FlightGear is a free flight simulator project. It is being developed through the gracious contributions of source code and spare time by many talented people from around the globe. Among the many goals of this project are the quest to minimize short cuts and "do things right", the quest to learn and advance knowledge, and the quest to have better toys to play with.
The idea for Flight Gear was born out of a dissatisfaction with current commercial PC flight simulators. A big problem with these simulators is their proprietariness and lack of extensibility. There are so many people across the world with great ideas for enhancing the currently available simulators who have the ability to write code, and who have a desire to learn and contribute.
Many people involved in education and research could use a spiffy flight simulator frame work on which to build their own projects; however, commercial simulators do not lend themselves to modification and enhancement. The Flight Gear project is striving to fill these gaps and offer you a proper experience.
There are a wide range of people interested and participating in this project. This is truly a global effort with contributors from just about every continent. Interests range from building a realistic home simulator out old airplane parts, to university research and instructional use, to simply having a viable alternative to commercial PC simulators.
Flight Gear and its source code have intentionally been kept open, available, and free. In doing so, we are able to take advantage of the efforts of tremendously talented people from around the world. Contrast this with the traditional approach of commercial software vendors, who are limited by the collective ability of the people they can hire and pay. Our approach brings its own unique challenges and difficulties, but we are confident (and other similarly structured projects have demonstrated) that in the long run we can outclass the commercial "competition."
Here are some key features of "FlightGear":
High degree of Freedom
· FlightGear is an open-source project. This means as long as you abide by the terms of the GPL license you may freely download and copy FlightGear. Anyone can have easy and open access to the latest development source code. Being an open-source project, we have made our file formats open and easily accessible. We support standard 3d model formats and much of the simulator configuration is controlled through xml based ascii files. Writing 3rd party extensions for FlightGear (or even directly modifying the FlightGear source code) is straightforward and doesn't require a large amount of reverse engineering. This makes FlightGear an attractive option for use in private, commercial, research, or hobby projects.
· FlightGear is known to run on Windows, Linux, Mac OS-X, FreeBSD, Solaris, and IRIX platforms allowing the user run on their platform of preference.
Flight Dynamics Models
· With FlightGear it is possible to choose between three primary Flight Dynamics Models. It is possible to add new dynamics models or even interface to external "proprietary" flight dynamics models:
· JSBSim: JSBSim is a generic, 6DoF flight dynamics model for simulating the motion of flight vehicles. It is written in C++. JSBSim can be run in a standalone mode for batch runs, or it can be the driver for a larger simulation program that includes a visuals subsystem (such as FlightGear.) In both cases, aircraft are modeled in an XML configuration file, where the mass properties, aerodynamic and flight control properties are all defined.
· YASim: This FDM is an integrated part of FlightGear and uses a different approach than JSBSim by simulating the effect of the airflow on the different parts of an aircraft. The advantage of this approach is that it is possible to perform the simulation based on geometry and mass information combined with more commonly available performance numbers for an aircraft. This allows for quickly constructing a plausibly behaving aircraft that matches published performance numbers without requiring all the traditional aerodynamic test data.
· UIUC: This FDM is based on LaRCsim originally written by the NASA. UIUC extends the code by allowing aircraft configuration files instead and by adding code for simulation of aircraft under icing conditions.
· UIUC (like JSBSim) uses lookup tables to retrieve the component aerodynamic force and moment coefficients for an aircraft... and then uses these coefficients to calculate the sum of the forces and moments acting on the aircraft.
Extensive and Accurate World Scenery Data Base
· Over 20,000 real world airports included in the full scenery set.
· Correct runway markings and placement, correct runway and approach lighting.
· Taxiways available for many larger airports (even including the green center line lights when appropriate.)
· Sloping runways (runways change elevation like they usually do in real life.)
· Directional airport lighting that smoothly changes intensity as your relative view direction changes.
· World scenery fits on 3 DVD's. (I'm not sure that's a feature or a problem!) But it means we have pretty detailed coverage of the entire world.
· Accurate terrain worldwide, based on the most recently released SRTM terrain data.) 3 arc second resolution (about 90m post spacing) for North and South America, Europe, Asia, Africa, and Australia.
· Scenery includes all vmap0 lakes, rivers, roads, railroads, cities, towns, land cover, etc.
· Nice scenery night lighting with ground lighting concentrated in urban areas (based on real maps) and headlights visible on major highways. This allows for realistic night VFR flying with the ability to spot towns and cities and follow roads.
· Scenery tiles are paged (loaded/unloaded) in a separate thread to minimize the frame rate hit when you need to load new areas.
