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VTOL Procedures

Hover | Hover Translate | Transition to Forward Flight | Transition to Hover | Vertical Landing | Vertical Takeoff

There are six VTOL procedures - Hover, Hover Translate, Transition to Forward Flight, Transition to Hover, Vertical Landing, and Vertical Takeoff.

Hover

A Hover procedure is a procedure in which the aircraft hovers in place for a fixed time, or performs a maneuver relative to the end of the previous procedure. This procedure can only be defined for the "End of previous procedure" site type.

The procedure contains one control point - the "End of previous procedure" point - which is either at the same location as the end of the previous procedure, or at the end of the hovering maneuver, if the aircraft performs one - as indicated in the diagram below.

Field Description
Name Enter a specific name for the procedure, if desired.
Fixed Time / Maneuver Select to have the aircraft hover in place for a fixed time, or to perform a hovering maneuver. If you select Fixed Time, all fields other than the time field will become inactive.
Final Altitude Define the aircraft's altitude at the end of the procedure. Select the AGL (Above Ground Level) or MSL (Mean Sea Level) reference and enter an altitude in the specified units. The altitude is constrained by the lowest ceiling value of the active performance models in the current mission phase.
Final Altitude Rate

Select the altitude rate of the aircraft at the end of the procedure from the drop-down menu:

  • Automatic - the rate during the procedure will be maintained if appropriate for the next procedure’s maneuvers. If the subsequent procedure requires a reversal in the altitude rate, it will be set to zero at the transition between procedures.
  • Always Stop - the altitude rate will be set to zero at the transition between procedures.
Final Heading Select the heading of the aircraft at the end of the procedure. Select Relative or Absolute to define the heading of the aircraft from its previous heading or from north, respectively, at the end of the procedure. If you have selected an Absolute heading, specify a True or Magnetic north reference using the drop-down menu. Select Final Translation Bearing to have the aircraft end the procedure on the same heading as its translation bearing at the end of the procedure.
Final Heading Rate

Select the heading rate of the aircraft at the end of the procedure from the drop-down menu:

  • Automatic - the rate during the procedure will be maintained if appropriate for the next procedure’s maneuvers. If the subsequent procedure requires a reversal in the heading rate, it will be set to zero at the transition between procedures.
  • Always Stop - the heading rate will be set to zero at the transition between procedures.
Align with translation and delay final heading change Select to have the aircraft begin changing its heading at a point in time during the procedure such that it won't achieve the final heading until the procedure's translation is completed.
Mode

Select the translation mode from the drop-down menu:

  • Set Bearing and Range - the aircraft will translate on a specific bearing and range, at a specific translation rate.
  • Come to stop - the aircraft will decrease its translation rate along the bearing and range at which it began the procedure until it comes to a complete stop.
  • Maintain initial translation - the aircraft will continue to translate according to the bearing, range, and translation rate at which it began the procedure.
Bearing Define the bearing of the hovering maneuver from the end of the previous procedure. Specify a True or Magnetic north reference using the drop-down menu.
Range Define the distance of the hovering maneuver from the end of the previous procedure.
Waypoint... Click to select a waypoint to define the bearing and range of the hovering maneuver from the end of the previous procedure.
Translate directly Select to have the aircraft translate directly as defined in the Bearing and Range fields.
Anticipate next translation bearing Select to have the aircraft evaluate the procedure ahead to determine the translation bearing it should have at its end point and use a translation rate that is appropriate for the translation distance of the next procedure.
Smooth Translation

Select the translation rate of the aircraft at the end of the procedure from the drop-down menu:

  • Automatic - the aircraft will use the Enroute procedure methodology to generate the horizontal flight path.
  • Always Stop - the aircraft will translate along a straight line between the start and stop point and will come to a stop at the end.

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Hover Translate

A Hover Translate procedure is a procedure that makes a hovering traverse between two waypoints. The aircraft travels along a route from the end of the previous procedure to the site of the current procedure, taking into account the specific heading at the end of the last procedure and setting the aircraft to a specified heading at the end of the current procedure.

The procedure contains one control point - the procedure site - as indicated in the diagram below.

