faa requirements for engine-out procedures and...

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FAA Requirements for Engine-out Procedures and Obstacle Clearance29 Nov. 2005

FAA Requirements forEngine-out Procedures and Obstacle Clearance

Presentation to: CAAC Engine-out Procedures Seminar

Name: Chuck Friesenhahn

Flight Standards Senior Advisor, Advanced Technology

Date: 11/29/2005

Applicable Directives

• Part 25.111 Takeoff path• Part 25.113 Takeoff distance / takeoff run• Part 25.115 Takeoff flight path• Part 25.121 Climb:one-engine inoperative

• Part 121.189 Airplanes: Turbine engine powered: Takeoff limitations

• Advisory Circular AC-120 OBS



Part 25.111 Takeoff path

• The takeoff path extends from a standing start to a point in the takeoff at which the airplane is 1,500 feet above the takeoff surface, or at which the transition from the takeoff to the en route configuration is completed and VFTO is reached, whichever point is higher



Part 25.113 Takeoff distance/takeoff run

• Generally, takeoff distance is the horizontal distance along the takeoff path from the start of the takeoff to the point at which the airplane is 35 feet above the takeoff surface

• Generally, takeoff run is the horizontal distance along the takeoff path from the start of the takeoff to a point equidistant between the point at which VLOF is reached and the point at which the airplane is 35 feet above the takeoff surface



Part 25.115 Takeoff flight path

• The takeoff flight path shall be considered to begin 35 feet above the takeoff surface at the end of the takeoff distance….

• The net takeoff flight path data must be determined so that they represent the actual takeoff flight paths…..reduced at each point by a gradient of climb equal to 0.8 for two-engine airplanes



Part 25.121 Climb: One-engine- inoperative

For two-engine airplanes--------• With landing gear extended,… the steady

gradient of climb must be positive • With landing gear retracted,… the steady

gradient of climb may not be less than 2.4 percent

• At the end of the takeoff path,… the steady gradient of climb may not be less than 1.2 percent



Part 121.189 Airplanes: Turbine engine powered: Takeoff limitations

• May not takeoff at a weight greater than that listed in the Airplane Flight Manual

• Accelerate-stop distance must not exceed the length of runway plus any stopway

• Takeoff distance must not exceed the length of runway plus any clearway

• The takeoff run must not be greater than the length of the runway



Part 121.189 continued

• Takeoff flight path must clear obstacles by at least 35 feet vertically, or by at least 200 feet horizontally within the airport boundaries and by at least 300 feet after passing the airport boundaries

• It is assumed that the airplane is not banked before reaching a height of 50 feet, and maximum bank is not more than 15 degrees thereafter



Basic Requirement

• Aircraft certificated under Part 25 and operated under Part 121 of the Federal Aviation Regulations must be able to takeoff and climb at 2.4% - 0.8% or 1.6% (62.5:1) gradient with one engine inoperative (OEI)

• Maximum takeoff weight (MTOW) is sometimes reduced (fewer passengers, less cargo, or fuel) to climb in compliance with Parts 25 and 121 and safely avoid obstacles if an engine fails



Draft Advisory Circular AC-120 OBSAirport Obstacle Analysis

• Currently FAA deals with obstacles affecting Part 25 and 121 OEI requirements through approval of air carrier departure procedures

• Procedures vary by airline and aircraft, depending each particular type and configuration

• Many carriers follow guidance in Draft AC-120 OBS Airport Obstacle Analysis



Draft AC-120 OBS continuedPURPOSE. This Advisory Circular (AC) describes acceptable methods andguidelines for developing takeoff and initial climb-out airport obstacle analysesand in-flight procedures to comply with the intent of the regulatory requirementsof Title 14 of the Code of Federal Regulations (14 CFR) sections 121.177,121.189, 135.367, 135.379, and 135.398 and other associated one-engine-inoperative requirements relating to turbine engine powered airplanes operated under parts 121 and 135. The methods and guidelines presented in this AC are neither mandatory nor the only acceptable methods for ensuring compliance with the regulatory sections. Operators may use other methods if those methods areshown to provide the necessary level of safety and are acceptable to the Federal Aviation Administration (FAA). This AC need not serve as the sole basis for determining whether an obstacle analysis program meets the intent of the regulations. However, the methods and guidelines described in this AC have been derived from extensive FAA and industry experience and are considered acceptable to the FAA when appropriately used.



Draft AC-120 OBS continued

• Sets forth an area of obstacle accountability for a safe OEI departure path

• Departure procedures provide aircraft trajectories to safely avoid obstacles

• Includes provisions for minor turns to safely avoid obstacles

• Primary Operations Inspectors (POI) review departure procedures and approve as part of a carrier’s operations specifications



Straight-Out Departures



Turning Departures



Managing Proposed Obstructions• The FAA conducts aeronautical studies and

determines possible adverse impact upon the safe and efficient use of navigable airspace by proposed structures, considering: · Impact on departure procedures for aircraft

operating under VFR, and IFR · Impact on existing and planned airports· Cumulative impact from proposed structure

and other existing or proposed structures• FAA issues a determination of presumed

hazard, no hazard, or hazard



Obstacle Evaluation Process



The FAA is authorized to require notice of Proposed construction, and conduct Aeronautical Studies. The FAA cannot approve or deny construction based on the outcome of the study. What constitutes a hazard to air navigation? · Exceeds obstruction standards, Part 77,

Objects Affecting Navigable Airspace · Has an adverse impact as outlined in FAA

Order 7400.2, causes electromagnetic interference, or significant amount of flight operations affected

FAA ORDER 7400.2E Chapter 66-3-3. DETERMINING ADVERSE EFFECT• A structure is considered to have an adverse aeronautical effect if it first exceeds the obstruction standards of

part 77, and/or is found to have physical or electromagnetic radiation effect on the operation of air navigation facilities. A proposed or existing structure, if not amended, altered, or removed, has an adverse effect if it would:

a) Require a change to an existing or planned IFR minimum flight altitude, a published or special instrument procedure, or an IFR departure procedure for a public-use airport.

b) Require a VFR operation, to change its regular flight course or altitude. This does not apply to VFR military training route (VR) operations conducted under part 137, or operations conducted under a waiver or exemption to the CFR.

c) Restrict the clear view of runways, helipads, taxiways, or traffic patterns from the airport traffic control tower cab.

d) Derogate airport capacity/efficiency. e) Affect future VFR and/or IFR operations as indicated by plans on file. f) Affect the usable length of an existing or planned runway.

6-3-4. DETERMINING SIGNIFICANT VOLUME OF ACTIVITY• The type of activity must be considered in reaching a decision on the question of what volume of aeronautical

activity is "significant." For example, if one or more aeronautical operations per day would be affected, this would indicate regular and continuing activity, thus a significant volume no matter what the type of operation. However, an affected instrument procedure or minimum altitude may need to be used only an average of once a week to be considered significant if the procedure is one which serves as the primary procedure under certain conditions.

6-3-5. SUBSTANTIAL ADVERSE EFFECT• A proposed structure would have, or an existing structure has, a substantial adverse effect if it causes

electromagnetic interference to the operation of an air navigation facility or the signal used by aircraft, or if there is a combination of:

a) Adverse effect as described in paragraph 6-3-3; and b) A significant volume of aeronautical operations, as described in paragraph 6-3-4, would be affected.



Proposed Obstacle Identification Surface



QUESTIONS?



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