1111打印 確定下一代航路危險天氣限制類型運行概念tenny lindholm

1、AIAA 2009-69949th AIAA Aviation Technology, Integration, and Operations Conference (ATIO)and Air 21 - 23 September 2009, Hilton Head, South CarolinaConcept of Operations for Addressing Types of En Route Hazardous Weather Constraints in NextGenTenny Lindholm 1Science and Technology in Atmospheric Res

2、earch Institute, Boulder, CO, 80301Jimmy Krozel Ph.D.2 andMetron Aviation, Inc., Dulles, VA, 20166Joseph S. B. Mitchell, Ph.D. 3State University of New York, Stony Brook, NY, 11794In this paper, we present a possible Concept of Use that addresses hazardous weather constraints in the Next Generation

3、Air Transportation System (NextGen). Weather hazards, including the “types” of convection, turbulence, icing, and other weather effects are classified into hard and soft constraints. Hard constraints are formed by weather hazards that no aircraft can safely fly through (e.g., severe convection, turb

4、ulence or icing). Soft constraints are formed by weather hazards which some pilots or airlines decide to fly through while others do not (e.g., moderate turbulence or icing). We consider two aircraft “classes”: Class 1 aircraft that avoid both hard and soft constraints, and Class 2 aircraft that avo

5、id hard constraints but are willing to fly through soft constraints. The Concept of Use is based on a Weather Impact Interaction Grid which relates the type of weather hazard to the class of aircraft. The Weather Impact Interaction Grid and aircraft 4 Dimensional Trajectories are analyzed to identif

6、y Flow Constrained Areas (FCAs) for which traffic flow management must organize flows of traffic with restrictions placed on entry into FCAs in order to safely maximize FCA throughput. We first describe the operational environment for air traffic management in the National Airspace System in NextGen

7、, and then the Concept of Use and Scenarios are described.NomenclatureGTG IOC MAPMoG4D4DT ADDS AFP AIRMET ANSP AOC CDA CDR CIPDST FCA FIP GA GPS4 Dimensional 4D TrajectoryAviation Digital Data Service Airspace Flow ProgramGraphical Turbulence Guidance Initial Operational Capability Monitor Alert Par

8、ameter Moderate or GreaterNational Airspace System NextGen Net-enabled Weather Pilot ReportRequired Navigation Performance Significant Meteorological Information Strategic Plan of OperationsSystem-Wide Information Management System-Wide Optimization and Planning Trajectory-Based OperationsTraffic Fl

9、ow Management Trajectory ManagementAirmens Meteorological Information Air Navigation Service Provider Airline Operations Control Continuous Descent ApproachCoded Departure Route Current Icing Product Decision Support Tool Flow Constrained Area Forecast Icing Potential General AviationNAS NNEW PIREP

10、RNP SIGMET SPO SWIM SWOP TBO TFM TMGlobal Positioning System1 Project Manager, General Aviation Program, 3125 Sterling Circle, Suite 1072 Senior Engineer, Research and Analysis Department, 45300 Catalina Court, Suite 101, AIAA Associate Fellow3 Professor, Department of Applied Mathematics and Statis

11、tics, Stony Brook University1American Institute of Aeronautics and AstronauticsCopyright 2009 by the American Institute of Aeronautics and Astronautics, Inc.The U.S. Government has a royalty-free license to exercise all rights under the copyright claimed herein for Governmental purposes. All other r

12、ights are reserved by the copyright owner.I.Introductionhe Next Generation Air Transportation System (NextGen)1-4 Concept of Operations and NextGen Weather Concept of Operations5 describe how weather hazard mitigation is envisioned for the future of the NationalTAirspace System (NAS).NextGen is base

13、d on the foundation of Trajectory Based Operations (TBO) and Trajectory Management (TM).They apply any time an air vehicle is in a 4-Dimensional (4D) environment; that is, from liftoff to touchdown, as described by 4D Trajectories (4DTs).The Air Navigation Service Provider (ANSP) will handle both in

