8900.1 CHG 662



Section 1  Operational Emphasis Items

3-261    GENERAL. This section includes information that is not task-specific, but is of importance to inspectors performing inspections and other contacts with airmen and operators.

3-262    HAZARDS ASSOCIATED WITH IMPROPER SECURITY OF NOSE SECTION EXTERIOR CARGO DOORS. Investigation of a fatal accident revealed that the nose baggage door of a twin-engine aircraft opened in flight shortly after takeoff. Eight people died in the ensuing accident. Further investigation revealed a bypass of the safety interlock feature on the nose baggage door sometime before the accident. Therefore, the pilot received no warning that the door was unlocked.

A.    Continued Occurrences. The continued occurrence of unwanted nose baggage door openings on small twin-engine aircraft indicates a safety problem still exists with small aircraft that use the nose section as a baggage area.

1)    The nose baggage doors of these aircraft may have door warning lights located in the cockpit. The warning lights illuminate to indicate an open or unsecured baggage door.
2)    Some models have a safety interlock feature designed to prevent an engine start if the nose baggage compartment door is not properly latched.
3)    The warning light system and the safety interlock may become inoperative or one may intentionally bypass the system. When the pilot is not aware of an open or improperly latched nose baggage door, door opening and release of cargo can occur with catastrophic results.

B.    Federal Aviation Administration (FAA) Responsibilities. In all contacts with operators of twin‑engine aircraft with nose section cargo storage areas, inspectors should inform operators and pilots of the hazards associated with improper security of nose section exterior cargo doors.

1)    Inspectors should suggest that the operators establish and use a procedure to ensure the security of all exterior cargo doors before flight. The inspector should also recommend installation of secondary locking devices or cargo restraint systems.
2)    During inspection of this type of aircraft, an Airworthiness inspector should determine if an installed safety interlock feature is functioning properly or if it has been bypassed. Properly repair malfunctioning warning or safety interlock systems before flight.

3-263    AIR TRAFFIC CONTROL (ATC) CLEARANCE READBACK. Over the past several years, accidents and incidents have occurred because of misunderstandings between pilots and controllers. As a result of National Transportation Safety Board (NTSB) investigations and recommendations, the ATC Handbook has been amended to require a readback of any altitude assignment or a vectoring heading assignment.

A.    Adherence to Communications Procedures. In all contacts with pilots, instructors, examiners, and pilot schools, inspectors should emphasize the need for strict adherence to communications procedural requirements.

B.    ATC Readbacks. During contact with pilots, inspectors should stress the possible hazards associated with pilot and controller misunderstandings. Clear readback of ATC altitude or heading clearances helps to avoid such misunderstandings.

3-264    PASSENGER EMERGENCY BRIEFINGS. After the crash of a corporate jet, the passengers had difficulty evacuating the airplane because of insufficient knowledge of emergency procedures. No one briefed the passengers as required by Title 14 of the Code of Federal Regulations (14 CFR) part 91, § 91.519. Furthermore, no one posted the placarded instructions for opening the main cabin door or the overhead emergency exits as required by 14 CFR part 25, § 25.811. In addition, a small carpet became wedged underneath the door separating the passenger cabin from the main entrance area, adding to the problems in evacuating the aircraft.

A.    Responsibilities of Corporate Operators. Operators of corporate aircraft should:

1)    Ensure that passengers are made aware of emergency procedures before takeoff.
2)    Ensure compliance with placard requirements.
3)    Ensure that procedures to stow all loose items in the aircraft before takeoff and landing are in effect.
4)    Periodically review the accuracy and appropriateness of the passenger briefing cards.

B.    FAA Responsibilities. During surveillance or other contact with corporate aircraft operators, inspectors must stress the importance of briefing passengers on emergency procedures before flight.

3-265    USE OF MANUFACTURER CHECKLISTS. Investigation of an accident involving a jet aircraft operated under part 91 subpart D revealed that the flightcrew members failed to check the emergency/park brake handle position before takeoff.

A.    Takeoff Crash. In this accident, an aircraft crashed when the pilot was unable to rotate the aircraft to the proper pitch attitude during an attempted takeoff. Examination of the emergency/park brake lever indicated that the lever was in the “park” position during the takeoff roll.