· Accurate and Detailed Sky Model
· FlightGear implements extremely accurate time of day modeling with correctly placed sun, moon, stars, and planets for the specified time and date. FlightGear can track the current computer clock time in order to correctly place the sun, moon, stars, etc. in their current and proper place relative to the earth. If it's dawn in Sydney right now, it's dawn in the sim right now when you locate yourself in virtual Sydney. The sun, moon, stars, and planets all follow their correct courses through the sky. This modeling also correctly takes into account seasonal effects so you have 24 hour days north of the arctic circle in the summer, etc. We also illuminate the correctly placed moon with the correctly placed sun to get the correct phase of the moon for the current time/date, just like in real life.
· Flexible and Open Aircraft Modeling System
· FlightGear has the ability to model a wide variety of aircraft. Currently you can fly the 1903 Wright Flyer, strange flapping wing "ornithopters", a 747 and A320, various military jets, and several light singles. FlightGear has the ability to model those aircraft and just about everything in between.
· FlightGear has extremely smooth and fluid instrument animation that updates at the same rate as your out-the-window view updates (i.e. as fast as your computer can crank, and not artificially limited and chunky like in some sims.)
· FlightGear has the infrastructure to allow aircraft designers to build fully animated, fully operational, fully interactive 3d cockpits (which even update and display correctly from external chase plane views.)
· FlightGear realistically models real world instrument behavior. Instruments that lag in real life, lag correctly in FlightGear, gyro drift is modeled correctly, the magnetic compass is subject to aircraft body forces -- all those things that make real world flying a challenge.
· FlightGear also accurately models many instrument and system failures. If the vacuum system fails, the HSI gyros spin down slowly with a corresponding degradation in response as well as a slowly increasing bias/error.
Moderate Hardware Requirements
· The intention of FlightGear is to look nice, but not at the expense of other aspects of a realistic simulator. Our focus is not on competing in the "game" market and not on the ultra-flashy graphic tricks.
· The result is a simulator with moderate hardware requirements to run at smooth frame rates. You can be reasonably happy on a $500-1000 (USD) machine (possibly even less if you are careful) and don't necessarily need $3000 (USD) worth of new hardware like you do with the many of the newest games.
· That said, the more hardware you throw at FlightGear, the better it looks and runs, so don't feel like you have to chuck your expensive new hardware if you just purchased it.
Internal Properties EXPOSED!
· FlightGear allows users and aircraft designers access to a very large number of internal state variables via numerous internal and external access mechanisms. These state variables are organized into a convenient hierarchal "property" tree.
· Using the properties tree it is possible to monitor just about any internal state variable in FlightGear. It's possible to remotely control FlightGear from an external script. You can create model animations, sound effects, instrument animations and network protocols for about any situation imaginable just by editing a small number of human readable configuration files. This is a powerful system that makes FlightGear immensely flexible, configurable, and adaptable.
· A number of networking options allow FlightGear to communicate with other instances of FlightGear, GPS receivers, external flight dynamics modules, external autopilot or control modules, as well as other software such as the Open Glass Cockpit project and the Atlas mapping utility.
· A generic input/output option allows for a user defined output protocol to a file, serial port or network client.
· A multi player protocol is available for using FlightGear on a local network in a multi aircraft environment, for example to practice formation flight or for tower simulation purposes.
· The powerful network options make it possible to synchronize several instances of FlightGear allowing for a multi-display, or even a cave environment. If all instances are running at the same frame rate consistently, it is possible to get extremely good and tight synchronization between displays.
What's New in This Release: [ read full changelog ]
· Architecture improvements introduced in this release mean that subsystems such as the traffic manager may be stopped and re-started dynamically within a simulation session. In future releases it is expected that more and more subsystems will support this function, making FG more scalable, and more flexible for distributed multi-machine simulators.
Atmospheric Light Scattering:
· F-14b over the alps at dusk
· Atmospheric light scattering is an alternative rendering framework, using exceptionally realistic environment-dependent fog and light computations for clouds and terrain. The simulation includes the following lighting models.
· Rayleigh, Mie and diffuse multiple scattering of light in the atmosphere, on haze and on clouds, for more realistic atmospheric lighting.
· Volumetric ground fog simulation, so fog varies in thickness both horizontally and vertically.
· Realistic ambient and diffuse light curves for sunset and sunrise conditions, making evening flights more realistic.
· Improved night VFR flying due to a moonlight illumination model.
· Together with Advanced Weather, it functions as an integrated environment simulation in which the individual elements mutually influence each other.
