Board index FlightGear Development Aircraft

DHC-6 Twin Otter development

Questions and discussion about creating aircraft. Flight dynamics, 3d models, cockpits, systems, animation, textures.

Re: DHC-6 Twin Otter development

Postby SurferTim » Sat Mar 30, 2019 4:52 pm

wlbragg wrote in Sat Mar 30, 2019 4:47 pm:@SurferTim it would be really appreciated by the community if you made these fixes and upgrades available to the community.

I will as soon as I get this version where it is meeting my satisfaction. I'm flying it around the Caribbean now to test it.
Fly low, fly slow, land on a dime. Twin Otter DHC6-300+. https://github.com/SurferTim/dhc6p
PirateAir videos at https://www.youtube.com/user/SurferTim850
User avatar
SurferTim
 
Posts: 924
Joined: Sun Dec 09, 2018 5:49 pm
Location: Miramar Beach, FL
Callsign: Pirate
Version: 2019.2.0
OS: Ubuntu 18.04

Re: DHC-6 Twin Otter development

Postby SurferTim » Sun Mar 31, 2019 12:58 am

You can try what I have so far.
http://www.prolectron.com/flightgear/dhc6st.zip

Corrected reverse thrust bug. Very apparent with Saitek/Logitech throttle quadrant.
Corrected engine sound. Prop rpm varies pitch, throttle varies volume.
Corrected instrument lighting for night flight. Still needs a little work.
Corrected parking brake default to set when autostart.
Added ALS landing and taxi lights. Could use a bit more work.
Added PirateAir livery.

Any other bugs/suggestions/ideas?
Fly low, fly slow, land on a dime. Twin Otter DHC6-300+. https://github.com/SurferTim/dhc6p
PirateAir videos at https://www.youtube.com/user/SurferTim850
User avatar
SurferTim
 
Posts: 924
Joined: Sun Dec 09, 2018 5:49 pm
Location: Miramar Beach, FL
Callsign: Pirate
Version: 2019.2.0
OS: Ubuntu 18.04

Re: DHC-6 Twin Otter development

Postby tdammers » Mon Apr 01, 2019 8:56 am

Would you mind putting it on a git repo somewhere?
tdammers
 
Posts: 293
Joined: Wed Dec 13, 2017 10:35 am
Callsign: NL256
IRC name: nl256

Re: DHC-6 Twin Otter development

Postby SurferTim » Mon Apr 01, 2019 10:54 am

tdammers wrote in Mon Apr 01, 2019 8:56 am:Would you mind putting it on a git repo somewhere?

Would you be more comfortable with the code on Github?
Fly low, fly slow, land on a dime. Twin Otter DHC6-300+. https://github.com/SurferTim/dhc6p
PirateAir videos at https://www.youtube.com/user/SurferTim850
User avatar
SurferTim
 
Posts: 924
Joined: Sun Dec 09, 2018 5:49 pm
Location: Miramar Beach, FL
Callsign: Pirate
Version: 2019.2.0
OS: Ubuntu 18.04

Re: DHC-6 Twin Otter development

Postby tdammers » Wed Apr 24, 2019 2:24 pm

SurferTim wrote in Mon Apr 01, 2019 10:54 am:
tdammers wrote in Mon Apr 01, 2019 8:56 am:Would you mind putting it on a git repo somewhere?

Would you be more comfortable with the code on Github?


Github would be great, but any git repo I can pull from works for me.
tdammers
 
Posts: 293
Joined: Wed Dec 13, 2017 10:35 am
Callsign: NL256
IRC name: nl256

Re: DHC-6 Twin Otter development

Postby msalama » Tue Jun 18, 2019 4:54 am

Hi all -

Just registered, a long time simmer here & pretty impressed how far FG has progressed in the ten years I've been absent. Kudos all! Anyway, I tried the Twotter and it's an excellent AC otherwise, but it seems there's no ground effect whatsover modelled. Is it just me, or is this how the plane behaves IRL too?

S!

M.
msalama
 
Posts: 36
Joined: Tue Jun 18, 2019 4:44 am

Re: DHC-6 Twin Otter development

Postby scarymovie » Wed Oct 30, 2019 4:38 am

SurferTim wrote in Sun Mar 31, 2019 12:58 am:You can try what I have so far.
http://www.prolectron.com/flightgear/dhc6st.zip

Corrected reverse thrust bug. Very apparent with Saitek/Logitech throttle quadrant.
Corrected engine sound. Prop rpm varies pitch, throttle varies volume.
Corrected instrument lighting for night flight. Still needs a little work.
Corrected parking brake default to set when autostart.
Added ALS landing and taxi lights. Could use a bit more work.
Added PirateAir livery.