B.    Manufacturer Checklists. Comparison of the manufacturer’s suggested checklist with the company’s checklist indicated that the manufacturer’s suggested checklist recommended that the status of the emergency/park brake and associated warning light be checked on three separate occasions before takeoff. None of these checks appeared on the company checklist.

C.    FAA Responsibilities. Aviation safety inspectors (ASI) must review the checklists of high‑performance jet aircraft to ensure that any information or procedures in the manufacturer’s suggested checklist are included in the checklist used by the flightcrew.


A.    High-Altitude Airports. There are several high-altitude airports in the United States with approved instrument approach procedures (IAP) where the minimum descent altitudes (MDA) are greater than 2,000 feet (ft) above ground level (AGL) and/or the landing visibility minimums are greater than 3 miles. This could result in a critical situation if the weather is marginal and a pilot has failed to plan for a suitable alternate airport.

B.    Section 91.167(b). Section 91.167(b) permits a pilot to avoid the alternate airport fuel requirement. This provision is dependent upon the ceiling at the estimated time of arrival (ETA) over the airport of intended landing being forecast, for at least 1 hour before and after landing, to be at least 2,000 ft above the airport elevation and the visibility being at least 3 miles.

C.    FAA Responsibilities. During surveillance or other contacts with pilot groups, especially in high‑altitude areas, inspectors should stress the need for a careful review of the instrument approaches to airports located in mountainous terrain with respect to minimum altitudes and aircraft avionic equipment capability. Inspectors should recommend that pilots consider the need for enough fuel to divert to an alternate airport even when the weather forecasts are at or above the minimums for waiving this requirement.

1)    A number of airports have minimum altitudes below 2,000 ft and 3 miles for some IAPs that require special equipment such as a glideslope (GS) or distance measuring equipment (DME). All other IAPs at these airports have MDAs above the required minimum ceiling for foregoing the necessary fuel to reach an alternate. If there is no special equipment installed or it becomes inoperative, and the ceiling is, as forecast, about 2,000 ft AGL, the situation may necessitate that the pilot declare an emergency under instrument conditions at the destination airport.
2)    A number of airports have MDAs that are slightly (100 to 200 ft) below 2,000 ft AGL. In situations when the weather is forecast to be 2,000 ft ceiling and/or 3 miles visibility, a pilot may find upon arrival that the weather is somewhat less than forecast. If a missed approach was necessary and the prospects of the weather improving were slim, the pilot who had not included enough fuel to get to a suitable alternate might become involved in an emergency.

3-267    HAZARDS ASSOCIATED WITH CARRIAGE OF CARGO PACKED IN CARBON DIOXIDE. An incident involved a Falcon Jet’s flightcrew members who experienced dizziness and shortness of breath while awaiting takeoff clearance. The cargo on board the aircraft included items packed in solid carbon dioxide, also known as dry ice. The crew was confined in an unventilated cabin for approximately 10 minutes. The flight returned to the ramp, and the crew recovered after exiting the aircraft. The dry ice was offloaded, and the flight departed without further incident. Subsequent investigation revealed that crewmembers on other flights had also experienced these symptoms when carrying dry ice.

A.    Dry Ice as a Hazardous Material (Hazmat). Dry ice, usually in a snow-like consistency, refrigerates food, medicine, and other perishable items. Dry ice is a solid under the hazmat regulations of Title 49 of the Code of Federal Regulations (49 CFR).

1)    When transported by aircraft, contain solid carbon dioxide, a hazmat, in packaging designed and constructed to permit the release of carbon dioxide gas.
2)    One of the factors affecting the sublimation rate of this gas is the surface area of the solid carbon dioxide. The snow-type consistency of dry ice causes gas to sublimate at a much higher rate than carbon dioxide in blocks. The rate of carbon dioxide release varies with the degree of insulation used in packaging, crushed or solid form of carbon dioxide, temperature, and atmospheric pressure.
3)    Carbon dioxide is a simple asphyxiate. When conditions are high enough that there is insufficient oxygen in the atmosphere to support life, symptoms of asphyxiation may result. The signs and symptoms are those that precede asphyxia: headache, dizziness, shortness of breath, muscular weakness, drowsiness, and ringing in the ears. Immediate removal from exposure generally results in rapid recovery.

