Tuesday, December 29, 2009

F-86 update

I'm traveling a lot these days, so not much time for Hangar work. Here's a screenshot of the progress on the F-86.


In this blog's "links widget" there is a link to openAE, a site worth visiting. (Hmm, back when I was in college that last sentence would have been gibberish.) The folks there are about to release the next version of OpenDatcom, which is a GUI interface for the U.S. Air Force's Digital DATCOM. DATCOM was created to aid in estimating the aerodynamic qualities of airplanes based on their geometry. This is very useful for making JSBSim configurations, however few people have been willing to deal with the user-unfriendliness of DATCOM. OpenDatcom may be the solution!

Thursday, December 24, 2009

Merry Christmas!

For those of you who would like to see how NORAD tracks Santa, the NORAD folks explain it here: NORAD Santa Tracking

Friday, December 18, 2009

PNG versus SGI

I have a new version of AC3D, which means I can now start using PNG textures, which compress to a smaller size than the SGI textures do. One thing that seems a bit disconcerting is that it takes forever for GIMP to compress the images, which leads one to wonder is the de-compression just as slow? Has anyone noticed a significant difference in load-time for models using PNG textures?

Thursday, December 17, 2009

In a Sabre Mood

I'm in the process of converting Detlef Faber's F-86 into a later model F-86F-25, the type with wing fences and no slats. The texture will be the 512th FDS livery, aircraft number 52-5350, as mentioned in a previous post about the Wings Palette web site. To help you get into the mood too, here's a film of the 526th FBS getting their new F-86's!


Tuesday, December 15, 2009

Road block

I'm slowed down a bit, partly due to heavy workload, and partly because I just did an OS upgrade. Spent all day getting Slackware 13 installed and set up the way I like it. Of course my email address book won't import properly, so I have to recreate some of it. Prestes, could you send me an email please so I can add you to my contacts again?

Friday, December 11, 2009

iS4g Group

The iS4g Group is a group of aircraft modelers in Italy who have been making models for CFS2 and later versions of MSFS. They have a lot of models available at Sim-Outhouse (see link in side bar). The CFS2 models are usually convertible for FlightGear using the "threedconvert" utility. Like any such conversion from MDL to AC format, the next steps are:

1) Combine all objects into one object (I call it "fuselage")
2) Optimize the vertices and surfaces (removes duplicates)
3) Cut away surfaces into new objects for later texturing and animation
4) Prepare 3D cockpit by making cockpit sides and other inner surfaces
5) I make all surfaces one-sided, except for propeller disk
6) Convert textures to SGI format, then apply textures
7) Make animations file, add DavePack parts

That's a basic outline. I often redo the tires completely, and the canopies usually need a lot of work.

Wednesday, December 9, 2009

Creative Commons license?

I visited Prestes Hangar to try out the T-27 model, which is based on the A-29B model from my hangar, which is in turn based on an AlphaSim Tucano model. One of the licenses used at the site is the Creative Commons license, which I've heard of but never looked in to. It seems very similar, if slightly more restrictive than the "Freeware/non-commercial" license I've been using. It has the benefit of being known, specific, and well documented, including having a nifty website to link to. Maybe I should just switch to the CC license? Anybody have experience with this license?

To be specific, Prestes Hangar uses the "by-nc-sa", or "Attribution, Noncommercial, Share Alike" version of the CC license, which seems most fitting for Dave's Hangar.

Tuesday, December 8, 2009

Aircraft skin resource

There's a great resource for aircraft skins here: http://wp.scn.ru/ . Lots of great texture ideas to be found!

Monday, December 7, 2009

Maachi C.205 Veltro

The Veltro is progressing and flyable. I just started looking for the author, Alessandro "Alex" Casadio, to get permission to release it in the hangar. It still needs a lot of work, but it sure is pretty already.

Wednesday, November 25, 2009

Grumman F3F project

This airplane is visually interesting, but I think it'll be underpowered and visibility will be poor. Carrier landings might be a bear. The model is based on a Paul Clawson F3F for FS98. The original was a bit too low-poly for today's technology, so I'm replacing everything piece by piece, using the original as a scaffold. Gear retraction is going to be interesting too!

