L-39 Project Team

[Silver_Dragon 411]

http://forums.eagle.ru/showpost.php?p=1763587&postcount=246

 

**UPDATE**

 

Advanced Flight Model Aerodynamics Update

 

Work this week has been focused on a complete re-write of the AFM to change it over to a finite element model, where all control surfaces are broken into multiple parts (what I call Aerodynamic Sections), allowing more accurate airflow over each individual section.

 

How it Works

 

Each aerodynamic section defined in the FM has a set of properties that can be assigned to it, such as center of pressure, center of mass, chord length, local angle of attack, etc. These properties are unique to each section of the airframe, allowing different responses to maneuvers or damage. With each section of the wings and tail receiving different angles of attack during maneuvers, the forces automatically balance themselves when releasing the controls.

 

A list of some of the properties currently available:

Center of Pressure (x,y,z) //Defines lift location (can shift with mach and angle of attack)

Velocity Vector (x,y,z) //Calculated using rigid body kinematics (relative to aircraft cg)

Center of Mass (x,y,z) //Defines mass location

Lift Vector (x,y,z) //Unit vector defining lift direction

Drag Vector (x,y,z) //Unit vector defining drag direction

Position (x,y,z) //Used for storing position information (ex: variable geometry, gear postion, etc.)

Reynolds Number //Magic number used for my lift tables

Chord //Mean aerodynamic chord of section

Mach //Local mach number

Incidence //Local incidence angle

Dihedral //Local dihedral angle

Area //Aerodynamic section reference area

Mass //Mass of section allows for updates to aircraft balance if pieces are lost

Local AOA //Final effective angle of attack of section (incidence + velocity vector angle + other control surface effects)

Shadowing Factor //Used for reducing airflow over a surface being blocked by the fuselage

Damage Factor //Damage factor used to reduce lift/increase drag on a damaged surface

Attached Flag //Did you lose your surface completely?

 

How the aircraft was broken up:

Left and Right Wings broken into 10 sections total

Horizontal Tail broken into 4 sections total

Vertical Tail broken into 2 sections total

etc...

 

What this looks like (In Graph Form!):

L-39 in a maximum deflection roll!

[Silver_Dragon 411]

http://forums.eagle.ru/showpost.php?p=1767522&postcount=262

 

Testing the new EFM that we've re-written from the ground up in formation for the first time. Still some kinks to work out here and there, but the results so far are very close to the real deal. Exciting times ahead!

 

[Silver_Dragon 411]

 

Messing around with render techniques...I need to learn some better ones.

 

And beta can be to last 2013

https://www.facebook.com/TheVirtuals

 

It will be released as a full module for DCS. Stay tuned for more updates this year. Beta will not be ready until at least 4th quarter this year.

[Silver_Dragon 411]

L-39 update

 

http://forums.eagle.ru/showpost.php?p=1895195&postcount=370

 

*Quick Update*

 

A lot of work has been going on lately, but I don't always find the time to update this thread with everything I would want to say.

 

Collision Model

 

The collision model was recreated from scratch with animation and visibility arguments and was tied to the damage list.

 

Each section you see here will affect the flight model should damage or loss occur to the piece. If the right wing is lost, a quick left roll will begin due to asymmetric lift. If the horizontal tail is lost, pitch control will be lost and the aircraft may pitch violently up or down. If the vertical tail lost, directional control is lost. Each piece, even individual gear or wingtip tanks, cause their own drag. Losing a canopy will affect flight control and cause massive drag increases.

 

 

Random Failures

 

Work has begun on simulating random failures. While I have an idea how I want these to work, I won't go into details, yet. However, I know that I would like you guys to have more control over which types of failures you are likely to see during your training or combat flights. Because the L-39 is a trainer aircraft, it seemed fitting to allow more control of these settings. While the instructor pilot in the rear seat will be able to fail instruments and electrical systems manually, some things like mechanical, hydraulic, and engine failures cannot be simulated.

 

Failures only occur when the Random System Failures option is set on in the MISC options menu. While each individual pilot sets these options for their own flights, they are also saved to tracks and missions and forced on clients to ensure fair play and robust tracks.

 

Sliders for failure rates will operate as follows:

 

0% = No chance of occurring

1% = (1/100)X of Normal Rate

50% = Normal Rate

100% = 100X Normal Rate

 

Here is a snapshot of the current options menu:

 

 

As you can see, you can choose whether to include a rear seat pilot or not. While this will show a physical model of the rear pilot, it will also add 80kg to your weight. This option may go away when multi-seat capability is possible in multiplayer.

 

New Wingtip Options and Other Visual Options

 

Let's face it! Not every L-39 is created equal. There are so many variations even within the C civilian model, with some owners modifying their aircraft to reduce their weight by that last ounce, or squeeze a little more top speed out of the jet by changing wingtip types.

 

We have new wingtip types that can be set by the skin creator in the description lua file through arguments. These changes are not only visual, but also affect the weight and drag of the aircraft, even improving roll rate in some cases.

 

Options the skin creator has available:

L-39 Variant (C or ZA) This option is included in the skin creation as our C and ZA model share the same model and certain features are activated by this argument

Civilian Variant (Civilian, Aerobatic, Racer) C model can choose performance with this argument

Wingtip Type: Tanks, Sculpted, Curved Winglet, Double Winglet (Changing to another wingtip type will improve speed by about 25 km/h and lowers weight on the tips of the wing by 32 kg)

Rear Seat (Turning off the rear seat will make it visually disappear, but it will also save 85kg of weight)

 

Currently, we are only showing the sculpted wingtips:

 

 

There is a lot more development not mentioned here, but I thought this would keep you guys up to date.