B.    Hazards of Dry Ice On Board Aircraft. The hazard associated with the carriage of dry ice aboard all aircraft is minimal under most cabin ventilation conditions. However, the concentration of carbon dioxide in an unventilated cabin area the size of a Falcon Jet or smaller can be significant. The cabin air rate of change per hour should be positive to prevent unwanted carbon dioxide concentrations when carrying dry ice. While this hazard is greater during ground operations, it is possible to have a carbon dioxide buildup in the cockpit/cabin area during flight. The buildup could be greater during periods requiring less ventilation, such as cool weather operations with the vents closed and only a small amount of heat applied.

C.    FAA Responsibilities. Inspectors should contact pilots and certificate holders who they know carry cargo packed with dry ice and discuss this issue. At present, the extent of the problem is unknown. Forward any reports of crewmembers having symptoms that possibly relate to carriage of dry ice to the Commercial Operations Branch.

1)    The FAA recommends that pilots operating aircraft with a cabin volume the size of the Falcon Jet or smaller, which are not capable of forced ventilation while on the ground, be aware of this hazard and initiate procedures to ensure there is no impairment to their ability to function. One positive solution is the use of 100 percent oxygen by the crew while taxiing and holding the aircraft before takeoff.
2)    Pilots of unpressurized small aircraft carrying dry ice should be aware of the possibility of carbon dioxide buildup during en route operations. If pilots suspect any carbon dioxide asphyxiation symptoms, they should increase the cabin ventilation. Pilots should also consider landing as soon as practical if the symptoms continue.
3)    Operators who need to carry large quantities of dry ice over long distances may wish to evaluate or monitor cockpit conditions. There are many types of carbon dioxide detection devices available.

3-268    FLAP OPERATION ON HS-125 AIRCRAFT. Two recent incidents involving flap spar damage caused by flap contact with snow and/or slush during landing have prompted a need to reemphasize compliance with the applicable instructions contained in the Hawker Siddeley crew flight manual.

A.    Lift-Dump Position. In each incident, the stress and resulting overloads were imposed when the flaps were deployed to the 75 degree or “lift-dump” position. In one case, damage to the flaps and flap spars created an additional hazard by the lateral movement outboard of the damaged flap, which in turn damaged the adjacent aileron.

B.    Crew Manual Changes. The Hawker Siddeley company has incorporated the following instructions in the crew flight manuals of HS-125 Models 3AR, 3ARA, 400, 600, and 700 when operating on a runway with deep puddles, slush, snow, or ice.

1)    Ensure as far as possible that the landing does not result in a go-around after touchdown.
2)    After every such landing or aborted takeoff, avoid retracting the flaps, if practicable. Examine the top and bottom surfaces of the flaps and adjacent structures for damage, preferably with the flaps in the lift-dump position. Also, ensure that there is no packed slush, snow, or ice between the flap and wing structures.
3)    If the flaps are confirmed as damaged after examination, report the fact to the person responsible for the aircraft’s maintenance at the first convenient opportunity, but not later than the next Service A inspection. Examine each flap inboard hinge bolt for signs of overloading.

C.    FAA Responsibilities. Principal Operations Inspectors (POI) should contact all known operators of the HS-125 models indicated above and advise them of the hazards associated with operations onto snow- or slush-covered runways with this type of aircraft. Request that operators review the specific instructions in the crew flight manual regarding this hazard with their flightcrews.

3-269    LANDING ON WET OR SLIPPERY RUNWAYS. Water, ice, or snow on a runway can seriously affect aircraft ground controllability and braking efficiency. In the case of standing water, as the speed of the aircraft and the depth of the water increase, the water layer builds up an increasing resistance to displacement, resulting in the formation of a wedge of water beneath the tire. The vertical component of this resistance progressively lifts the tire, decreasing the area in contact with the runway until, with certain aircraft configurations and water depths, the tire is completely out of contact with the runway surface and starts hydroplaning on a film of water. In this condition, the tires no longer contribute to directional control, and braking action is nil.

A.    Types of Hydroplaning.

1)    Dynamic hydroplaning can occur when there is standing water on the runway surface. Water about 1/10 inch deep acts to lift the tire off the runway as explained above.
2)    Viscous hydroplaning occurs because of the viscous properties of water. The tire cannot penetrate a thin film of fluid more than 1/1000 inch deep and the tire rolls on top of the film. Viscous hydroplaning can occur at a much lower speed than dynamic hydroplaning, but it requires a smooth surface.
3)    Reverted rubber hydroplaning requires a prolonged, locked wheel skid, reverted rubber, and a wet runway surface. Rubber that has reverted to the surface during previous landings contaminates most runways. This reverted rubber acts as a seal between the tire and the runway and delays water exit from the tire footprint area. The water heats from friction becoming steam, and the steam supports the tire off the pavement.