Monday, November 23, 2009

A-1H ordnance load

Trying to decide on an ordnance load for the A-1H Skyraider, USAF version. Here is an interesting website on typical loads for an A-1. The CBU-25 looked interesting, so I made some of these bomblet dispensers from circa 1970. We don't have CBU yet in FlightGear, AFAIK, so the submodels for it should be interesting. And we don't have troops as targets yet, so the CBU may not be very useful.

Wheel spin

Modeling tip here. Spinning wheels in FlightGear use the "spin" animation, which is looking for an input using the units "rpm", or rotations per minute. I base the input on a property available in JSBSim called "fdm/jsbsim/gear/unit[n]/wheel-speed-fps". Be sure to change the "n" in the property name to match the number of your gear unit, as defined in the FDM configuration. For most of my models unit 0 is the nose gear, unit 1 is the left main, and unit 2 is the right main, but you should check the FDM config to make sure.

So, how many rpm's does a wheel of diameter "D" (in meters) spin at when moving at "wheel-speed-fps"? I use (5.82 / D). I'm going through all my models now and changing this because I had previously guessed that the spin animation units were degrees/sec, but I was wrong.

BTW, using separate speeds for each wheel allows them to spin realistically in a turn. Zoom in on one of the models in the hangar while it's in a tight turn on the ground, and you'll see the inside main wheel turning at a slower speed than the outside main wheel.

Friday, November 20, 2009

DavePack bug fix

Fixed a bug in the Mk-81 XML's. Reduced LOD range for bombs to 2 kilometers. Indentation cleanup.

Wednesday, November 18, 2009

Weapons fixes

NicQ has added some fixes to the DavePack bombs and rockets. This should make them behave better. New version is 3.9.

Monday, November 16, 2009

OpenAL pitch

I've been working with NicQ on sound files for the piston engined airplanes, and we've found out some interesting things about the way OpenAL handles sound pitch. First, the API wants octaves as a pitch input, with "1" representing the unmodified sound file. Therefore, a pitch input of 0.5 means one octave lower, and a pitch input of 2.0 means one octave higher. That means that the pitch value needs to be: log2(input/ref) + 1.0, where "ref" is a reference value associated with the pitch of the unmodified sound file, and "input" is a flightgear property value to be compared with "ref". For example, if you have a sound file which represents the engine sound at 1000 rpm, then "ref" is 1000, and "input" is the property "engines/engine[n]/rpm".

One other thing, OpenAL appears to limit the pitch modification to +/- one octave. This means that to create sound for an rpm range of 500-3000 you would need two sounds to cover the range.

Saturday, November 14, 2009

Lots of new stuff

New DavePack, F-105, Mirage-IIIC, MiG-21 (formerly known as MiG-21MF), AD-4, AD-6, and F-106.

DavePack 3.7

As part of my effort to get the large piston engines sounding right I've added some new sound files to DavePack. These files are non GPL-able, so I've given DavePack a "Freeware, non-commercial" license now. I also included some pilot models in the last version of DavePack which are non GPL-able, so I'm a bit late with the license change.

New MiG-21 on the way

FlightGear user "eRobo" is working on a new MiG-21 model. If seen it, taken it for a test drive, and can say it's a great model! The MiG's in my hangar are based on some older, low-poly models from AlphaSim, and there's only so much that can be done with them. eRobo plans to hangar the MiG at FG CVS.

Wednesday, November 11, 2009


Someone on MP today asked where he could find a CH-53 model. I looked around and found one at simviation.com that would make a great project. Anyone looking for a project? I won't be working it, mainly because I don't know a thing about choppers.

Tuesday, November 10, 2009

Elevon mixing?

Does anybody know how the elevon panel deflections on delta airplanes (like F-106 or Mirage III) were mixed? Did the inner and outer elevons move together, or was there some differential there? How much did each panel deflect for roll and pitch?

