After Hours – Choosing a Computer Based Flight Sim

Computer Hardware

There is a minimum level of performance that is acceptable for flight simulators, and because of the increasing complexity of simulation software, the minimum level of performance is steadily rising. Flight simulation is a fiercely competitive business, with new products costing literally hundreds of thousands of dollars to produce. As more powerful computing equipment comes to hand, the software houses use it to the limit. So look to the future when deciding what to purchase so your investment will have the longest possible life. These days, computers are like Lego sets-you start with a bare bones “mother board”, and add bits to it according to your needs and regrettably, your wealth. The most cost effective options that will make a fine flight simulator are listed below.

The first decision is to decide which “chip” to select for your computer. IBM PC based computers use the Intel X86 series, where the “X” can be a 0,1,2,3,4. This code identifies the level of development of the chip. Because of copyright problems, there will be no 586-the next Intel chip has been called the Pentium. Other manufacturers such as AMD and Cyrix make chips that are functionally the same as the Intel chips. The terms “SX” and “DX” describe how the chip does its mathematics. SX do it in software while the DX chip use special hardware that is much faster. Some simulators use the DX capability for greater performance. The last number is the frequency in megahertz of the clock that drives the chip, much like RPM. Generally, more megahertz means more muscle, but the relationship is not linear above 33 megahertz. If you are buying now or in the next six months, a computer based on the Intel 486DX33 chip is recommended. Equipment based on the 80386SX will work, but is too slow in many cases, giving jerky presentations. A 286 based computer is a waste of space. You can buy a computer based on the 486DX50, but in practice they are generally only 10% to 15% faster than the DX33 system, rather than the 50% often claimed as other “throttle-necks” limit performance. However, the cost can be as much as $500 more, which is not good value for money. There are some decisions to make about the mother-board. Try to find a computer that will allow you to replace the 486DX33 chip with either the 486DX66 “overdrive” chip or the Pentium or both, as you will then have an established upgrade path. The 486DX66 improves performance by about 70% over the 33DX version, and the Pentium by 200-300%, especially for simulations specially written for this processor.

If you have opted for the 486 chip, buy a mother-board that provides “cache RAM”. (“RAM” is short for Random Access Memory. ) This is a special area of high speed memory on the motherboard that stores instructions for the 486 chip. If the next instruction or piece of data is present in the cache, speed will be increased. Most computers offer 256 kilobytes of this type of memory. Less will do, but having at least some instruction cache capability is a distinct advantage for these faster chips.

Some motherboards are now offering a “local video bus” connection for graphics cards. Without getting too techo, most of the lego blocks sit on a connector called an “ISA Bus” which operates much more slowly than the main computer chip. To speed things up, manufacturers of the computer boards are now offering access to the “Local Bus” which drives the RAM memory. Theoretically, putting the graphics card on a Local Bus should greatly improve performance, but at present the speed-up is only 10% to 50%. Later graphics cards will be optimised for this feature and could improve performance much more. This feature could be considered as an investment in the future.

The computer has two more types of memory – RAM in which the computer uses “on-line” and hard disc memory where programmes are stored awaiting the call to RAM. Don’t be chintzy here, get plenty of RAM as it adds speed. My recommendation is to purchase eight megabytes and be prepared to add some more later. RAM is relatively cheap at about $65 per megabyte.

Many simulations use more than 10 megabytes of hard disc space-Strike Commander uses 35 megabytes! A basic system containing DOS and Windows 3. 1 and some core applications such as a word processor and a spreadsheet uses about 30 megabytes of disc space. (You have to have these core applications to justify the purchase to your spouse!) Simple arithmetic says that you won’t fit a large game on a 40 megabyte disc. Recommendation: purchase a hard disc of at least 130 megabytes, and preferably 250 megabytes. The marginal cost of the larger drives is quite small, so ask for the additional price of a larger drive.

A main element in the performance equation is the way graphics are handled. This part of the system has become prominent only in recent times, as applications “go graphical”. Flight simulators are very graphical, so choose carefully. A graphics accelerator card is in effect a computer within a computer, and has the specialised function of drawing lines, boxes, filling areas etc on the video screen. These functions take a long time for the main chip, so a graphics chip can speed things up dramatically-often as much as 5 to 10 times. Most simulations are written for DOS, but graphics accelerator cards can be optimised for DOS or Windows, but rarely both. Ask for a graphics accelerator that works well for DOŠ applications if you want top speed.

