baffmeister

One slug has a mass of 32.1740 lb (14.59390 kg) based on standard gravity, the international foot, and the avoirdupois pound.[2] At the Earth's surface, an object with a mass of 1 slug exerts a force downward of approximately 32.2 lbf or 143 N.[3][4] Now I get it!

To calculate inertia, find a ThirdWire aircraft with a similar configuration and mass, then copy the inertia values. [I know that sounds lame but I tried a simplified approach once and the results were off the charts.] Just an observation but in the Hud De-Bug mode the Inertia values are shown in Slugs-Ft^2 [whatever that is ]

A single tile walled town, somewhere over New Dhimar. Almost 8 hours of work to tod one tile but I would like to add a couple more versions.

Data.ini for the TW MiG-21F attached. This has the same aerodynamic changes as the latest Bis FM's. The rack/rail weights have been adjusted based on the Bis info and I added Svetlin's nose gear edit but forgot to have a look at it in game. The ammo load out has been increased to 60 rounds, based on information obtained from another thread. There may be a possibility some early Soviet versions only had 30 rounds but it seems like the 60 round load out was standard by the time the type was getting exported. Canopy is on Shift0[zero] The lighter weight MiG-21F seems to have a bit better chance of getting a guns solution at the low end of the speed range but I'm a bad shot and haven't managed it yet. I did do some successful evasive maneuvering in the low speed range and think you can probably force an overshoot against most of the ThirdWire types but watch the sink rate at low altitude. Here it is: MIG-21F_DATA0.96.zip

I like the way this worked out!

Hmm, possible later update? The Have Doughnut document mentions 60 rounds as well.

Thanks. Darn, I wanted more.

I just noticed the stock TW MiG-21F-13 [aka Fishbed-C] has only 30 rounds of ammo while the sources I've checked say it carried 60 rounds. Is that an old issue that I should have known about or something that hasn't been noticed before. [hard to believe]

Thanks for the update ideas. I will test the nose gear edits and look into the other improvements. This project is becoming a long term one but there may be a formal upload at some point in the future so it's good to get information on any past mods that would make for a better package.

Not sure what the actual aerodynamic limits might be for an F-16A but the type did have an automatic G-Limiter installed. A long time ago someone came up with an aerodynamic G-Limiter for the stock TW F-16A. I think it was Caesar who passed it along to me. The modified FM is attached at the bottom. The mod works quite well if you fly in a normal fashion with just temporary high G turns. At high speed if you just pull back on the stick and keep it there it will piss away all your speed until you get below about 9 G's. The limiter kicks in a bit over 9 G's so theoretically if you kept the plane at exactly 9 G's at a high enough speed it could sustain that but I doubt that's possible in practice. I don't fly the F-16 much so not sure if this mod has any affect on the AI. Here's a "drop in" F-16A data/FM with the only mod being the G-Limiter: F-16A_G-Limiter.zip

I agree, that's probably the best approach to get what you want. It isn't something that I even noticed but if you get a more realistic look please pass along the edits.

The previous emergency thrust levels were overstated based on the flight manual and other sources. The ThirdWire default values are correct up to about 13000ft. Based on what I know now, I would actually have to model LESS thrust above 13000ft to more accurately model the Bis engine performance.

Test FM's for the two ThirdWire MiG-21Bis models attached at the bottom. The main objective with these is to try and model the high alpha behavior as described in the flight manual. I had to make way more changes than expected to add only about 5degs to the existing AoA range. With the revised FM's I'm trying to model some lift transfer from the outer to inner wing panels. According to a document I read this occurs in the 20-25 deg range. To get a smoother transfer I went with the low end of the range at 20deg. The edits to the outer wing panel limit the CLmax to what it would be at 20deg, based on a straight line variation. The "surplus" CLmax has been added to the inner/forward wing panel that has a revised stalling angle of 20deg, so it transitions to the CLmax slope at 20deg and continues up to a new AlphaMax of 33deg, versus the original at 27.66deg. Some additional CLmax has been added to model the added lift available at 33deg. Some additional edits were required to the StallMoments and the StallXACShift tables to reach the higher AoA range. Here's a description of the idle power level flight stall behavior at 5000m/16400ft from the Bis flight manual, with some comments regarding the revised FM's in brackets: 340-370kmh /184-200kts: pre stall buffeting [around 170-175kts] 280kmh / 151kts: Aileron deterioration [somewhat noticeable] 230-240kmh / 124-130kts: Wing rock develops but pitch stable [no noticeable wing rock] 220-230kmh / 119-124kts: Aircraft starts to pancake [ I assume that means a high sink rate but pitch stable, which it does] 200kmh / 108kts: Large wing rock up to 50deg left/right at about 6-10deg sec [ Nope! ] I did some back to back testing with the stock and revised FM's and the sustained G remains about the same but the revised FM generates a higher instantaneous G due to the increased lift available at 33deg. The only way I found to check the low speed behavior was some calculated data from the CheckSix website. The test involved a very low speed turn at mach 0.22 / 133ktsIAS at 5000ft with two R-60's and 50% internal fuel. It was quite difficult to fly accurately but the best results were within +-2sec of the calculated data. The calculated data is 52sec for a 360deg turn. [6.9deg/sec] Some additional edits from the flight manual: Gear limit speed: quite high at 600kmh / 324kts. The sop's for landing call for gear down first at 550kmh/297kts then approach flap at 500kmh/270kts with full flap selected at 400-420kmh / 227kts. Flap limit speed: Not even mentioned in the flight manual and no description of the "floating flap" system! I based the flap1 speed on the sop's and the flap2 speed is the TW original. The rack weights have been adjusted using the info from the technical manual and the MiG-23 800L tank has been added as an option. Recommended take off rotation angle is 11-13deg. The manual calls for early aft stick, maybe due to ground effect issues, but I find 130-150kts, depending on weight, and 13deg AoA gives a nice lift off at the proper speed. Typical approach speeds at light weight are quite high at 180kts but that's probably due to over the nose visibility issues. The target touch down speed is considerably lower at 150kts. The canopy works with Shift0[zero] I've found the additional AoA range quite useless during dogfights due to the rapid speed loss. It's sometimes useful for evasive maneuvering but that's really a last chance maneuver, it's better to keep the speed up. An interesting document here describing the U.S. tests on a MiG-21F. https://theaviationist.com/wp-content/uploads/2013/11/havedoughnut.pdf I have read some other documents describing how skilled U.S. aggressor pilots could trick the rookies into low speed turn and burn dogfights with the MiG-21's and F-5E's but once the lesson was learned the results were much different so better not to go there. Even the ThirdWire AI will be flying rings around you! Revised FM's here: MiG21bisFMs0.96.zip I'm going to modify the light weight MiG-21F as well, it should be ready soon.