NavDataExplorer/README.md

References

• https://www.faa.gov/sites/faa.gov/files/regulations_policies/handbooks_manuals/aviation/instrument_procedures_handbook/FAA-H-8083-16B_Chapter_6.pdf
• https://developers.navigraph.com/docs/navigation-data/dfd-data-format#procedure-leg-data-fields-minimum-requirements

Terminators

Arc to Fix (AF)

Example

LGAV BIBE1K SID (Cycle 2507, ID 10653)

Minimum Required Fields

• WptID: FixIdentifier
• TurnDir: TurnDirection
• NavID: RecommendedNavaid
• NavBear: Theta (fix radial)
• NavDist: RHO
• Course: MagCourse (boundary radial)

Instructions

• From preceding fix, fly a smooth arc to the fix identified by (WptID, WptLat, WptLon) or (NavID, NavLat, NavLon, NavDist, NavBear).
• Arc radius shall be NavDist.
• Arc center shall be navaid identified by NavID, NavLat, NavLon.
• Course shall be the boundary radial on which the arc begins, measured from the navaid identified by (NavID, NavLat, NavLon, NavDist, NavBear).
• Arc and turn shall be flown in direction specified by TurnDir.

Units

• NavBear and Course are in degrees magnetic.
• NavDist is in nmi. NavDist is geodesic (great-circle).

Notes

While similar to an RF, the center point is coded differently.

Course to Altitude (CA)

Example

LGAV BIBE1L SID (Cycle 2507, ID 10654)

Minimum Required Fields

• Course: MagCourse
• Alt: Alt1+ (at or above)

Instructions

• From preceding fix, fly along Course until reaching Alt.
• If preceding fix was overfly, offset outbound Course to end of turn (tangent).
• Earliest leg terminations is at point of tangent.

Units

• Course is in degrees magnetic.
• Alt is in ft, but doubles as an FMS constraint.

Notes

The leg terminates upon reaching Alt. This intercept point then becomes the origin fix of the succeeding leg. This new origin is an implicit overfly.

Course to DME Distance (CD)

Example

LGAV BIBE2F SID (Cycle 2507, ID 10657)

Minimum Required Fields

• NavID: RecommendedNavaid
• Course: MagCourse
• Distance: RouteDISTANCEHoldingTime (DME distance)

Instructions

• From preceding fix, fly along Course until reaching Distance from the navaid identified by NavID.
• If preceding fix was overfly, offset outbound Course to end of turn (tangent).
• Earliest leg terminations is at point of tangent.

Units

• Course is in degrees magnetic.
• Distance is in nmi. Distance is slant not geodesic.

Notes

The leg terminates upon reaching Distance. This intercept point then becomes the origin fix of the succeeding leg. This new origin is an implicit overfly.

Course to Fix (CF)

Example

LGAV BIBE2F SID (Cycle 2507, ID 10657)

Minimum Required Fields

• WptID: FixIdentifier
• NavID: RecommendedNavaid
• NavBear: Theta
• NavDist: RHO
• Course: MagCourse
• Distance: RouteDISTANCEHoldingTime (Path length)

Instructions

• From preceding fix, fly Course to the fix identified by (WptID, WptLat, WptLon) or (NavID, NavLat, NavLon, NavDist, NavBear).
• If preceding fix was overfly, continue turn until intercept Course, then continue on Course.

Units

• NavBear and Course are in degrees magnetic.
• NavDist and Distance are in nmi. NavDist and Distance are geodesic.

Notes

While this might feel like a TF, it isn't. A TF does not specify an exact course to be flown, relying on the computers to figure out the great-circle between the two fixes.

My guess is, that a CF results in the turn from the preceding fix to be shifted so as to ensure the outbound course to the specified fix is equal to the coded course.

Additionally, if a TurnDir is specified, if a large turn is required to fly Course, the turn shall be TurnDir. This is a major difference to TF, these never produce such turns.

Course to Intercept (CI)

Example

LGAV BIBE1L SID (Cycle 2507, ID 10654)

Minimum Required Fields

• Course: MagCourse

Instructions

• From preceding fix, fly Course until interception of course of the succeeding leg.

Units

• Course is in degrees magnetic.