Floppy disc drives are cheap and reliable at $100 a pop, so buy one of each of the 5 1/4 inch and the 3 1/2 inch formats.

The Trustmaster family is the ultimate in flight control systems and when interfaced with a capable machine provides a highly realistic flying environment. The Thrustmaster series contains three major components, the Flight Control System (FCS) control stick, the Weapon Control System (WCS) throttle and the Rudder Control System (RCS).

You can ponder forever over which video monitor to buy, but price quickly brings a touch of reality to the purchase. For most simulations, a 14 inch screen is fine. Sometimes flicker is a problem, and a non-interlaced monitor avoids the prob- lem at a price. Do however buy a “Super VGA” monitor, this is now the defacto standard.

Trap a mouse as most games use a mouse for initial selections. I will cover flight controls later. You can use a mouse as a joystick, but I don’t recommend it. Mice are not born equal and some turn ratty very quickly. I like the feel of my Microsoft mouse which has the drawback that is it five times the cost of a cheap mouse. New versions are appearing that have no moving parts and these deserve a look.

The last piece of hardware to buy is a sound board. The PC comes with a tiny tinny speaker, but most games support special boards so that you can hear the engine, air rushing past the airframe, chopper blades, voices, missiles firing etc. A pilot’s audio channel is underused during a mission, and in a workload intensive situation, sound adds a lot to both the enjoyment and control of a game. The two standards are Soundblaster and Adlib and boards come with a range of options and prices. Some have interfaces for a CD-ROM, so get one of these so you will be ready for the huge multimedia games when they arrive. Find a good set of speakers to compliment the sound. I use a set of Sony speakers designed to extend a Walkman, and the sound is excellent. If you can get away with it, you can even patch into the family stereo with this equipment!

Tuning the Computer

You might have agonised over the countably infinite op- tions for purchasing the hardware, you can also agonise over the way your computer is tuned.

My first recommendation is to ensure the system comes equipped with Microsoft MS DOS 6. 0. There are other disc operating systems (DOSS), but they are not mainstream. MS DOS 6. 0 has a handy utility called “MEMMAKER” that I will describe later.

There are two critical files in PC systems: CONFIG. SYS and AUTOEXEC. BAT that the computer uses to optimise itself for a particular user. These two files are placed in the front of the CD-ROM that the computer first looks to when starting. For flight simulator application, use the KIS principle – Keep It Simple. The setup described here will provide a computing environment that will maximise the speed of most applications. If people try to load up your memory with a pile of junk like virus protectors, pop up calculators and so forth, tell them to RAM it on their own machines! If you can, get a knowledgable friend or the computer retailer to help you here. This subject can be terribly confusing to a newcomer to the intricacies of PC computing, and you need to make the right choices or your Hornet will turn into a blowfly.

Many complex books have been written on this subject, and there is not enough space to cover the options so if you are doing it for the first time, use the “monkey see, monkey do” approach. You can make or modify the files using the EDIT utility included with DOS 6. 0. Before messing with these files, make a “boot disc” as described in the DOS manual so that you can restart the computer if you make a mistake.

CONFIG. SYS is loaded first by DOS and tells the system which drivers to use – these are devices that set the way the bits of the computer talk to each other. You need drivers to access all that fancy RAM you bought. My recommendation to start is:

After amending or creating these files and saving them in the root directory of the hard disc drive from which the computer starts, usually C, restart the computer by turning the power off at the C:\> DOS prompt, waiting 30 seconds, then turning the power back on. The new files will load and your computer will now be ready for the next stage of tuning. At the C prompt on the screen, type MEMMAKER and computer magic will happen, if and only if you follow the instructions on the screen. Use “Express Setup” for a start as it will achieve all you need for this simple configuration. Ifyou need to add other programs to your computer, especially Windows 3. 1, you may need to use the “Custom Setup”.

Aim to have at least 600K of RAM memory free with no free by typing MEM. Look for the “Largest executable pro-programs running. You can find out how much space you have , gramme size” – my system typically has more than 610K free and runs all flight simulators without a problem, except for those such as Jetfighter II which is very fussy about its memory settings. Newer simulations tend to use standard memory settings, but you need to have the extra RAM and use EMM386. EXE to access this memory for faster graphics and special features such as flight cameras.

Flight Controls

So you have spent $4000 on the hottest computer in town- don’t go cheap with flight controls or you will discover the principle that a chain is as strong as its weakest link.

