AC 29.1549B. § 29.1549 (AMENDMENT 29-59) POWERPLANT INSTRUMENTS.
a. Explanation. Amendment 29-59 changed the requirements for displaying the normal operating range of powerplant instruments. Most modern glass cockpit designs utilize the “dark, quiet cockpit” concept, which means that yellow or red is presented to indicate abnormal conditions; green ranges are not presented. This approach has required a finding of equivalent safety with § 29.1549(b) for applicants using an unmarked normal operating range instead of green. Section 29.1549(b) continues to allow the green operating range to be displayed as green, but now permits an option for the normal operating range to be unmarked.
b. Procedures. The policy pertaining to these requirements, which is found in section 29.1549 of this AC, remains in effect with the following changes and additions.
For compliance with §§ 29.771(a) and 29.1549(b), electronic displays that lack green arcs must include features that permit the pilot to easily interpret (by way of glancing at the instrument) whether a parameter is in a precautionary range (yellow) or beyond a limit (red). In addition, consistency in displaying all required indications shall be maintained between the primary instrument and the standby instrument to reduce any confusion in the cockpit when failures require using the standby instrument.
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AC 29.1551. § 29.1551 OIL QUANTITY INDICATORS.
a. Background. This section states that each oil quantity indicator must be marked with enough increments to indicate oil quantity readily and accurately.
b. Procedures. There are several differ ent ways in which the oil quantity indicator may be presented. Some of the ones mo re prevalent in the industry are:
(1) Oil quantity indicator. (Generally used when large amounts of reserve oil are required.)
(2) Oil quantity dip stick. (Most common method of measuring engine oil.)
(3) Oil quantity sight indicator. (Gener ally used for measuring transmission and gearbox oil quantities.)
c. No matter what method of oil quantity indicator is used, the indicator should be marked so that the oil quantity can be accurately determined. This can range from increments marked in gallons, such as oil quantity indicators for large amounts of oil, to oil quantity indicators marked in quarts with full and add marks, such as engine dip sticks.
Sight indicators with full and add marks have been used successfully for gearboxes.
Sight indicators normally do not reflect quantities. These are some of the methods currently in use to indicate the oil quantity. In all cases, those methods identified above have proved to be an acceptable method of showing compliance with § 29.1551.
AC 29.1553. § 29.1553 FUEL QUANTITY INDICATOR.
a. Explanation. This section describes the markings necessary to identify the portion of unusable fuel that cannot be used in level flight. Unusable fuel may be present in a design due to the relative configuration of the fuel tank to the fuel tank outlet (e.g., sumps, unusual elevations and/or configurations dictated by aircraft contours, etc.). If the unusable fuel supply fo r any tank is less than or equal to 1 gallon or is less than or equal to 5 percent of the tank capacity, whichever is greater, this section does not apply.
b. Procedures. For each fuel tank wh ich has an unusable fuel capacity exceeding 1 gallon or 5 percent of the tank capacity, whichever is greater, the following should be accomplished:
(1) Calibration computations, measurements, and/or tests should determine the zero (empty) position on the fuel quantity indicator (reference § 29.1337).
(2) The lowest reading obtainable in level flight must be determined by computation, measurement, and/or testing.
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(3) Once the instrument readings defined by paragraphs b(1) and (2) above have been determined, a red arc should be placed between the readings on the fuel quantity indicator.
(4) Appropriate notations should be made in the flight manual to define the intent of the red arc to the flightcrew (reference § 29.1585(e)).
AC 29.1555. § 29.1555 (Amendment 29-24) CONTROL MARKINGS.
a. Explanation. Section 29.1301(b) requires that all installed equipment be labeled to identify its function and operation. This section provides more detailed requirements for control markings. Specific criteria are given for powerplant fuel controls, fuel quantity markings, and landing gear controls. The requirement to color emergency controls red is in this section.
b. Procedures.
(1) Section 29.1555(a) requires that each cockpit control, other than flight controls whose function is not obvious, must be appropriately labeled. The primary flight controls are the cyclic, collective, and the directional control (tail rotor) pedals. For the control to be appropriately labeled, the rule requires that there should be an obvious and clear demarcation of the function and operation of the control. When performing the evaluation to determine the adequacy of markings, it should be remembered that only those controls which are quite traditional should be judged to be obvious in their operation. An example of this has been the navigation/communication control heads.
