孔子的故事简短U.S. Department of Transportation Federal Aviation Administration Advisory Circular
1p空调多大功率
Subject: Runway Overrun Prevention Date: 11/06/07
Initiated by: AFS-800 AC No: 91-79 Change:
农村土地承包1.PURPOSE. This advisory circular (AC) provides ways for pilots and operators of
turbine-powered airplanes to identify, understand, and mitigate risks associated with runway overruns during the landing pha of flight. It also provides operators with detailed information that may be ud to develop company standard operating procedures (SOP) to mitigate tho risks.
2.AUDIENCE.
a.This document provides guidance to flightcrews, aircraft operators, certificate holders, program managers, training providers, and pilot examiners that conduct turbine-powered airplane operations or provide support rvices to such operations. The concepts also apply to other types of airplane operations, and some operators must adhere to more restrictive guidance bad on their applicable operations or management specifications.
b.Turbine aircraft operators, certificate holders, program managers, training centers, and other support providers should adopt the recommended procedures found in this AC to help mitigate the risk of runway overruns. This should include the creation or revision of SOP, training programs and courware, and company policies and procedures to reinforce the risk mitigation strategies. For Title 14 of the Code of Federal Regulations (14 CFR) part 91
subpart K, part 121, 125, or 135 operators, the procedures and programs should be incorporated into the certificate holder’s or program manager’s operations manual system as appropriate. Part 91 turbine operators are encouraged to review this material and to include it in the applicable company documents.
3.RELATED READING MATERIAL (current editions).
a.AC 25-7, Flight Test Guide for Certification of Transport Category Airplanes.
b.AC 60-22, Aeronautical Decision Making.
c.AC 120-71, Standard Operating Procedures for Flight Deck Crewmembers.
d.AC 121.195-1, Operational Landing Distances for Wet Runways; Transport Category Airplanes.
e.Notice 8000.340, Revision of Order 8400.10, Volume 4, Chapters 1 and 2.
AC 91-79 11/06/07
f.FAA-H-8083-3A, Airplane Flying Handbook.
4.BACKGROUND. According to Federal Aviation Administration (FAA) and National Transportation Safety Board (NTSB) information, runway overruns during the landing pha of flight account for approximately 10 incidents or accidents every year with varying degrees of verity, with many accidents resulting in fatalities. The FAA is working in partnership with industry to develop strategies to reduce the number of landing overrun incidents/accidents. A review of runway overrun events indicates that most occur due to either a lack of or nonadherence to SOP. The events continue to occur despite efforts by the FAA and industry to ensure that operators develop SOPs and that flight crewmembers are properly trained and operate in accordance with the SOPs. Therefore, an emphasis on SOP development and a risk mitigation approach is employed in this AC.
a.Focud training and testing of crewmembers along with practical planning tools are the keys to avoiding runway overrun events. This emphasis on training and checking should be targeted at initial pilot certification as well as recurrent training and checking events. The training and checking should
not be merely academic in nature. The events should emphasize real world aeronautical decision making and u scenario bad prentations in order to increa pilot recognition of high risk landing operations.
b.Proper identification of the risks will help pilots employ mitigation strategies or eliminate certain risks prior to the landing event.
纽约吃喝玩乐c.Operators are responsible for developing SOPs, and all pilots are responsible for ensuring that they are well-trained, qualified for the intended flight, and meet all of the regulatory requirements for the flight. This responsibility includes the lf-discipline to follow company SOPs and/or industry best practices and safety procedures that can prevent runway overrun incidents/accidents regardless of the level of managerial or government oversight. Even the best procedures are ineffective if they are not followe
d.
5.DISCUSSION. This AC is divided into three areas. The first area, in paragraph 6, discuss hazards associated with runway overruns. The cond area, in paragraph 7, prents some risk mitigation strategies associated with the hazards. The strategies include the development of SOP
s, elements of training cour content, checking techniques, and some rules-of-thumb for evaluating the effects of certain conditions on landing distance. The third area, the appendices, provides a centralized source of supporting information uful in developing the training suggested.
6.HAZARDS ASSOCIATED WITH RUNWAY OVERRUNS. In order to develop risk mitigation strategies and tools, hazards associated with runway overruns must be identified. A study of FAA and NTSB data indicates that the following hazards increa the risk of a runway overrun:
• A nonstabilized approach,
•Excess airspeed,
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AC 91-79
• Landing beyond the intended touchdown point, and • Failure to asss required landing distance to account for slippery or contaminated t practices for stabilized approaches will always be the first line
of defen in preventing a runway overrun. A discussion of stabilized approaches is located in Appendix A, par runway conditions or any other changed conditions existing at the time of landing.
a. Nonstabilized Approach. Safe landings begin long before touchdown. Adhering to the SOPs and bes agraph 3.