· Clouds and winds are influenced by the distribution of terrain elevation
· Prevailing winds, terrain slopes and stability of the lower atmosphere determine the shape of visible clouds
· Cloud layers and haze influence color and intensity of light reflections
· Winds influence wave patterns on water
· Light at sunrise and sunset is position and altitude dependent, allowing for phenomena such as Alpenglow or brightly illuminated high-altitude clouds while the ground is dark
· For more powerful graphics cards, the framework includes procedural terrain texturing, including features such as the following.
· Non-tiling slope dependent terrain texturing, so scenery looks more featured but with fewer tiling artefacts.
· High resolution close-up texturing effects with up to 10 cm detail resolution and dynamically added bumpmap for low-level flight and better depth perception
· Environmental effects such as terrain wetness (including puddles), dustiness, mossiness, and snow cover. All adjustable by the user and respecting the terrain slope where appropriate.
Improved performance, reduced memory occupancy:
· Startup time and memory occupancy has been reduced by the implementation of a cache of navigation data. Further memory occupancy reductions have been made by improved random buildings. Frame-rates have been improved when using 3D clouds, particularly in overcast conditions.
· Joystick Configuration GUI
Improving FlightGear's usability has been a focus for a number of developers for this release. Changes include:
· A new tool allowing joystick configuration in-sim, making it easier for new users to configure their joysticks as they wish and get flying!
· The Nasal Console has been improved to support copy/paste, making Nasal script development easier.
· The About dialog now includes additional system information, and the ability to copy information to the clipboard, making remote diagnosis of users problems faster and more straightforward.
· The Select Airport option now displays an overhead view of the selected airport, allowing users to preview their new location, and making it easier to choose the correct runway or parking position.
· In-sim checklists have been introduced for a number of aircraft.
· An in-sim documentation browser is included, so users can more easily browse all the documentation available in the base package.
· The weather configuration UIs have been combined and rationalized into a single weather UI, making it easier to select a nice VFR day, or a difficult CATIII approach.
· Flight path can now be displayed on the in-sim map.
· Instant replay may now be saved as a flight recorder, edited externally to add a commentary, and then replayed as a tutorial, with the user able to take control at any point.
· Multiplayer setup dialog now includes a dynamically generated list of active MP servers, making it even easier to take part in FlightGear's worldwide multi-player environment.
· FlightGear continued to benefit from contributions from across the globe.
· The FlightGear Manual is now included in both English and French.
· System messages on startup are available in eight languages, just like the in-sim menu.
Flight Planning and Route Manager:
· Route Manager now has better support for Navigraph procedures.
· Auto-generated SIDs and STARs are available for airports where real procedure data is not available. This generates plausible straight in approach and terminal waypoints based on the route course.
· The "flightplan" Nasal extension function has been improved, making it possible to retrieve a hash representation of the flight plan stored in the route manager. It is now possible to directly show a SVG image for each waypoint and connect them using OpenVG paths.
· Airport Selection dialog, using Canvas to render the airport diagram
Canvas improvements in this release include:
· Lazy updating/rendering to improve performance in situations where a texture doesn't need to be redrawn
· Creating GUI windows, including popup menus or menubars
· Native copy/paste via 2 new Nasal extension functions
· Nested canvases, where a canvas may contain images created by another canvas texture
· Window stacking
· raster images (vector images were already supported)
· Improved event handling GUI events using osgGA
· A new DOM-based event handling system
· Rembrandt old film style
The Rembrandt renderer has been extended with a number of post-processing filters:
· Night vision including amplification grain and restrained field of view
Cinema effect including:
· Color shift, with Sepia as default value
· Radial distortion (barrel and pincushion distortion, with scale compensation)
· Lateral chromatic aberration (purple fringing)
· Film wear simulation
· Additional aircraft have been updated to make use of Rembrandt effects.
· AI aircraft take-offs and landings are now more realistic.
· AI tankers can now be found using the HUD target marker.
Building on the work in 2.8, the following areas now have region-specific texture-sets for more realistic terrain:
· Western Europe
· Tropical South America
Highlighted new and improved aircraft:
· The Boeing 777 has improved cockpit, PFD and NavDisplay.
· The Dassault Mirage 2000-5 has various instrumentation, HUD and stores added.
· The Douglas A-4F Skyhawk has an improved FDM and cockpit, including terrain-clearance radar and navigational computer.
· The Hawker Hurricane has improved FDM and cockpit.
· The Mudry Cap 10B, a classic French two-seat training aerobatic aircraft has been added by the PAF team.
· Additional joysticks and rudder pedals are supported out-of-the-box.
· An interactive aircraft download page allows users to filter aircraft based on their level of completeness and accuracy, making it easier to discover the true gems of our extensive hangar.