Notes

This needs to look into the succeeding leg in order to calculate the intercept point. This intercept point then becomes the origin fix of the succeeding leg. This new origin can never be an overfly due to the intercept nature.

Course to Radial Termination (CR)

Example

LGAV KOR1D SID (Cycle 2507, ID 10679)

Minimum Required Fields

• NavID: RecommendedNavaid
• NavBear: Theta
• Course: MagCourse

Instructions

• From preceding fix, fly Course until interception of NavBear radial from the navaid identified by (NavID, NavLat, NavLon).

Units

• NavBear and Course are in degrees magnetic.

Notes

The leg terminates at the intercept point. This intercept point then becomes the origin fix of the succeeding leg.

Direct to Fix (DF)

Example

LGAV KOR1D SID (Cycle 2507, ID 10679)

Minimum Required Fields

• WptID: FixIdentifier
• IsFlyOver: Flyover

Instructions

• From present position, fly direct to fix identified by WptID

Units

• IsFlyOver: Boolean indicating if fix is a mandatory fly over.

Track from Fix to Altitude (FA)

Example

LGAV BIBE2F SID (Cycle 2507, ID 10657)

Minimum Required Fields

• WptID: FixIdentifier
• NavID: RecommendedNavaid
• NavBear: Theta
• NavDist: RHO
• Course: MagCourse
• Alt: Alt1+ (at or above)

Instructions

• From the fix identified by (WptID, WptLat, WptLon) or (NavID, NavLat, NavLon, NavDist, NavBear), fly Course until reaching Alt.
• If preceding fix was overfly, continue turn until intercept Course, then continue on Course.
• Earliest leg terminations is at point of intercept.

Units

• NavBear and Course are in degrees magnetic.
• NavDist is in nmi. NavDist is geodesic.
• Alt is in ft, but doubles as an FMS constraint.

Notes

The leg terminates upon reaching Alt. This intercept point then becomes the origin fix of the succeeding leg. This new origin is an implicit overfly.

Track from Fix for Distance (FC)

Example

LIED CAR6F SID (Cycle 2507, ID 11798)

Minimum Required Fields

• WptID: FixIdentifier
• IsFlyOver: FlyOver
• NavID: RecommendedNavaid
• NavBear: Theta
• NavDist: RHO
• Course: MagCourse
• Distance: RouteDISTANCEHoldingTime (Path length)

Instructions

• From the fix identified by (WptID, WptLat, WptLon) or (NavID, NavLat, NavLon, NavDist, NavBear), fly Course until reaching Distance.
• If preceding fix was overfly, continue turn until intercept Course, then continue on Course.
• Earliest leg terminations is at point of intercept.

Units

• NavBear and Course are in degrees magnetic.
• NavDist and Distance are in nmi. NavDist and Distance are geodesic.
• IsFlyOver: Boolean indicating if fix is a mandatory fly over.

Notes

The leg terminates upon reaching Distance. This intercept point then becomes the origin fix of the succeeding leg.

Track from Fix to DME Distance (FD)

Example

LGAV BIBE2T SID (Cycle 2507, ID 10659)

Minimum Required Fields

• WptID: FixIdentifier
• NavID: RecommendedNavaid
• NavBear: Theta
• NavDist: RHO
• Course: MagCourse
• Distance: RouteDISTANCEHoldingTime (DME distance)

Instructions

• From the fix identified by (WptID, WptLat, WptLon) or (NavID, NavLat, NavLon, NavDist, NavBear), fly Course until reaching Distance from navaid identified by NavID.
• If preceding fix was overfly, continue turn until intercept Course, then continue on Course.
• Earliest leg terminations is at point of intercept.

Units

• NavBear and Course are in degrees magnetic.
• NavDist and Distance are in nmi. NavDist is geodesic, Distance is slant.

Notes

The leg terminates upon reaching Distance. This intercept point then becomes the origin fix of the succeeding leg. This new origin is an implicit overfly.

Track from Fix to Manual Termination (FM)

Example

LFPV PB2V SID (Cycle 2507, ID 10395)

Minimum Required Fields

• WptID: FixIdentifier
• NavID: RecommendedNavaid
• NavBear: Theta
• NavDist: RHO
• Course: MagCourse

Instructions

• From the fix identified by (WptID, WptLat, WptLon) or (NavID, NavLat, NavLon, NavDist, NavBear), fly Course indefinitely.

