Flight Modeling in Helo Sims by Zero G
	I have said that I would do up an article explaining what Apache Havoc does both right and wrong when it comes to the flight model, so here it is. I will say up front that this isn't a list of things that should be fixed in Apache Havo, rather it is for those who asked for a comparison of the simulated model to real helo flight. (A good starting point to make it more realistic to fly would be to run at 2X game speed, Ctrl+ .) Apache Havoc is in my opinion the best helicopter flight model on the PC. For me, this (and other things) makes it hands down the best helo sim out there. While I want to talk only about the flight model here, you need to know where I am coming from. I am a huge Apache Havoc fan and Todd Gibbs has done a super job with his work on this sim. (So has the rest of the team, but Todd has done some very special stuff.) Some of the things that are going to get better when 1.1e is installed: torque will go the right direction for the helos now. Torque is now a dynamic variable that is dependent on how much collective is pulled (the more collective pulled the more torque you will have to deal with). Tail rotor use will no longer kill your ability to gain forward airspeed (this will have to be done through a command line addition). In addition, there will be some other command line additions I will talk about that I have used to tweak the flight model to make it a bit better. Many thanks go to Richard (Flexman) Hawley for his great command line list for this sim that can be found on his site: Chapter 8. Here is how I have my game set up: wind is on, cross coupling is off and retreating blade stalls are on. The command line additions I use to tweak the flight model are as follows: /drv:2 /dra:5 /drd:0.5 /dtrd:0.0 /drbs:1.5. I also use a few other options that tweak other parts of the game. Just check out Richard's site and decide for yourself what you want to add. There you will also find an explanation as to what I have tweaked on the flight model (FM). Some of the listed commands will not work until you have the 1.1e patch. From Lift Off Forward I will start from the time of lift off and move from there. The first problem is well known and you see it the moment that you start to lift off; the total lack of ground handling. It is of course not right that your helo sticks to the ground until you are airborne. This is one of the things that we helo pilots use to be sure that we have not snagged on anything or to pack down snow that is being landed in. Click to continue		A rolling or sliding take-off is also used in a helo that is loaded to maximum weight, especially if you are at a high density altitude. The same can be said for landing a helo, there are times when sliding on landing can be very useful. Needless to say this is one item that I hope is fixed for Comanche Hokum. New for 1.1e Patch New for 1.1e the helicopters will now perform correctly when they are lifted off the ground. The nose will now swing opposite to the main rotor direction and you will have to work the pedals much harder to keep the helicopter going where you want it. The pedals can no longer be put in one spot and held there until you are ready to let them off all together. I found the climb rate of the helicopters to be excessive in the hover as most helos get a best rate of climb at 45-60kts. This is not the case in A-H; rather you lose ability to gain altitude as you speed up. Here are the real numbers for the AH-64D Longbow. Maximum rate of climb vertical in average conditions 1255 feet per minute, maximum rate of climb 2370 feet per minute. As you can see there is a gain of over 1000 fpm (almost double!) by being at the Apache's optimum climb speed instead of a climbing hover. These numbers are the official ones coming from its makers so they are probably taken without a weapons load so that they look good. I would expect normal performance to be under these numbers by a bit. Apache-Havoc seems to get climb rates right when moving, I got just over 2000 fpm with full load at 60 knots and about 1850 fpm at 75 knots. Things go very wrong, however, when you stop and try the same climb. I was hitting climb rates of 3000 fpm in a hover, more then double the actual numbers. I have included a picture of a common power chart for helicopters. It may not perfectly match the Apache or the Havoc but it is an average across most helos. Go to Page Two
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