DCS: F-14 Patch Overview - New Autopilot & MP Seat Switching

[Cobra847]

Dear All,

Happy Apache day! Congratulations to the team at Eagle Dynamics for another amazing DCS module release.

While not as exciting as the Apache, today’s patches for the F-14 and Viggen include a couple of key new features and/or overhauled features. We figured we’d give you a quick, more in depth rundown than visible on the changelog as they’re far more comprehensive than they may seem from the changelog itself:
 

F-14 Tomcat Autopilot Overhaul

One of the biggest features for this new patch is a complete rewrite of the F-14 Tomcat’s Autopilot Systems.

This has been a massive undertaking and should have a significant impact on your flying of the F-14 Tomcat. Key design considerations for this overhaul were to bring it closer to reality, make the code more modular, future proof and extensible and to ensure it is flexible enough to handle any future Flight Model updates and handling tweaks still planned.

The Autopilot will now be a far more accurate representation of how the real F-14 autopilot would function and work. Not only on a superficial level, as we took extra care in trying to simulate this particular system as it would function “under the hood” in the real aircraft, yielding the same emergent effects that the real F-14 Autopilot would exhibit. Artificial limitations that may have existed previously, for e.g. engagement zones no longer exist - and it is thus your responsibility to engage the system within operational limits and apply best practices regarding suggested parameters.

To delve into detail; here’s a brief overview of the overhaul, what to expect and the changes introduced:

ATTITUDE HOLD: Still works as it used to, but will feel much more responsive now and “grab” quicker. Limits for this mode are 60° bank and 30° pitch - exceeding these will return the aircraft to within these limits. Note that speed loss during extreme operation may very well lead to a stall of the aircraft or potentially a spin. 

Additionally, exceeding 2.25lbs of longitudinal and 1.25lbs of lateral stick pressure applied during ATT HLD will engage CONTROL STICK STEERING. In this mode, the pilot’s stick inputs override ATT HLD and allow him or her to adjust the ATT HLD, which will re-engage if stick pressure is released again. Trimming is not available during ATT HLD, however if control stick steering is engaged, trimming is available and can help you set your attitude even more precisely and relieve some effort of the autopilot having to “catch up”. 

ALTITUDE HOLD: After further research, we were mistaken to introduce a limit for the engagement range between +/- 200 FPM and thus this has now been removed. Engagement even at very excessive values, say 6000 FPM, is possible, but it is very ill advised. 

For proper use of Altitude Hold, it is suggested to engage it when the aircraft is at or close to level flight or put simply: within approximately +/-200 FPM. The further outside of this limit you will engage it, the bigger resulting oscillations may be, trying to return to the altitude that has been captured on pressing the autopilot reference button. Depending on your speed and AOA this may result in unpleasant, unwanted or downright dangerous behaviour. 

ALT HLD will disengage if 10lbs pressure on the stick’s longitudinal axis is being exceeded or for some reason pitch exceeds 30° plus/minus. If 10lbs pressure is exceeded control stick steering will set in, and once it is released again, will be followed by ATT HLD. 

Re-engagement of ALT HLD will require pressing the AP reference button again. Note that if 1.25lbs pressure of stick input is exceeded on the lateral stick axis (roll), ALT HLD will not disengage, but a combination of ALT HLD and control stick steering will set in until pressure is released again, at which point a combination of ALT HLD and ATT HLD takes over again in absence of other modes such as HDG HLD or GT HLD. This allows the pilot to adjust bank levels while holding altitude at the same time and is very useful for orbits. 

New is also that altitude hold indeed takes a reference altitude it tries to return to - so during steep banks or engagement outside of best practice limits, it will cause it to oscillate (slightly during bank to more severely if engaged outside of suggested limits) until it returns to the captured altitude. If engaged outside of “sane limits” (meaning what no real life pilot would realistically attempt), it very well may not be able to capture the altitude anymore. Noticeable is also that when ALT HLD is engaged the control surfaces cycle at about 1 degree amplitude and about a one hertz rate. 

It is not noticeable from the cockpit, but you will be able to see if your lead has it engaged looking at the horizontal stabs, when flying in formation. This is due to its limitation in update rate, which in return means that you should not roll too fast or too steep when ALT HLD is engaged, or it may not be able to keep up very well. As always, discipline is required and smooth and steady inputs - as one would use in real life. 

HEADING HOLD: Remains as was, although it has the same new inner workings as the other modes, including update rates and limitations, which means that releasing the stick within 5° bank might feel just a touch clunkier, or more immediate with a more distinct “set in” than it did, although this will be barely noticeable in comparison.