B.    Hydroplaning Tests. From the data obtained during hydroplaning tests, the minimum dynamic hydroplaning speed of a tire has been determined to be 8.6 times the square root of the tire pressure in pounds per square inch (psi). For example, the Learjet main tire has a pressure of 115 psi, and its calculated hydroplaning speed is 92 knots (kts). It is important to note that the calculated speed is for the start of the dynamic hydroplaning. Once hydroplaning has started, it may persist to a significantly slower speed, depending on the type of hydroplaning.

1)    A joint FAA/National Aeronautics and Space Administration (NASA)/United States Air Force (USAF) Runway Research Program was conducted to establish the degree of stopping distance correlation between jet aircraft and ground friction measurement vehicles.
2)    Although the aircraft used for the program were transport category aircraft (B727 and DC-9), because of these tests, the following general procedures are suggested when landing any aircraft on slippery or wet runways:
a)    Fly a stabilized approach without excessive airspeed. Touch down at the proper point and avoid holding the airplane off.
b)    If it is not possible to establish a zero-drift condition before touchdown, execute a missed approach.
c)    If available, activate the spoilers as soon as possible after main gear touchdown. With automatic spoiler systems, be prepared to deploy the spoilers manually.
d)    Immediately lower the nosewheel to the surface and maintain wheel loading by forward pressure on the control column.
e)    If available, apply reverse thrust on all engines.
f)    Maintain directional control, primarily with rudder and nosewheel steering. Use differential braking as needed.
g)    Apply light to moderate brake pedal pressure.
h)    If directional control becomes a problem while in reverse thrust, reduce reverse thrust on all engines and, if necessary, return them to forward thrust.
i)    Do not attempt to turn off a slippery runway until reducing speed sufficiently to turn without skidding.

C.    FAA Responsibilities. Inspectors with program responsibility for airman certification and testing should review the adequacy of pilot training and competence with respect to landing on slippery runways and the phenomenon of hydroplaning. Pilot training programs should cover these subject areas with emphasis on the operational procedures that are essential to a successful landing (i.e., speed control (stabilized approach), touchdown point, and the use of spoilers/speed brakes, wheel brakes (including use of antiskid limitations), and reverse thrust).


A.    Accident History. In an accident several years ago, a Learjet overran the end of a runway, traveled off a 90-ft bluff, and was destroyed by impact and fire. The accident killed four passengers and two crewmembers. The runway was 3,240 ft long and 100 ft wide with 120-ft displaced thresholds. The FAA‑approved flight manual for the Learjet indicated a requirement of 3,100 ft for landing distance based on airport elevation, runway gradient, temperature, and wind at the time of the accident.

B.    FAA Responsibilities. Inspectors should contact operators of transport category aircraft in General Aviation Operations (GAOP) and discuss the use of minimum landing runway lengths that will provide the safety margin required by 14 CFR part 121 or 135. If it is not possible for General Aviation (GA) operators to use these safety margins, the inspector should encourage the operator to establish the use of safety margins consistent with the performance of the emergency braking system of the aircraft.

1)    It is important for pilots to preplan for brake failures, including decisions to abort a landing after touchdown.
2)    Review the use of emergency brakes and other deceleration devices during preflight planning.
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3)    Many transport category airplanes have performance charts included in the Airplane Flight Manual (AFM). These performance charts depict minimum landing distance with the margins required by parts 121 and 135 already calculated. Encourage the use of these charts, since use of the more conservative values when flight planning will result in crews choosing runways with a greater margin of safety.

3-271    ALTIMETER SETTINGS FOR BAROMETRIC PRESSURE ABOVE 31.00 inHg. There is no need to test altimeters for barometric pressures exceeding 31.00 inches of mercury (inHg); most are not capable of an adjustment to exceed this value.

