DoughBree L-39C (FSX)

[DaveB]

Hi Bjoern

Yes.. you DO have to read the manual don't you! Having loaded it up first and planning to **** IDC, I found FSX starting with an ini error. This was corrected by reading the manual and finding a folder that needed to be put in the Gauges folder!

Just a couple of things..
I keep getting a red Cabin Press warning even though the ECS is on and the lever reads pressurized. Turning the ECS lever off then back on clears the Cabin Press warning lamp. From what I can tell.. 'normal' flight doesn't force the warning lamp but doing aero's does. It's not a problem in the grand scale of things.

I've increased the aileron response a little and the elevator response by a smaller degree.. the aileron as I felt the roll-rate as a bit slow and the elevator to help it pull loops a bit easier. The elevator probably wouldn't need touching if the model was a bit faster. Having found and read a pilots report.. it's supposed to be able to pull a 4G loop in around 4000ft with an entry speed of 320kts+. The 320kts+ is eluding me hence a slight increase in elevator response.

All minor stuff really. It's still an immense amount of fun and thanks again for all your effort

ATB
DaveB

 

[Daube]

Guys, while you are working with the textures, has anybody tried to produce some bumpmapping ?
The freeware L-159 has some great bumpmapping on the wings, which produces quite a nice metallic/fresh paint visual effect with the sun reflections:

 

[Bjoern]

Here you go...

Authentic colours for SEA ...with a civie reg .

I probably need a break from this one paintkit too....chasing the 'yellow' trim around the canopy is always a killa ...

Thanks!

By the way: Are you doing the textures from the ground up?
If so, do you want/need bump map support?

Yes.. you DO have to read the manual don't you! Having loaded it up first and planning to **** IDC, I found FSX starting with an ini error. This was corrected by reading the manual and finding a folder that needed to be put in the Gauges folder!

Told you that you need to ****.

I keep getting a red Cabin Press warning even though the ECS is on and the lever reads pressurized. Turning the ECS lever off then back on clears the Cabin Press warning lamp. From what I can tell.. 'normal' flight doesn't force the warning lamp but doing aero's does. It's not a problem in the grand scale of things.

As specified in the manual's ECS and Electrical System chapters needs 115V AC from INV I or II.
Switch on either inverter, then switch the ECS off and on.

If you get the light in-flight, the controller can't keep up with your climb speed.

I've increased the aileron response a little and the elevator response by a smaller degree.. the aileron as I felt the roll-rate as a bit slow and the elevator to help it pull loops a bit easier. The elevator probably wouldn't need touching if the model was a bit faster. Having found and read a pilots report.. it's supposed to be able to pull a 4G loop in around 4000ft with an entry speed of 320kts+. The 320kts+ is eluding me hence a slight increase in elevator response.

I haven't touched the FDE at all. What values did you set aileron and elevator effectiveness to?

Drag seems to be a bit of an issue for this model, but without any drag polars or hard data, I can't (and won't) touch it.

Guys, while you are working with the textures, has anybody tried to produce some bumpmapping ?
The freeware L-159 has some great bumpmapping on the wings, which produces quite a nice metallic/fresh paint visual effect with the sun reflections:

There is no bump map support and I can live without them. I'll leave the decision up to Jafo, as he's contributing paints.

 

[DaveB]

Hi Bjoern

Yes.. I had the INV switched on. If you don't.. you get a warning lamp. I had them both on As I mentioned, straight/level flight isn't a problem nor are light manoeuvres.

I didn't have any technical reference for my changed settings. Watching solo displays of the L39, it has a nice crisp roll-rate so for a shot in the dark.. I changed the aileron effectiveness value from 1 to 1.5. This livens it up without turning it into an F-18. The elevator was changed from 1 to 1.3.

Drag is a bit of an issue as you say. It's impossible to get an overspeed in level flight! I guess this isn't surprising as the model was initially FS9 as drag values changed between FS9 and FSX as they did between FS8 and FS9. I can understand you not touching it either as this opens another can of worms!!

As I said though.. it's still a lot of fun and these things don't spoil it in any way. A little more speed or a little less drag would be nice but I can live without either
ATB
DaveB

 

[Bjoern]

*Sigh*
I just can't help it. Assigning autopilot functions to the last few empty switches ATM.

As I mentioned, straight/level flight isn't a problem nor are light manoeuvres.

Do some climbs/decents and watch the differential indicator. The limit for the light is -0.4 and +4 psi. From 6500ft upward, the controller will increase the differential cabin pressure to 3.55 psi, so that's a crucial point.
I might need to ramp up some proportional values for the pressure controller.

