From: mechalas@gn.ecn.purdue.edu (John Mechalas)
Newsgroups: rec.aviation.simulators,comp.sys.ibm.pc.games.flight-sim,rec.aviation.answers,rec.answers,news.answers
Subject: rec.aviation.simulators Frequently Asked Questions
Summary: This posting contains frequently asked questions
         for the rec.aviation.simulators newsgroup, and should
         be read by anyone who wishes to post to the group.
Followup-To: poster
Reply-To: mechalas@gn.ecn.purdue.edu
Approved: geoff@peck.com, news-answers-request@mit.edu
Organization: Purdue University Engineering Computer Network

Archive-name: aviation/flight-simulators
Last changed: 12/02/93



                          rec.aviation.simulators
                        FREQUENTLY ASKED QUESTIONS

This FAQ is maintained by mechalas@gn.ecn.purdue.edu (John Mechalas) and
is posted twice a month.  Any comments, suggestions, additions or
corrections are welcome, so feel free to mail me with your ideas.
Those of you on Compuserve may also contact me at 71673,3041.

Similar to the FAQ on rec.aviation, there are |'s (pipes) at the beginning
of each line that contains new information.  This way those of you with
'grep'-like utilities can immediately search this file for the new stuff.

Our "unofficial motto" (smiley-captioned for the humor-impaired):

      "Any product (flight/computer oriented) that considers Angle
      of Attack in an at least semi-realistic way is a sim, any other
      a game."  :)
                  -- Gary Cooper (not the dead one)


Thanks to:  Glenn Wallace, Hayden Nanton, G. David Frye, Robert Dorsett,
            Mark Strawcutter, Brooke Anderson, Jeff Beadles, Joel Murray,
            Linda McGarry, Dan Sharpes, Bruce Jackson, Mary Shafer, Rob
            Jones, Michael Jones, Stefan Frick, Gary Cooper, Jim Knutson,
            Brian, Paulo Ney de Souza, Tim Tessin, Scott Chan, and Alan
            Epstein for their major contributions.

Also thanks to the countless others who are providing me with constant 
feedback and other helpful hints.



 Abbreviations you may see used on this newsgroup:

  AAF or A&AF   Mallard's "Aircraft and Adventure Factory" for MS FS4
  ACM           "Air Combat Maneuvers", a flight simulator for Unix
  AOTP          "Aces Over the Pacific"
  ASD or A&SD   Microsoft's "Aircraft and Scenery Designer" for MS FS4
  ATP           subLOGIC's "Flight Assignment:  Airline Transport Pilot"
  BAO           The Bruce Artwick Organization
  DOF           Degrees Of Freedom (used in describing flight models)
  F15III        "F-15 Strike Eagle III"
  F3            Spectrum Holobyte's "Falcon 3.0"
  FAQ           Frequently Asked Questions
  FS            "Flight Simulator", usually referring to Microsoft's 
  FTP           TCP/IP "File Transfer Program"
  MS            Microsoft
  MS FS         Microsoft "Flight Simulator", usually referring to IBM
                version
  PC            Personal Computer, not necessarily referring to IBM PC's
  SB            Sound Blaster sound card for IBM computers
  SEE           Mallard's "Scenery Enhancement Editor" for MS FS4 w/ A&SD
  SGA or S&GA   Mallard's "Sound and Graphics Upgrade" for MS FS4
  VLB           VESA Local Bus (usually referring to the video card)



----------------------------------------------------------------------------
                                 INDEX

Section A:  General information about rec.aviation.simulators
   A1.  What is rec.aviation.simulators?
   A2.  Is it okay to discuss games?
   A3.  Can I post binary files here?
|  A4.  What posts *don't* belong here?

Section B:  Flight Simulation Theory
|  B1.  Where can I learn about flight simulation?
   B2.  What do you really mean by "realism" in a flight simulator?
   B3.  How does the flight model influence fidelity?
   B4.  What is a 6 DOF flight model?
   B5.  What is DATCOM?
   B6.  How "realistic" are the various PC based simulators?

Section C:  Flight Simulator Products
   C1.  Which flight simulator is best for me?
   C2.  Can I maintain my FAA currency with a PC-based simulator?
   C3.  Will a FPU/Math Co-processor improve my simulator performance?
   C4.  Are there any space simulators?
|  C5.  What simulators are available for Unix or Sun systems?
   C6.  Are there any Air Traffic Control simulators?
   C7.  Where can I get information on the various flight simulators?
   C8.  Where can I buy flight-related software?
   C9.  Are there any flight-simulator-related mailing lists?

Section D:  Microsoft Flight Simulator
   D1.  What kind of performance should I expect from FS5?
|  D2.  Is there a bug list for FS5?  How about any patches?
|  D3.  What add-ons are available for FS5?
   D4.  What products are available for FS 4 (IBM)?
   D5.  What products are available for FS 4 (Mac)?
   D6.  What is the difference between AAF and A&SD?
|  D7.  Has anyone decoded the scenery file format?  Or the other file
|       formats used by FS 4 and 5?
|  D8.  Is there a way to get real ATC for FS4?
   D9.  Why doesn't my copy of USA East work properly with FS4?

Section E:  Specific Questions on Other Products
   E1.  Why doesn't my Sound Blaster card work with ATP?
   E2.  The KU antenna won't deploy in shuttle, and I can't de-orbit.  Is
        there a fix?

Section F:  FTP Sites
   F1.  Are there any FTP-sites that have flight-sim related material?
|  F2.  Where can I get ACM, FltSim, and Aviator?
   F3.  How do I upload files to the various flight-sim FTP sites?
   F4.  Where else can I get flight-sim related materials?

Section G:  Misc.
   G1.  What happened between subLOGIC, Microsoft, and BAO?
   G2.  How do I submit comments, suggestions, or corrections to the FAQ?


-----------------------------------------------------------------------------


Section A: General information about rec.aviation.simulators

A1.  What is rec.aviation.simulators?

     rec.aviation.simulators is one of many sister groups that are under
     the "parent" group rec.aviation.  This USENET newsgroup is specifically
     for the discussion of air and spacecraft simulators, whether they be
     PC-based, Workstation-based, or "real".  Mostly, you will see talk
     about PC sims, since most of us can't afford (and consequently don't
     have) the real things.


A2.  Is it okay to discuss games like "Falcon" or "Hellcats"?

     Since the software market doesn't really differentiate between games
     and flight simulators, we don't either.  However, you are more likely
     to find game-related simulators on the newsgroups
     comp.sys.ibm.pc.games.flight-sim and comp.sys.amiga.games and others,
     whereas discussion of "pure" simulators on here. 

