AC 135-14B

Advisory circular · Helicopter Air Ambulance Operations

Approved
March 26, 2015
Last reviewed
September 3, 2024
Cancels
AC135-14A
Family
AC 135-14 · 2 versions
Revision
B
14 CFR parts
135, 1, 27, 29, 43, 61, 65, 91, 119, 120, 157
Cited by
1 AD
14 CFR sections
§ 135.617

Guidance, not mandatory unless a rule or AD requires it. DRS record last changed November 21, 2025.

Show pages 4–15

Par 2-4 Page 12 12-month period before a pilot can use the lower weather minimums associated with the LFA.

This examination of familiarity with a LFA may be through other means than a flight check.

However, a record of all such examinations, regardless of format, must be retained for each pilot and each LFA assigned (refer to § 135.609). In this AC, see paragraph 3-5 for LFA operational considerations, paragraph 4-2 for LFA training implementation details, and paragraph 7-2 for LFA examination documentation requirements.

c. Sections 135.611 and 135.613, Instrument Flight Rules (IFR) Procedure Documentation. It is recommended that part 135 certificate holders conducting HAA IFR operations document procedures associated with point in space (PinS) approaches and associated Obstacle Departure Procedure (ODP). (Refer to §§ 135.611 and 135.613.)

d. Section 135.615, Visual Flight Rules (VFR) Flight Planning Documentation.

Procedures for VFR flight planning must be documented by part 135 certificate holders conducting HAA operations in accordance with the provisions of § 135.615.

e. Section 135.617, Preflight Risk Analysis. An FAA-approved preflight risk analysis program must be established by each HAA operator and documented in its operational manual (or other documentation). In accordance with the provisions of § 135.617(d), part 135 certificate holders conducting HAA operations are required to use and retain preflight risk analysis worksheets. Preflight risk analysis worksheets are completed by the pilot and are reviewed and confirmed by the Operations Control Specialists (OCS) in compliance with § 135.617 if applicable. These worksheets are retained for 90 days in compliance with §§ 135.617 and 135.619. The procedure itself is outlined in paragraph 3-4 and Appendix A, which also includes examples of preflight risk analysis worksheets.

2-5. TRAINING CONSIDERATIONS. HAA operators are subject to additional training requirements above those associated with other part 135 operations. These training requirements will be outlined in Chapter 4. In addition, this AC will identify HAA industry best practices applicable to training, including providing examples of curriculum outlines and checklists as appendices.

2-6. EQUIPMENT CONSIDERATIONS. Part 135 certificate holders conducting HAA operations will utilize task-specific equipment associated with medical transport. An applicant should identify, in their initial application, any specialized equipment that may be used in their HAA operations. This equipment should include items required by regulations such as a Helicopter Terrain Awareness and Warning System (HTAWS) and a radio altimeter. By April 23, 2018, helicopters must equip Flight Data Monitoring Systems (FDMS). It may include a Night Vision Imaging System (NVIS) installation and other equipment fitted to bring each helicopter to a desired aeromedical configuration. Helicopters to be used in HAA operations are evaluated by FAA PIs.

2-7. INSPECTION AND MAINTENANCE CONSIDERATIONS. HAA operators should consider inspection and maintenance issues beyond those associated with other part 135 operations. This includes inspecting and maintaining equipment added for HAA operations. This equipment increases maintenance complexity and introduces second-order complications. These complications may include NVIS compatibility, electromagnetic compatibility (EMC)

Par 2-7 Page 13 (and 14) verification, heat shielding, fire resistance, mechanical integrity of mounting, crashworthiness and infection control procedures. Maintenance hours and cost burdens will increase because of the need to remove and replace complex on-board systems, sealed interior panels, etc., when required to access aircraft systems for inspection, maintenance and repair. The operator should factor these considerations into both routine and unscheduled maintenance decisionmaking. For example, it is not acceptable to apply for multiple extensions on deferrals of required maintenance for minimum equipment list (MEL) items solely due to the cost burden associated with gaining access to make repairs. Be on guard against such practices. Standard MEL deferral decisionmaking should be consistently applied.

NOTE: Reference materials providing further guidance include: AC 27-1B MG 6, Miscellaneous Guidance (MG) for Emergency Medical Service (EMS) Systems Installations.