I just guessed for the Mirage model, and could do the same for the F-106, but I'd rather get this right if I can.

Monday, November 9, 2009

Sea Fury, DavePack updates

The Sea Fury model is updated. It's in a usable state now, but still needs a lot of detail work.

DavePack now has an Air Force and a Navy pilot figure, both untextured at the moment. There is also a regular gear indicator (three green lights) and a navalized indicator (with additional holdback and hook lights).

Wednesday, November 4, 2009

T-38 and Sea Fury

I worked on some old models today. These are two of the older one's I have. The T-38 is very low-poly, and I wouldn't bother doing a conversion on it today, but it filled a niche when I first built it, and it looks good enough to keep around. Note: this is the only model in my hangar that uses the JSBSim capability to model a modulating afterburner. The first half of the throttle range maps "mil power" from idle to 100%, and the second half of the range maps the afterburning range. This might be the preferred method for you depending on your throttle hardware.

The Sea Fury is one of the first Alpha Simulations conversions I did. I put it aside a couple years ago, and it hasn't been kept up, until now. It's posted at the hangar as a project, and I'll be bringing it up to par with the other airplanes.

Tuesday, November 3, 2009

fgo, launcher app

I just downloaded Robert Leda's python-based launcher app called fgo. It's fun to play with, and looks more lightweight than fgrun. It can be found here. Note: you'll need the PIL (Python Image Library), as well as a fairly modern version of python.

New drag 'chute testing

User "someguy" discovered a bug in the new drag 'chute system, so I've put in a fix (I hope) to the F-4E model, which is now posted at the hangar as version 2.6. If all tests properly the new system will:

1) make chute animation visible over multiplayer
2) cause the 'chute to rip off if deployed above 200 kts.

A note on fuel tank priority

One limitation on the use of the "priority" tag for fuel tanks: The priority number can't be greater than the number of tanks. For example, the Thunderbirds F-4E model only had one fuel tank defined, and it had a priority of 2, which resulted in it not feeding. One solution is to change the priority to 1. A better solution is to add the external tank definitions, as in the other F-4's. It's not necessary that the tank definitions in the FDM match the tank models actually installed on the model, so if the airplane might carry a certain external tank, go ahead and add the definition for it.

I'll be adding tank definitions for the external tanks that N-SCOT made for the A-7E , even though they aren't installed on my current A-7E model.

Monday, November 2, 2009

New F-4E

The F-4E is now set up so that the drag 'chute should be visible over multiplayer. As soon as I get a chance to test this online with someone I'll add this to all the models with drag 'chutes.

I also switched the weapons release key from 'space' to 'e'. While testing this I saw that some of the bombs appeared to impact each other after being released. I'd rather not increase the bomb release interval in an attempt to fix this, so we may be stuck with this for a while.

I had previously used the 'e' key for 'eject' in the OV-10 model, so I'll now need to look for another 'eject' key. Maybe 'F1'?

New DavePack

User "jano" found a bug in DavePack, another leading slash bug, so I've fixed that. I also fixed the wingtip vortices so they stop emitting when the airplane is crashed. In this case "crashed" means the JSBSim system called crash-detect has detected a crash.

I've also tried to standardize the usage of generic multiplayer properties in my models. Here's what I have so far:

float[0] - rotating beacon 1
float[1] - rotating beacon 2
float[2] - nose (tail) wheel steering angle
float[6] - drag 'chute unfurl

int[0] - tail numbers
int[3] - gun smoke
int[4] - wingtip vortices
int[5] - contrails
int[6] - drag 'chute deploy
int[7] - smoke
int[10] - afterburner plume, engine[0]
int[11] - afterburner plume, engine[1]

Soon I hope to have all the models meet this standard.

Sunday, November 1, 2009

Starting a turbine

I made a recent change to the turbine code that allows you to abort a start properly. With this change the default FlightGear key binding for the 's' key won't work for turbine engines. I'll be adding a new binding definition for the 's' key to all my turbine-powered models. The new binding is a simple toggle, which sets the starter valve to true (open) or false (closed).