     If you need help with a game, you are probably going to have better
     luck (and more responses) by posting the the games newsgroups.
     However, if your questions are about flight or combat technique,
     flight modeling, realism, or other related issues, then this is the
     best place to post to.


A3.  Can I post binary files here?

     In the past, some uuencoded binary files have been posted to this
     forum.  In general, most of these files have been airplanes or
     scenery for MS FS4 and such.  Although there's nothing really wrong
     with posting such files to the newsgroup, use a little common sense
     before doing so, and ask yourself the following questions:

	 * How big is the file?  Whereas posting a 2k TRACON/ATC sector
	   is probably not a big deal, a 50k scenery file is probably
	   pushing things.  Most administrators probably don't want to
	   store several large binary files in their news spool
	   directories.

	 * Would it be better to put it up for FTP?  In the case of larger
	   files, you will be best off putting the file at an FTP site
	   such as ftp.iup.edu or wuarchive.wustl.edu, and then just
	   announce its existence on the newsgroup, telling people where
	   they can find it and what it is.  See Section F for a listing
	   of FTP sites that carry Flight-Sim related material.


| A4.  What posts *don't* belong here?
|
|    In general, if it's not related to flight simulation products or
|    thoery, you're better off taking it somewhere else.  This includes,
|    but is not limited to, political discussions, flames, chain letters,
|    government propoganda, and anything by Robert McElwaine or Melvin
|    Gladstone.  Also note that requests for cheats, cracks, or other ways
|    of bypassing copy protection, are not welcome.  *Several* major product
|    developers read this forum, and you're more likely to offend the 
|    people that are trying to make their living than you are to get any
|    help in illegal activities.


Section B:  Flight Simulator Theory
-----------------------------------

B1.  Where can I learn about flight simulation?  

     For the actual flight dynamics, try the references listed below.  You
     would be best off reading books on computer graphics for handling the
     graphic displays:

     Foley et. al., _Fundamentals of Interactive Computer Graphics_,
     Addison-Wesley. [Basics only.  -R D Dorsett]

     _Microcomputer Displays, Graphics, and Animation_, Bruce A. Artwick, 
     Prentiss-Hall, 1985, ISBN 0-13-039322-3.  Previously published
     as _Applied Concepts in Computer Graphics_.  
  
     _A versatile computer-generated dynamic flight display_, Bruce A.
     Artwick, Aviation Research Laboratory, Institute of Aviation, 
     University of Illinois at Urbana-Champaign, prepared for Engineering
     Psychology Programs, Office of Naval Research, May 1975.  
 
     _Flights of Fantasy_, by Chris Lampton, implements completely a PC
     based flight simluator.  While it isn't Strike Commander or Falcon
     3.0, it _is_ much better than any other book on the market for
     learning implementation details of 3d graphical games. [ -Brian]


     The following references are mostly academic texts, and provide more
     of introductions to dynamics and flight dynamics theory.  Additional
     references are listed in B4 and B5.

     _Aircraft Control and Simulation_, by Brian L. Stevens and Frank
     L. Lewis, John Wiley & Sons, 1992, ISBN 0-471-61397-5.  This is
     what a lot of people seem to think Rolfe's _Flight Simulation_
     is.  Develops a 6 dof F-16 flight model. [ -RDD]
 
     "Modeling Flight," in _IEEE Potentials_., April 1990.  
     Performance-based model of bizjet-category airplane; Turbo Pascal
     source available on various ftp sites as "SIMULATE.PAS"  
 
     _Simulation Of Aircraft_, Connelly, Mark E.  Report 7591-R-1.
     Feb 15, 1958, Servomechanisms Laboratory, MIT.  It is a bit dated
     but its what CAE Electronics used to throw at new graduates in the
     Aero Group to educate them. [ -Iab Maclure]

     J. D. Anderson, Jr., _Introduction to Flight_ (McGraw-Hill, 1989).
     [A great intro to flight dynamics.  Read this first before tackling
     the more difficult texts that follow. -B Anderson]

     C. D. Perkins and R. E. Hage, _Airplane Performance, Stability, and
     Control_ (Wiley, 1949).  [One of the best books I've found on the
     gritty details of flight dynamics, including all of the complicated
     effects ignored by all PC flight sims.  Written by and for aircraft
     designers. -BA]

     B. Etkin, _Dynamics of Atmospheric Flight_ (Wiley, 1972).  [A more
     modern treatment.  Relies more on linearization, which I don't like,
     but the treatment is more well organized. -BA]

     R. Von Mises, _Theory of Flight_ (Dover, 1959).  [Another detailed
     book like the one by Perkins and Hage.  This one is even a little
     more involved than Perkins and Hage's, and it's not suitable unless
     you are comfortable with physics and math at the freshman or
     sophomore level.  However, since it's a Dover book, the list price is
     only $13-- a steal considering that Perkins and Hage's and Etkin's
     books cost about $90 each. -BA]

     J. M. Rolfe and K. J. Staples, eds., _Flight Simulation_ (Cambridge
     University Press, 1986), pp. 36-60.  [This is a book about the
     development of flight sims.  Pages 36-60 (Chapter 3) contains
     information on the quaternion formalism for representing an
     aircraft's attitude.  This is the way to do it in a flight sim.  It
     is much simpler and faster than the Euler-angle formalism (i.e., it
     is much more suitable than using the gimbal equations). -BA]

     Another excellent reference is _Spacecraft Dynamics_ by Kane, Likins,
     and Levinson (McGraw-Hill, 1983).  [Also details the quaternian
     formulation, as well as gives transformation equations between the
     various sets of parameters.  Also lists transformation matrices for
     several sets of euler angles.  -JM]

     If you want to see a flight model in action, you will definitely want
     to check out the flight model used in ACM (a Unix-based flight
     simulator for X11 environments.  A separate FAQ for ACM is maintained
     and posted periodically).

|    Tim Tessin writes:
|
|       ACM uses a 6 DOF model with roll, pitch and yaw modeled using 
|       NACA stability derivatives. Also ACM actually models the spring
|       and motion damping effects of the landing gear struts, as well as 
|       the contribution of ground friction by the wheels.

B2.  What do you really mean by "realism" in a flight simulator?

     Robert Dorsett Writes:

     There are two major issues to consider: realism and fidelity.
     Realism is how "real" a system feels; fidelity relates to the actual
     models used.

     Realism is a highly subjective issue: a simulator might model each
     blade of grass on the approach end of a runway, but if the user's
     flying overhead at 37,000', that won't affect his perception of
     *realism* at that point.  Similarly, a graphics system might provide
     a high- resolution database, but if it only uses an orthographic
     projection, it won't win over many pilots!

     Simulation is, therefore, the *art* of providing the expected cues
     and response characteristics for a specified mission.  Most military
     simulators are so specialized that they're optimized for certain
     missions or flight regimes; airline simulators tend to be much more
     flexible (all regime).  For each regime, appropriate feedback must be
     maintained.