The more traditional control units had concentric knobs of decreasing size for the selection of frequency. Because this system was so common for such a period of time, the finding was generally made that the function of this control was obvious and thus did not require a specific marking. However, as more current technology digital electronic controls were used, the frequency selectors were judged not to be obvious in their operation, and their function and operation were required to be labeled.
(2) Review design data and available hardware to ensure the powerplant fuel controls are clearly and permanently marked such that:
(i) Selector valve control clearly shows each position for each tank and each crossfeed configuration.
(ii) Tank selection sequences required for safe operation are clearly and permanently marked on or adjacent to the required selector.
(iii) Each control valve is clearly marked to show the position of the controls for each engine on multiengine rotorcraft.
(3) Review design data and available hardware to ensure that usable fuel capacity is clearly marked as follows:
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(i) If the fuel system has no selector controls, usable fuel capacity must be shown on the fuel quantity indicator (reference paragraph AC 29.1553).
(ii) If the system has selector controls, the usable fuel capacity at each selector position must be clearly shown near the selector position.
(4) Markings of essential visual position indicators must be obvious and within view of required crewmembers. Landing gear markings normally include indications for down, intermediate/unsafe, and up. Accepted symbology has included arrows for up/down indications, crosshatching for intermediate/unsafe, various combinations of colored lights, and combinations of all of the above. Cockpit presentation is further discussed in paragraph AC 29.729. Emergency controls which should be marked in red include those used for firewall/emergency fuel shutoff, landing gear blowdown/emergency release, fire extinguishers, float activation, cargo hook release and fuel dump. T he method of operation of emergency controls must be clearly marked. In the case of switches and buttons, the method of operation is often inherently obvious without dedicated labeling.
(5) The two most obvious means of displaying landing gear operating speed are use of a placard or an appropriate mark in the airspeed indicator.
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AC 29.1555A. § 29.1555 (AMENDMENT 29-59) CONTROL MARKINGS.
a. Explanation. Amendment 29-59 changed the requirements for marking the usable fuel capacity for designs that have no selector controls. The previous requirement for marking the usable fuel capacity near the fuel quantity indicator is not practical for modern glass cockpit designs.
With older, electro-mechanical designs, the actual fuel capacity was not marked on the fuel quantity gage. Traditionally these designs used a placard indicating the usable fuel capacity next to the fuel quantity indicator to assist with flight planning and refueling.
Modern glass cockpit designs provide digital indication of the remaining usable fuel quantity at all times while the total usable fuel capacity is typically included, although not required, within the rotorcraft flight manual.
b. Procedures. All of the policy pertaining to this section remains in effect with the following changes:
Section 29.1555(c)(1) requires that, for fuel systems having no selector controls, the usable fuel capacity of the system be indicated at the fuel quantity indicator unless the system capacity is provided by another system or equipment readily accessible to the pilot. Such information may be provided digitally on a multi-function display (MFD) synoptic page such as the fuel system or aircraft weight and balance page. In addition to the digital representation, § 29.1555(c)(1)(ii) requires that the fuel system capacity be contained in the limitations section of the rotorcraft flight manual. The digital display of the fuel system capacity used in conjunction with the total usable fuel quantity provided in the rotorcraft flight manual limitations section will permit the flight crew to approximate endurance and will assist with refueling. Alternately, for designs that do not provide a digital readout of the usable fuel capacity and include the information in the rotorcraft flight manual, the total usable fuel capacity must be displayed at the fuel quantity indicator in accordance with § 29.1555(c)(1).
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AC 29.1557. § 29.1557 (Amendment 29-26) MISCELLANEOUS MARKING S AND PLACARDS.
a. Explanation.
(1) This section specifies the markings and placards associated with baggage, cargo, ballast, seats, fuel, oil, and emergency exits.
(2) The data contained in these markings and placards must conform to the approved type design of the rotorcraft.
b. Procedure.
(1) The placard for baggage and cargo compartment limitations should clearly state all limitations which apply to that compartment. The limitations may apply to what is carried, the dimensions, exact location, and maximum weight allowed. The placard should be located in a place where it cannot be obstructed and is clearly visible before or after opening the compartment. For ballast, the placard should state the type of ballast permitted (lead plate, shot bags, etc.), the exact placement, if applicable, and the maximum allowable weight. If there are other limitations which are applicable to these compartments, they should be clearly stated.