2-8. DOCUMENTATION AND RECORDKEEPING CONSIDERATIONS. All HAA operators are required to document preflight risk analysis and VFR flight planning procedures. In addition to the manual requirements imposed by § 135.21, it is recommended that each certificate holder conducting HAA operations, including single-pilot and basic operators, compile and maintain manuals reflecting the implementation of HAA best practices identified in this AC. Documentation and recordkeeping requirements associated with HAA operations beyond those normally required of part 135 operators are described in Chapter 7 of this AC.

Par 3-1 Page 15 CHAPTER 3. OPERATIONS

3-1. GENERAL. This chapter outlines recommendations regarding the conduct of Title 14 of the Code of Federal Regulations (14 CFR) part 135 helicopter air ambulance (HAA) operations.

3-2. OPERATIONAL CONTROL, FLIGHT LOCATING, AND FLIGHT FOLLOWING DUTIES AND RESPONSIBILITIES. Regardless of the size and complexity of the operation, the operator is responsible for maintaining operational control, accomplishing flight locating and supporting the pilot during preflight planning, risk analysis, and en route by providing information and constructive input which would aid the pilot in effective decisionmaking.

Smaller operations may accomplish this through direct communication between the pilot and the management person to whom the authority to provide a flight authorization has been delegated.

Larger operations may accomplish the same objective through pilot communication and discussion with a trained Operations Control Specialist (OCS).

a. Operational Control. Only those individuals authorized by name in an operator’s operations specification (OpSpec) may exercise operational control. While operational control may be delegated to certain certificate holder personnel, it must never be delegated to customer hospitals or external emergency medical services (EMS) agencies.

b. Duties and Responsibilities. The pilot in command (PIC), by regulation, is the final authority for the operation of any HAA flight. It is an HAA industry best practice that a PIC may not “self-launch.” Operators should establish procedures for coordination between the pilot and OCS, or other person authorized to exercise operational control, to evaluate flight risk analyses to ensure risk is mitigated to the extent possible or a flight request is declined due to unacceptable risk. While “three to go, one to say no” is a good practice (with the three being the PIC and two medical crew members, and the one being any one of the three), it is essential that no external pressure “to go” is applied to the pilot during the decisionmaking process.

NOTE: A PIC’s decision to decline, cancel, divert or terminate a flight overrides any decision by any and all other parties to accept or continue a flight.

c. Flight Authorization and Flight Locating Procedures. Regardless of whether or not an operator uses an Operations Control Center (OCC), flight authorization and flight locating procedures should be well-considered and thoroughly documented to support training and operations. For those operators with an OCC, the description of the duties and responsibilities of OCSs and an explanation of their duty times in the current edition of Advisory Circular (AC) 120-96, Integration of Operations Control Centers into Helicopter Emergency Medical Services Operations, should amplify the above. In addition, the rule describing OCS training part 135, § 135.619(f) is an excellent guide to the subject matter considerations involved in issuing a flight authorization and with reacting to flight locating adverse outcomes. The certificate holder is required by regulation to use flight locating procedures (refer to § 135.79), unless a Federal Aviation Administration (FAA) flight plan is filed and activated.

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d. Flight Following.

(1) Flight Following Recommendations. Flight following is distinguished from flight locating. Flight locating is required for HAA operations unless an FAA flight plan is filed and activated. While § 135.619 requires an OCC to monitor the progress of a flight, for smaller operators (ten or less HAAs), it is a good practice to employ flight following.

(2) Flight Following Connectivity. Flight following should maintain voice communications with helicopter pilots during HAA operations. The operator may wish to consider employing satellite/Global Positioning System (GPS) tracking for flight following tasks as a supplement or substitute for voice radio connectivity.

(3) Flight Following Latency. It is recommended that a position and status report be made, at most, every 15 (in flight) to 45 (on ground) minutes. If communication is lost, the aircraft may be considered missing after failing to provide sequential routine position reports (usually two reports). The longer the time between position reports, the greater the radius of uncertainty of the missing helicopter’s location. The operator should also consider employing satellite/GPS tracking for flight following tasks as a substitute for voice radio connectivity.

e. Flight Following and Accident Incident Plan/Post-Accident Incident Plan (AIP/PAIP). Each OCC or other flight following office should have access to the operator’s AIP/PAIP. The plan should be reviewed and updated annually or more frequently as needed.