     Real-world systems models are usually (but not always) the
     cornerstone of high-fidelity simulation; final "realism", even in
     airline simulators, is obtained only after an exhaustive survey and
     fine-tuning process.  The acceptance process for even a
     production-run simulator can take up to a year.

     A third issue is perception, and the intent of the game as an
     entertainment product.  For example, pilots realize that airplanes
     are essentially very easy to fly and land: non-pilots may expect them
     to be horrifyingly complex to fly, given a lot of the mystique
     surrounding aviation, a lot of which has been enthusiastically
     promoted by pilots themselves. :-)

     All retail flight simulators are just games, and, to some degree,
     help shape and feed off the perceptions of their users.  So if the
     users expect an F-16 to be almost impossible to fly, an F-16
     simulator that IS almost impossible to fly wouldn't disappoint anyone
     except real pilots.  Conversely, a simulator that is actually easy to
     fly might disappoint game-players as too easy, or "arcade-ish,"
     because it IS too realistic.

     In discussing "realism," one should really pay attention to three
     factors:

           1.  The flight dynamics and flight instrumentation. (flight
               simulator)
           2.  The visual system.
           3.  The systems support. (systems simulator)

     The basis for such discussions in this forum should be from the
     pilot, not entertainment, perspective.


B3.  How does the flight model influence fidelity?

     True fidelity in a flight simulator comes from the flight equations
     used in the flight model.  In general, the more complex the flight
     model, the better performance you are going to get, though there are
     instances where even a *good* flight model can lead to poor flight
     simulation (more on that in a minute).

     In general, most of the low-end, low-cost simulators on the market In
     general, most of the low-end, low-cost simulators on the market use
     what is known as a "3 Degree of Freedom", or 3 DOF, flight model.
     This means that the equations of motion only determine x, y, and z
     displacements of the aircraft in space, and then use this information
     to determine the flight attitude.  The actual characteristics are
     based on the so-called "performance" equations, which themselves are
     usually only defined for steady-state situations.  Various other
     characteristics, such as roll rate, must be fudged by the author.
     Some simulations don't even pay any attention to angle of attack,
     using stick input or airplane pitch as the final determining
     characteristic.

     Most high-end simulators use a 6 DOF model, described below, and a
     lot of PC-based simulators tend to ignore these kinds of models
     completely, and rely on a "point-space" performance model instead.

     The equations of motion do not make the flight model, however; they
     merely set the limit on what is and is not possible.  In order to
     support these equations, you must also have good models for finding
     the lift-curve slope, drag coefficients, stability derivatives, and
     other parameters.

     In addition, you have to decide how you want to calculate these
     parameters.  Should you calculate your lift on each wing
     independently, or just the lift on the whole wing surface area? The
     latter method would be faster and easier, but the former would allow
     you to model such flight dynamics as the "Dutch roll" modes,
     stall-spin conditions, and other common effects.  How about downwash
     effects, which alter the effective angle of attack of the tail?
     There are several issues that need to be considered.

     Finally, after you have your flight model together, you need to find
     the parameters that fit your aircraft, so that your *plane* flies
     just as realistically as your flight model does.  For example, you
     could have a high-end, 6 DOF flight model, but if your Cessna 172 has
     the wrong wing area modeled, it won't *fly* like one.


B4.  What is a 6 DOF model?

     Robert Dorsett writes:

     A 6 degree of freedom flight model provides for a fairly accurate
     modelling of the motion and flying characteristics of an airplane.
     It is generally used when the airplane is to be modelled as a "rigid
     body." It considers both rotational (yaw, pitch, and roll) and
     translational motion, both centered around the center of gravity.
     Since there are three axes to consider in each case, this is referred
     to as a six- degree-of-freedom model.  This model actually considers
     twelve variables, since both the instantaneous rate of change *and*
     position have to be considered.  These are referred to as the state
     variables, which are applied to varying matrices of coefficients to
     get the desired fidelity.

     Several people recommended "Aircraft Control and Simulation," by
     Frank L. Lewis and Brian L. Stevens (Wiley Interscience, 1992, ISBN
     0-471-61397-5).  It is a comprehensive work, using an F-16 model as a
     case-study example.  It includes FORTRAN code.

     A couple of people recommended NASA CR-1756, "The simulation of a
     large jet transport aircraft volume I: mathematical model," by C.
     Rodney Hanke, March 1971.  This deals with the simulation of a Boeing
     747.  I've found the second half, containing the aerodynamic data, is
     all but impossible to find, however.

     One of the more accessible references is J. M. Rolfe's _Flight
     Simulation_, a survey of the art.  It has a bottom-line description
     of a 6 DOF flight model, adapted from the Hanke paper.  It is more
     useful for its insights into other aspects of system and flight
     simulation.

     One respondent suggested "A review of flight simulation techniques,"
     by Max Baarspul, in _Progress in Aerospace Science_, Vol. 27, 1990.
     This is a comprehensive monograph (120 pages), detailing the art of
     simulation.  Portions are reminiscent of Rolfe, but he develops a
     flight model for a DHC-2 "Beaver" in much more detail.

     Dan Sharpes dug up the following two:

     _Aircraft Dynamics and Automatic Control_, by McRuer, Ashkenas, and
     Graham, (Princeton University Press, 1973, ISBN 0691080836), which
     apparently has a detailed DC-8 model at the end.

     _Flight Stability and Automatic Control_, by Robert C. Nelson (McGraw
     Hill, 1989, ISBN 0070462186).  Dan transcribed the following
     derivatives for a 747-100 or -200, on page 260:

     Longitudinal
      Mach   Alt   CL    CD     CLa   CDa     Cma     CLadot     CLq
       .25   SL   1.11  0.102  5.70   0.66   -1.26    6.7       5.4
       .90  40k   0.5   0.042  5.5    0.47   -1.6     0.006     6.58
     
      Mach  CMq     CLM    CDM    CmM   CL-De     CM-De
       .25  -20.8  -0.81   0.0    0.27  0.338    -1.34
       .90  -25.0   0.2    0.25  -0.10  0.3      -1.2
     
     Lateral
      Mach   Alt   CyB    ClB     CnB   Clp     Cnp     Clr     Cnr
       .25   SL   -0.96  -0.221  0.150 -0.45   -0.121  0.101  -0.30
       .90  40k   -0.85  -0.10   0.20  -0.30    0.20   0.20   -0.325

      Mach  Cl-Da     Cn-Da    Cy-Dr    Cl-Dr   Cn-Dr
       .25  0.0461   0.0064    0.175    0.007   -0.109
       .90  0.014    0.003     0.075    0.005   -0.09

        W = 636,600 lb
        CG @ 25%MAC
        S = 5500 ft sq
        b = 195.68 ft sq
        c-bar = 27.31 ft

        Ix  18.2 E6 slug-ft sq
        Iy  33.1 E6 slug-ft sq
        Iz  49.7 E6 slug-ft sq
        Ixz 0.97 E6 slug-ft sq
                           
        All derivatives are per radian.