14、dividual 4DTs and aggregate flows representing the trajectories of many aircraft. For the management of convection, turbulence, and icing constraints, flexible 4D route definitions allow traffic flows to be shifted as necessary around regions of airspace constrained by weather hazards to enable more

15、 effective weather avoidance and manage demand into and out of the arrival/departure environment. Capabilities for managing airspace structures include a common mechanism for implementing and disseminating information on the current airspace configuration to ensure that all aircraft meet the perform

16、ance requirements for any airspace they enter. The Concept of Use defines a 4D Flow Constrained Area (FCA) to specify that special requirements apply for aircraft entering into the FCA and that flows are designed to optimize the FCA capacity. Furthermore, it is up to the users to specify their indiv

17、idual flight limitations and preferences as inputs to flight planning and execution, and flight operators may dynamically update these features. With this input, the ANSP can support 4DTs tailored to individual flight preferences.When the demand is high relative to the available capacity of an airsp

18、ace, the ANSP may implement “flow corridors” for large numbers of separation-capable aircraft traveling in the same direction on very similar routes (Figure 1). Flow corridors consist of long tubes or “bundles” of near-parallel 4DTs with high traffic throughput across an airspace. The airspace for a

19、ircraft operating in flow corridors is protected; aircraft not part of the flow do not penetrate the corridor. The use of flow corridors within FCAs is a key component of this Concept of Use that addresses a variety of weather constraints. In NextGen, challenges face the NAS as more precise weather

20、information is integrated into Decision Support Tools (DSTs) and weather is assimilated into NextGen decisionloops for ATM:First, weather information is essential for effective ATM DSTs, since many forms of hazardous weather translate into constraints on the NAS6,7.Weather products will be 4D in spa

21、ce and time so that anFigure 1. Flow corridors group large quantities of aircraft flying in the same direction.aircraft 4DT can be related to 4D weather constraint information.Even with much improved resolution and precision in weather forecasts, weather information will still have some degree of un

22、certainty.Given the uncertainty, an operational concept for the use of integrated weather products is essential to explore both automated and semi-automated DSTs (they will be different).To take advantage of the uncertainty characteristic of weather information, probabilistic weather forecasts are n

23、eeded for basing decisions on expected value (or cost) of a particular course of action. This concept is familiar and widely acceptedrisk management as opposed to risk avoidance. Expected value thresholds for decisions such as limiting traffic through FCAs should be established through experience or

24、 customer tolerance to cost.The human remains in the ATM decision loop to take advantage of human judgment. Thus, weather products should be of high information content and high “at a glance value.” It will be difficult to arrive at a complete set of rules for all situations needed to fully automate

25、 ATM functions.Decision support rules and thresholds for weather will be different for different users and operators as well as for different regions of airspace and weather hazard types. Weather hazards can be classified as hard constraints, which are volumes of airspace that all aircraft will avoi

26、d; and soft constraints with varying degrees of softness, which are airspace volumes that are restricted due to aircraft limitations or operational preferences. Automated DST capabilities will be directly integrated with weather information so that candidate solutions to weather-related problems can

27、 be rapidly developed and presented to decision makers for consideration. DSTs will automate the translation of weather to ATM impact.2American Institute of Aeronautics and AstronauticsSurface, terminal, and en route DSTs will include consideration for the effect that weather constraints have on eac

28、h domain. These domains must be seamlessly integrated.In general, NAS users will all share the same picture of the environment coordinated through System-Wide Information Management (SWIM) and, specifically for weather, the included NextGen Net-enabled Weather (NNEW) 4D “Weather Data Cube.” The Weat

29、her Cube provides the single authoritative source for all environmental data. It is in some ways similar to the Aviation Digital Data Service (ADDS) 8.II.Concept of UseA.NextGen Strategic and Tactical PlanningWe now present concepts associated with strategic, system-wide planning coupled with tactic