A.    Characteristics of High Barometric Pressure. The Air Traffic Procedures Advisory Committee (ATPAC) identified a need to ensure common pilot/controller understanding of aircraft operations in areas where the barometric pressure exceeds 31.00 inHg. The committee, with consultation from the Flight Standards Service and the Air Traffic Organization (ATO), recommended that the FAA advise the aviation community of the effects of high barometric pressure on aircraft operations.

1)    The atmospheric conditions that produce barometric pressure in excess of 31.00 inHg are a cold, dry air mass. The associated ceiling and visibility are essentially unlimited except for local conditions such as smoke or ice fog.
2)    When the actual barometric pressure is greater than the altimeter setting, the indicated altitude will be lower than the actual altitude. The effect of cold temperature is in the opposite direction. The two variables, pressure and temperature, tend to nullify each other.
3)    A paragraph was incorporated into the Aeronautical Information Manual (AIM) advising that ATC will announce an altimeter setting of 31.00 inHg (“Three One Zero Zero”) any time the barometric pressure equals or exceeds that value. The actual barometric pressure will be provided upon request.

B.    FAA Responsibilities. Inspectors should ensure that the aviation community is aware of the AIM material and the effects it has on their operations. Place special emphasis on advising operators at remote airports that it may not be possible to set field elevation before departure when these atmospheric conditions exist.

3-272    OPERATION ON CLOSED RUNWAYS/TAXIWAYS. Reports of aircraft operating on closed runways/taxiways indicate a need for increased emphasis on the potential problems associated with this type of operation.

A.    Notification of Conditions Affecting Safety. Airport operators are responsible for establishing and using procedures for the immediate notification of airport users and the FAA of any conditions adversely affecting operational safety.

1)    Airport operators have the authority to close an airport, or any of its runways, when they determine an area to be unusable or unsafe for aircraft operations. Airport operators are the primary authority for originating, by Notices to Airmen (NOTAM) or other means, information to airmen concerning unsafe conditions or other operational limitations on their airports.
2)    In the case of airports certificated under 14 CFR part 139, the regulation requires dissemination of information concerning airport conditions affecting safe aircraft operations to air carrier users of the airport.

B.    Operations During Closure. Airport operators have reported instances of aircraft operations on their airports contrary to the notices of closure or other restrictions because of unusable or unsafe conditions. The airports involved have been both certificated and noncertificated airports. The aircraft involved have been both air carrier and GA aircraft.

C.    Accident History. Analyses of past accidents and incidents have identified the following situations that have contributed to hazardous operational conditions on airport areas:

1)    Holes, obstacles, loose pavement, or debris on or near operations areas.
2)    Heavy equipment, stationary or mobile, operating near airport operations areas or in safety areas.
3)    Relatively low visibility units such as cranes, drills, and the like in critical areas such as approach zones.
4)    Crews of workers, who may not be highly visible, near runways or taxiways.
5)    Mounds of earth, construction material, temporary structures, and other obstacles in proximity to operations areas and approach zones.
6)    Safety area encroachments, improper ground vehicle operations, and unmarked or uncovered holes and trenches near aircraft operating surfaces.

D.    Permanent Runway/Taxiway Closings. When an airport operator permanently closes a runway or a taxiway, the lighting circuits are disconnected.

1)    On a closed runway, obliterate the threshold markings, runway designation marking, and touchdown zone (TDZ) markings, and place crosses at each end and at 1,000-ft intervals.
2)    Place a cross at each entrance of the closed taxiway.

E.    Temporarily Closed Runways/Taxiways.

1)    Treat temporarily closed runways in the same manner as permanently closed runways, but do not obliterate markings. Place temporary crosses only at the runway ends on top of the runway numbers.
2)    The use of barricades with alternate orange and white markings, supplemented with flags, indicates temporarily closed taxiways. For night operations, use flashing yellow lights.
3)    During night operations, an airport with a closed/obstructed runway may still have the airport rotating beacon in operation.
4)    Identification of temporary runway threshold displacements should be located outboard of the runway surface. This could include outboard lights, runway end identification lights (REIL), and markings.

F.    Pilot Expectations. If a NOTAM has not been issued advising that a runway is closed, and if there is no information to the contrary, a pilot should be able to expect that the runway is free of unusual conditions of a hazardous nature. However, if a NOTAM has been issued advising that the runway is undergoing maintenance and the entire surface is unusable or unsafe, the pilot has no way of knowing what hidden defects the pavement may contain or what sort of activity may suddenly occur on a previously unoccupied portion of the surface.