(1) Information in the AIP/PAIP defines and provides direction for emergency response procedures that should be used as a basis for training or for reference in the event of a mishap, accident or other emergency. The AIP/PAIP establishes standard emergency response procedures that OCSs or flight followers will carry out in all cases when an aircraft meets operator-defined criteria of being overdue or has been involved in an incident or accident.

(2) The AIP/PAIP and any other emergency response plans and guides may be formatted in a variety of ways, provided the user (that is, the individual making the initial response to the emergency) can easily determine where to find guidance for a situation and then follow a generic checklist of actions to be taken for that situation. An addendum to the main response plan should be available for every satellite base. Each local addendum should list direct-dial phone numbers for the satellite base manager, local first responder and 911 dispatch organizations, local air traffic control (ATC) and local FAA offices.

f. Communications Personnel and Procedures. Chapter 6 of this AC provides recommendations to assist HAA operators with best practices for implementing OCCs and operational control procedures.

(1) Large HAA operators have developed OCCs to maintain operational control. While there is a regulatory requirement (§ 135.619) for operators with 10 or more HAAs to have OCCs, smaller operators should consider the benefits that best practices have shown can be implemented on a scalable level to meet the needs of smaller operators.

(2) Operators without an OCC, and large operators may find it advantageous to supplement their Operational Control personnel through the addition of Communications

Par 3-2 Page 17 Specialist Staff. If this is the case, the Operator must train and qualify their Communications Specialists to the extent their duties and responsibilities reflect delegated Operational Control tasks. For example, if a Communication Specialist is responsible for performing flight locating duties via radio or other communications process, and to receive and offer the operator flight requests for HAA operations their training should include company policy and procedures for such activity.

(3) A communications specialist may be an employee of the HAA operator, a hospital

(i.e., a hospital communications specialist) or a local public safety agency (i.e., a 911 dispatch operator. If communications specialist duties are delegated beyond certificate-holder personnel, such as to a hospital or ambulance dispatch center, those individuals serving in that capacity must be trained by the certificate holder and such training programs must be documented.

(4) The primary function of the communications specialist is to support HAA operations by relaying coordination information and situational awareness information among the flightcrew, hospital, and on-scene personnel and other involved organizations and individuals. Providing and receiving in-flight updates and post-flight debriefs to flightcrews have been identified as part of their recommended functions.

(5) HAA best practices suggest that the responsibilities of communications specialists should include ascertaining, from those requesting HAA services, whether another HAA operator has previously declined to carry out a particular flight and, if so, for what reason. The response received should be conveyed to the pilot performing the Risk Analysis in accordance with § 135.617. The personnel that carry out this function may or may not be the same as those who carry out in-flight connectivity and flight locating functions during HAA operations.

(6) Depending on the size and nature of HAA operations, different communications specialist functions may be split between multiple individuals (who may also carry out other functions) or concentrated in one or more communications specialists.

(7) Communications specialist duties may include flight following. Best practices suggest that an HAA operator’s communications system should provide reliable connectivity with HAAs in flight and on the ground, enable flight locating (required by regulation for some operators and recommended for all others) and ensure that medical personnel and pilot(s) can communicate with recipients such as hospitals and ground personnel at a Landing Zone (LZ).

Some rural hospitals may not have communications capability other than by phone.

Communications specialist personnel may be required to act as an intermediary.

(8) In all cases, when communications specialists perform an OCS duty included in § 135.619(a)(1-4), the communication specialist is subject to training and checking in those subjects that support the duty performed and must be trained in the limit of authority delegated to them.

3-3. VISUAL FLIGHT RULES (VFR)/INSTRUMENT FLIGHT RULES (IFR) FLIGHT PLANNING AND WEATHER MINIMUMS.

a. Flight Planning (refer to §§ 135.613 and 135.615).

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(1) HAA VFR flight planning must take into consideration factors including the determination of highest obstacles and minimum cruising altitudes along planned routes as well as contingencies such as deviations due to medical necessity, dynamic weather and changes to the planned flight. The procedures defining these planning methods must be documented. (Refer to § 135.615 for regulatory requirements.)

