F-18 Flaps

[lasallecrew2]

I'm not sure if anyone else has this issue... I just purchased the Acceleration Pack and noticed that when the F-18 is on the ground, the flap settings work fine.  As soon as I get shot off the carrier, the flaps (set to 1) are suddenly put to the "up" or clean position.  When I extend the flaps from what should be clean to "half", it shows and acts as if they are "up" and when I put them as "full" then show and act as if they are half.

Anyone else have this issue?  Anything I can do?


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[Razgriz]

It is the autoflap feature.   

[virtuali]

Anyone else have this issue?  Anything I can do?

It's not an issue: the real F/A-18 has Autoflaps. They automatically extend and retract, depending on certain parameters in the flight, like speed and angle of attack.  In this airplane you don't directly control the flap position with the flap control, you control the amount of flap extension that the autoflap logic is allowed to use.

[residual8effects]

Anyone else have this issue?  Anything I can do?

It's not an issue: the real F/A-18 has Autoflaps. They automatically extend and retract, depending on certain parameters in the flight, like speed and angle of attack.  In this airplane you don't directly control the flap position with the flap control, you control the amount of flap extension that the autoflap logic is allowed to use.

This kills me every time i read it, as a Airframes/Hydraulics Mech on the F-18 this is compleatly false. The 18 has 3 flap selections, AUTO, HALF, and FULL... the ONLY time the flaps are controlled by the FCS is when its set to AUTO... HALF is HALF and FULL is FULL... read the A1-FA18AC-570-100. I wont go off on a compleat rant, becouse you guys did a relatively good job with the 18 in acceleration, but this is one of the "works as intended" that makes me realize there was no real consultation involved in development.

[Aeroman]

I'm sure they had consultation; could just be a result of misunderstandings and misinformation.

[Intrepid]

Anyone else have this issue?  Anything I can do?

If you are comfortable changing the aircrafts cfg files ,,you can deleate the auto-flap function
I did and ,to me , it works much better
Randy

[virtuali]

This kills me every time i read it, as a Airframes/Hydraulics Mech on the F-18 this is compleatly false. The 18 has 3 flap selections, AUTO, HALF, and FULL... the ONLY time the flaps are controlled by the FCS is when its set to AUTO... HALF is HALF and FULL is FULL... read the A1-FA18AC-570-100.

According to the F18AC-NFM-000 manual, the behaviour is as follows:

With PROM 5.1.3 the logic is:

AUTO : The FCS goes into auto-flap up mode with Gear Up. With Gear down, the FCS is in auto flap up mode above 215 knots accelerating or 205 knots decelerating

HALF : FCS it's in take-off mode up to 215 knots accelerating or 205 knots decelerating. Above this speeds, the FCS goes into Auto-flaps up mode.

FULL: FCS it's on land mode up to 170 knots accelerating or below 165 knots decelerating. From 170 accell. or 165 decel. it goes into takeoff mode, and abot 215 accell or 205 decel. it goes into Auto flaps up mode.


After PROM 7.0, the logic has been modified as follows:

AUTO: FCS is in auto flap up mode

HALF: FCS in in takeoff and land mode below 250 knots. Above 250 knots FCS is in auto flaps up mode.
FULL: Same as in HALF mode


The 3 different FCS flaps modes are as follows:

Auto Flaps Up mode: Leading and trailing edge flaps are scheduled as a function of the AoA

TakeOff mode: Leading edge flaps are scheduled as a function of the AoA. When on Ground, their are set to 12°. Trailing edge flaps are set to 30°.

Land mode: Leading edge flaps are scheduled as a function of the AoA. When on Ground, their are set to 12°. Trailing edge flaps are set to 45°.

This is what the flight manual says.

During developement, we programmed the flaps behaviour verbatim to these specs, handling the logic of the flaps within our code, because FSX never had an Auto-flaps system of any kind.

However, this conflicted somewhat with the upgraded Acceleration flight model that ACES was developing in the meantime, including the addition of the Auto-flaps system, that is just a switch that can be enabled in the AIRCRAFT.CFG file and it's handled by the FSX flight model. Also, there were some side effects, because we had to "fight" against the user pressing the flaps keys when he wasn't supposed to do so.

It was decided that the real Auto-flaps logic, as originally programmed, was too confusing for beginners who might have wondered why the flaps didn't always respond to their inputs and, since Acceleration introduced the Auto-flaps system, the released F-A/18 use that one instead, which still has a logic that controls flaps depeding on AoA, but being an integral part of the flight model system, is also able to deal more gracefully with user acting on flaps manually in one of the automatic modes.

