Aeronautical Diagram Functions Reference

Related documents

• MVCS index
• SVG Drawing Module Reference
• SVG State Variable Reference
• Aeronautical Utilities Reference
• Wind Reference
• CgEnvelope Reference
• CgPoint Reference

Table of contents

• Introduction
• Importing
• drawEnrtDiagramSvg()
• drawRunwaySvg()
• drawWBSvg()

Introduction

These functions draw the common aeronautical diagrams as SVG drawings using an SvgScene: the runway wind diagram on the departure and destination pages, the fuel and time diagram on the enroute page, and the weight and balance diagram on the weight and balance page.

Each function is designed to be assigned as the value of an svg state variable. The state variable calls the function with the wrapper DOM node of the drawing, and the function renders the diagram into the node by setting its innerHTML. If node is falsy, nothing is drawn. The functions read the current state variable values when called, so the drawing must be re-rendered by assigning the function to the state variable again when its inputs change. For example:

io.dep_runwayDiagram.value = (node) => drawRunwaySvg(node, 'dep');

The diagrams use the dark mode setting (nav_darkMode state variable) to select the text and line colors.

Importing

The diagram functions are available for import from common/aero/export.js.

drawEnrtDiagramSvg()

Syntax

drawEnrtDiagramSvg(node, io)

Draws the enroute fuel and time diagram into node. The diagram has a horizontal fuel bar and a horizontal time bar that both span from zero fuel to the fuel on board (FOB). Between the bars, the fuel on board is divided into colored zones:

• Red: the minimum reserve (without alternate fuel).
• Yellow: the additional fuel needed for the alternate reserve (with alternate fuel), if it is more than the minimum reserve.
• Green: the fuel available for the trip.

If the fuel on board is less than the minimum reserve, the whole bar is red. If the required values are not valid, the bar area is grey.

A solid blue line marks the fuel (and time) to the destination, with boxes showing the fuel to the destination and the estimated time enroute. It is drawn if the fuel remaining at the destination is at least the minimum reserve. A dotted blue line marks the fuel to the alternate airport. It is drawn if the fuel at the alternate is at least the minimum reserve, the alternate is farther than the destination, and the alternate reserve is at least the minimum reserve. The labels at the ends of the bars show the zero values, the fuel on board and the endurance.

Parameters

• node
  The wrapper DOM node of an svg state variable. The function sets its innerHTML to the diagram.
• io
  The object containing the page's state variables (for example, sv). The function uses the following state variables from io:
  • wb_totalFuel, enrt_fuelToDest, enrt_fuelToAlt, enrt_fuelAtDest, enrt_fuelAtAlt, enrt_minReserve, and enrt_reserve
    Unit state variables. The curSv value is used, and the fmtUnit() of wb_totalFuel supplies the fuel units label.
  • enrt_fuelOnBoard_min
    The endurance in minutes.
  • enrt_ete_min
    The estimated time enroute in minutes.

Return value

None.

drawRunwaySvg()

Syntax

drawRunwaySvg(node, pageId)

Draws the takeoff or landing runway wind diagram into node. The diagram contains:

• The runway, drawn vertically with the runway ID at the bottom and a dashed centerline. The runway length is scaled to the diagram height. If the safe runway length is longer than the runway, the diagram is scaled to the safe runway length instead.
• The takeoff or landing roll in transparent green, or in transparent red if it is not less than the runway length. It is shown only if a runway length is specified.
• The safety zone beyond the roll in transparent yellow, or in transparent red if the runway is shorter than the safe runway length.
• The aircraft top-view image (acData.aircraftIcon) at the start of the runway, darkened for contrast.
• The wind vector arrow beside the aircraft, rotated to show the wind direction relative to the runway heading, rounded to 10°. If the wind direction varies between two directions, an arrow is drawn for each direction with a tab. Nothing is drawn for variable (VRB) or calm winds.
• The headwind, tailwind, and crosswind components of the Wind around arrows on the right of the diagram. Gusts are shown as G values. A crosswind that exceeds the aircraft's maximum demonstrated crosswind (acData.maxXwind) is drawn in red. If there is no wind, a headwind of 0 is shown.