The procedure for starting the turbines is: 1) make sure the cutoff property is true (it should be by default), 2) set the starter property to true, 3) when N2 reaches at least 15% place the cutoff property to false. The turbine will accelerate to idle and the starter will automatically set itself to false.

Wednesday, October 28, 2009

Piston airplane progress

Well, I'm learning how to make piston powered airplanes as I go along. The Skyraiders and the TigerCat are my experiments. The engines appear to do what they ought to now, and I've added instruments for rpm, manifold pressure and fuel flow, that I'll put in all the piston airplanes. Engine sounds are still a work in progress.

The propeller needs some higher pitch settings. A couple years ago I made an improved propeller builder for AeroMatic, but it's still under a pile of papers around here somewhere. It has the data to extend the propeller table to 55 degrees of pitch, which is what the warbirds need.

A new AD-4 is posted now, and F7F version 1.3 (I skipped 1.2) is posted. Let me know about bugs and any suggestions! BTW, both these airplanes now use the 'e' key to fire weapons.

Tuesday, October 27, 2009

F7F update

Right after I released version one of the F7F I found that it wouldn't climb above about 9200 feet. Ron Jensen recommended an auto-mixture controller, and this did the trick! Adding the auto-mixture system required changing the binding for the 'Shift-Q' key, which now shuts the engines down by turning the magnetos off/on.

Version 1.1 is posted now.

F7F release 1.0

Version 1.0 of the Tigercat is now posted at the hangar. This is a single seat, Marine Corps F7F-3 fighter-bomber. The nose guns have been removed, which I've read was a common field modification. There are 11 weapons stations, with number 6 being the centerline station. The 'e' key drops/fires weapons.

I'm still hoping to make the piston engine sounds better some day. This airplane has no unit markings because I haven't found ones I like that would be right for this airplane. I also need to make manifold pressure and rpm gauges.

Tuesday, October 20, 2009

Future Projects

Someday I hope to get to these two. An F8F and F9F. Maybe I can fill a carrier with dark blue USN airplanes some day.

Piston engine sound

The F7F model is using some experimental sounds. I'm trying to come up with a set of piston sounds for starting, idling, running, and shutdown that sound good. Once I get the sounds right I can make these standard for the piston powered airplanes in the hangar. The jets share a set of sounds already. If anyone would like to experiment and finds a sound config that seems right, please let me know.

Friday, October 16, 2009

A-3 Skywarrior

The Skywarrior is now at release 1.0. I was thinking of making the tail guns fire, but on second thought it seems rather pointless unless they can aim at something. An aiming system can probably be cooked up in nasal, wherein it will shoot at the nearest AI/MP model that gets within range. In the future I'd like to have it drop a bomb (a nuke?). Anybody want to model a nuclear explosion? If not, then it can always serve as a supply or utility airplane.

Thursday, October 15, 2009

Skies Over Hanoi

"TheAok1" has posted a nice video at YouTube showing MiG-21 vs. F-4 action. How did that Japanese guy get in there :)

Wednesday, October 14, 2009

F-7F Tigercat

Just started this one. It should make a nice carrier airplane. Looks like it only came in dark blue :)

Trigger key

I'm planning on converting all my airplanes to use the "e" key for a trigger. I'm doing this because FGCOM seems to be getting popular, and it uses the space bar. Let me know if you think a different key would be better, or if I should keep using the space bar.

Wednesday, October 7, 2009

AD-4 / DavePack updates

New DavePack is available with 2 new types of bombs, the M57 and M64 GP bombs of 1940's-1960's vintage. These were later replaced by the Mk-80 series of bombs in the 1960's. I added these for the AD-4, which now has a centerline fuel tank, two M64's, four M57's, and eight rockets. The rockets fire now.

The hold back on getting those to fire is the problem of how to make them work with the wing folding. In order for any wing ordnance to fold along with the wings the ordnance must be part of the airplane model, rather than being imported from DavePack. The stores on the non-folding parts of the airplane can be imported from DavePack.

