Aircraft rating system

From FlightGear wiki
Revision as of 15:46, 25 May 2011 by Stuart (Talk | contribs)

Jump to: navigation, search

With hundreds of aircraft available for FG, it is very difficult to find the true gems. The rating system below attempts to solve this by providing a quick objective way to rate aircraft. This was discussed in some detail on the -dev mailing list in December 2010.

The rating system scores an aircraft (0-5) in 4 individual criteria - FDM, Systems, Cockpit and External Model.

These ratings can then be encoded in the aircraft -set.xml file from where they can be picked up by launchers, web pages etc.

The sum of the scores in the 4 criteria provides an overall score from 0 to 20, which can be mapped to a textual overall aircraft status.

Flight Dynamics Model

  • 0: None, or using FDM from other aircraft
  • 1: JSBSim Aeromatic or YASim geometric model used without tuning. Flaps modeled.
  • 2: FDM tuned for cruise configuration.
  • 3: FDM tuned for rate of climb and cruise PoH performance numbers
  • 4: FDM matches PoH in 90% of configurations
  • 5: FDM matches PoH and most known test data.


  • 0: No controllable systems: engine is always on, generic radio,
  • 1: Generic engine start/stop (}}s), correct size/number of fuel tanks, generic (untuned) autopilot, working flaps/gear
  • 2: Working electrical system, fuel feed cockpit controls, stable autopilot
  • 3: Accurate startup procedure, tuned autopilot with cockpit controls matching real aircraft systems, generic failure modelling (Vne, +ve/-ve G, gear limits)
  • 4: Primary aircraft-specific systems modelled (aero-tow, radar, GPWS). User able to follow normal PoH checklists (e.g. startup, shutdown) in entirety
  • 5: Some aircraft-specific failure modes implemented (e.g. flame-out, inverted engine limitations). Some emergency procedures implemented (RAT, emergency gear release), able to follow some emergency PoH checklists in entirety.


  • 0: No cockpit
  • 1: 2D panel, no cockpit.
  • 2: 2D panel in 3D cockpit, or incomplete 3D panel
  • 3: 3D panel and cockpit
  • 4: 3D panel and accurately modelled 3D cockpit, plain texturing. Hotspots for majority of controls.
  • 5: 3D panel and accurately modelled 3D cockpit with photo-realistic texturing.

External Model

  • 0: None
  • 1: Simple 3D model, no animations
  • 2: 3D model with animated control surfaces (elevator, aileron, rudder, flaps)
  • 3: 3D model with animated control surfaces, gear detailing (retraction), prop
  • 4: 3D model with animated control surfaces, gear, prop, livery support.
  • 5: 3D model with animated control surfaces, gear, prop, livery support, Ambient Occlusion effect.

Overall Status

Sum the ratings of the 4 criteria, to produce an overall score from 0 to 20.

This maps to overall status as follows:

  • 18 or higher : advanced production (minimum 4 in each rating)
  • 16 to 17 : production (minimum 4 in each rating)
  • 12 to 15 : early production (minimum 3 in each rating)
  • 9 to 11 : beta
  • 8 or lower : alpha

Encoding the rating

The ratings can be encoded in the -set.xml file for the aircraft, under <sim> as follows.

<status>early production</status>
 <FDM type="int">5</FDM>
 <systems type="int">4</systems>
 <cockpit type="int">3</cockpit>
 <model type="int">3</model>