     For more aircraft models, check out the following references:
 
      Robert K. Heffley and Wayne F. Jewell, _Aircraft Handling Qualities 
      Data_, NASA CR 2144, December 1972, 343 pp.  Aircraft described are
      NT-33A, F-104A, F-4C, X-15, HL-10, Lockheed jetstar, Convair 880M,
      B-747, C-5A, and XB-70A.
 
      G. L. Teper, "Aircraft Stability and Control Data, NASA CR-96008,
      1969.  Aircraft covered are A-7A, A-4D, F-106B, T-38, F-5A, F-104,
      F-105B, B-58, Navion, and DC-8.


B5.  What is DATCOM?

     A description of DATCOM, from Dan Sharpes:

     The Datcom is the short-hand title for the "USAF Stability and
     Control DATCOM."  It contains methodologies for determining the S & C
     derivatives for just about any type of configuration.  It does NOT
     contain the S & C derivatives of aircraft (popular misconception!).
     Here's what the Guide to Datcom says:

     "Fundamentally, the purpose of the Datcom (Data Compendium) {OK, I
     was wrong.  Flame me!} is to provide a systematic summary of methods
     for estimating basic stability antd control derivatives.  ...  For
     any given flight condition and configuration the complete set of
     derivatives can be determined without resort to outside information.
     The book is intended to be used for preliminary design purposes
     before the acquisition of test data.  ... there are many cases where
     the Datcom can be used to advantage in conjunction with test data.
     For instance, if the lift-curve slope of a wing-body combination is
     desired, the Datcom recommends that the lift-curve slopes of the
     isolated wing and body, respectively, be estimated by methods
     presented and that appropriate wing-body interference factors (also
     presented) be applied.  If wing-alone test data are available, it is
     obvious that these test data should be substituted in place of the
     estimated wing-alone characteristics ..."

       The Datcom has nine sections:
         1) Guide to Datcom and Methods Summary
         2) General Information (notation, parameters of wing, body,
            section, and planform)
         3) Effects of External Stores
         4) Characteristics at Angle of Attack (static derivatives in alpha)
         5) Characteristics in Sideslip (static derivatives in beta)
         6) Characteristics of High-Lift and Control Devices (section and
            wing forces and moments, including hinge moments)
         7) Dynamic Derivatives (in p, q, r, alpha-dot, and beta-dot)
         8) Mass and Inertia
         9) Characteristics of VTOL-STOL Aircraft (thrust characteristics)

     The methods are a mixture of theoretical and empirical equations.
     Each section starts with a description of the aerodynamics that
     contribute to the derivative as appropriate to the configuration.
     The methods are then discussed with sample problems following.  Next
     are the references, the tables showing accuracy of the methods, and
     finally, the charts.  You'll probably recognize these - several
     authors use them liberally in their texts.

     Where to get DATCOM:

     It's $175.  It's distributed in four binders, is 3,200 pages, and can
     be ordered from:

       Global Engineering
       7730 Carondelet Ave. #407
       Clayton, Missouri 63105

        800-854-7179


B6.  How realistic are the various PC-based simulators?

     Robert Dorsett writes:

     This is difficult to establish, since, again, user enjoyment of a
     product isn't directly proportional to its realism.  Also, different
     users might prioritize different aspects of the simulator, which can
     contribute to perceptions of realism.  An instrument-rated pilot
     might value the fidelity of the nav database; a VFR pilot might want
     a detailed visual database and good "seat of the pants"
     controllability.  A combat pilot will want a challenging adversary,
     whereas a would-be test-pilot would enjoy just flying the airplane.
     So far, there aren't any "combat airplane" equivalents of MS FS,
     which will just let one fly around a realistic civilian database in a
     really high-performance airplane, so it's not really possible to talk
     about "instrument" military simulators, even though a couple provide
     "ILS" approaches.

     Since "package" evaluations ARE a function of user expectations, take
     the following with a grain of salt.

     1.  _Civilian_  Considering flight realism, database design and
	 fidelity, and instrumentation.

         Realism: Elite (Mac/PC), without a doubt.  Developed with a 6 DOF
         flight model, very accurate.  Followed by ATP (PC) and Microsoft
         Flight Simulator 4.0 (Mac/PC).

         Database: Elite, for its nav database; ATP and MS FS 4.0 for
         their visual databases.  Navaids modelled better in ATP.

         Instrumentation: Elite (Mac/PC), without a doubt; ATP and MS FS
         4.0 are about on par.

     2.  _Combat_  Considering flight realism, database design,
         responsiveness, and challenge.

         Flight: "Hellcats over the Pacific"'s (Mac) F6F feels the most
         like any airplane, but its performance near the edges of the
         envelope feels too stable.  Next-up would be "Falcon 3" (PC),
         idiosyncrasies and all; followed by "P-51 Mustang" (Mac), and
         "Aces over the Pacific" (PC).  Near the bottom of the list is
         "Falcon MC" (Mac), with its horrible flight model.

         Database: "Hellcats," again, the most detailed, modelling
         everything from moving aircraft carriers to the ammo cans on
         anti-aircraft batteries.  "Falcon" (3 and MC) are mediocre
         seconds.

         Challenge: "Falcon 3's" probably the best, due to the necessity
         of learning and using the various types of weapons systems.
         "Hellcats" arguably provides the best air combat maneuvering guns
         environment, although enemy aircraft don't die easily enough when
         hit point- blank.  "P-51" has a difficult ACM environment, but is
         only 1:1.  However, when one wins, one has a real feeling of
         accomplishment.


Section C:  PC-Based Products
-----------------------------

C1.  Which flight simulator is best for me?

     The answer to this question, like all others of this type, is "it
     depends on what you want to use it for".  There are a number of
     flight simulators out on the market, and they are (mostly) broken
     down into the following categories:

       * Cheap games -- These would be programs that aren't really flight
         simulators at all, but rather programs that have an airplane or
         some such thing in them.  They are not intended to be flight
         simulators, any more than DOS's EDLIN and Mac's TeachText are
         intended to be word processors.

       * Flight Simulation Combat -- This category would include games
         like Falcon, Aces Over the Pacific, Hellcats, and others.  Some
         of these have better flight models than others, some have better
         combat modeling.  It's really difficult to point out which of
         them is the best, since it all depends on what kind of planes you
         want to fly, and how complicated a program you want.