My plan for the AD-6 is to arm it with eight rockets, two rocket pods, two Mk-82 on the wings, two wing fuel tanks, and a Mk-82 on the centerline.

Tuesday, October 6, 2009

Hangar Overhaul

Just updated DavePack and most of the airplanes in the hangar to include: "pick" animations, prioritized fuel burn, and new fuel gauges. Most of the new gauges will read zero if you're using FlightGear 1.9. As soon as the next release comes out the gauges will read properly again.

Monday, October 5, 2009

AD-6 Skyraider

First cut at the AD-6 project is now up. This is a livery for VA-145 "Swordsman". The time frame is about 1970, cruising aboard the USS Ranger, CVA-61. All three Skyraiders need more model work, including lots of animations.

Saturday, October 3, 2009

AD-4 Skyraider

FlightGear user "Bravo" has created a new livery for the Skyraider, based on the Korean War era colors worn by the Fighter Factory AD-4. I've posted it at the hangar in the projects section. I'll be developing this one in parallel with the A-1H, and probably also with an AD-6 version, which will have a Vietnam era gray paint job.

Friday, September 25, 2009

F-82 and C.205

Just started two projects, a North American F-82 Twin Mustang, and a Maachi C.205 Veltro. Both are conversions from models I found at sim-outhouse.

Wednesday, September 16, 2009

Fuel system

Posted at the jsbsim-devel list is a message about proposed changes to the fuel feed system, allowing you to define the feed sequence at load-time, and to adjust it at run-time. I could use some more testing before I commit it, so if you need something to do you can grab the files here.

For example, with the F-4J you can give the internal fuel tank a priority number of 2, while the external tanks have a priority number of 1 (the default). This will cause the external fuel to be burned first, then internal fuel next.

Tuesday, September 15, 2009

New F-4N update

Nic Quijano, who BTW has started his own FlightGear-related blog, has added selectable armament loads to the F-4N, so you now have a choice between the original air defense load with three drop tanks and a new CAS (Close Air Support) load with six Mk 82 bombs. The original load is invoked by running the original "F-4N-set.xml" model, while the new one is invoked by running "F-4N-CAS-set.xml". This brings the F-4N version number up to 3.1.

Nic also tied the fuel gauge to the total fuel. I'm still torn on what I want to do hangar-wide concerning this. Probably best to convert all the models over, then when the next FlightGear version is released I can switch some of the fuel gauges back to tank[0] if I want.

Thanks for the nice work Nic!

Friday, September 11, 2009


Over at sim-outhouse.com they've uploaded a lot of new freeware CFS2 aircraft models. Many of these can be converted for use in FlightGear. Because I just read a book on P-47 operations in WWII, I downloaded a P-47N model and started the conversion process. I have it flyable (barely) now, borrowing heavily from the Skyraider model, but it still needs a lot of work. Anyone looking for a project? This one would go onto a back burner here, and it may be a long time before I can get back to it.

Wednesday, September 9, 2009

Modeling How To

There is already a nice HowTo available in FlightGear's data/Docs directory, but here are some screenshots I took of the process. First, a screenie of AC3D showing normal working view. Note that the model should be built in the orientation shown, and not in the orientation suggested by the names of the panes (AC3D's coordinate system is not the same as FlightGear's). Then a screenie of an untextured mesh. Then a screenie of the texturing process, showing how a projection of parts of the mesh are matched to a texture. Finally, a screenie of the textured model.

Tutorial available

I've made available a sort of "beginners guide to FlightGear models" at the URL: http://home.comcast.net/~davidculp2/hangar/tutorial.html
It just explains what files are found in my model directories. There is a lot of leeway as to how you want to arrange your files within a model directory, so keep in mind that this is just the way I've settled on.

Saturday, September 5, 2009

Further Skyraider updates

Added wing fold animation, but not the aerodynamic effect yet. Added armament system as on the A-29B model. See aircraft help menu for details. You have bombs on stations 7, 8 and 9, and Zuni rocket pods on stations 5, 6, 10 and 11. Weapons are fired symmetrically, so firing stations 1-7 will also fire the symmetrical stations (9-15) on the right side.