(2) Seats in rotorcraft are designed to meet vertical descent loads which have been established to insure a certain level of occupant survivability in the event of a hard Page G - 30
landing or crash. To meet these load requirements, 170 pounds was established as the minimum occupant design weight. If the seat was designed and certified to an occupant weight lower than 170 pounds, the seat must carry a placard in a conspicuous place, which limits the weight of the seat occupant to the certified weight.
(3) The fuel and oil filler opening markings are self-explanatory.
(4) Emergency exit placards must be so distinctive and clear that they are easily identified and understood under extreme and intense circumstances by individuals who have little or no familiarity with aircraft escape procedures.
AC 29.1559. § 29.1559 (Amendment 29-24) LIMITATIONS PLACARD.
a. Explanation.
(1) The content and location requirements on the placard are specified in the standard. The content and information in the placard has changed significantly as a result of associated and complementary changes in the airworthiness rules and the maintenance and operating rules.
(2) By adoption of FAR Part 29 in 1965, the standard (and its predecessor CAR Part 7) required compliance with the operating limitations in the approved Rotorcraft Flight Manual.
(3) With the adoption of an Airworthiness Limitations Section for the maintenance manual as stated in § 29.1529 of Amendment 29-4, the content of the placard was changed significantly to require compliance with the requirements in that section.
(4) Amendment 29-20, issued in 1980, adopted standards requiring “Instructions for Continued Airworthiness” (maintenance manual). This manual may include an Airworthiness Limitations section which is segregated and an approved part of the manual. The maintenance and operating rules, §§ 43.16, 91.163(c), and other operating rules require compliance with the Airworthiness Limitations Section. Other airworthiness standards were adopted for airplanes, engines, and propellers to similarly require Instructions for Continued Airworthiness and an Airworthiness Limitations Section. See paragraph AC 29.1529 for further information. The limitations placard standard was not changed by this amendment.
(5) Amendment 29-24 adopted a significant change for the placard. The placard must be in clear view of the pilot and must provide a convenient cockpit presentation of the approved types of operation for each aircraft. Other operating and maintenance rules referenced in the previous paragraph provided the basis for much of the change in the placard content.
b. Procedures.
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(1) A placard (or durable decal) must be legible to the pilot and located in clear view of the pilot. If two pilots are required, a single placard may satisfy the standard.
This aspect will be evaluated by a test pilot. The type inspection report (TIR) should contain a compliance check entry.
(2) The placard must specify the kinds of operations such as VFR, IFR, day, night, or icing for which the particular rotorcraft is equipped and approved if Amendment 29-24 applies.
(3) The placard content for older designs is related to the rotorcraft certification basis. If the rotorcraft type design has an “FAA/AUTHORITY -approved” and segregated Airworthiness Limitations Section of the maintenance manual, the limitations placard may be revised to comply with the new standard. The certification basis should be changed in conjunction with the placard change.
AC 29.1561. § 29.1561 SAFETY EQUIPMENT.
a. Explanation. This standard requires an identification or location marking for each item of safety equipment and operating information for crew-operated controls.
Markings and placards must be conspicuous and durable per § 29.1541. Both passengers and crew should be able to identify easily and then use the safety equipment. Liferafts are specifically mentioned.
b. Procedures.
(1) Release devices such as levers or latch handles for life rafts and other safety equipment should be plainly marked. The method of operation should be marked also. Stencils, permanent decals, placards, or other permanent labels or instructions may be used.
(2) Lockers, compartments, or pouches used to contain safety equipment such as life vests, etc., should be marked to identify the equipment therein and to also identify, if not obvious, the method or means of getting to or releasing the equipment.
(3) Safety equipment labels and instructions for use or operation should be used as prescribed. Section 29.1555(d)(2) concerns emergency control markings.
White letters and red background (or reverse) shall be used. Section 29.1541 concerns markings also.
(4) Locating signs for safety equipment should be legible in daylight from the furthest seated point in the cabin or recognizable from a distance equal to the width of the cabin. Letters, 1 inch high, should be acceptable. Operating instructions should be legible from a distance of 30 inches. These are recommendations based on § 29.811(b) and (e)(1).
