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Posted

The F-18 like most modern jets got FBW, the pilot's inputs are simply taken in by the flight computer and the plane then decides what to do with them. ;)

 

So there isn't any "force feedback" in reality, that's why I think there is no point to have it in our sim.

Posted
The F-18 like most modern jets got FBW, the pilot's inputs are simply taken in by the flight computer and the plane then decides what to do with them. ;)

 

So there isn't any "force feedback" in reality, that's why I think there is no point to have it in our sim.

 

You are very, very wrong...

 

Here is a small bit from F/A-18 flight manual:

 

2.8.2 Primary Flight Controls.

 

. Hydraulic actuators

position the control surfaces. Stick and rudder feel are provided by spring cartridges. Although there

is no aerodynamic feedback to the stick and rudder pedals, the effect is simulated by flight control

computer scheduling of control surface deflection versus pilot input as a function of flight conditions.

 

* * *

 

11.1.5 Stick Force. In maneuvering flight, there is a light but constant stick force per g (about 3.5 to

4.5 pounds/g). Unlike many other aircraft, maneuvering stick forces do not vary significantly over the

entire operating envelope as long as the AOA is less than AOA feedback of 22°. Where AOA feedback

is active, maneuvering stick forces are increased significantly.

Posted
You are very, very wrong...

 

Here is a small bit from F/A-18 flight manual:

 

2.8.2 Primary Flight Controls.

 

. Hydraulic actuators

position the control surfaces. Stick and rudder feel are provided by spring cartridges. Although there

is no aerodynamic feedback to the stick and rudder pedals, the effect is simulated by flight control

computer scheduling of control surface deflection versus pilot input as a function of flight conditions.

 

* * *

 

11.1.5 Stick Force. In maneuvering flight, there is a light but constant stick force per g (about 3.5 to

4.5 pounds/g). Unlike many other aircraft, maneuvering stick forces do not vary significantly over the

entire operating envelope as long as the AOA is less than AOA feedback of 22°. Where AOA feedback

is active, maneuvering stick forces are increased significantly.

I don't think you understood this text, this highlights even more the fact that ffb is almost pointless for a fbw jet.

 

Stick force Vs g force stays constant over most of the flight envelope. So basically a stick with a spring return to center is quite close to the real thing

 

Sent from my VTR-L09 using Tapatalk

Posted (edited)
11.1.5 Stick Force. In maneuvering flight, there is a light but constant stick force per g (about 3.5 to 4.5 pounds/g). Unlike many other aircraft, maneuvering stick forces do not vary significantly over the entire operating envelope as long as the AOA is less than AOA feedback of 22°. Where AOA feedback is active, maneuvering stick forces are increased significantly.

 

Force feedback from the FBW of the F-18 confirmed in plain english.

 

The best force feedback stick out there is still the Microsoft Sidewinder Force Feedback 2.

 

There are two versions: the green status light and the red status light, the latter is a the later model with a sticky grip. The firmware in both is supposed to be the same, so the force feedback performance should be identical in both the green and the later red models.

 

I keep hunting for them on ebay, they green ones usually sell at around 35 to 50 usd. The red ones usually sell a bit higher, I've seen them sell at over 80 usd in some cases.

 

When I find one at a good price I buy!

Edited by ViFF

IAF.ViFF

 

http://www.preflight.us

Israel's Combat Flight Sim Community Website

Posted
Force feedback from the FBW of the F-18 confirmed in plain english.

 

The best force feedback stick out there is still the Microsoft Sidewinder Force Feedback 2.

 

There are two versions: the green status light and the red status light, the latter is a the later model with a sticky grip. The firmware in both is supposed to be the same, so the force feedback performance should be identical in both the green and the later red models.

 

I keep hunting for them on ebay, they green ones usually sell at around 35 to 50 usd. The red ones usually sell a bit higher, I've seen them sell at over 80 usd in some cases.

 

When I find one at a good price I buy!

This is probably why Force Feedback joysticks died, manufacturers heard that most people don't know or don't care about force feedback.