G.    Closed Runway Information. When a runway or other area will close, the airport operator provides information to the local ATC facility so that one may issue a NOTAM.

1)    Inspectors should review the NOTAM system detailed in the AIM and particularly note the NOTAM information that one distributes locally. Do not attach NOTAM information to the hourly sequence reports.
2)    Maintain a separate file of NOTAMs at each Flight Service Station (FSS) for facilities in its area only.
3)    Specifically request NOTAM information for other FSS areas directly from the FSS that has responsibility for the airport concerned. The responsibility for obtaining this information rests with the pilot in command (PIC) during preflight planning. Operation on any closed and NOTAM-listed airport area that results in an accident, incident, or other hazardous occurrence is grounds for enforcement action.

H.    FAA Responsibilities. When a report of, or a complaint about, an aircraft operating on a closed runway or other airport surface is received, the inspector should make a record of the complaint in detail (see Volume 7, Chapter 5).

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1)    The inspector should record as many specific details as possible in order to determine if a hazardous operation took place (see Volume 7, Chapter 5).
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2)    The follow-up investigation should be conducted with an emphasis on the competency of the airman involved (e.g., recognition of hazardous situations, awareness of conditions affecting the operation, and ability to obtain information necessary for conduct of safe operations). If necessary, the inspector should begin an enforcement investigation (see Volume 14).
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3)    During routine contact with airmen (participation in safety seminars, pilot counseling, flight instructor seminars, discussions with pilot schools, etc.), inspectors should disseminate this information and offer appropriate cautions, while emphasizing that the safety of any flight is ultimately the responsibility of the PIC.

3-273    USE OF ATC SERVICES DURING NIGHT/MARGINAL VISUAL FLIGHT RULES (MVFR) CONDITIONS. The use of ATC services may reduce the potential for in-flight, terrain-type accidents and in turn greatly enhance safety. An NTSB analysis of aircraft accidents in night and MVFR conditions indicated that the use of available ATC services by pilots operating in these conditions would greatly enhance safety.


A.    Incident History. Incidents where the flightcrews improperly identified and reacted to cockpit light indications stressed the need for this guidance. One event occurred during an approach when an engine ignition light came on. Without further verification, the flightcrew assumed that the engine had failed and continued the approach. During the attempted single-engine missed approach, the flightcrew lost aircraft control and crashed. Communications between the pilots during this accident indicated lack of situational awareness as well as misidentification of the problem. It would have been possible to avoid this accident if the flightcrew correctly analyzed the situation and took proper corrective action. Once they incorrectly assumed the engine had failed, the crew then complicated the situation by failing to accomplish the correct engine shutdown procedures and plan for a single-engine approach. The investigation revealed that during training the only time the crew experienced an illuminated ignition light was in conjunction with an engine failure. Flightcrews received no exposure to circumstances that may cause the ignition light to illuminate, other than an engine failure, during training. This may have conditioned the crew to regard the light only as an engine failure event.

B.    Following the Emergency Checklist. In a separate event, the crew was confronted with an illuminated start valve light, followed by fire indication lights, shortly after takeoff. The crew only completed the first two steps of the emergency procedure checklist (autothrottle: off and throttle: idle), before stopping to brief the flight attendants (F/A). Failure to complete the engine fire shutdown procedure in a timely manner led to additional problems during the subsequent approach and landing. Although a captain may do whatever he or she judges most important to mitigate an emergency situation, given the information available to the flightcrew at the time, it is important to stress that interrupting an emergency checklist should be strongly discouraged as a matter of safety policy unless a greater emergency exists.

C.    FAA Responsibilities. Inspectors responsible for approving and reviewing training programs are encouraged to review their operator’s training curriculums for emphasis of the following points:

1)    Initial and recurrent training programs should provide a broad range of engine failure scenarios, including failures that one may misinterpret as an engine failure.
2)    Once the flightcrew verifies an engine failure, they should take action to accomplish the correct shutdown checklist and properly plan for an engine-out approach and possible go-around.
3)    Emphasize the importance of the emergency/abnormal checklist. Completion of its checklist should be deliberate and methodical; it should not be rushed or interrupted for routine events until it has been completed.