       * Low-end Simulators -- This category includes FS 4 and ATP, and
         consists of programs that are really intended to be basic flight
         simulation "games" (and I use that term loosely).  You get a
         fairly good flight model at low cost, and also good graphics.
         They are usually intended for VFR flight, and not for serious IFR
         practice.

       * High-end Simulators -- This category includes software packages
         like Elite and IFT-Pro.  They typically will have a 6 DOF flight
         model, realistic performance, high fidelity, and are designed to
         provide existing or future pilots with serious IFR practice.
         They are also considerably more expensive, ranging from $150 to
         $600 or so.


C2.  Can I maintain my IFR currency with a PC-based simulator?

     There is no PC-based program that can, at the present time, be used
     to log IFR hours.  However, the following products are recommended
     for serious IFR practice:

     "Elite" by Azuresoft(?) is an extremely expensive, but highly
     realistic IFR trainer that is available for the Mac and IBM.  There
     are several different versions out, depending on what type of
     computer you have, and they all require a flight yoke of some kind or
     another.  Elite is not a toy, and is probably the most accurate and
     realistic PC-based simulator, both in terms of flying
     characteristics, and instrument panel simulation.  The list price for
     Elite varies from $400 to $700, depending on which version you
     purchase.

     "Instrument Pilot" by Precision Training is an IBM (386 or better)
     based integrated instrument rating instructional simulator.  It comes
     with speech generation hardware to simulate communications and
     includes all equipment necessary for instrument training ground
     school.  List is about $495, and it can be purchased directly from
     the company at (800) 452-0465.

     "IFT-Pro" from Flight Deck is also a good choice.  Though not as
     complex as Elite, it still offers a high level of instrument and
     flight realism, and is an excellent package.  It's also a lot
     cheaper..  list is somewhere around $350.  It is available for IBM
     systems.

     "Cross-Country Instrument Flight Trainer", from T-34 Microsystems, is
     an excellent IFR trainer available for the Mac.  It sells for about
     $150 and can be purchased from Microsystems directly, (800)
     543-2259.

     "FS100", by MDM Systems, Inc., is an IBM PC-based (286 or better)
     flight sim that is intended for IFR training, and has a "pilot
     console" that attaches to your serial port.  The console has switches
     for nav/com radios, throttle/prop/mixture, flaps/gears, etc..
     Databases constructed from Jepp NavData are available for $75 each.
     The company is in Charlotte, NC and their number is 704-523-7400.
     List price is $595.


C3.  Will an FPU/Math Co-processor increase my simulator performance?
 
     Robert Dorsett writes:
 
      Most flight simulators, as with most games, use fixed-point
      integer arithmetic.  They do this both because most production
      machines, until recently, haven't had an FPU, but they also do it
      because this approach is significantly *faster* than FPU
      performance.  
 
      This approach is also used by real-life avionics and simulator
      manufacturers, and obviously is not a "limitation."  A common
      misconception is that an FPU adds more "precision," and leads to
      greater "realism."  This is wrong.  
 
      A simulator must explicitly code for FPU use.  Thus, simply by
      adding an FPU, one won't see any magical speed changes.
 
      So unless a simulator explicitly *requires* an FPU, or *states*
      that it will benefit from an FPU, don't bother buying one, unless
      you can use it elsewhere.
 
     Simulators that don't use an FPU:
 
       Hellcats over the Pacific (Mac)
       Leyte Gulf (Mac)
       ATP (IBM)
       FS4 (IBM and Mac)
       FS5 (IBM)
 
     Simulators that do:
 
       Elite (all versions, IBM and Mac)


C4.  Are there any space simulators?

     Virgin produces a simulator simply entitled "Shuttle".  It is by far
     one of the most complex, detailed, and realistic simulators available
     for the PC, Amiga, and Atari ST.

     Another, older, program, called "Orbiter", is available for Mac
     systems.

| C5.  What flight simulators are available for Unix systems?

     There are currently three flight simulation programs that you can run
     on a Sun workstation running SunOS/Unix, or on X-Window systems:

     Flight Sim (fltsim.tar.Z) -- A flight simulator for Sun systems.  No
     documentation, only some notes on what systems it has been run on
     (Sun3, 4, 386, IPX with 8-bit color).

     Air Combat Maneuvers (acm.2.4.tar.Z) -- A LAN-based combat simulator
     for the X-11 window environment.  It simulates F-16 and Mig-23
     aircraft and is a client/server package, meaning that several players
     can fly against one another when connected to the same server.  A
     separate FAQ is maintained for ACM, and is posted here periodically.

     Aviator (???) -- Stefan Frick writes:
 
      I think it started as a demo-project by two SUN-employees to exploit
      the performance of the GX-graphics-accelerator. One of them is Bruce
      Factor, can't remember the other one...[The other is Curtis Priem
      - Paulo Ney de Souza]  A couple of years ago, you could get the program
      for free from your local sales-rep., but the authors formed their own
      company, called 'Artificial Horizons' and it became a commercial
      product.  The simulator models the FA-18, X-29 and Boeing 727.

     Is uses terrain-data from the US Geological Survey and it gives at great
     sense of realism.  The cost of Aviator is $40 (US) for the liscence + $8
     (US) for the media.

|    Scott Chan writes:
|
|     Silicon Graphics workstations come bundled with a flight simulator
|     located in the demos.  One can take-off, land, and dog fight in a
|     Cessna 150, B747, F15, P38, etc.  Flight characteristics "seem" pretty
|     good; frame rate is good, but depends on hardware platform and detail
|     selected.  Scenery is somewhat sparse.  Instruments are useful but not
|     realistic.  There is also a heads-up display instrument panel.
|
|     Dogfighting takes place against other employees goofing off over the
|     network.  I have no idea if it's been ported to other platforms which
|     have OpenGL...


C6.  Are there any Air Traffic Control simulators?

     "TRACON II" by Wesson International is available for many platforms.
     It is an excellent simulation of ATC, and the PC version can even be
     linked to Microsoft Flight Simulators for multi-player interactive
     flying and ATC.  There are several variants available, including
     TRACON for Windows, and TRACON Pro (suitable for training real ATC
     personnel).

     Recently, Wesson released a "cosmetic" upgrade of TRACON for IBM
     under the title name "ATC".  Mallard is now handling this
     distribution of this product, which is basically a combination of the
     IBM versions of TRACON for DOS and TRACON for Windows (both are
     included in the package).  It is believed that the "ATC" line will
     replace the "TRACON" title and will continue to be distributed
     through Mallard.  "TRACON Pro" however, will remain a
     Wesson-distributed product.  "TRACON" is also available for Macintosh
     systems

     The rumors of the "Microsoft ATC simulator" probably came about when
     some people confused the Tower simulator under development by Wesson
     and BAO with the new TRACON/ATC package, and concluded that a product
     called "ATC" was going to be released by Microsoft, the publisher of
     BAO's Flight Simulator.  Currently, the ultimate publisher for Tower
     is undecided, and no release date has been set.  [ -RDD]


C7.  Where can I get information about the various flight simulators?