__________________

[Skysurfer7 34]

Instant buy! as this is my all time favorite military jet in FSX.

[Silver_Dragon 411]

intersting L-39 update and the new Advanced Turbofan Engine Model (ATEM).

 

http://forums.eagle.ru/showpost.php?p=1960698&postcount=398

Time for a new year's update on the L-39. Work has been continuing, even without status updates to this topic, so no need to worry about this project being on hold.

 

Hydraulic System Implemented

Main and Emergency Hydraulic Circuits

Main Hydraulic Pump Pressurization from engine bleed air

Interconnect Valving and logic

Hydraulic pressure consumers: Gear, Gear Doors, Flaps, Ram Air Turbine, Wheel brakes, Speed brakes (main system only)

Emergency Extension Levers for Gear, Flaps, and Ram Air Turbine

Emergency Brake Lever

 

Miscellaneous

Random failures code was started, but has been put on hold for now

Fixed several major bugs (for ex: Engine would shut off during air starts)

 

Advanced Flight Model

Tweaks to Yaw Stability and Rudder Effectiveness

 

Advanced Turbofan Engine Model

I began work on this new fully dynamic engine model back in October, but it has not been implemented into the simulator at this point, so many things are still subject to change. However, I thought I would pass along some details about the planned features of this new turbofan engine model for the L-39. So far, I have written the entire engine model into a standalone program that runs at the same frequency as the DCS flight model and reads my throttle inputs in real time to simulate realistic dynamic conditions. I also view the output of the engine conditions in real time in several performance graphs.

Improved Thermodynamic Model that accounts for enthalpy changes across each subsection of the engine given inefficiencies and current dynamic conditions

Inertial Twin Spool Rotor Modeling

Aerodynamic blade drag for each compressor/turbine stage

Fuel Governor with a simple control algorithm to maintain sufficient fuel pressure at varying altitudes and airspeeds

Compressor/Turbine Efficiency Curves based on airflow and rotor speed

Two Anti-Surge Bleed Valves affect performance of the engine in the specified ranges for the L-39

Combustion efficiency dependent on Fuel/Air ratio

Air-starter Modeling of initial engine spool up

Light-off produces correct RPM acceleration and combustion allows for self-sustaining idle conditions

etc.

 

An example output from a slam acceleration/deceleration test in an early version of engine and fuel controller.

 

 

 

[HansRoaming 73]

Looking forward to this as is an excellent jet in FSX, just so much fun.

[Silver_Dragon 411]

https://www.facebook.com/TheVirtuals?ref=stream

 

EDGE model test.

 

Pics removed by L-39 Albatros Team requeriment

[Silver_Dragon 411]

new update:

 

http://forums.eagle.ru/showpost.php?p=2164265&postcount=40

A systems programming update:

 

Complete ADF radio simulation. This doesn't just include the wandering needle and general inaccuracy of the direction finding circuitry, but a COMPLETE simulation of the entire system. 

 

Complete list of features:

 

* Simulation of A1, A2 and A3 modulation of the ground station

* Highly accurate BFO tuning mode (yet another simulation first AFAIK)

* BFO mode ident (A1 modulation)

* Audio mode ident (A2 and A3 modulation)

* Accurate BFO tuning capability (characteristic hetrodyne when tuning)

* Sense and loop antennas modelled

* Comparator circuitry modelled, including simulation of cartoid signal pattern in loop antenna

* Automatic DF mode (comparator based)

* Accurate manual DF mode, including accurate signal peak simulation/nulls

* Stations can overlap and interfere with reception

* Accurate analog tuning - no digital on/off selection of the station

* Signal strength is affected by multiple conditions (range, altitude, weather conditions, time of day, accuracy of tuning)

* Coastal effect

* Night effect

* Weather (thunderstorm will cause needle to point away from station, and humidity can affect the signal)

* Static noises and clicks from simulated lightening strikes during thunderstorm

* Another cool feature that shall remain secret for now... 

* Manual and automatic mode for dual ADF approach (single radio/RBI, dual-head tuner)

* Complete simulation of auto mode for dual-ADF approach mode

 

Stay *ahem* tuned *ahem* ...

 

Best regards,

Tango.

 

 

[PWJT8D 446]

Holy moly! Do I need to get an amateur radio license to be eligible to purchase?

[Phantom88 3,287]

I'm very surprised ED/DCS is "Also" working on a L-39. Interesting News.

[Phantom88 3,287]

3rd Party L-39 Cancealled.....

http://forums.eagle.ru/showthread.php?p=2169482#post2169482

 

 

Regarding the announced cancellation of by Virtual Patriots of their L-39 project, there needs to be a few items clarified after the rather incomplete explanation provided by the Virtual Patriots team that painted an inaccurate picture:

Eagle Dynamics has had an L-39 in development for several years. However, we put it on the back-burner after we awarded the Virtual Patriots team a license to create their own. A very lengthy amount of time was awarded to them and we feel that it is now no longer sound to hold off on our internal L-39 any longer.

All third parties enter a license agreement with the full knowledge that they are not granted exclusive rights to develop the aircraft for DCS.

Over two weeks ago, the head of the Virtual Patriots team was informed of this decision and was supportive of it.

The Virtual Patriots L-39 license agreement was not cancelled. They are free to sell their project well before the Eagle Dynamics version. However, given the massive amount of work we still believe needs completed, we see that this would be difficult for them.

This was one of the first 3rd party license agreements we granted. Our requirements for licenses has changed drastically. This same project (even in its current state after two years), would not have passed current 3rd party project requirements to get a license now.

This is all that I and Eagle Dynamics have to say on the matter.

[Skysurfer7 34]

Glad it's still an ongoing project!