b. Excess Airspeed. V REF is the reference landing approach speed at the landing screen height of 50 feet. This speed is ba from which to calculate speeds ud during landing. The reference speed is calculated as a margin over the stall speed. Many part 25 airplanes are certified using a SRO REF V 23.1of V ud by pilots as a × where V SRO is the stall speed for the landing configuration. While there are specific circumstances, such as strong gusty wind conditions and potential wind shear environments where adjusting the approach speed is appropriate, it is often done in an arbitrary manner that adverly affects the landing performance of the airplane. The manufacturer’s recommended procedure for many part 25 airplanes is to u an approach sp of V eed the s the risk of a
runway overrun. It is important to understand how the approach speeds are determined and to fly them ing airplane does not touch down at the intended touchdown point or an allowance is not made
for the longer touchdown point, it will not be possible to ach d. Failure to Asss Required Landing Distance Bad on Conditions at Time of Arriva ance of descent. If airport and associated runway surface conditions are forecast to worn, develop an alternate plan of d to account for pilot technique, atmospheric and runway conditions, and other items to ensure that the flight is not dispatched to a destination where it will be unable to land. As part of the
REF +5 for both manual landings and autolands. If the additional speed is not bled off by landing screen height of 50 feet., the added speed is not accounted for in the calculation of runway landing distance required, and the added speed significantly increa accordingly to obtain the desired landing performance of the airplane.
c. Landing Beyond the Intended Touchdown Point. Aircraft Flight Manual (AFM) landing performance data usually assumes a touchdown point determined through flight test procedures outlined in AC 25-7A. If the ieve the calculated landing distance.
l.
(1) Conditions at the destination airport may change between the time of departure and the time of arrival. SOPs should include a procedure for asssing the required landing dist bad on the conditi
ons that are known to exist as you near the destination. As a recommended practice, calculate and discuss the landing distance required after receipt of the automated terminal information rvice (ATIS), during the descent briefing, and prior to the top action in the event that a misd approach or go around becomes necessary.
(2) The unfactored landing distances in the manufacturer-supplied AFM reflect
performance in a flight test environment that is not reprentative of normal flight operations. The operating regulations require the AFM landing distances to be factored when showing compliance with the predeparture landing distance requirements. The factors are intende Par 6 Page 3
AC 91-79 11/06/07 operator’s Safety Management System (SMS) and SOP, the FAA recommends using either factored landing distances or adding a safety margin to the unfactored landing distances when asssing the required landing distance at the time of arrival. This landing safety margin should not be confud with the regulatory predeparture runway requirements.
发圈
NOTE:Operators should u the appendices, which contain detailed
information about all of the hazards, to develop their SOPs. The 15 percent
safety margin additive recommended by the FAA is intended only to account
for slight variations in achieved performance.
7.RISK MITIGATION.
a.SOPs. Well-developed SOPs are the primary risk mitigation tools ud to prevent runway overruns. The procedures must be relevant and focud on the end ur—the flightcrew. Once SOPs are developed, it is imperative that the flightcrew execute them faithfully to help prevent runway overruns. As a minimum, the SOPs should contain the following procedures directly related to runway-overrun prevention:
•Stabilized approaches, including procedures for executing a go-around if the approach parameters are outside of the stabilized approach criteria,
•Landing distance reasssment at the time of arrival, and
•U of brakes and other deceleration devices.
b.Training. An effective training program is a condary tool that provides academic knowledge abou
t the subjects related to landing performance. Effective training also reinforces the practical application of the knowledge and the associated SOPs in the cockpit. At a minimum, the operator’s training program should contain the following elements directly related to runway-overrun prevention:
•SOPs-operator specific;
•Stabilized approaches;
•Source and conditions of landing distance data contained in aircraft flight manuals or FAA approved destination airport analysis (airplane type specific);
•Landing distance calculation—preflight;
•Landing distance calculation—reasssment at time of arrival;
•Conquences of excess airspeed;
•Conquences of landing beyond the intended touchdown point;
•U of brakes to include autobrakes, if installed, and deceleration devices (airplane type specific);
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11/06/07 AC
91-79 •Landing distance rules of thumb; and
•Reasons to initiate a go-around and execution of the go-around maneuver.
This training should be incorporated into type rating training, air carrier training, and into
光学实验14 CFR part 61, § 61.55 training conducted at a 14 CFR part 142 training center.
c.Checking. Effective checking that emphasizes the subject of aircraft landing
performance is an esntial tool in preventing runway overruns. Examiners, instructors, and
check airman should specifically stress aeronautical decision making and risk management
scenarios that incorporate potential runway overruns during the following evaluations:
一到三年级的古诗
•Type Rating Practical Tests;
•Pilot in Command Proficiency Checks (14 CFR parts 61, 91K, 121, 125, 135);
•Pilot Proficiency and Competency Checks (parts 61, 91K, 121, 125, 135); and
•Part 61, § 61.56, Flight Reviews.
NOTE:Runway overrun mitigation strategies should be introduced during
flight training and checking to ensure the applicant can apply the principles
in a real world environment. For example, the introduction of a scenario
incorporating an unexpected change in wind direction, or a change in wind
speed, the landing runway, or a change in the runway surface condition
would require the applicant to reasss the landing performance. The
instructor or the examiner would quickly determine if the applicant has a
grasp of the principles and their effect on the safety of the landing. Specific
年夜饭作文800字
questions should be asked during oral or written examinations to ascertain
the applicant’s ability to apply the knowledge in a practical matter.
d.Rules of Thumb. The following “rules of thumb” are included to assist the pilot in the
application of basic knowledge in order to reinforce the principles associated with runway
overrun prevention.
NOTE:The rules of thumb cannot replace the information contained in
the AFM. They are provided to help the flight crewmember recognize the
possible increa in risk associated with certain conditions.
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