A.    Description. Flight envelope protection varies by aircraft type and, in some instances, by series. These systems typically employ automated interventions in an attempt to prevent the aircraft from exceeding predetermined limitations. They include, but are not limited to:

1)    Fully Integrated Envelope Protection. Fully integrated envelope protection typically employs protection algorithms as part of a larger set of flight control laws found on fly-by-wire aircraft. In these aircraft the flight control system actively limits flight control position downstream of pilot input in order to keep the aircraft from exceeding predetermined envelope limits. This type of envelope protection may have high speed/low speed, bank angle, and load factor protections, in addition to angle of attack (AOA) protection.
2)    Deterrent Envelope Protection. Deterrent (or force feedback) envelope protection typically employs protection indirectly by applying force feedback cues, such as force gradients or steps, to the pilot in an effort to deter the pilot flying (PF) from continuing a control input that would cause the aircraft to exceed the normal flight envelope.
3)    Stick Pusher. Stick pusher typically employs mechanical means to lower the aircraft’s AOA if a predetermined value is exceeded.
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B.    FAA Responsibilities. Comprehensive information regarding envelope protection is available from the aircraft manufacturer. Air carriers, program managers, and operators must adequately train pilots on the varied effects of envelope protection during normal, abnormal, and emergency situations. For part 121 operations, the requirements are listed under part 121, §§ 121.419(a)(2)(v), 121.424(a), 121.427, 121.441; part 121 appendix E, and appendix F; and §§ 121.913 and 121.915 for Advanced Qualification Programs (AQP). For part 135 operations, the training requirements are listed under part 135, §§ 135.345(b)(5), 135.347, and 135.351 and checking under § 135.293. For 14 CFR part 125 operations, the initial and recurrent pilot testing requirements are listed under part 125, § 125.287(a)(2). For part 91 subpart K (part 91K) operations, the training requirements are listed under §§ 91.1101(b)(5), 91.1103(a), and 91.1107; the pilot testing requirements are listed under § 91.1065(a)(2). Consideration of the Flight Standardization Board Report (FSBR) is recommended. This report may contain additional training requirements specific to aircraft type not contained in 14 CFR or manufacturer documentation. Accordingly, when reviewing and approving operator pilot training programs or curriculums, POIs and Training Center Program Managers (TCPM) must ensure the effects of envelope protection during normal, abnormal, and emergency operations are adequately covered in both ground and flight training.


A.    Accident History. Studies conducted by the Flight Safety Foundation (FSF) and published in June 2013 have shown the majority of accidents over the last 10 years occurred during the approach, landing, and go-around flight phases. In 2011, 68 percent of accidents in commercial aviation (63) occurred during these phases of flight. Approach and landing accidents remain the highest ranked categories of air carrier fatal accidents. The NTSB found that pilots unwilling to execute a required go-around and/or missed approach when necessary was a cause in some approach and landing accidents. The FSF studies found that the lack of a go‑around decision is the leading risk factor in approach and landing accidents and is the primary cause of runway excursions during landing; in fact, less than 5 percent of unstabilized approaches lead to a go-around. They concluded that no other single decision (go-around decision) could have as great an impact on the overall aviation industry accident rate.

B.    Policy and Procedures. Inspectors of parts 91K, 121, 125, and 135 operators responsible for approving/accepting manuals/procedures must require operators to publish or reinforce written policies and procedures emphasizing:

1)    That the PF, the pilot monitoring (PM), or Flight Engineer (FE), as applicable, should be able to assess the approach and call for a “go-around” if a stable approach cannot be continued to a safe touchdown in the TDZ for the intended landing runway. If either the pilot or the FE believes that the parameters for stabilized approach criteria as stated in their approved/accepted manual/procedure are not met during the approach, a flightcrew member must call for a “go-around.”
2)    The PF’s immediate response to a “go-around” callout is the execution of a go-around maneuver and/or missed approach, as applicable. Also note that, depending on the phase of flight, a Crew Resource Management (CRM) discussion on the go-around/missed approach decision may not be possible.
3)    No punitive measures for flightcrew members who make a go-around call for the sake of safety.

C.    Training Programs. Inspectors responsible for approving/accepting flightcrew training programs must require operators to incorporate go-around/missed approach policies and procedures during ground and flight training for all training categories.