Units

• NavBear and Course are in degrees magnetic.
• NavDist is in nmi. NavDist is geodesic.

Holding mandatory (HA)

Example

LOWG GRZ4X SID (Cycle 2507, ID 12765)

Minimum Required Fields

• WptID: FixIdentifier
• TurnDir: TurnDirection
• Course: MagCourse
• Distance: RouteTIMEDistanceHoldingTime
• Alt: Alt1+ (at or above)

Instructions

• At fix identified by (WptID, WptLat, WptLon), enter TurnDir direction holding pattern.
• Course shall be the inbound course of the holding.
• Distance shall be the holding leg distance or time
• Alt shall be the altitude at which the holding is exited

Units

• Course is in degrees magnetic.
• Distance is in nmi or min. Distance is geodesic if in nmi.
• Alt is in ft, but doubles as an FMS constraint.

Notes

As per the docs, there should be a field indicating whether Distance is distance or time. I have not found the field or anything that alludes to such. Conversely, as per the FAA, the altitude should be the exit point of the leg. This goes against the textual description of the example.

My guess is that the holding is at all times executed at leat once, even if the entry to it is also the exit altitude. As for the missing time/distance decider field, assume it to be distance at all times.

Holding in lieu of Procedure Turn (HF)

Example

FAWB VDM29 APP (Cycle 2507, ID 67794)

Minimum Required Fields

• WptID: FixIdentifier
• TurnDir: TurnDirection
• Course: MagCourse
• Distance: RouteTIMEDistanceHoldingTime

Instructions

• At fix identified by (WptID, WptLat, WptLon), enter TurnDir direction holding pattern.
• Course shall be the inbound course of the holding.
• Distance shall be the holding leg distance or time
• Holding shall be exited after exactly one turn

Units

• Course is in degrees magnetic.
• Distance is in nmi or min. Distance is geodesic if in nmi.

Notes

As per the docs, there should be a field indicating whether Distance is distance or time. I have not found the field or anything that alludes to such.

My guess is that Distance always is a distance. This would match with the example.

The Leg terminates after the hold is exited ath the hold entry fix.

Holding mandatory (HM)

Example

FAWB VDM29 APP (Cycle 2507, ID 67794), Missed approach procedure

Minimum Required Fields

• WptID: FixIdentifier
• TurnDir: TurnDirection
• Course: MagCourse
• Distance: RouteTIMEDistanceHoldingTime

Instructions

• At fix identified by (WptID, WptLat, WptLon), enter TurnDir direction holding pattern.
• Course shall be the inbound course of the holding.
• Distance shall be the holding leg distance or time
• Holding shall be indefinite

Units

• Course is in degrees magnetic.
• Distance is in nmi or min. Distance is geodesic if in nmi.

Notes

As per the docs, there should be a field indicating whether Distance is distance or time. I have not found the field or anything that alludes to such.

My guess as for the missing time/distance decider field, assume it to be distance at all times.

Initial Fix (IF)

Example

FAWB VDM29 APP (Cycle 2507, ID 67794), Missed approach procedure

Minimum Required Fields

• WptID: FixIdentifier

Instructions

• Start of a STAR or APP

Notes

Nothing to be done except parse restrictions. Servers as the entry point of a STAR/APP procedure.

Procedure Turn (PI)

Example

FAUP VDM35 APP (Cycle 2507, ID 67790)

Minimum Required Fields

• WptID: FixIdentifier
• TurnDir: TurnDirection
• NavID: RecommendedNavaid
• NavBear: Theta
• NavDist: RHO
• Course: MagCourse
• Distance: RouteTimeDISTANCEHoldingTime (excursion distance from fix)
• Alt: Alt1

Instructions

• From the fix identified by (WptID, WptLat, WptLon) or (NavID, NavLat, NavLon, NavDist, NavBear), fly Course for Distance.
• Turn TurnDir until aligned with succeeding leg course.
• Alt shall be the altitude during the procedure.

Units

• NavBearand Course are in degrees magnetic.
• NavDist and Distance are in nmi. NavDist and Distance are geodesic.
• Alt is in ft, but doubles as an FMS constraint.