Field Description
Name Enter a specific name for the procedure, if desired.
Final Altitude Define the aircraft's altitude at the end of the procedure. Select the AGL (Above Ground Level) or MSL (Mean Sea Level) reference and enter an altitude in the specified units. The altitude is constrained by the lowest ceiling value of the active performance models in the current mission phase.
Final Altitude Rate

Select the altitude rate of the aircraft at the end of the procedure from the drop-down menu:

  • Automatic - the rate during the procedure will be maintained if appropriate for the next procedure’s maneuvers. If the subsequent procedure requires a reversal in the altitude rate, it will be set to zero at the transition between procedures.
  • Always Stop - the altitude rate will be set to zero at the transition between procedures.
Final Heading Select the heading of the aircraft at the end of the procedure. Select Relative or Absolute to define the heading of the aircraft from its previous heading or from north, respectively, at the end of the procedure. If you have selected an Absolute heading, specify a True or Magnetic north reference using the drop-down menu. Select Final Translation Bearing to have the aircraft end the procedure on the same heading as its translation bearing at the end of the procedure.
Final Heading Rate

Select the heading rate of the aircraft at the end of the procedure from the drop-down menu:

  • Automatic - the rate during the procedure will be maintained if appropriate for the next procedure’s maneuvers. If the subsequent procedure requires a reversal in the heading rate, it will be set to zero at the transition between procedures.
  • Always Stop - the heading rate will be set to zero at the transition between procedures.
Align with translation and delay final heading change Select to have the aircraft begin changing its heading at a point in time during the procedure such that it won't achieve the final heading until the procedure's translation is completed.
Translate directly Select to have the aircraft translate directly as defined in the Bearing and Range fields.
Anticipate next translation bearing Select to have the aircraft evaluate the procedure ahead to determine the translation bearing it should have at its end point and use a translation rate that is appropriate for the translation distance of the next procedure.
Smooth Translation

Select the translation rate of the aircraft at the end of the procedure from the drop-down menu:

  • Automatic - the aircraft will use the Enroute procedure methodology to generate the horizontal flight path.
  • Always Stop - the aircraft will translate along a straight line between the start and stop point and will come to a stop at the end.

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Transition to Forward Flight

A Transition to Forward Flight procedure brings an aircraft from hover mode to forward flight mode. The procedure contains one control point - the procedure site - as indicated in the diagram below.

The aircraft will execute a translating maneuver if the final conditions of the previous procedure dictate any altitude, heading or translation rate. If there are any rates in heading, altitude or translation entering the procedure, the aircraft will immediately commence (or continue) the translation at the performance model translation rate while rotating its heading and continuing its altitude rate until established on the translation heading, at which point the aircraft will accelerate to its forward flight airspeed.

If this procedure is interrupted, the transition will be incomplete and the aircraft will remain in hover mode.

Field Description
Name Enter a specific name for the procedure, if desired.
Transition Heading Select Relative or Absolute to define the heading of the aircraft from its previous heading or from north, respectively. If you have selected an Absolute heading, specify a True or Magnetic north reference using the drop-down menu.
Flight Path Angle Define the pitch angle of the flight path at the end of the procedure.

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Transition to Hover

A Transition to Hover procedure brings an aircraft from forward flight mode to hover mode. The procedure contains one control point - the procedure site - as indicated in the diagram below.

If this procedure is interrupted, the transition will be incomplete and the aircraft will remain in hover mode.

Field Description
Name Enter a specific name for the procedure, if desired.
Altitude Define the aircraft's altitude at the end of the procedure. Select the AGL (Above Ground Level) or MSL (Mean Sea Level) reference and enter an altitude in the specified units. The altitude is constrained by the lowest ceiling value of the active performance models in the current mission phase.
Heading Define the heading of the aircraft from north; specify a True or Magnetic north reference using the drop-down menu.
Smooth Transition Mode

Select the transition mode of the aircraft at the end of the procedure from the drop-down menu:

  • Full Stop - the aircraft's translation and altitude rates are set to zero at the end of the procedure, regardless of the rates specified by the subsequent procedure.
  • Translation Only - the aircraft's translation rate is set in accordance with the rate at the start of the subsequent procedure; the altitude rate is set to zero at the end of the procedure, regardless of the rate specified by the subsequent procedure.
  • Translation and Altitude - the aircraft's translation and altitude rates are set in accordance with the rates at the start of the subsequent procedure.
Use Max Speed When Computing Turn Radii Select to force the aircraft maintain its cruise speed when turning, even if doing so will result in the aircraft making a turn large enough that it takes longer to complete than it would complete a slower, smaller turn.
Turn Factor The Turn Factor is the maximum amount - expressed as a multiplier - that the turn radius will be increased to minimize the bank angle required to complete the turn. The factor is applied only to turns that are performed enroute to the procedure's first control point. The full circles that correspond (or are tangent) to the start/stop turns at the extended radius may not intersect if the factor is set high enough. This parameter is a limit and may not actually be achieved due to the requirement to generate an appropriate turn sequence. You can adjust the slider or enter the value manually in the box, with the minimum value being 1 and the maximum value being 10.
Flight Path Angle Define the pitch angle of the flight path at the end of the procedure.
Radius Factor The Radius Factor is the maximum amount - expressed as a multiplier - that the radius of a vertical curve will be increased to minimize the flight path angle required to complete it. The full circles that correspond (or are tangent) to the start/stop curves at the extended radius may not intersect if the Radius Factor is set high enough. This parameter is a limit and may not actually be achieved due to the requirement to generate an appropriate curve sequence. You can adjust the slider or enter the value manually in the box, with the minimum value being 1 and the maximum value being 10.

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Vertical Landing

A Vertical Landing procedure brings an aircraft down from the air to a VTOL Point. An aircraft cannot perform a Vertical Landing procedure while in forward flight mode.

The procedure contains two control points - the procedure site and the Hover Point - as indicated in the diagram below. The procedure site is defined as the point at which the aircraft is landing. The Hover Point is placed at an altitude equal to the Altitude above point parameter, directly above the procedure site.

Field Description
Name Enter a specific name for the procedure, if desired.
Altitude above point Define the altitude at which the aircraft begins the procedure. The altitude is constrained by the lowest ceiling value of the active performance models in the current mission phase.
Final Altitude Rate

Select the altitude rate of the aircraft at the end of the procedure from the drop-down menu:

  • Automatic - the rate during the procedure will be maintained if appropriate for the next procedure’s maneuvers. If the subsequent procedure requires a reversal in the altitude rate, it will be set to zero at the transition between procedures.
  • Always Stop - the altitude rate will be set to zero at the transition between procedures.
Altitude offset Define an altitude offset above the ground level of the procedure site, if desired.
Heading Define the heading of the aircraft from north. If you have selected an Absolute heading, specify a True or Magnetic north reference using the drop-down menu.
Align with translation and delay final heading change Select to have the aircraft begin changing its heading at a point in time during the procedure such that it won't achieve the final heading until the procedure's translation is completed.

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Vertical Takeoff

A Vertical Takeoff procedure launches an aircraft from a VTOL Point site directly up into the air.

The procedure contains two control points - the procedure site and the Hover Point - as indicated in the diagram below. The procedure site is defined as the point from which the aircraft is taking off. The Hover Point is placed at an altitude equal to the Altitude above point parameter, directly above the procedure site.

Field Description
Name Enter a specific name for the procedure, if desired.
Altitude above point Define the altitude that the aircraft will achieve at the end of the procedure. The altitude is constrained by the lowest ceiling value of the active performance models in the current mission phase.
Final Altitude Rate

Select the altitude rate of the aircraft at the end of the procedure from the drop-down menu:

  • Automatic - the rate during the procedure will be maintained if appropriate for the next procedure’s maneuvers. If the subsequent procedure requires a reversal in the altitude rate, it will be set to zero at the transition between procedures.
  • Always Stop - the altitude rate will be set to zero at the transition between procedures.
Altitude offset Define an altitude offset above the ground level of the procedure site, if desired.
Heading Define the heading of the aircraft from north. If you have selected an Absolute heading, specify a True or Magnetic north reference using the drop-down menu.

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