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(5) As prescribed, each liferaft must have operating instructions.
(6) Easily recognized or identified and easily accessible safety equipment located in view of the occupants may not require locating signs, stencils, or decals.
However, operating instructions are required. A passenger compartment fire extinguisher that is in view of the passengers is an example.
AC 29.1565. § 29.1565 (Amendment 29-3) TAIL ROTOR.
a. Explanation.
(1) This standard concerns tail rotor disc visibility in normal daylight ground conditions. Amendment 29-3 added “daylight” to the standard. A personnel guard is not required. The tail rotor shall be marked to achieve a conspicuous disc whenever the blades are rotating.
(2) Completely shrouded or protected blades may not require contrasting color segments if the shroud provides equivalent protection for personnel on the ground. A simple tubular guard does not alleviate this standard.
b. Procedures .
(1) Each tail rotor blade may be marked with contrasting colors.
(2) During FAA/AUTHORITY compliance inspections or during the flight test program, the tail rotor will be evaluated, qualitatively, in daylight for a conspicuous disc.
(3) As an aid to select proper colors for conspicuousness, see AC 20-47, Exterior Colored Band around Exits on Transport Airplanes. This AC concerns, in part, methods for measuring reflectance (3:1 factor) and contrast colors for transport aircraft.
Section 29.811(f)(2) requires contrast colors for exit markings. The AC also contains suggestions for chromatic contrast. A 3:1 reflectance factor between rotor blade segment colors is acceptable. It is recommended that a few combinations of colors be approved to provide a selection of color combinations. The type design drawings will include the necessary information and data for design control.
(4) As a further aid for compliance AC 91-42D, Hazards of Rotating Propeller and Helicopter Rotor Blades, dated March 3, 1983, should be reviewed. Revision D updates statistical information on propeller and rotor-to-person accidents and offers suggestions to reduce the frequency of such accidents. This AC, in part, refers to FAA Report FAA-AM-78-29, Conspicuity Assessment of Selected Propeller and Tail Rotor Paint Schemes, dated August 1978. The report’s abstract states, in part, for two tail rotor designs, a black and white asymmetrical stripe scheme was chosen as “more conspicuous” than a red, white, and black design.
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SUBPART G - OPERATING LIMITATIONS AND INFORMATION
ROTORCRAFT FLIGHT MANUAL AC 29.1581. § 29.1581 (Amendment 29-15) ROTORCRAFT FLIGHT MANUAL - GENERAL.
a. Explanation.
(1) The primary purpose of the Rotorcraft Flight Manual (RFM) is to provide an authoritative source of information considered to be necessary for or likely to promote safe operation of the rotorcraft.
(2) Since the flightcrew is most directly concerned with operation of the rotorcraft, the language and presentation of the flight manual shall be directed principally to the needs and convenience of the flightcrew, but should not ignore the needs of other contributors to safe operation. As used with respect to the RFM, safe operation is construed to include, but not be limited to, operation of the rotorcraft in the manner that is mandatory for, or recommended for, compliance with applicable airworthiness requirements, and with the particular provisions of the operating regulations relating to the rotorcraft’s approved performance capabilities.
(3) To serve its intended purpose, therefore, the RFM must include the certificate limitations established for the design as a consequence to the type certification evaluation, the performance information necessary to establish the operating limitations imposed in accordance with appropriate operating regulations, and the procedures and other information necessary to enable the flightcrew to safely operate the rotorcraft within the envelope of limitations thus delineated. The outline presented in this circular is directed toward those objectives.
(4) Information and data that are mandatory for an acceptable RFM are prescribed in §§ 29.1581 through 29.1589, and nothing contained in these sections should be construed as amending those requirements. Certain additional elements of flight manuals, however, have been shown by experience to be practical necessities if the document is to serve effectively its intended purpose.
b. Procedures.
(1) The following criteria do not affect the status of RFMs which are presently approved. When such manuals are amended in the future, however, it is recommended that the concepts of this section be incorporated wherever uniformity or clarity will result.
(2) Only the material required by FAR Part 29, or that considered necessary to implement the operating regulation, should be included in the portion of the manual that is approved by the FAA/AUTHORITY. However, the manufacturer or operator may Page G - 34
include other “unapproved” data in a separate and distinctively identified portion within the same document.
