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big-mike
August 21st, 2014, 07:48
Bought her last week when she was on sale.
But even with throttles on idel this beast flies on with around 300knots.
Any idea?
Mike

Daube
August 21st, 2014, 08:43
I have exactely the same problem.
In fact, I flew that bird for a maximum of one hour since I bought it I think. It now stays in the hangar, I don't use it anymore :/
That's bad, because I really love the 3D model and the textures...

dhazelgrove
August 21st, 2014, 10:00
I'm assuming you've used the air brake?

I have the JF offering, and it's approaching nicely at just under 200 kts with the air brake popped.

Dave

JensOle
August 21st, 2014, 10:08
The jet engine thrust scalar is 1.20, most other jet fighters I have seen keeps it at 1.0. Maybe it can have something with the problem?

[jet_engine]
thrust_scalar = 1.2

Dev One
August 21st, 2014, 10:47
Sounds like a short cut too far in the FDE - especially if its payware!
Keith

big-mike
August 21st, 2014, 11:07
The jet engine thrust scalar is 1.20, most other jet fighters I have seen keeps it at 1.0. Maybe it can have something with the problem?

[jet_engine]
thrust_scalar = 1.2

Feels better now,but still overpowered.Speed stays with throttles at idle at around 220knots.
Mike

StormILM
August 21st, 2014, 18:38
I didn't buy the model while on sale even though I have wanted a decent Typhoon for some time. I have encountered this issue with different models that were both overpowered and underpowered and/or had too much or too little drag. The best way to fix them is by updating the airfile thrust and drag parameters but the quick & dirty way is by adjusting the thrust and drag settings in the config file. In this case(and not having hands on to test it), I would suggest lowering the thrust 1000 lbs at a time and if needed, make slight adjustments to the parasitic and induced drag scalars. As a rule of thumb on the thrust and drag, you should be able to turn at max G in afterburner and maintain constant airspeed (at optimum corner velocity) but be able to pull slightly more back pressure to increase drag and begin bleeding off speed and turning tighter while the G also bleeds off. It's a bit tricky to balance these parameters in FSX but it can be done. Worth a try!

big-mike
August 22nd, 2014, 07:51
Thanks for all your answers.
I changed some values,took them from another jet and itīs okay so far.
If someone has contact to Martyn from JF or to someone from AH,so please point them to this topic for a more "professionell" solution for all the Typhoon flyers.
Mike

Cleartheprop
August 22nd, 2014, 08:22
I have exactely the same problem.
In fact, I flew that bird for a maximum of one hour since I bought it I think. It now stays in the hangar, I don't use it anymore :/
That's bad, because I really love the 3D model and the textures...
Exactly the same symptoms here. Aircraft is more than overpowered. I guess some tweak in the air file would help but have no idea which line to edit ;)

Its a pity because the exterior model is quite beautiful.

odourboy
August 22nd, 2014, 08:48
I'm assuming you've used the air brake?

I have the JF offering, and it's approaching nicely at just under 200 kts with the air brake popped.

Dave

Agreed - in their manual JF recommends the use of the airbrake to reduce speed when lining up for your final. I don't know if this is 'standard procedure' or just a work-around suggested to compensate for a poor FDE design.

Cleartheprop
August 22nd, 2014, 11:41
Agreed - in their manual JF recommends the use of the airbrake to reduce speed when lining up for your final. I don't know if this is 'standard procedure' or just a work-around suggested to compensate for a poor FDE design.

Oh! Its not just a matter of being too fast on final.

Throttle idle, level flight, the airplane won't decelerate below 250 kts even after some time.

A very poor FDE programing indeed; It's too bad because it makes this add-on unusable especially for formation flying. Too bad.

odourboy
August 22nd, 2014, 12:15
A quick and dirty adjustment that gets it in the ballpark is to change the parasitic_drag parameter in the aircraft.cfg from 1.00 to 2.32. (this is for the JF Typhoon)

After this change, with a bit of energy management, I can do a decent final without the airbrake and achieve a maximum speed of 1.25 mach at sea level as per the spec. It will also eventually stall and crash with idle throttle.

Cleartheprop
August 22nd, 2014, 14:00
A quick and dirty adjustment that gets it in the ballpark is to change the parasitic_drag parameter in the aircraft.cfg from 1.00 to 2.32. (this is for the JF Typhoon)

After this change, with a bit of energy management, I can do a decent final without the airbrake and achieve a maximum speed of 1.25 mach at sea level as per the spec. It will also eventually stall and crash with idle throttle.
This tweak improve things. Deceleration is possible now ;)
Thanks!

big-mike
August 23rd, 2014, 09:38
This tweak improve things. Deceleration is possible now ;)
Thanks!

+1!
Thank you.
Mike

Portia911
August 23rd, 2014, 17:49
I didn't buy the model while on sale even though I have wanted a decent Typhoon for some time. I have encountered this issue with different models that were both overpowered and underpowered and/or had too much or too little drag. The best way to fix them is by updating the airfile thrust and drag parameters but the quick & dirty way is by adjusting the thrust and drag settings in the config file. In this case(and not having hands on to test it), I would suggest lowering the thrust 1000 lbs at a time and if needed, make slight adjustments to the parasitic and induced drag scalars. As a rule of thumb on the thrust and drag, you should be able to turn at max G in afterburner and maintain constant airspeed (at optimum corner velocity) but be able to pull slightly more back pressure to increase drag and begin bleeding off speed and turning tighter while the G also bleeds off. It's a bit tricky to balance these parameters in FSX but it can be done. Worth a try!

For the purposes of this sort of tweaking generally, what is the difference between parasitic drag and induced drag, and when would you look to increase one or the other (or both)?
Thanks

StormILM
August 23rd, 2014, 18:32
For the purposes of this sort of tweaking generally, what is the difference between parasitic drag and induced drag, and when would you look to increase one or the other (or both)?
Thanks

Parasitic drag is caused by objects attached to the airframe that add drag, like external tanks, weapons but also fixed parts of the aircraft structure that may disrupt smooth airflow. Induced drag (also known as Lift drag) which occurs when an airfoil or other lifting surface redirects airflow to create/increase lift. So generally, the parasitic scalar should reflect an average or optimal stores loadings but I'm not sure if this model of the Typhoon has a gauge that renders dynamic capability with the parasitic drag if there was a change in the external stores (ie, dropped bombs or tanks). The Induced drag scalar will affect not only drag in level flight with speed & lift changes but also during maneuvering with speed and AoA changes. Optimally, updating the FDE to get the thrust and drag parameters as close to correct as possible would be the way to go with the config scalars set at 1.0. For now though, the minor adjustments in the config file might help.

Portia911
August 23rd, 2014, 22:12
Alright. Thanks for explaining, Storm.

Stickshaker
August 24th, 2014, 02:04
Sometimes I am surprised that aircraft that are widely used get so little coverage in FSX. The F-4 was one example, but not anymore, and the Eurofighter is another. I do hope that developers like Sim Skunk Works or MilViz will one day make a Typhoon. Or that Just Flight rebrands their present Typhoon as a 'middle range' product for the casual simmer, and makes a 'premium' Typhoon in the same class as their Canberra and Tornado. I cannot imagine that there is not a market for such a plane.