accounting for the unknown factors is to assume that the test engine is putting out rated horsepower plus the plus tolerance. For example, if the rated horsepower was 350 and the tolerance was ±2 ½ percent, test day sea level chart horsepower would be assumed to be 350 + .025 (350), or 358.8.
(3) Humidity. Section 23.45(e) requires performance to be based on 80 percent relative humidity on a standard day. Experience has shown that conditions such as 80 percent relative humidity on a standard day at sea level have a very small effect on engine power because this condition results in a very low specific humidity. The engine is affected directly by specific humidity (pounds of water per pounds of air) rather than relative humidity. For test day power, dry air should be assumed unless the applicant has an approved method for measuring and determining the effect of humidity.
e. Chart Brake Horsepower. A chart brake horsepower (BHPc) should be determined for expansion of the flight test data in the AFM. BHPc is the horsepower at a particular pressure altitude, manifold pressure and r.p.m. Appropriate inlet temperature corrections should be applied, in accordance with the manufacturer’s engine power chart. An 80 percent relative humidity correction should be applied if the engine manufacturer has an acceptable method and the correction is significant.
f. Variations in Methods. Peculiarities of the various types of reciprocating engines require special considerations or procedures to determine installed power. These procedures are discussed in subsequent paragraphs.
3. Normally Aspirated Engines with Constant Speed Propellers.
a. Manifold Pressure Versus Altitude. As a first step to determine installed horsepower, flight tests should be conducted to determine manifold pressure versus pressure altitude for the engine installation. The test manifold pressures would be compared to the engine manufacturer’s chart values, as shown on Figure A1-1. Figure A1-1 shows an example of test manifold pressure and chart manifold pressures versus pressure altitude. In this example, the observed manifold pressures are lower than the chart values. This means that the induction system pressure losses exceed the ram pressure rise. An induction system in which manifold pressures exceed the zero ram chart values would reflect an efficient induction system. The term chart brake horsepower indicates that the horsepower values have yet to be corrected for inlet temperature conditions.
b. Example Calculation. The overall corrections to determine installed test day brake horsepower and chart brake horsepower (BHPc) to be used in the expansion of performance would be as follows (refer to Figure A1-1):
A1-2
~- ~- Known: Pressure Altitude..............................................................4,000 feet Manifold Pressure............................................................24.9 in Hg.
Outside Air Temperature.................................................+55 ºF Inlet Temperature............................................................+63 ºF
Engine Speed...................................................................2,650 r.p.m.
Engine Calibration...........................................................-0.7 % Engine Tolerance.............................................................±2 ½ %
Calculated Test Day BHP for a Calibrated Engine:
Standard Temperature @ 4,000 ft.....................................................44.7 ºF Installed Chart Brake Horsepower....................................................335 BHP (from Figure A1-1) Engine Calibration Correction = (335)(-.007)...................................-2.3 BHP Correcting for Inlet Temperature 460 44.7Test Day BHP = (335-2.3) ........................................326.8 BHP 460 63.0 Calculated Test Day BHP for an Uncalibrated Engine:
Standard Temperature @ 4,000 ft.....................................................44.7 ºF Installed Chart Brake Horsepower....................................................335 BHP (from Figure A1-1) 460 44.7Test Day BHP =[335 + .025(335)] ............................337.3 BHP 460 63 Calculated BHPc for Test Day Density Altitude (Hd):
Hd at 4,000 ft. and 55 ºF..................................................................4,670 ft.
Installed BHPc (from Figure A1-1)........................................................326 BHP Standard Temperature at 4,670 ft.....................................................42 ºF Correcting for Inlet Temperature Rise 460 42BHPc = 326 ........................................................323.4 BHP 460 42 8 A1-3