Notes

This needs to look into the succeeding leg in order to calculate the intercept point. This intercept point then becomes the origin fix of the succeeding leg.

Radius to Fix (RF)

Example

LFRN GODA5R SID (cycle 2507, ID 10485)

Minimum Required Fields

• WptID: FixIdentifier
• TurnDir: TurnDirection
• NavBear: Theta (inbound tangential track)
• Course: MagCourse
• Distance: RouteTimeDISTANCEHoldingTime (along track distance)
• CenterID: ArcCenter

Instructions

• From preceding fix, fly a smooth arc to the fix identified by (WptID, WptLat, WptLon).
• Arc center shall be navaid identified by CenterID, CenterLat, CenterLon.
• Arc and turn shall be flown in direction specified by TurnDir.
• Distance shall be the track miles along the curved path

Units

• NavBear and Course are in degrees magnetic.
• Distance is in nmi. Distance is geodesic (great-circle).

Notes

While similar to an AF, the center point is coded differently. No radius is specified, but can be inferred based on center point, both endpoints and arc length

Example has NavBear set to null, significance of the inbound tangential track is unknown. Same for the Course, which is set, but lacks any documentation.

Track to Fix (TF)

Example

LFRN GODA5R SID (cycle 2507, ID 10485)

Minimum Required Fields

• WptID: FixIdentifier
• IsFlyOver: Overfly

Instructions

• From the preceding waypoint, fly direct to the waypoint identified by (WptID, WptLat, WptLon).

Units

• IsFlyOver: Boolean indicating if fix is a mandatory fly over.

Heading to Altitude (VA)

Example

LFRK LGL4X SID (Cycle 2507, ID 10475)

Minimum Required Fields

• Course: MagCourse (Heading)
• Alt: Alt1+ (at or above)

Instructions

• From preceding fix, fly heading specified in Course until reaching Alt.
• No wind corrections shall be applied

Units

• Course is in degrees magnetic.
• Alt is in ft, but doubles as an FMS constraint.

Notes

The leg terminates upon reaching Alt. This intercept point then becomes the origin fix of the succeeding leg. This new origin is an implicit overfly.

Heading to DME Distance (VD)

Example

LFRK NEVI4Y SID (Cycle 2507, ID 10482)

Minimum Required Fields

• NavID: RecommendedNavaid
• Course: MagCourse (Heading)
• Distance: RouteTimeDISTANCEHoldingTime (DME distance)

Instructions

• From preceding fix, fly heading specified in Course until reaching Distance from the navaid identified by (NavID, NavLat, NavLon).
• No wind corrections shall be applied

Units

• Course is in degrees magnetic.
• Distance is in nmi. Distance is slant not geodesic.

Notes

The leg terminates upon reaching Distance. This intercept point then becomes the origin fix of the succeeding leg. This new origin is an implicit overfly.

Heading to Intercept (VI)

Example

LFRK LUSI4Y SID (Cycle 2507, ID 10480)

Minimum Required Fields

• Course: MagCourse

Instructions

• From preceding fix, fly heading specified in Course until interception of course of the succeeding leg.
• No wind corrections shall be applied

Units

• Course is in degrees magnetic.

Notes

This needs to look into the succeeding leg in order to calculate the intercept point. This intercept point then becomes the origin fix of the succeeding leg. This new origin can never be an overfly due to the intercept nature.

Heading to Manual Termination (VM)

Example

LFPV PB2P SID (Cycle 2507, ID 10394)

Minimum Required Fields

• Course: MagCourse (Heading)

Instructions

• From preceding fix, fly heading specified in Course indefinitely
• No wind corrections shall be applied

Units

• Course is in degrees magnetic.

Heading to Radial (VR)

Example

LIMC MMP8G SID (Cycle 2507, ID 11909)

Minimum Required Fields

• NavID: RecommendedNavaid
• NavBear: Theta
• Course: MagCourse

Instructions

• From preceding fix, fly heading specified in Course until interception of NavBear radial from the navaid identified by NavID.

Units

• NavBear and Course are in degrees magnetic.

Notes

The leg terminates at the intercept point. This intercept point then becomes the origin fix of the succeeding leg.