Parameters

• node
  The wrapper DOM node of an svg state variable. The function sets its innerHTML to the diagram.

• pageId
  The page ID string of the page to draw the diagram for, such as 'dep', 'dest', or 'alt'. The function uses the following state variables from the page, where ${pageId}_ is the page ID prefix:

  • ${pageId}_runwayId
    The runway ID. If empty, '01' is used.
  • ${pageId}_runwayLength_ft
    The runway length in feet. If empty or 0, 5000 is used and the roll and safety zone are not shown.
  • ${pageId}_roll_ft
    The takeoff or landing roll in feet.
  • ${pageId}_safeRunwayLength_ft
    The safe runway length in feet.
  • ${pageId}_runwayMagDir
    The runway magnetic heading in degrees.

  The wind is created from the page using new Wind(pageId).

Return value

None.

drawWBSvg()

Syntax

drawWBSvg(node, io, bewCg)
drawWBSvg(node, io, bewCg, tkoCg, ldgCg, zfCg)
drawWBSvg(node, io, bewCg, tkoCg, ldgCg, zfCg, cgFn)

Draws the weight and balance diagram into node. The diagram always contains the aircraft's CG envelope (the normal category, or the utility category for utility-only aircraft) with the weight on the vertical axis and the arm on the horizontal axis, a dotted line at the maximum landing weight (if it is lower than the maximum takeoff weight), Fwd and Aft labels, and the basic empty weight (BEW) label.

If the takeoff and zero-fuel CG points are valid, the diagram also contains:

• A blue CG path from the takeoff point to the landing point, and a dotted path from the landing point to the zero-fuel point. If the landing point is not valid, the dotted path is drawn from the takeoff point.
• A dot at the takeoff point and at the landing point, colored green if the point is within the envelope, yellow if it is in a caution zone, and red if it is in a warning zone.
• A vertical bar showing the fuel weight (blue) and payload weight (green) with labels for the fuel volume, fuel weight, and load. The payload bar is outlined in red if the zero-fuel weight exceeds the maximum zero-fuel weight.

The function asserts that the takeoff weight is not less than the landing weight, and that the landing weight is not less than the zero-fuel weight.

Parameters

• node
  The wrapper DOM node of an svg state variable. The function sets its innerHTML to the diagram.
• io
  The object containing the page's state variables (for example, sv). The function uses the wb_payload_lb, wb_totalFuel_gal, and wb_fuelWeight_lb unit state variables from io. The curSv value and fmtUnit() of each are used for the labels.
• bewCg
  A CgPoint for the basic empty weight. The weight sets the bottom of the diagram.
• tkoCg (optional)
  A CgPoint for the takeoff weight and balance. If omitted or not valid, only the envelope is drawn.
• ldgCg (optional)
  A CgPoint for the landing weight and balance. The landing point is not drawn if it is not valid.
• zfCg (optional)
  A CgPoint for the zero-fuel weight and balance. If omitted or not valid, only the envelope is drawn.
• cgFn (optional)
  A function cgFn(fuel) that returns an object with arm and weight properties (like a CgPoint) for the aircraft with fuel gallons of fuel on board. It is used for aircraft whose fuel arm changes as fuel is burned (aircraft with multiple tanks) so the CG path is drawn as a curve. If omitted, the fuel arm is fixed and the CG path is a straight line.

The aircraft data (acData) supplies the envelope (wb.cgEnvelope), the maximum takeoff, landing and zero-fuel weights (wb.maxTkoWeight, wb.maxLdgWeight, and wb.maxZfWeight), and the fuel density (fuel.lbToGal()).

Return value

None.