30、al routing for NextGen Traffic Flow Management (TFM) as specified by NASAs Virtual Airspace Modeling and Simulation (VAMS) project 9.System-Wide Optimization and Planning (SWOP) will continually evaluate user preferred flight plans and flight plan amendments and provide the ability for the system to

31、 optimally accommodate those plans to the extent possible. In NextGen, SWOP performs optimization and planning on a planning horizon of 20 minutes to 6 10 hours. Where accommodation cannot be made, SWOP modifies the plans according to some optimization criteria (e.g., minimum fuel, minimum time, min

32、imum disruption of schedules), consistent with the policy of “Better- Equipped, Better-Served,” and makes periodic adjustments to the NAS Strategic Plan of Operations (SPO). This process is continuous and dynamic throughout the day.Associated with each element of the selected route structures is a “

33、cost” in the sense that a user may incur some penalty (such as higher fuel consumption) for avoiding a hard or soft constraint (such as a forecast of convection or turbulence potential). Users then select a flight plan based on their particular “rules” which can be specified within SWIM or dynamical

34、ly through collaboration.Route planning is performed using 4DTs that include user RequiredNavigation (RNP)Performancelevels,userpreferences (user thresholdsfor hard and soft constraints), and priorities, all distributedthroughSWIM.Routeplanning and ANSP SPOadjustments are facilitated by strategic co

35、ordination and collaboration of the intent of Airline Operations Control,(AOC)fleetmanagementstrategies and individual users with the ANSP national TFM strategy (). This coordination is facilitated by SWIM.Prediction of weather and traffic effects must extendfromrelativelyprecisetactical information

36、 for short-termtimehorizonstoFigure 2. Strategic coordination and collaboration source: Ref. 9.probabilisticstrategicinformation for long-term time horizons. For short-term time horizons, deterministic and/or probabilistic models for weather forecasts and deterministic trajectory predictions (includ

37、ing how pilots avoid hazardous weather cells, turbulence, and icing) provide a means for the ANSP to plan for safe weather avoidance. For longer time horizons, probabilistic decision making uses probabilistic weather forecasts and planned TFM initiatives to address the expected weather constraints.

38、Advanced DSTs manage large quantities of 4D traffic and integrate 4D weather forecast information for both the tactical and strategic look-ahead times.3American Institute of Aeronautics and AstronauticsWhenever possible, weather-impacted areas are treated as areas of reduced permissible traffic load

39、ing (FCAs) rather than as traffic exclusion areas. Probabilistic coupled traffic and weather prediction analyzes the particular weather phenomena that are expected in order to provide estimates of usable airspace capacity; this must take into consideration human factors issues such as workload and c

40、ontroller skill. The directions of predominant traffic flow must also be considered in assessing the weather impacts. Long-term strategic planning is coordinated seamlessly at physical airspace boundaries and temporally as time transitions from strategic planning to tactical planning horizons. SWOP

41、coordinates upstream and downstream constraints to match the needs and constraints of different airspace domains and airports or groups of airports in close proximity (metroplexes or airportals).Continuous evaluation of filed flight plans and ANSP SPO adjustment is performed by sequential optimizati

42、on where each aircraft trajectory is evaluated and adjusted to meet all known traffic and resource constraints, depending on the user preferences. Certainly, as soft constraints turn hard and hard constraints turn soft, the system must compensate earlier by dynamically rerouting aircraft or corridor

43、s to gain the most in terms of benefit and efficiency.Tightly coupled with implementing deterministic trajectory predictions is the use of aircraft intent information as the strategic plan dynamically evolves due to actual environmental conditions. As the look-ahead time horizon shrinks and the oper

44、ation becomes more tactical, NextGen concepts acknowledge that flow corridors and 4DTs will change. As discussed later, aircraft and pilot intent information becomes critical to dynamic and effective adjustment of flows due to changes in the operational environment. Datalink broadcast of intentions