Added flap animation, and further propeller animation. Also, "shift-Q" now toggles the mixture control. Mixture is already set to 1 (rich) at startup. Setting mixture to 0 will kill the engine.

Many thanks to Ron Jensen for making an R-3350 engine for me.

Friday, September 4, 2009

Gary's newest Phantom livery

Gary "N-SCOT" Brown has made another Phantom model, this one with a 1976 American Bi-Centennial theme. This sharp-looking bird is available at his hangar.

Skyraider update

I've done some work on the A-1H Skyraider model, but much more work remains to be done. It now has propeller animation, landing gear de-selection (the first step in gear animation), and a working tail hook. No instruments yet, but using a HUD you can do carrier traps, even though it has an Air Force paint job :)

The engine is a 2700hp electric motor. Some day I'll figure out the new piston code and make a piston engine for it. The propeller gives it some torque (the wrong direction though?) that makes it a challenge to fly. You can't just trim it up and let go of the stick, well, unless you add useful bindings for aileron and rudder trim.

Sunday, August 30, 2009


I've posted a newer F-5E model. Still no cockpit, and lots more animating and painting to go. I did put a hook on it, and "someguy" and I have been trying to do carrier traps with it, with about a 15% success rate. Oh well, it wasn't meant for carrier ops anyway. Like most Air Force airplanes the hook was only meant for use in catching a departure-end cable. I'll be checking it against the BAK-12, and if it catches that (departure-end) OK then I'll consider the hook done. Also, as someguy noticed, the yaw damper needs to be turned up a bit, or the base yaw stability derivative needs to be increased a bit. Either way.

Saturday, August 29, 2009

VX-4 paint for the F-4J

Gary Brown has released a repaint of the F-4J in the colors of Navy Squadron VX-4, "The Evaluators". The squadron was known for their use of the Playboy bunny logo on their airplanes. You can fetch the repainted F-4J at Gary's hangar.

Tuesday, August 25, 2009

Douglas A-4E Skyhawk

I just started a conversion of a Denis and Daniel da Silva model of the Douglas A-4E Skyhawk. It may be a long time before I can get to it. Is anyone looking for a project? A screenshot of the model as shown in AC3D is posted at the Hangar.

Sunday, August 23, 2009

Over G

Some of the Hangar models have an over-g handling system that will cause the model to freeze in position if the airplane is over-g'd. You can regain control by pushing the stick forward. I haven't added this system to all the models because I'm not sure if users will find it desirable, and I'd like feedback on this. Like all systems, you can turn it off by removing the line that activates it from the JSBSim configuration file.

Friday, August 21, 2009

Gun Effects

Last I checked there is no default key or button binding in FlightGear for a trigger, so you have to define your own. I use the trigger on my joystick, which is the most obvious choice. Just modify your joystick configuration to bind the trigger to the property "/controls/armament/trigger". While you're there I recommend binding the "hat" fore/aft axis to "/controls/flight/elevator-trim", which is how a real aircraft stick works anyway.

Thursday, August 20, 2009

Nice video of F-4N and Nimitz

"TheFGBlaze" has just posted a nice video of the F-4N model and the carrier Nimitz in FlightGear.

Wednesday, August 19, 2009

DavePack bug fix

"Jano" discovered a leading-slash bug in DavePack, so this has been fixed now. Thanks Jano! The leading-slash was causing the user's afterburner effect to also appear on other multiplayer airplanes. I also had to include a new JSBSim system, called "ab_workaround", that works around a multiplayer limitation, namely that the afterburner state is not sent over the multiplayer protocol. So far only the F-4J and F-4N have been converted, and I could use some testers. Please let me know if the afterburner animations of these two aircraft work properly over multiplayer.