Any other bugs/suggestions/ideas?


Hi SurferTim, Thank you so much for this. I realized that the sound of the engine still sounded like "full power" when I decreased the power.
scarymovie
 
Posts: 84
Joined: Wed Nov 21, 2007 2:34 pm

Re: DHC-6 Twin Otter development

Postby SurferTim » Wed Oct 30, 2019 7:44 am

scarymovie wrote in Wed Oct 30, 2019 4:38 am:
SurferTim wrote in Sun Mar 31, 2019 12:58 am:You can try what I have so far.
http://www.prolectron.com/flightgear/dhc6st.zip

Corrected reverse thrust bug. Very apparent with Saitek/Logitech throttle quadrant.
Corrected engine sound. Prop rpm varies pitch, throttle varies volume.
Corrected instrument lighting for night flight. Still needs a little work.
Corrected parking brake default to set when autostart.
Added ALS landing and taxi lights. Could use a bit more work.
Added PirateAir livery.

Any other bugs/suggestions/ideas?


Hi SurferTim, Thank you so much for this. I realized that the sound of the engine still sounded like "full power" when I decreased the power.

The "engine noise" is actually propeller noise. The volume of the sound should decrease when the throttle is reduced, but the pitch (frequency) changes with the prop speed. It took watching a few videos of Twin Otters landing at St Barth to figure this out.

I've done some other work to my version of the DHC6. I'll post the new aircraft file soon.
Fly low, fly slow, land on a dime. Twin Otter DHC6-300+. https://github.com/SurferTim/dhc6p
PirateAir videos at https://www.youtube.com/user/SurferTim850
User avatar
SurferTim
 
Posts: 924
Joined: Sun Dec 09, 2018 5:49 pm
Location: Miramar Beach, FL
Callsign: Pirate
Version: 2019.2.0
OS: Ubuntu 18.04

Re: DHC-6 Twin Otter development

Postby dg-505 » Mon Feb 24, 2020 2:14 pm

Hello,

just a short note to all Twin Otter fellows :wink:

there has been an update in the official FGAddon hangar which now includes the variant with new, even more powerful PT6A-34 engines.

Thanks to SurferTim for the work.

Hint: Newsletter updated

Cheers
Jonathan
A mile of road will take you a mile, but a mile of runway will take you everywhere.

DHC-6 Twin Otter development
User avatar
dg-505
 
Posts: 653
Joined: Mon Jun 02, 2014 2:36 pm
Location: Bonn, Germany
Callsign: dg-505
Version: next
OS: Ubuntu 18.04.4 LTS

Re: DHC-6 Twin Otter development

Postby SurferTim » Mon Feb 24, 2020 4:52 pm

Thanks! I hope some enjoy it as much as I do. Most of the work was done before I got it. Thanks to those who developed the basic aircraft.

Edit: I recommend activating real-time and advanced weather. That is what makes it a real challenge.
You better be on top of your game.
Fly low, fly slow, land on a dime. Twin Otter DHC6-300+. https://github.com/SurferTim/dhc6p
PirateAir videos at https://www.youtube.com/user/SurferTim850
User avatar
SurferTim
 
Posts: 924
Joined: Sun Dec 09, 2018 5:49 pm
Location: Miramar Beach, FL
Callsign: Pirate
Version: 2019.2.0
OS: Ubuntu 18.04

Re: DHC-6 Twin Otter development

Postby Oswald » Sun Mar 22, 2020 8:12 pm

Thanks to everyone for all development, you are doing.

I'd like to get to work with the Twotter and learn to use it for VA purposes. Could you give me an idea, which version is the more realistic one in terms of FDM, fuel and payload management?

Oswald
Oswald
 
Posts: 108
Joined: Sat Feb 20, 2016 11:29 pm

Re: DHC-6 Twin Otter development

Postby SurferTim » Sun Mar 22, 2020 8:33 pm

Oswald wrote in Sun Mar 22, 2020 8:12 pm:Thanks to everyone for all development, you are doing.

I'd like to get to work with the Twotter and learn to use it for VA purposes. Could you give me an idea, which version is the more realistic one in terms of FDM, fuel and payload management?