The RFM is considered necessary for safe operation of the rotorcraft and care should be taken to produce a manual that is consistent with the need for completeness and clarity of the required information. Also, since the RFM is necessary for operation of the rotorcraft in accordance with the certificate limitations, it is considered to be public information.
(3) The page size for the RFM will be left to the discretion of the manufacturer.
In this regard, operational compliance with § 91.31 should be considered. A cover should be provided and should indicate the nature of the contents by means of the title, “RFM.” Each page of the approved portion should bear the notation “FAA/AUTHORITY approved,” an induction of the approval sequence of that particular page (e.g., a date of approval, a revision number suitably supported by an amendment log which contains the appropriate date, etc.), the rotorcraft model number as it appears on the type data sheet, and any appropriate document identification number. Pages of the unapproved portion of the flight manual would use the issue date in lieu of the FAA/AUTHORITY approved date. The material should be bound in semipermanent fashion so that the pages will be protected and retained in proper sequence. In selecting the form of binding, consideration should be given to the necessity for amendment and the ease with which amendments can be accomplished.
(4) Amendments may take the form of revisions or supplements.
(i) A revision is a change to the RFM or its supplement made by the holder of the applicable type certificate (TC) or in the case of supplement prepared as a part of a supplemental type certificate (STC), by the holder of the STC.
(ii) A supplement is an addition to the RFM. If the rotorcraft manufacturer (holder of the TC) adds optional equipment or specific operations (such as Category ”A” vertical operation or IFR operations), then the rotorcraft manufacturer is responsible for preparing any necessary flight manual material whether he elects it to be a supplement or a revision to the basic manual. If someone other than the rotorcraft manufacturer applies for an STC to install equipment or modify the rotorcraft such that a RFM supplement is necessary, then the person who applies for the STC is responsible for the preparation of the RFM supplement.
(5) “Revision” may be incorporated by inserting new pages which embody the amended text and, where applicable, by removing superseded pages. A vertical amendment bar should be inserted in the outer margin, where practicable, to indicate those parts of the text that have been changed. Each amended page should be identified in the same manner as pages of the basic manual, and in addition should carry an identification of its approval sequence.
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(6) Supplements are incorporated in the manual by inserting the applicable pages which contain the information associated with the particular change. Each supplemental page should also identify the rotorcraft type and model flight manual for which the supplement was issued, the name of the issuer, and the FAA/AUTHORITY approval date. The following statement is an example of a note which would be included on the title page of a flight manual supplement: “For rotorcraft approved to operate in accordance with the provisions of the rotorcraft flight manual supplement, the information contained herein supplements the information of the basic flight manual.
For limitations, procedures, and performance data not contained in this supplement, consult the basic flight manual.”
(7) Supplements should contain as much of the flight manual contents outlined below as considered appropriate for the particular change in type design, including title page and index of contents. It is suggested that these be prepared with a view to insertion in the FAA/AUTHORITY-approved portion of the flight manual as a complete and self-contained unit.
(8) The RFM should contain as much of the information required in Part 29 as is applicable to the individual type and model. For the purpose of standardization, it is recommended that the sequence of sections and of items within sections, follow the format presented at the end of this paragraph if practicable.
(9) The following information would normally be included in the introduction section of the flight manual.
(i) Title Page. This page should include the manufacturer’s name and address and the rotorcraft model number as it appears on the type certificate data sheet. If desired, include a trade name or trade model number in quotes, provisions for rotorcraft serial number and registration number, approval date of the basic document, and title and signature of the FAA/AUTHORITY approving official.
(ii) Table of Contents. An index should be located at the front of each section or at the front part of the manual.
(iii) Amendment Log. This log should be in the form of a table with provisions to record, for each amendment, an identifying number, title or description, the page numbers involved, the issue date, the identification of the FAA/AUTHORITY approving official, and the FAA/AUTHORITY approval date.
(iv) Separate amendment logs should be provided for each type of amendment issued; i.e., Log of Revisions, Log of Supplements, etc. Amendments issued by other than the holder of the basic type certificate should include a separate amendment log which, in addition to the issue date, should also identify the issuer and the STC number or other approval basis for the associated modification.
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