Monday, August 17, 2009

The AOA lights

Some time in the 1950's the Navy, and later the Air Force, started putting AOA annunciator lights on top of the instrument panel to aid in holding proper angle of attack for landing. The top light tells you your AOA is too low (fast), the middle light tells you you're right on, and the bottom light tells you your AOA is to high (slow). The funny thing is the Navy and Air Force couldn't agree on what colors of light should mean what, so they ended up using different schemes. In the Navy scheme the light colors from top to bottom are green, yellow, red. In the Air force scheme they are yellow, green, red. So, in a Navy jet you want to see a yellow circle displayed while on final approach, and in an Air Force jet you want to see a green circle.

Vigilante Trivia

Did you know the RA-5 Vigilante, shown above in the title graphic, had no rudder, no ailerons, and no elevators? You can amaze your friends with this one! Actually it's a bit of a cheat. Instead of a rudder the entire vertical stabilizer rotated about a point. Same for the horizontal stabilizers, sometimes called "slabs". Instead of elevators the whole slab rotated about a point, which is standard procedure now in supersonic fighters. Instead of ailerons the Vigi used spoilers, with some differential slab movement mixed in. All in all this setup was pretty advanced for the times.

Aerial Refueling

Many of the models have refueling switches. These switches extend the refueling probe (or open the refueling door) and begin the refueling process. A green light on the fuel gauge lets you know that refueling has begun. My airplanes used to honor the air refueling "box" behind the tanker, so that you had to be in position there to refuel. Someone changed this in FlightGear, requiring refuelers to have a nasal script installed in order to honor the box. I've decided not to support this change, so my models can now refuel anywhere. Sorry about that.

Saturday, August 15, 2009

Adverse Yaw

If you've flown the F-100D model from the hangar, and flown it hard, you'll notice that adverse yaw is included in the flight dynamics model. Most swept wing jets of this era had an adverse yaw problem, even though designers tried to lessen the effect by using spoilers for roll control, or by combining spoilers and ailerons. At high angles of attack (AOA) the pilot needed to limit aileron deflection and use rudder instead to roll the airplane. The F-100D model needs to be flown like this, which means flying at high AOA will be very difficult for you unless you have a handy way to control the rudder. For most of us that would be accomplished by using the "twist grip" feature of a computer joystick. Some of you may have actual rudder pedals to use as input (the ultimate solution), and some of you are stuck using the keyboard or mouse.

So, here's my dilemma. I want to add adverse yaw to my most popular models, the F-4 Phantoms, however this will cause some current users to stop using the models when they find it difficult, if not impossible, to fly at high AOA. My inclination is to go ahead and do it, using the reasoning that users who want to avoid the expense of a joystick are asking too much of the simulation to adapt to them.

What do you think?

Chengdu F-7

I've posted the Chengdu F-7 as a new project. It's a Chinese derivation of the venerable MiG-21, with a Chinese built engine, a new double-delta wing, and upgraded avionics. The model represents the airplane used by the "August First" or "8.1" aerial demonstration team. As such there is a working smoke generator, activated by the "shift-S" key combination.

Remaining work to be done: wheel wells, canopy. I might add a centerline "travel pod", as I've seen these in many photos of the airplane, but I'm not sure if they carry these during the show or just when traveling between shows.

The texture is pretty, but could use some work as well. The fuselage is texture-mapped left/right, which makes it difficult to get a sharp edge where the blue areas angle together at the top and bottom of the fuselage. Mapping top/bottom would cause the same problem to appear at the left/right edges. I was able to solve this problem in the Thunderbirds F-4E model by exaggerating the angle of the paint edge as it approaches the texture's edge.


Welcome to the Dave's Hangar blog. I've set the blog up in order to announce updates to Dave's Hangar. If the comments feature works well I can also use this blog to answer questions, or host discussions on what Dave's Hangar users would like to see in the models. I'm on the road a lot, so this might be a convenient way to stay connected. As always, I can be reached at my POP3 email account at the address shown at the top of Dave's Hangar, or at the Facebook group on FlightGear, or at the JSBSim developer's email list. I lurk at the FlightGear forum, and the FlightGear users and developers email lists. I sometimes log into the #fg_cantene channel at irc.flightgear.org.