45、for inclusion into the SWIM database is an essential element to the adjustment process as the operation becomes more tactical.B. Weather Impact Interaction GridThe Weather Impact Interaction Grid is a useful structure to assist NextGen planners involved with the integration of weather hazards into A

46、TM planning. The Weather Impact Interaction Grid provides the framework for defining the impact of aircraft class and capabilities against varying weather phenomena, which in turn guides the development of the most efficient risk management strategies.Not all aircraft respond to weather hazards in t

47、he same way. Therefore, the Weather Impact Interaction Grid has two dimensions: Class of Aircraft andWeather Hazard Type.Two classes of aircraft are considered relative to the response to hard and soft constraints:Class 1 aircraft are those that avoid both hard and soft constraints.Class 2 aircraft

48、are those that avoid hard constraints but are still willing to fly through soft constraints.More aircraft classes may be defined to account for response strategies to weather hazard types.Aircraft class is determined by a number of factors and not just type of operation. For example, a passenger jet

49、liner may respond as a Class 1 aircraft under one airlines policy and a Class 2 under another set of rules. General Aviation (GA) aircraft will operate as either Class 1 or 2 depending on user preferences. Factors defining aircraft class include Rules of operation (VFR, IFR, Part 91, Part 121 or 135

50、)Aircraft equipage and performance limitations Airline policiesPersonal pilot preference.As an example, Table 1 defines the constraint type based on whether the aircraft is certified for flight into icing conditions. Class 1 avoids hard and soft constraints; Class 2 avoids hard constraints but can f

51、ly through moderate or less severe icing (although aircraft flight manuals specify a time limit by aircraft type). Severe icing (SIGMET icing in particular) is always a hard constraint.Table 1. Weather Constraint Types for different levels of icing.The concept is illustrated in Figure 3 where we hav

52、e defined three Classes of aircraft and four types of weather events. Example routes (dark blue, light blue, magenta) are shown to illustrate possible ways Class 1, 2, and 3 aircraft, respectively, can transverse the region of weather events of Types 1-4. All Classes of aircraft must avoid the hard

53、(red) constraints, so no viable routes are allowed to pass through such red constraint regions. However, each4American Institute of Aeronautics and AstronauticsSeverityConstraint Type forConstraint Type for Uncertified AircraftCertified AircraftLight IcingHard ConstraintNo ConstraintModerate IcingHa

54、rd ConstraintSoft ConstraintSevere IcingHard ConstraintHard ConstraintClass of aircraft has a different threshold for the soft constraints (shades of grey). Consider four types of weather events. Types 1 through 3 are soft constraints, and Type 4 is a hard constraint. We have already noted that all

55、Classes of aircraft must avoid Type 4; this is indicated with an x symbol in the weather impact interaction grid. The soft constraint of Type 3 (dark grey) must be avoided by Class 3 aircraft, but may be traversed by Class 1 or 2 aircraft (if they benefit from doing so). The soft constraint of Type

56、2 (medium grey) must be avoided by Class 1 and 2 aircraft, but may be traversed by Class 3 aircraft (if there is a benefit in doing so). Also, the soft constraint of Type 1 (light grey) must be avoided by Class 2 and 3 aircraft, but may be traversed by Class 1 aircraft (if there is a benefit in doin

57、g so). Given this Weather Impact Interaction Grid established by the preferences of the pilots and airlines in their filed flight plans, and certain regulatory requirements, the problem is to identify a set of routes crossing the airspace such that the demand is satisfied for all Classes of aircraft

58、 given the constraints imposed in the Weather Impact Interaction Grid.All Classes of aircraft must avoid the hard constraintsFCAWeather Event Type jWeather Impact Interaction GridAs specified in the interaction grid, Class 2 aircraft can freely penetrate type 3 weather eventsFigure 3. Capacity computation for three Classes of aircraft (1, 2, 3) among hard (red) and soft constraints (shades of grey) of multiple types (1, 2, or 3).The Weather Impact Interaction Grid models all known weather hazards as hard and soft constraints. Some considerations for modeling th