I remember a funny story how research showed that many iPhone 4 users thought that their phone already supports 4G :D

 

I also have a little stock of MS FF2, 5 so far (and TM cougar, just for the stick to mod with MS FF2 base), one G940 and Logitech Force 3D (which I plan to mod into FF rudders).

 

This should hopefully keep me through FF dark ages, if not, there is a community effort here this forum trying to develop diy FF stick!:

https://forums.eagle.ru/showthread.php?t=172964

Posted

Only variable thing physically acting on the stick forces is the stand-by trim motor, which re-positions the neutral when normal trim acting through FCS gains is not available. There is no force feedback, as in actuators driving the stick, in the Hornet.

 

Control forces are simulated by requiring you to move the stick in different amounts, depending on the flight parameters. Control laws and stick function is explained in reasonable detail in NATOPS for instance. It can be force-per-g, but at lower speeds/higher alphas, pitch rate and alpha feedbacks are thrown in the mix. Essentially the control force simulation works in a Hornet precisely the same way they work in a simulator when flying with non-FFB stick.

Posted
Only variable thing physically acting on the stick forces is the stand-by trim motor, which re-positions the neutral when normal trim acting through FCS gains is not available. There is no force feedback, as in actuators driving the stick, in the Hornet.

 

Control forces are simulated by requiring you to move the stick in different amounts, depending on the flight parameters. Control laws and stick function is explained in reasonable detail in NATOPS for instance. It can be force-per-g, but at lower speeds/higher alphas, pitch rate and alpha feedbacks are thrown in the mix. Essentially the control force simulation works in a Hornet precisely the same way they work in a simulator when flying with non-FFB stick.

 

LOL

 

USMC_Trev said it well.

 

hqdefault.jpg

Posted

Of course it will be implemented.. no need to argue on this.

Specs:

Asus Z97 PRO Gamer, i7 4790K@4.6GHz, 4x8GB Kingston @2400MHz 11-13-14-32, Titan X, Creative X-Fi, 128+2x250GB SSDs, VPC T50 Throttle + G940, MFG Crosswinds, TrackIR 5 w/ pro clip, JetSeat, Win10 Pro 64-bit, Oculus Rift, 27"@1920x1080

 

Settings:

2.1.x - Textures:High Terrain:High Civ.Traffic:Off Water:High VisRan:Low Heatblur:High Shadows:High Res:1920x1080 RoC:1024 MSAA:4x AF:16x HDR:OFF DefS: ON GCI: ON DoF:Off Lens: OFF C/G:390m Trees:1500m R:max Gamma: 1.5

 

Posted

There are no forces moving the stick from the neutral, or altering the force required to displace it, in the Hornet. There is only spring centering. The airplane response is what is altered to provide a simulation of control feel.

 

The trim motor is used to drive the stick's neutral position, to which the springs center it, in flight control modes which provide a direct relationship in between the stick position and the stab angle, to provide a physical trim. In regular modes, the trim is electrical, with no effect on the spring centering.

Posted
There are no forces moving the stick from the neutral, or altering the force required to displace it, in the Hornet. There is only spring centering. The airplane response is what is altered to provide a simulation of control feel.

 

The trim motor is used to drive the stick's neutral position, to which the springs center it, in flight control modes which provide a direct relationship in between the stick position and the stab angle, to provide a physical trim. In regular modes, the trim is electrical, with no effect on the spring centering.

 

The irony is, even if you are right (and you're not) this would be much better simulated on a force feedback stick. :megalol:

 

The truth is that pilots might break their neck if they could pull a 7G turn with same amount of force as for a 1G turn...

Posted
The irony is, even if you are right (and you're not) this would be much better simulated on a force feedback stick. :megalol:

 

The truth is that pilots might break their neck if they could pull a 7G turn with same amount of force as for a 1G turn...

What ?? No one said that, the force increase linearly with the aircraft g-loading, starting a climb at 2g will require a certain amount of force let's say : 10N (I don't know the actual force Just for explanation), and if you want to climb harder, let's say 5g: you have to pull harder 50N .