I didn't have any technical reference for my changed settings. Watching solo displays of the L39, it has a nice crisp roll-rate so for a shot in the dark.. I changed the aileron effectiveness value from 1 to 1.5. This livens it up without turning it into an F-18. The elevator was changed from 1 to 1.3.

I might give these a try and put them into the aircraft.cfg.

Drag is a bit of an issue as you say. It's impossible to get an overspeed in level flight! I guess this isn't surprising as the model was initially FS9 as drag values changed between FS9 and FSX as they did between FS8 and FS9. I can understand you not touching it either as this opens another can of worms!!

Well, provided that the engine performance is correct, playing around with drag is just half a can of worms. The engine tables in the .air file look a bit dubious though...

The manual suggests an entry speed of 600 km/h for aerobatics. At 4000ft, I can barely manage 500 km/h.
And then again, the maximum speed of the L-39C is 780 km/h or so...

 

[gray eagle]

Okay, the engine is started and when I give full throttle, it rolls forward a few feet then stops. Yes. the brakes are off.

 

[falcon409]

Okay, the engine is started and when I give full throttle, it rolls forward a few feet then stops. Yes. the brakes are off.

Your throttle is locked, near the base of the throttle handle is a click spot, it will unlock the throttle.

 

[DaveB]

I DID advise that you really DO have to ****

ATB
DaveB

 

[gray eagle]

I installed the older version and it worked great. Guess I'll try this one (Again)

 

[Bjoern]

Hm. ISA conditions plus EGT limiter yield 305 KIAS or 550-ish km/h at 4500ft. 315 KIAS if I override the fuel governor, but stay just shy of 700°C.

Your throttle is locked, near the base of the throttle handle is a click spot, it will unlock the throttle.

With the throttle lock engaged, he shouldn't be able to start the engine. Or does CTRL+E work?

Okay, the engine is started and when I give full throttle, it rolls forward a few feet then stops. Yes. the brakes are off.

*Ahem* RT(F)M, especially the "Operational Notes" page.

 

[gray eagle]

I DID advise that you really DO have to ****

ATB
DaveB

You did, but I did not read it like it were a NATOPS manual and that I was going to get a certification quiz afterwards.

 

[Bjoern]

Wow, I've managed to smooth out the fuel governor code so much that I get maximum possible engine performance below the EGT treshhold without a notable amount of twitching.
(You guys should have seen the code I've used before yesterday's revamp. "Fighting the airplane" all the way!)

You did, but I did not read it like it were a NATOPS manual and that I was going to get a certification quiz afterwards.

Don't give me ideas...

 

[gray eagle]

Wow, I've managed to smooth out the fuel governor code so much that I get maximum possible engine performance below the EGT treshhold without a notable amount of twitching.
(You guys should have seen the code I've used before yesterday's revamp. "Fighting the airplane" all the way!)





Don't give me ideas...

FYI....It does start with CTRL + E
I read the install info, "this goes here and that goes there", and managed to pull that off
After that, I glanced thru the pages of mandates on the button and switch flipping and was a bit intimidated by it all.

 

[DaveB]

hahahahaha...

I have to admit that **** is generally a 'last resort'. I found the throttle locked too which despite Ctrl+E.. still has you going nowhere. I looked all over the place for the lock and kept missing it with the mouse so the manual had to be consulted. When I saw where it was, I couldn't believe I'd missed it with the mouse!

Your revised fuel governor code sounds interesting. I'm all in favour of maximum oomph with the minimum of flames!! The way the engine spools up seems ok at the moment. These things are notoriously slow to spool and the current settings fit well. One thing I read in that pilots report was that pilots with little experience on the type will often drop the airbrakes on approach thus requiring more throttle and thus.. keeping the RPM higher to reduce the spool up time should things go wrong. Once 'au fait' with the type.. this practice is dropped. I'd love a go in a real one

ATB
DaveB

 

[Bjoern]

Autopilot is in. Need to see if I can do something about the drag.

After that, I glanced thru the pages of mandates on the button and switch flipping and was a bit intimidated by it all.

Just get acquainted with the startup and read up on the rest when you need it or something breaks.

hahahahaha...

I have to admit that **** is generally a 'last resort'. I found the throttle locked too which despite Ctrl+E.. still has you going nowhere. I looked all over the place for the lock and kept missing it with the mouse so the manual had to be consulted. When I saw where it was, I couldn't believe I'd missed it with the mouse!

Guess what happened to me when I tried to start the engine today...
"This can't be a bug! My code is perfect! What does the manual say about thi-THROTTLE LOCK!"