     There is an archive that contains reviews, bug-fixes and notices,
     screen snapshots, and other related information that you can get via
     anonymous FTP:

       rascal.ics.utexas.edu  (128.83.138.20)
       misc/av/simulator-folder

     Another excellent source is the WAIS service at quake.think.com.
     Simple TELNET to quake.think.com and login as wais.  Select the
     flight_sim source and ask about the topic you are interested in.
     A list of articles will be given to you, after which you select
     the ones you want to read.  If you wish to keep a copy of an
     article, you can have it mailed to you.


C8.  Where can I buy flight-related software?

     There are a few good places to try.  I am sure there are more, but
     these companies really stand out (feel free to add to this list):

       Egghead Software      (800) EGG-HEAD   Software of all types.
       Flight Computing      (800) 992-7737   Flight-related software and
                                              more.  Very aviation-
                                              oriented. 
       TekMate               (713) 440-5542   TekMate has all subLOGIC
                                              scenery disks, in addition
                                              to other products.
       Electronics Boutique  (800) 800-5166
       Mallard Direct        (800) WEB-FEET
       DataWings             (713) 431-1079


C9.  Are there any flight-sim-related mailing lists?

     Falcon 3 users can join the Falcon mailing list by sending a 
     message to "majordomo@onion.rain.com" with the line "subscribe
     falcon3" in the BODY of the message.

     The Flight Simulator mailing list is mostly centered around MS FS,
     but is not restricted to any particular product or class of
     products.  All requests to be added to or deleted from the list
     should be sent to "flight-sim-request@grove.iup.edu" as should
     problems or questions relating to its operation.


Section D:  Microsoft Flight Simulator
--------------------------------------

D1.  What kind of performance should I expect from FS5?

    The faster your machine, the better off you will be.  Although a
    386 is the minimum recommended processor on the box, you will find
    that you'll want a 486DX *at least* if you want to use all of FS5's
    new features and still get high frame rates.  To give you an idea of
    the "low end" computers, my 386DX/25 gives a frame rate of between
    2 and 5 fps at Chicago with the following configuration:

       ET4000 video card, 320x400 VGA (256 colors)
       Textured sky, gradient horizon
       Textured ground
       Normal scenery density
       No dynamic scenery
       No shadows
       No building textures
       No aircraft texture
       Airport lighting on
       "Enhanced readibility" instrument panel
       No image smoothing
       Low instrument update rate

    I can increase this frame rate to about 3 to 8 fps by removing the
    textured ground.  Removing the textured sky further increases frame
    rate, and switching to the 16-color mode essentially turns the graphics
    display to FS4 levels, but with a slightly lower frame rate than FS4
    (this last one is difficult to measure accurately).  These frame rates
    are playable and acceptable to me.

    A 486DX2/50 or higher will (in most circumstances) allow you to run
    with all the special effects turned on with more acceptable frame
    rates [Can anyone give me some specific numbers?  -JM].

    You'll find that your video card will make a big difference, especially
    if you are running VLB.  Configuring for large disk caches (1 MB to
    2 MB) will further increase performance, and FS5 prefers EMS to XMS.

    The main idea to remember is that you can't expect to turn on all the
    display options and dense scenery and still get high frame rates,
    especially if you have a 386 processor.  FS5 is essential a 486 program,
    and unless you turn down the details to match your processor, you will
    not be happy with the results.


| D2.  Is there a bug list for FS5?  How about any patches?
 
     There sure is, but its so long that I am not including it in the FAQ.
     For those of you with CompuServe access, you can download FS5LST.TXT
     in LIB 2 of FSFORUM for a list of most of the bugs.  This list has
     also been posted here a couple of times, as well as in the Flight Sim
|    mailing list.  It is also available for FTP from ftp.iup.edu in the
|    FS5 directory, filename FS5LST.TXT.
 
     To be fair, however, one must also acknowledge that both BAO and
     Microsoft are communicating with FS5 users via email and other media,
     and BAO has expressed great sincerity in wanting to work with the
     users in making FS5 a better product and in working on hammering out
     all the bugs and problems.
 
|    A patch for FS5 has also been released that clears up most/all of
|    the joystick and sound problems evident in the first release.  This
|    patch is available from ftp.iup.edu in the FS5 directory as file
|    FS5PATCH.ZIP.


| D3.  What add-ons are available for FS5?

     As of right now, the only add-ons that are available are the scenery
     disks distributed through Mallard.  These scenery disks each cover
     a major city (San Francisco, New York, Paris, etc...) in great detail,
     and part of the surrounding area.  With all the details turned up,
     the San Francisco scenery has given frame rates as low as 2 frames/sec
     on a 486DX2/66 (worst case), so these disks are definitely not for the
     CPU-impaired if you want to partake of *all* the features.
 
|    BAO also released a frame counter that tells you how many frames per
|    second you are getting in FS5.  It is available from ftp.iup.edu in
|    the FS5 directory, as filename FC-FSO.ZIP.


D4.  What products are available for FS 4 (IBM)?

     There are several commercial products available for the IBM version
     of FS 4.  Most of these are listed below:

     * Aircraft and Adventure Factory -- Allows you to create aircraft
       models for your A&SD/FS 4 aircraft.  Note that the aircraft factory
       is not and does not modify flight characteristics or parameters, it
       is merely a "paint shop" for designing the *visual model* only.

       The Adventure Factory lets you create interactive FS "adventures"
       that you can use to do a variety of things, such as simulate Air
       Traffic Control.

     * Aircraft and Scenery Designer -- Design your own static and dynamic
       scenery.

     * Facilities Locator -- Both subLOGIC and Mallard distribute a
       facilities locator that can instantly place you at any airport or
       nav-aid in the FS database.  Both products have different
       features.

     * Scenery Enhancement Editor -- Enhance your A&SD scenery files by
       adding custom library objects, day/dusk/night effects, rotating and
       elevating scenery objects, and much more.

     * Sound and Graphics Upgrade -- Provides sound support (and digitized
       sound) for most of the popular sound boards (SB, SBPro, AdLib,
       etc..).  Also has graphics drives for VGA and SVGA modes (only
       certain SVGA cards are supported).

     Scenery disks are also available from subLOGIC and Mallard.


D5.  What products are available for FS 4 (Mac)?

     Currently, the only "add-on" products for the Macintosh are the
     Scenery Disks I - IV from BAO (note that only I - III are needed to
     cover the continental US).