 

For the extraction of the manual quoted : this relation is linear (=like spring), and stays the same for most of the flight envelope.

 

Ok I agree that they are exceptions when in extreme flight regime ( low speed, very high AOA).

 

But still a spring is very close to the actual stick forces, during most of the flight

 

Sent from my VTR-L09 using Tapatalk

Posted (edited)

The AOA feeback is in the control law, which produces an aircraft nose-down command proportional to AOA above 22 degrees. So pilot would pull more above 22deg AOA. This is not force feedback applied on the stick, but FCS feedback that will affect control surface deflection.

 

7.jpg.7f2bb662e4424e69a6cab2ea8fe3038b.jpg

 

 

BTW I really want to see a 35 pound force FFB stick. Now I'm just sticking to my 22-pound X65F.

Edited by LJQCN101

EFM / FCS developer, Deka Ironwork Simulations.

Posted

Trouble is, many people don't know what actual fighter jet feels like to fly (shame because there is a lot of material on the internet, even reports from actual pilots):

 

"I was invited to fly the aircraft into a high alpha regime. I pulled off the power at Dave's instruction and applied aft stick to bleed off airspeed while holding altitude. At about 30 degrees alpha a distinct rumbling sound developed, as the airflow over the aircraft began to break up into turbulent flow, yet the handling did not perceptibly change. Stick force however did increase noticeably, as I approached 3/4 aft stick deflection I needed both hands to comfortably pull the stick back further. Holding 90 KIAS I pulled the aircraft gradually back to 48 degrees alpha, while Dave worked the throttles.

 

The aircraft was very stable throughout entry and the progressive increase in AoA, there was no perceptible rolling sensitivity in lateral stick inputs, the knife edge balance preceding a wing drop which one would intuitively expect as a result of the aircraft's speed and angle of attack was absent. From the pilot's perspective, the feel is very solid and smooth.

 

Small lateral stick inputs yielded a proportionate response, there was no perceptible reduction in control input sensitivity in this regime. To exit from the manoeuvre, I released the aft stick pressure, and as the aircraft unloaded Dave pulled back the power."

 

http://www.ausairpower.net/SuperBug.html

 

Please can we stop arguing over this?

Posted
The irony is, even if you are right (and you're not) this would be much better simulated on a force feedback stick. :megalol:

 

The truth is that pilots might break their neck if they could pull a 7G turn with same amount of force as for a 1G turn...

You misunderstand on purpose. AoA feedback increases stick forces per g by requiring you to pull the stick further back when active for the same g response. High-AoA flying is one of the few areas where almost full-aft stick is needed at all in Hornet.

 

Force required to pull the stick full aft to the stop is modestly strong, albeit at least I can pull it to the stop with one hand relatively easily. I'd only guess by feel it is maybe around 40 lbs, but I don't know - on ground it also depends where the stand-by trim motor has left the feel springs; if you test the motor when doing ground crew's daily check for instance, you typically don't bother to center it to neutral.

Posted
You misunderstand on purpose. AoA feedback increases stick forces per g by requiring you to pull the stick further back when active for the same g response. High-AoA flying is one of the few areas where almost full-aft stick is needed at all in Hornet.

 

Force required to pull the stick full aft to the stop is modestly strong, albeit at least I can pull it to the stop with one hand relatively easily. I'd only guess by feel it is maybe around 40 lbs, but I don't know - on ground it also depends where the stand-by trim motor has left the feel springs; if you test the motor when doing ground crew's daily check for instance, you typically don't bother to center it to neutral.

 

I still can't get over what you said earlier:

 

"Essentially the control force simulation works in a Hornet precisely the same way they work in a simulator when flying with non-FFB stick."

 

This is realistic in the same way a broken clock is correct twice a day.

Maybe flying through checkpoints in airbus fashion (when most people use autopilot), and maybe on the ground.

In every other aspect of the flight the spring joystick is not realistic.

(spring does not know what is G)

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