Oswald

I prefer the DHC6-300+. I spent a bit of time getting some malfunctioning equipment working.
Its engines respond a bit more realistic. They decelerate twice as fast as they accelerate, which is about right.
I've recorded some flights in it if you are interested.
https://www.youtube.com/user/SurferTim850
Fly low, fly slow, land on a dime. Twin Otter DHC6-300+. https://github.com/SurferTim/dhc6p
PirateAir videos at https://www.youtube.com/user/SurferTim850
User avatar
SurferTim
 
Posts: 924
Joined: Sun Dec 09, 2018 5:49 pm
Location: Miramar Beach, FL
Callsign: Pirate
Version: 2019.2.0
OS: Ubuntu 18.04

Re: DHC-6 Twin Otter development

Postby Oswald » Tue Mar 24, 2020 2:41 pm

First attempts (wheel variants): DHC-6-300 YASIM works fine, JSBSim make my PC freeze after a few minutes, repeatedly, DHC-6-300+ works fine.

Your videos, Tim, show excellent take off and landing behaviour, though I don't see longer cruise periods. In my first tests the maximum and economy cruise behaviour of 300 or 300+ don't seem to be much different, I need more torque in the 300+ to maintain the same IAS (150 KIAS at 6000 ft), haven't looked at fuel consumption yet.
I haven't found cruise performance information for the DHC-6-400 (same engines as your 300+) compared to the DHC-6-300.

Is the power surplus for the 300+ meant to be for shorter take off and steeper climb, or should it be for faster cruise, too?

There is another issue that strikes me, quite similar to the Piper Aerostar (YASIM, too), and which is rather unfitting for VA use: changes in AP altitude or pitch setting are executed very abruptly, not as smooth, as one would wish for one's passengers. I also observed it in your videos. Is there anything to be done about it?

Oswald
Oswald
 
Posts: 108
Joined: Sat Feb 20, 2016 11:29 pm

Re: DHC-6 Twin Otter development

Postby SurferTim » Tue Mar 24, 2020 3:30 pm

Oswald wrote in Tue Mar 24, 2020 2:41 pm:First attempts (wheel variants): DHC-6-300 YASIM works fine, JSBSim make my PC freeze after a few minutes, repeatedly, DHC-6-300+ works fine.

Your videos, Tim, show excellent take off and landing behaviour, though I don't see longer cruise periods. In my first tests the maximum and economy cruise behaviour of 300 or 300+ don't seem to be much different, I need more torque in the 300+ to maintain the same IAS (150 KIAS at 6000 ft), haven't looked at fuel consumption yet.
I haven't found cruise performance information for the DHC-6-400 (same engines as your 300+) compared to the DHC-6-300.

Is the power surplus for the 300+ meant to be for shorter take off and steeper climb, or should it be for faster cruise, too?

There is another issue that strikes me, quite similar to the Piper Aerostar (YASIM, too), and which is rather unfitting for VA use: changes in AP altitude or pitch setting are executed very abruptly, not as smooth, as one would wish for one's passengers. I also observed it in your videos. Is there anything to be done about it?

Oswald

The behavior should be about the same. The engines spool down faster in the 300+, giving it a bit more realism when landing.
Also landing lights work, intake deflectors work. Radar altimeter has a voice alert.
The power surplus is for high altitude work. I cruise the Caribbean, and have yet to use full throttle. If you want to frequent airports like Lukla, the extra power will help.

Actually, the DHC-6-300+ AP transition is not quite as bad as the 300. I did dampen it out a little. It works best if you can get the a/c in level flight or near a zero rate of climb before engaging the AP.

Edit: I have some full flights that I streamed that show the 300+ in level flight and transitions. See the link to my YouTube page I posted above.
I highly recommend a yoke/joystick with throttle and pedals. I have a Saitek/Logitech yoke (fully moded with Bodnar fix. No deadzone. No detents), throttle quadrant, and pedals.
Fly low, fly slow, land on a dime. Twin Otter DHC6-300+. https://github.com/SurferTim/dhc6p
PirateAir videos at https://www.youtube.com/user/SurferTim850
User avatar
SurferTim
 
Posts: 924
Joined: Sun Dec 09, 2018 5:49 pm
Location: Miramar Beach, FL
Callsign: Pirate
Version: 2019.2.0
OS: Ubuntu 18.04

Re: DHC-6 Twin Otter development

Postby Oswald » Tue Mar 24, 2020 8:40 pm

Hi Tim, thanks a lot for your remarks, I'll dig further into the 300+ :)
Oswald
Oswald
 
Posts: 108
Joined: Sat Feb 20, 2016 11:29 pm

Previous

Return to Aircraft

Who is online

Users browsing this forum: Google [Bot], PK-DNZ_107 and 8 guests