We don't know exactly the operating parameters of the default auto-flaps system so, for example, at which speeds the Auto flaps up mode (which both leading and trailing edge flaps are set according to AoA) kicks in, but I guess ACES did a generic implementation that probably figures out the speeds according to other parameters in the flight model, so it can be used on a wider range of airplanes.

So please, don't assume that if something it's not 100% like the real thing, it's because we don't know how is supposed to work. Everything it's usually the result of a design decision, and FSX Acceleration Pack is not geared only to the hard-core simmers, but it has to be used by a much wide range of users compared to the typical 3rd party addon. That's why some things were simplified.

[Ray]

Thank you virtuali for the insight. This subject was on my mind since I heard about the Hornet for FSX. Besides the main landing gear (compression) issue, this was one thing I thought that needed improvement.

So if the aircraft.cfg file is edited as suggested, do the trailing edge flaps and leading edge flaps drop to the intended angles of 30° and 45° and 12° (plusminus AOA factor) in HALF and FULL mode respectively? Can anyone post a screenie of that maybe. I am just curious.

BTW, is the rudder toe-in (by 20°) in HALF and FULL mode modeled too?

[SUBS17]

It was decided that the real Auto-flaps logic, as originally programmed, was too confusing for beginners who might have wondered why the flaps didn't always respond to their inputs and, since Acceleration introduced the Auto-flaps system, the released F-A/18 use that one instead, which still has a logic that controls flaps depeding on AoA, but being an integral part of the flight model system, is also able to deal more gracefully with user acting on flaps manually in one of the automatic modes.

Never worry about noobs getting confused just model stuff the way it is in the book the noobs will pick it up.

[virtuali]

Never worry about noobs getting confused just model stuff the way it is in the book the noobs will pick it up.

Don't forget that what we did for the F/A-18 has been published by Microsoft, as part of a bigger package. It has to be approachable by all kind of users. The average guy that gets in contact with something that doesn't behave as expected and it's different than FSX default, might think it's a bug ( "why my flaps acts like this..!!").

I do recall an exemplary story, from FS5 days:

FS5.0 had this bug: if a runway had an ILS without an associated DME on the same frequency (which is absolutely normal and very common), the program never honored that flag, and *always* displayed the distance on the affected gauges, which was of course wrong.

FS5.1 fixed the bug: if the ILS in the scenery had the DME flag set to off, the program didn't display the distance, which was correct.

I had a flight sim shop (a real shop) these days and, since the ILS without DME with DME on a different VOR is *very* common in Italy, you wouldn't believe how many telephone calls I had from customers when FS5.1 was released, that they found a "bug", becasue the DME that used to work before on their favorite airport, didn't worked anymore in 5.1, so it was obviously a bug...

[Aeroman]

hahaha!  noobz...

[SUBS17]

For issues like that you would post it in the readme file or on a website by subtracting realism from a feature for such an aircraft as a Hornet you lose credibility otherwise. As it is the Flap switch isn't a show stopper like other things such as trim and its difficult to gauge whats is realistic or not unless you have an actual Hornet pilot there to verify what it should and shouldn't do I think its cool when people develop aircraft for flight sims the more complex the better. Or perhaps scalable complexity could be a work around Option 1 full realism 2 scaled down for noobs.

[virtuali]

I think its cool when people develop aircraft for flight sims the more complex the better. Or perhaps scalable complexity could be a work around Option 1 full realism 2 scaled down for noobs.

Sorry, but you are keep not getting the point: we would agreed to all these suggestions, if we were to publish the airplane on our own. In fact, we ALREADY did something like that in the past: on the F-104 we did for Cloud9, we had 3 separate flight models with separate simulation code, one which was just easy and fun to fly, another one that was as tricky as the real one, and a third one which added several failures on top of that.

But that's not how a default airplane is done (Acceleration now comes as standard in the latest FSX reprint). If you compare it with other default airplanes, the F/A-18 is already way more complex than usual, and don't forget we only did avionics and the VC modeling, something like the flaps simulation is strictly tied to the flight model and, since ACES introduced an auto-flaps system for the Acceleration package, it's only normal they'd wanted to use it.

[SUBS17]

Yeah I can understand that situation its similar to other sims in the past that were working for publishers with deadlines and limitations on what they can and can't do. Some sims now days the companies making the sims are not using publishers to avoid that problem and also to give them time to make the sim. Its a pity that FSX can't support combat which is a major drawback when making any military addon jet for FS have you guys ever considered DCS?

[vortex_25]

If you are comfortable changing the aircrafts cfg files ,,you can deleate the auto-flap function
I did and ,to me , it works much better
Randy

How does one go about doing this?

Which lines in the aircraft.cfg file need to be removed / modified?