     Note that there is NO scenery designer for Macintosh systems, and the
     last anyone knew, there were no plans for one.


D6.  What is the difference between the aircraft "designers" in AAF and A&SD?

     A&SD is the program that actually allows you to design the flight
     characteristics of your aircraft (within certain limits).  The
     Aircraft Factory in AAF, however, is merely a "paint shop" that lets
     you draw the outward appearance of your design.  It does not allow
     modification of your aircraft's flight parameters.

     In short, if you wanted to design a 727, A&SD would make your plane
     *fly* like a 727, while AAF would make your plane *look* like a 727.
     AAF can also be used to generate "static" scenery library objects
     (.SC0 files) that can be inserted into your scenery files.  Thus, you
     could also put your 727 in a static scenery file, and display it
     parked at your favorite airport terminal.


| D7.  Has anyone decoded the scenery file format?  Or the other file
     formats used by FS 4 and 5?
 
     There is an excellent description of the various FS 4 file formats in
     a file called FSSTRUCT.ZIP, and an FS Structure decoder exists under
     the archive name FSDECODE.ZIP with accompanying files in DES.ZIP.  Both
     can be obtained via anon FTP from the ftp.iup.edu site in the directory
     FLIGHT-SIM.FSDECODE (see section F).

|    FS5STRUC.ZIP is also available, and discusses the currently known FS 5
|    file formats.  It comes with .DES files for use with FSDECODE, above.


| D8.  Is there a way to get real ATC for Flight Simulator v4.0?
 
     IBM users have the following options:
 
      TRACON/ATC, from Wesson and Mallard (described above), can link 
      with two computers running Flight Simulator, and allow you to
      send your ATC messages to the Flight Simulator programs.  With
      special hardware, up to 16 FS porgrams can be linked.
 
      Pilot's Power Tools, a commercial product from Mallard, let's
      you design AAF adventures from your flight plan.  These
      adventures will provide you with full ATC from takeoff to landing,
      and VOC support is included.
 
      Approach Control, a shareware product from John Mechalas, generates
      AAF adventures that simulate airport approach control at any user-
      defined airport.  These adventures provide you with the ATC
      commands needed to line you up for an instrument approach for the
      runway most favored by the local winds.  VOC support is included.
      It is available form ftp.iup.edu in the FLIGHT-SIM.AAF directory.

      ATC Net, also a shareware product from John Mechalas, generates
      AAF adventures that create entire ATC "networks" for your FS4 world.
      You can create several pre-defined adventures as well as define
      several airports all in the same .ADV file.  Full ATC is provided
      from takeoff to landing, and it incorporates the Approach Control
      engine for instrument approaches.  It is available from ftp.iup.edu
      in the AAF directory.
  
|    Mac users can try the following product:
| 
|     FS-ATC is a shareware program from Miika Asunta that uses undocu-
|     mented Apple Events to find the position of your aircraft, and
|     sends messages to the FS program via the Notification Manager. 
|     It also speaks the ATC messages vi the Speech Manager.  The file
|     fs-atc-21-cpt.hqx is currently available from the sites
|     sumex.aim.stanford.edu, mac.archive.umich.edu and their mirrors, as
|     well as ftp.iup.edu.


D9.  Why doesn't my copy of USA East work properly with FS4?

     Most problems with USA East are caused by low memory (these problems
     include:  no runways or buildings displayed when scenery is loaded,
     loss of map or multiple 3d windows, and sometimes very low frame
     rates).  Because USA East is so large, those of you with A&SD
     installed with have to cut their static and dynamic memory
     allocations.  It is also recommended that you install a memory manager
     in order to maximize the amout of 640k base memory that is available
     from DOS.  Last, do not use the SVGA modes that come with S&GA,
     particularly the 800x600 mode.  These higher res modes both eat up
     memory *and* lower frame rates.

     A good way to monitor your available memory in FS is to use the
     Sound Control menu (if you have SOUND.DRV installed) as you modify
     your A&SD settings.


Section E:  Specific Questions about Other Products:
----------------------------------------------------

E1.  Why doesn't my Sound Blaster card work with ATP?

     If you are hearing only the first word of every ATC message through
     your sound card, it is generally cause by an improper setting in the
     SETBLASTER line in your AUTOEXEC.BAT.

     Linda McGarry writes:

      I had the same problem with only 'Los' spoken from my Soundblaster
      card.  After a few phone calls to my supplier, I found out that
      there is another option to the SETBLASTER environment variable that
      is not mentioned in the leaflet that comes with the upgrade, the T
      (type of soundblaster?).

      I have: SETBLASTER=A220 D1 I5 T1  (??)

      (I believe that the recommended value of T for current soundblaster
      cards is T3).

      Hope this helps!


E2.  The KU antenna won't deploy in Shuttle, and I can't de-orbit.  Is there
     a fix?

     Joel Murray writes:

      There is a bug-fix available directly from Virgin.  All you have to
      do is send them a letter stating that you want the fix and enclose
      the UPC code from the back of the box.  I did and have experienced
      NO problems since installing the fix.

      By the way, if you type SHUTTLE /ALL (I think), all of the missions
      become available to you.


Section F:  FTP Sites
---------------------

F1.  Are there any FTP sites that have flight-sim related material?

     There are several places you can go (IP addresses are subject to
     change.  Please use the alias/name if possible):


     ftp.ulowell.edu (129.63.17.1)             A&SD Scenery (US scenery)
         /msdos/Games/FltSim/Scenery           + some IBM utils

     wuarchive.wustl.edu (128.252.135.4)       A&SD Scenery (US scenery)
         /mirrors2/msdos-games/FltSim/Scenery  (ftp.ulowell.edu mirror)

     ftp.uwp.edu (131.210.1.4)                 (ftp.ulowell.edu mirror)

     ftp.iup.edu (144.80.128.8)                A&SD scenery and aircraft +
     (alias for acorn.grove.iup.edu)           general FS info.  Lotsa
         (This is a VAX/VMS machine)           goodies in the various
                                               directories.  Mostly
                                               IBM, but some Mac stuff.

     onion.rain.com (147.28.0.161)             Falcon 3 missions and misc
         /pub/falcon3                          progs/utilities etc..

     cactus.org                                Mirror of the above.  Better
                                               Internet connections, but no
                                               uploads.


| F2.  Where can I get FltSim, ACM, and Aviator?