(2) IFR/VFR Procedures. For operators with IFR authorization, procedures for transitioning from IFR to VFR on approach or from VFR to IFR on departure are required to be documented.

b. Approach Procedures Minimums (refer to §§ 135.609, 135.611 and 135.613).

(1) When executing Point in Space (PinS) Copter approaches that include a “proceed visually” transition, the flight will remain under IFR from the missed approach point (MAP) to a served heliport and the transition must be conducted in accordance with the ceiling and visibility limitations published in the PinS Copter Instrument Approach Procedure (IAP).

(2) When executing PinS Copter approaches that include a “proceed VFR” segment between the MAP and a served heliport, flights must be conducted in accordance with the ceiling and visibility limitations published in § 135.613(a).

(3) When accessing a heliport near an airport served by an IAP, the pilot may execute a published IAP to an airport which is not the intended landing site, and then break off that published approach after visually acquiring the airport served by the approach and then proceed to a landing area other than the airport to which the approach was conducted. The pilot may accomplish this only under VFR weather minimums in accordance with § 135.613(a) or under VFR as appropriate to the class of airspace involved and in accordance with ATC clearances.

(The airspace between the protected area surrounding the approach to the airport and the intended landing area located nearby may not be surveyed and obstructions may exist between the airspace protected for the airport served by the IAP and the intended landing site.)

c. Departure Procedures Minimums (refer to §§ 135.609 and 135.613).

(1) HAA Helicopters may depart on an IFR clearance from the surface, at heliports that are not served by weather reporting, providing the heliport is served by a departure procedure (Standard Instrument Departure (SID) or Obstacle Departure Procedure (ODP)) containing ODP and takeoff minimums, and the pilot determines the weather at the departure point meets or exceeds the published takeoff minimums. The flight may depart and proceed visually in accordance with the instructions contained in the DP.

(2) When departing VFR from heliports with the intent of acquiring an IFR clearance at or before reaching a predetermined point (usually the Initial Departure Fix (IDF) not more than 3 nautical miles (NM) from the departure point, the flight must be conducted in accordance with the DP instructions and the ceiling and visibility limitations contained in § 135.613)(a). If the distance between the departure point and the IDF exceeds 3 NM, the flight must be conducted in accordance with the VFR ceiling and visibility minimums for the class of airspace involved. The operator should document procedures for transitioning from IFR to VFR on approach or from VFR to IFR on departure.

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(3) If the departure involves a VFR to IFR transition and does not meet the requirements of § 135.613(b)(1), there is no departure procedure, and/or the IDF is more than 3 NM from the point of liftoff, the VFR weather minimums required by the class of airspace apply. If the flight is within Class G, airspace, refer to § 135.609, if within Class B, C, D, or E airspace, refer to § 135.205.

(4) These regulations do not restrict or prohibit “diverse departures" from airports from which IFR departures can be made in accordance with 14 CFR part 97. These are departures from airports with IAPs that have had an obstacle analysis conducted and from which it was determined IFR departures can be performed safely without a published ODP or SID.

(5) An IFR clearance and departure with “proceed visually” text is not considered a VFR maneuver and is not subject to § 135.609 limitations unless the pilot is instructed by ATC to maintain VFR. For this type departure, the weather must meet or exceed either the published “takeoff minimums” contained in the DP, or the restrictions in contained in § 135.613 or in § 135.609, as applicable.

d. Flight Into Locations Without Weather Reporting (refer to § 135.611(a)(3)). In accordance with the provisions of § 135.611(a)(3), the PIC may assess the weather at a departure point where weather reporting is not provided. This is a process where the PIC applies his own professional judgment to determine the weather conditions. The pilot may be assisted by access to enhanced situational awareness provided by the OCC or other aviation or non-aviation weather sources. (See Chapter 6 of this AC and AC 120-96 for more information.)

(1) Based on this weather assessment, the PIC may:

• Takeoff when the observed ceiling and visibility is greater than the weather minimums as published in a departure procedure; or

• Takeoff when a documented departure procedure is not available and when the observed weather is greater than the higher minimum ceiling and visibility limitations required by § 135.609, or for the Class B, D, or E airspace overlying the departure point, as applicable.