The minimum you need is a joystick as using the mouse or the keyboard for flight controls is virtually useless. There are many to choose from starting at about $30. Spend the extra money to get a stick that has a nice feel and precise action. I recommend the CH Flightstick at about $105 as the minimum for serious flight simulation work. This stick has trims and a throttle, and performs very well.

If you want the “creme de la creme”, I suggest you use the Thrustmaster series. Most new games come with a special set of software interfaces for this equipment, which indicates the regard the simulation writers have for these flight controls. There are three components: a Flight Control System (FCS), a Weapon Control System (WCS) and a Rudder Control System (RCS). If you purchase all three, you will have as complete a set of Hands on Throttle and Stick (HOTAS) controls as is included in a modern fighter such as the F-16 or the F/A-18.

The FCS is modelled on the F-4 Phantom joystick, plugs into the normal joystick port and provides additional buttons including the “hat” four way control that is often used for trim in fighters. In most new games the hat controls the view from the cockpit which is brilliant – I will cover this feature next month when I review Strike Commander. I added a small modification as suggested in the documentation with the RCS to make the stick work fully with Microsoft Flight Simulator 4-the mod consisted of a toggle switch for one wire and took about 20 minutes to install.

The WCS is also simple to install, as it plugs into the keyboard port and the keyboard plugs into the WCS. You set a DIP switch to give the correct controls for each game. The WCS provides a throttle, plus seven other buttons to control flares, chaff, targets, weapons, brakes, flaps etc. I remember how long it took me to programme my left hand to use the Mirage radar stick which is like the WCS, but when you get the hang of it you are seriously lethal! You can also buy a U-PROM chip for the WCS and download your own set of controls so that all your games use the same buttons. I have this option but have decided to use the DIP switches until a new game comes out which does not include a programme for the DIP switch.

Rudders make up the complete set. These are strongly made and again are simple to install – you plug the rudder cable into the games port, then through an adapter you plug the joystick into the rudder cable. This is a simple way to get both controls working.

You don’t have to disconnect any of these controls if you need to do something boring on your computer like writing a letter. I suggest that you start the system with the WCS throttle in the off position. As long as you don’t touch it, all your software will work normally. The WCS generates key- board characters in response to movement of the throttle or presses on the buttons, so no great disaster will occur if the kids press one of the buttons while you are writing your memoirs.

So how does the Thrustmaster system stack up. In a word – brilliant. The combination of these controls gives a PC based flight simulator a “real” feel. My first test was on Microsoft Flight Simulator. By selecting two joysticks from the menu, and decoupling the rudder from the ailerons, it is possible to taxi with rudder and complete highly realistic crosswind landings, using the crab or kick-straight technique, whichever you prefer. Having a throttle in your hand also helps with precision speed control on finals.

The WCS was excellent in the fighter simulations. My kill rate increased substantially through using the throttle, speed brakes, targeting and weapon selection with my left hand. A bogey at five o’clock? No problem-snap into dogfight mode, push to full burner, and that pesky MiG-29 is taking a Sidewinder on the lips in short order! The rudders are the most expensive option, and if you are strapped for cash, you can delete them for most simulations with minimal effect.

Conclusion

If you buy a “full house” system of the type I have described, you will have, for an investment of less than $5000, a flight simulator that rivals (sans movement and real cockpit duplication) expensive military and airline models costing literally millions of dollars. The quality of the combination of a fast computer, a full set of controls and high quality software provides an operating environment that is highly realistic and which can help you keep current for a fraction of the cost of physical flying. You can also have a lot of fun as well.

Flying training schools, whether commercial or aero club, should seriously consider this equipment as a supplementary flying training aid. There are many times when aircraft are not available, the weather is too bad, or the student needs to have a procedure explained without the requirement to fly a whole sortie. In aero clubs, I can see this facility being a drawcard for people entering aviation and needing additional help to train on a limited budget. The first clubs and schools to appreciate this will be big winners.

Using products such as Microsoft Flight Simulator 4 with Australian Scenery, it is possible to train a student at their own airfield, complete with instruction on procedures, frequencies and flying skills in a range of weather conditions. Long navigation exercises can be flown, aircraft landed away, aerobatics taught etc.

I would like to see the results of an experiment with a mixture of simulation and physical flying. Students could pay (say) $10 per hour to use the computer and an additional (say) $20 for an instructor. The cost of the computer would be recovered in one year if it were used for only 10 hours per week. Initial procedures training could be conducted in a risk free environment, enhancing the value of airborne exercises. If any flying school wishes to try such an experiment and needs more information or advice than is contained in this article, please contact me though Australian Aviation – I would be delighted to assist.