     The following sites are taken from archie as of 12/2/93:

     fltsim.tar.Z --  isy.liu.se                  /pub/sunview
                      kth.se                      /kth/misc
                      laurel.ocs.mq.edu.au        /Sources/X/Games
                      lysator.liu.se              /pub/sun/games


|    acm-4.0.tar.Z -- ftp.x.org                   /contrib
|                     plaza.aarnet.edu.au         /X11/contrib
|                     sun0.urz.uni-heidelberg.de  /
|                     ftp.denet.dk                /mirror1/X11/contrib
|                     pdq.coe.montana.edu         /pub/mirrors/X11-contrib
|                     sunsite.unc.edu             /pub/X11/contrib
|                     cs.huji.ac.il               /pub/X11/contrib
|                     ftp.germany.eu.net          /pub/X11/contrib
|                     ftp.luth.se                 /pub/X11/contrib

     Aviator can be purchased from QUALiX (yes, that's a lower-case "i")
     for $48 (US): 
 
        QUALiX GROUP, Inc.
        1900 S. Norfolk St., Suite 224
        San Mateo, CA 94403
        Phone:   1-800-245-UNIX, 415-572-0200
        Fax:     1-415-572-1300
        E-mail:  info@qualix.com


     A Windows port for ACM is under construction currently, and a demo
     of ACM for Windows is available at ftp.iup.edu in the FLIGHT-SIM.ACM
     directory.  It requires a 386/7 for the floating point power, and runs
     as a native Windows App.


F3.  How do I upload files to the various flight-sim FTP sites?

     The incoming/uploads directories for some sites are given below.
     Read the README files at the particular site for details on the
     upload procedures.

     Site                     Directory                  Comments
     ----------               -------------              -------------
     ftp.iup.edu              UPLOADS:                   Note the colon
                                                         after the directory
                                                         name-- it's needed.

     ftp.ulowell.edu          /pub                       Archiver puts new
                                                         files out every
                                                         month or so.  Mail
                                                         to archiver after
                                                         uploading.

     wuarchive.wust.edu       /pub/MSDOS_UPLOADS/games

     onion.rain.com           /pub/falcon3/incoming      Mail to archiver
                                                         after uploading.

Remeber to always send mail to the archiver after uploading a file. 


F4.  Where else can I get flight-sim related materials?
 
     One other source, if you don't have Internet access, is to check out
     FSFORUM on CompuServe.  The libraries and forums there cover flight
     simulation of all types, from games to simulators like FS to air
     traffic control and more.  [Does anyone have information on Prodigy
     or GEnie?  --JM]


Section G:  Misc.
-----------------

G1.  What happened between subLOGIC, Microsoft, and BAO?

     Glenn Wallace writes [trimmed for brevity  -JM]:

     Well, it turns out it was BOTH Microsoft and Bruce Artwick that filed
     against subLOGIC...

     Ancient history I know, but I just had to dig this stuff up...

     ------- reprinted without permission, of course -------

     Q65285 PR Court Enjoins Release of SubLOGIC's Flight Simulator: ATP
     Microsoft News Releases (NEWS)

     Court Enjoins Release of SubLOGIC Corporation's Flight Simulator: ATP

     SPRINGFIELD, Ill. -- August 28, 1990 -- Finding that there is a
     strong likelihood of copyright infringement of Microsoft(R) Flight
     Simulator(R), Federal District Court Judge Richard Mills has ordered
     an injunction against the release of Flight Simulator: Airline
     Transport Pilot (Flight Simulator: ATP) by SubLOGIC Corporation. This
     preliminary injunction prohibits SubLOGIC Corporation from
     distributing Flight Simulator: ATP pending resolution of the
     copyright infringement suit filed by Microsoft on December 19, 1989
     against SubLOGIC Corporation in the U.S. District Court for the
     District of Illinois.

     Microsoft filed its complaint alleging that Flight Simulator: ATP
     infringes Microsoft's copyright in Flight Simulator by its use of
     computer code taken from Microsoft Flight Simulator. Microsoft
     requested an injunction in papers filed July 18, 1989 after SubLOGIC
     announced its intention to release Flight Simulator: ATP on July 23,
     1990.

     ----------

     Q67946 PR MS & Bruce Artwick Reach Settlement with SubLOGIC Microsoft
     News Releases (NEWS)


     Microsoft and Bruce Artwick Reach Settlement with SubLOGIC

     CHAMPAIGN, Illinois -- December 21, 1990 -- Microsoft and Bruce
     Artwick reached a settlement today with SubLOGIC concerning various
     lawsuits which arose out of SubLOGIC's planned release of its ATP
     (Airline Transport Pilot) product. Artwick and Microsoft filed
     separate claims in U.S. District Court in Illinois earlier this year
     claiming that ATP would infringe copyrights in the Microsoft(R)
     Flight Simulator(R) product. The agreement settles all claims and
     counterclaims asserted in both federal cases as well as those
     asserted in a state case filed by Artwick.

     The settlement will lift a preliminary injunction which was entered
     by the federal court on July 24, 1990, barring the release of ATP.
     The settlement permits SubLOGIC to release one version of ATP
     containing certain computer code from older versions of Microsoft
     Flight Simulator.

     The settlement acknowledges Microsoft's ownership of Microsoft Flight
     Simulator software copyrights, it acknowledges Artwick's ownership of
     other Flight Simulator software copyrights, and it acknowledges
     SubLOGIC's ownership of the scenery disk software copyrights. As a
     result of the settlement, Artwick will own the "Flight Simulator"
     trademark, but SubLOGIC will continue to publish Artwick's Flight
     Simulator software products for computers like the Apple(R) II,
     Atari(R), and Commodore(R) under license from Artwick.

     "The agreement allows all parties to turn their attention full time
     to developing products. SubLOGIC plans to release ATP as soon as
     possible and to continue development of scenery disks. ATP will
     simulate the flight of five aircraft, the Boeing 737, 747, 767, the
     Airbus A320, and the Shorts 360, between 26 major cities throughout
     the United States. Scenery Disk 12, covering the northeastern United
     States, is now also available for release," said Stuart Moment of
     SubLOGIC.

     "Microsoft and Artwick will continue to work together to produce new
     versions of Microsoft Flight Simulator as well as exciting new
     products such as the recently released Microsoft Flight Simulator
     Aircraft & Scenery Designer. This add-on product for Microsoft Flight
     Simulator version 4.0 allows users to customize their flight
     environment with a powerful scenery designer. The package also
     includes four new aircraft, including a Boeing 747-400 developed in
     conjunction with Boeing," said Charles Fitzgerald, Microsoft's
     product manager for Microsoft Flight Simulator.

     "The Bruce Artwick Organization will continue to be a significant
     player in the development of flight simulation software, not only
     through our work with Microsoft on Microsoft Flight Simulator, but
     also through new products we will be releasing in the future," said
     Bruce Artwick, chairman of The Bruce Artwick Organization, Ltd.


G2.  How do I submit comments, suggestions, or corrections to the FAQ?

     Send email to mechalas@gn.ecn.purdue.edu.

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