One thing I read in that pilots report was that pilots with little experience on the type will often drop the airbrakes on approach thus requiring more throttle and thus.. keeping the RPM higher to reduce the spool up time should things go wrong. Once 'au fait' with the type.. this practice is dropped. I'd love a go in a real one

Check the reports for info on whether they fly their L-39s with tip tanks or without. These things - even if empty - do add a bit of drag and inertia.

 

[DaveB]

I'll keep an eye out for anything specifically dealing with 39's without tip tanks I found that pilots report I mentioned.. http://www.warbirdalley.com/articles/l39pr.htm

EDIT: Looking through the images available on the web, the number of 39C's without tip tanks can be counted on the fingers of one hand. I think it's likely that the report above is in an aircraft with tip tanks

ATB
DaveB

 

[Bjoern]

I've added a tooltip to the gauge glass for various readouts, like imperial speed and accurate EGT temps.

I'll keep an eye out for anything specifically dealing with 39's without tip tanks I found that pilots report I mentioned.. http://www.warbirdalley.com/articles/l39pr.htm

EDIT: Looking through the images available on the web, the number of 39C's without tip tanks can be counted on the fingers of one hand. I think it's likely that the report above is in an aircraft with tip tanks

Looks like a tip tank model in the PIREP.

Here's one flying without tips (not the one having the camera):
http://youtu.be/foAywOStED0

Anyway, I've decreased induced drag by 10% and parasitic drag by 5%. Riding the limiter at 4000 ft at ISA yields 330 KIAS or just shy of 600 kph.

The cabin pressure controller kept up with a 5000ft zoom climb and a loop. It was only with a 6000+ fpm descent that I could make the warning light illuminate.

 

[Jafo]

Thanks!

By the way: Are you doing the textures from the ground up?
If so, do you want/need bump map support?


There is no bump map support and I can live without them. I'll leave the decision up to Jafo, as he's contributing paints.

Essentially from the ground up...as I started from the paintkit adding 'doubled' existing paints [1024 to 2048] which result in even fuzzier details than the original 1024 so they are redefined. Also the originals have shadow 'painting' which isn't needed with your FSX model so the paints are done 'flat' [mostly].
The T'Bird and Qantas are originals. The SEA is 99% original - working from an existing camo 'pattern'.
You can sort of 'fake' bump mapping which is sometimes better than the real thing - when the latter is too fat/prominent/out of scale.....which is what I've been doing, so I can live without them too.

The existing paints are fine in FSX [ignoring the shadows] so I've been playing more with 'what-ifs', but my fiddling with the paintkit means it's relatively simple for me [now] to do just about any a/c paint for it.

If I could just work out how to shrink my psp file to something more sane I'd upload it too. Currently fuse_t.psp is 571 meg.


If anything was to be added to the model visually then rather than bumps I'd prefer underwing stores, gun pod, etc...

 

[DaveB]

I've added a tooltip to the gauge glass for various readouts, like imperial speed and accurate EGT temps.





Looks like a tip tank model in the PIREP.

Here's one flying without tips (not the one having the camera):
http://youtu.be/foAywOStED0

Anyway, I've decreased induced drag by 10% and parasitic drag by 5%. Riding the limiter at 4000 ft at ISA yields 330 KIAS or just shy of 600 kph.

The cabin pressure controller kept up with a 5000ft zoom climb and a loop. It was only with a 6000+ fpm descent that I could make the warning light illuminate.

Rgr that mate Looking forward to trying the mods

ATB
DaveB

 

[Bjoern]

If I could just work out how to shrink my psp file to something more sane I'd upload it too. Currently fuse_t.psp is 571 meg.

YIKES! Tried to consolidate as many layers as possible...?

(GIMP is much better at compressing image files. Can turn a 400 MB .psd into a ~20 MB .xcf.

If anything was to be added to the model visually then rather than bumps I'd prefer underwing stores, gun pod, etc...

The -C has provisions two hardpoints. Adding these with drop tanks attached to them is somewhere on the "To Do" list.
Another idea is turning the model into the -V target tug, but that requires a bit more work.

There's not really a chance for a -ZA or -ZO. Next to having to model a whole range of weapons, I'd also have to deal with the gunsight, stores management and the TacPack crowd that would inevitably come whining about if and when there will be support for it.
Besides, there already is a -ZA, courtesy of Hadi Tahir. It even comes with a working rear cockpit!

Rgr that mate

Looking forward to trying the mods

Currently doing a bit more tweaking.