A.    Description. Section 91.407(b) requires that an OCF be performed after maintenance, preventive maintenance, rebuilding, or alteration whenever that work may have appreciably changed the aircraft’s flight characteristics or could affect its operation in flight. An OCF is also conducted, as decided by the operator, to determine whether an aircraft airframe, engine(s), accessories, or equipment is functioning according to established standards while the aircraft operates in its intended environment. These checks should be conducted with only the necessary personnel on board to complete the check. POIs and Principal Maintenance Inspectors (PMI) of parts 91K, 121, 125, and 135 operators are jointly responsible for oversight of OCF activities.

B.    Background. OCFs may pose a higher risk of producing an accident or serious incident than revenue flights or other flying. This is because OCFs are routinely undertaken by flightcrews who are not aware of the risks associated with any given nonstandard flight. Compared to the routine of normal operations, OCFs pose a higher risk due to the following:

    An unfamiliar environment with a significantly modified context for standard operating procedures (SOP), in particular, the possibility in many cases of an absence of the usual en route period of relative inactivity.

    The apparent willingness of a minority of flightcrews making nonstandard flights to apply less rigor than usual to the use of prevailing SOPs.

    The procedures documented within the Operations Manual and implemented by an aircraft operator for such flights are inadequate.

C.    Risk Mitigation. The particular risk associated with an operator’s OCFs should be mitigated to a standard risk level associated with revenue flights through the application of its Safety Management System (SMS) and related Safety Assurance System (SAS).

1)    The OCF must meet the airworthiness and operational requirements of § 91.407(a) and (b).
2)    The Operations Manual should contain a generic but comprehensive supplementary brief that covers the operation of each type of OCF.
3)    If the check schedule requires operation of intentionally degraded aircraft systems, then a task‑specific program of initial and recurrent training should be mandated for the operating crew.
4)    Flightcrew allocated to operate the flight should be required to fly a similar detail in a simulator not later than their most recent simulator proficiency check, unless a similar OCF profile has been flown since that time.
5)    Appropriate additional time should be planned for a preflight briefing for all those persons who will occupy flight deck seats.
6)    The role of any persons to be carried who will have access to the flight deck during the flight should be defined in writing and form part of the overall procedures for the conduct of the OCF.
7)    Supplementary or amended checklists should be provided if the sequence of flightcrew actions will not follow that covered by sole use of the normal and/or non-normal checklists; the use of these checklists should form part of any simulator training requirement.

D.    Policy and Procedures.

1)    The company’s Operations Manual should include a definition of OCF appropriate to the normal business of the operator. This should state that all SOPs apply unless specifically suspended or supplemented by a specific instruction.
2)    A Flight Operations Risk Assessment specific to the OCF tasks should be done prior to any OCF. Everyone involved in the preparation and operation of any flight covered by this risk assessment should then work to its detailed assumptions and requirements. The operator’s procedures should be cross-checked by a qualified person as provided in its SMS program.

E.    POI and PMI Responsibilities.

1)    Review Procedures. Review the operator’s written procedures to ensure that the following actions occur related to the OCF:
a)    The maintenance performed on the aircraft has been approved for return to service by evidence of an appropriate maintenance record entry as required by 14 CFR part 43, § 43.9 or § 43.11.
b)    Only required crewmembers are authorized on board for the flight.
c)    Prior to the flight, the crewmembers have been informed of all appropriate information regarding the maintenance that was performed on the aircraft, the in-flight tasks required to complete the OCF, and known possible adverse operating characteristics of the aircraft as a result of a failed check.
2)    Review Maintenance Record Entries and Airmen Qualifications. Review the aircraft maintenance record entries and ensure that appropriately rated airmen performed the work and completed the OCF.
a)    Prior to the flight, the aircraft must be approved for return to service with respect to work performed. The work performed must be conducted by an appropriately certificated entity.
b)    Prior to the flight, a record of maintenance must be entered as required by § 43.9 or § 43.11.
c)    When an OCF is required, the maintenance record entry should include a description of the checks required during the OCF.
d)    The pilot(s) performing the OCF must be appropriately certificated and rated.
e)    The pilot(s) should conduct the required operational checks to verify the proper operation and flight characteristics of the aircraft related to the maintenance that was performed.
f)    Following completion of the flight, the pilot performing the OCF should log the flight in the aircraft’s records indicating the results of the checks.
Indicates new/changed information.

RESERVED. Paragraphs 3-278 through 3-279.