(2) The FAA intends to permit HAA flights to enter the National Airspace System (NAS) under IFR when visibilities and ceilings are below VFR minimums, based on the pilot’s weather observations, thus increasing the safety of the flight. This rule permits HAAs to depart heliports with a published IAP and departure procedure with no reported weather under IFR, rather than forcing them to depart under VFR, which in low ceiling and visibility conditions is more hazardous.

e. Weather Minimums (refer to § 135.609). Section 135.609 specifies HAA minimums for Class G airspace. HAA operations use higher ceiling and visibility minimums in uncontrolled airspace in uncontrolled airspace than is required for conventional part 135 operations. Each HAA base may establish one or more local flying areas (LFA) where lower minimums may be used. See paragraph 3-5 of this AC on LFAs.

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3-4. PREFLIGHT RISK ANALYSIS (refer to § 135.617). Preflight risk analysis is a key subject of this AC. It is discussed in chapters 3, 6, and Appendix A. This AC provides guidance for implementation of regulatory requirements. Each HAA operator, regardless of size, must design, develop, document and implement an FAA-approved preflight risk analysis process.

Only processes that have been documented and have been the subject of training, meet regulatory requirements. (Refer to § 135.617.)

a. Risk Analysis Steps. Risk analysis includes the following steps:

(1) Risk identification. What are the risks and their importance in quantitative terms?

(2) Mitigation. What changes or approaches reduce the effect of risks?

(3) Calculation of Residual Risks. What risk remains after mitigation?

(4) Management Review. Elevation of higher risk assessment to appropriate management levels for concurrence.

b. Risk Analysis. Risk assessment is a key element of risk analysis. Its process documentation should identify risk factors the HAA operator may consider. This assessment should consider not only the primary intended flight operation but also all contingencies that can reasonably be foreseen. The PIC does not have to perform a new risk assessment prior to a change in destinations. As part of risk assessment, these factors are quantified. The operator should assign to each risk factor an appropriate value reflecting both the likelihood of occurrence and severity of outcome. Combining the value associated with each risk factor will yield a total risk value. An example of this is provided in Appendix A.

c. Flight Authorization. Each HAA operator must document procedures for obtaining and documenting approval by management personnel to authorize a flight when a single or cumulative risk exceeds a level predetermined by the operator. If this value exceeds that predetermined level, it will require management approval or preclude operations. After all risks are identified and risk control strategies and their effects are considered, an informed go/no-go decision can be made. The effect of risk assessment on mitigation strategies and restrictions on acceptable risks must be documented.

d. Risk Assessment Quantifies at Least the Following Risk Factors.

(1) Aircraft Capabilities, Flight Route and Landing Site Considerations. This includes performance, fuel required, resulting useful load, environmental factors and their effect on performance with all engines operating and, as applicable, with one engine inoperative as well as obstacles and terrain along the planned route of flight and LZ conditions. In-flight changes to routes or destinations do not necessarily require a full risk analysis, provided these options or contingencies were considered in the original risk analysis of the flight operation that was conducted prior to the flight operation was initiated. The original risk analysis should be updated, considering factors which have changed, such as: fuel required, fatigue, airworthiness, and dynamic weather conditions, etc.

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(2) Current and Forecast Weather. This includes ceiling, visibility, precipitation, surface winds, winds aloft, potential for ground fog (especially for off-airport scene response operations), and severe weather such as thunderstorms and icing. These factors should be considered for the departure point, en route, and primary destination and contingency routes/diversion landing facilities.

(3) Human Factors. This includes sources of stress such as health, fatigue, circadian effects, flight difficulty, operational complexity and potentially distracting life events. All these are among the many potential contributors to human failure. Human factors considerations should include information such as pilot experience level and operation-specific hazards that also reflect environmental factors.

(4) Declined HAA Flight Requests. The operator must establish a procedure for determining whether another HAA operator has declined the flight request under consideration and if so, for what reason (weather, maintenance, etc.). If applicable, the reason for the declined flight must be factored into the required risk assessment process, i.e., do not include a declined flight due to a maintenance issue or pilot not available. This could be as simple as asking the requestor whether or not this specific flight request has previously been made and declined and why.

(5) Risk Determined Independent of Patient Condition. It should be assumed that HAA operators and personnel are dedicated to making every flight requested, providing the level of risk is acceptable. Best practices in the industry indicate the medical condition of a patient should not be considered in the risk analysis process and that the PIC should not be briefed on this factor in advance of decisionmaking.

e. Mitigation. Identified risks may be mitigated by changing how a proposed HAA flight is conducted. The operator must develop strategies and procedures for controlling risks imposed by identified hazards. For examples of mitigation, refer to Appendix A.

f. Calculation of Residual Risk. After risk is analyzed and quantified and then mitigated, the degree of residual risk is assessed. Residual risk is the safety risk that exists after all controls have been implemented or exhausted and verified.

g. Elevation of Higher Risk Analysis to Appropriate Management. An HAA operator is required to define risk-based flight authorization limits based upon a quantitative assessment of each specific flight operation. Higher risk assessments are referred to an appropriate manager with operations control authority.

h. Reconsideration of Flight Authorization. Material changes in any of the major risk factors considered in the decisionmaking process should trigger reconsideration of flight authorization. This especially applies to deterioration in weather or other environmental conditions or deterioration of patient condition resulting in an unplanned diversion.

3-5. LFAs (refer to § 135.609).

a. Establishing LFAs.

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(1) Each HAA base may establish one or more LFA. A LFA is considered a defined or bounded area within which a HAA pilot has demonstrated detailed local knowledge and within which lower Class G weather minimums may be applicable.

(2) A LFA may be symmetrical, such as an area encompassed by a fixed radius from a point designated by the operator or, alternatively, it may be asymmetrical, using landmarks and geographical features to bound the area. In any case, a designated LFA should not exceed 50 NM in any direction from the designated location.

(3) LFA(s) need not be contiguous. There is no requirement that a LFA for a particular base of operations consist of only one defined area. For example, if an operator that conducts HAA operations in a particular metropolitan area, but often transports patients to a regional trauma center outside that area, may choose to develop an additional LFA for assigned pilots to use when operating near the trauma center. While operating in-between LFAs, cross-country minimums would apply.

FIGURE 3-1. EXAMPLE OF LOCAL FLYING AREA(S) AND WHERE

CROSS-COUNTRY MINIMUMS APPLY

b. References. References to define a LFA may include:

(1) A specific radius from a point (if easily identified using installed operational avionics).

(2) Bounding natural and constructed references (rivers, shorelines, roads, railroads, etc.).

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(3) Governmental boundaries, if easily identified from the air.

(4) By describing an area bounded by natural, constructed or aeronautical reference points (shoreline points, islands, valleys, buildings, airports, very high frequency (VHF) omnidirectional range station (VOR), GPS waypoints, etc.).

(5) Any other reasonable description of an area that may be easily applied by a flightcrew, such as a predetermined route or system of routes.

c. Effects of LFA on Minimum Acceptable Weather Conditions. Establishment of a LFA allows for the use of lower weather minimums as specified in § 135.609. This is only available for use by pilots that have demonstrated LFA familiarity.

d. Demonstration of LFA Familiarity. A pilot must demonstrate a level of familiarity with a LFA by passing an examination given by the certificate holder within the preceding 12 calendar-months prior to using a LFA’s local area weather minimums as specified in § 135.609. This examination may be oral or written and may be part of a line check consisted under § 135.299. The manner of the examination must be described in the operator’s training program. The grace provisions of § 135.301 apply. This examination should include at least the following:

(1) Terrain features and LFA boundaries.

(2) Prominent obstructions including areas of obstruction.

(3) Minimum safe altitudes in the area.

(4) Weather producers (such as industrial areas, fog-prone areas, etc.).

(5) Areas of poor surface lighting and the effects of seasonal and other changes on surface lighting, as applicable to the area.

(6) Airspace control/air traffic facilities.

(7) Radar and communications coverage, including minimum altitudes for radar service and communications with air traffic facilities and company communications facilities.

(8) Airports/heliports/fuel sources, including night availability; available instrument approaches.

(9) Predominant air traffic flows.

(10) Landmarks and constructed features.

(11) Facility-specific information such as flight locating, dispatch and communications.

(12) Any emergency considerations specific to the area.