Please note that currently there is some minimal drift present, which has already been fixed and will be rectified in the next hotfix or patch, unfortunately we were not able to include this fix last minute. HDG HLD can be used both in combination with ATT HLD or ALT HLD, and will allow for both lateral and longitudinal control stick steering during ATT HLD and lateral control stick steering during ALT HLD. 

The heading itself gets updated, when the stick is released below a certain threshold of lateral stick pressure within +/-5° bank. The lateral stick pressure needed to override it (while being held), is small enough at 1.25lbs so that you can even bank at one or two degrees to adjust your heading precisely until the stick pressure is released again.  

GROUND TRACK HOLD: This is a new feature and has not been present in the F-14 before. GT HLD works similar to HDG HLD, with the difference of holding track over ground versus adjusting for a HDG, if a heading drift is present for example due to high winds aloft. 

The other difference is that it needs to be engaged at wings level with the autopilot reference button. It can be used both in combination with ATT HLD and ALT HLD. However: if the switch is flipped to GT HLD on the autopilot panel while ALT HLD is present, it will disengage ALT HLD and return the autopilot to ATT HLD with the autopilot reference light coming back on. After pressing the autopilot reference button again, and if the ALT HLD switch has been left in its on-position, both modes will engage at the same time. This means that it is in such a case best engaged while both wings level and within +/-200 FPM. Note that when both switches for GT and ALT are in their respective on-positions, engagement of the ALT HLD mode is only possible, if criteria for both modes are met, meaning the pilot has to hold the aircraft wings level. 

Additionally, due to both modes being connected to the AP reference light (and button press), exceeding 10lbs longitudinal stick pressure or 30° pitch will also disengage both ALT HLD and GT HLD, while engaging control stick steering by applying lateral stick pressure will also disengage both modes and return the autopilot to ATT HLD on release. This needs to be kept in mind, if only one of the two modes is intended to be disengaged or overwritten, in which case it is better to return the respective switch on the autopilot control panel to its off-position first.

Overall, our new overhaul of the autopilot is now modelled in a way that it much more accurately reflects the functionality, limitations and emergent effects of the real system and associated control systems. As a large added bonus; this rewrite is a part of our next generation Heatblur codebase and will pay dividends for future aircraft.

A final task to complete remains a revamp of the ACLS. Responsiveness and reliability of the autothrottle has already been greatly improved as a first step, and we now look to a full completion of ACLS based on this new autopilot system. Enjoy!

PD-STT MLC Filter Removed

We’ve removed the MLC Filter from the PD-STT submode. While digging deeper and researching further, we realised that the MLC is designed to be used in PD search modes, where doppler filters are used, and thus not used in PD-STT, as it uses the velocity tracker instead. 

The PD-search modes use doppler filters to determine target speed, so what doppler filter the echo matches is represented with a square brick on the display. In PD-STT the radar instead has a velocity tracker that looks for target returns within a rate gate centred around the target speed. This means that ultimately PD-STT locks should be more stable now and less prone to losing lock, as is now more congruent with the real radar and systems.

New Feature: Switching Seats in Multiplayer

This has been a long standing and frequently requested feature that we’ve wanted to introduce since before the release of the F-14. Only recently, structural changes to the DCS codebase made this actually possible for us to implement. You can now switch between pilot and RIO seat online, just as in Singleplayer!

Please be aware however, that currently 2 players can occupy the RIO seat at the same time. The pilot should in such a case switch back to the pilot seat to prevent any bugs. We hope this can be inhibited in the future, so that when a human player joins an aircraft with only one player in the RIO seat, the “plane’s owner” will be automatically returned to the pilot seat. Please also note: joining the pilot seat is not possible, unless spawning the aircraft fresh, and in order to prevent oddities that our code was not designed for, the aircraft should always be spawned by the pilot. 

Enjoy the world of DCS Multiplayer with a seamless transition between both seats! 

Enjoy these major changes in this patch - we continue our relentless march forward and our focus has now turned towards the early -A, features such as TARPS, in cockpit pilot and more as we start ticking off the last boxes towards an exit out of Early Access.

Thank you all for your passion and support. We’re long overdue for a general update, especially after our latest announcements- so stay tuned as we try to squeeze an update out in between our packed roadmap!

Team Heatblur 
 

[Panny]

Cheers for all the work kings

[XCNuse]

No mention of FLIR here either; is it safe to assume the updated FLIR engine did not make it to the F14 this patch?

[Cobra847]

1 minute ago, XCNuse said:

No mention of FLIR here either; is it safe to assume the updated FLIR engine did not make it to the F14 this patch?

Correct, we had too little time to spend on it and wanted to avoid breaking something by rushing it; but we're confident we'll get it migrated quickly.

[BirdFarm]

Any updates on the early A or A-6 AI? I know that's not the point of this post but I cant find any reliable information anywhere.

 

cheers on the new AP system!

[tangofrown]

Will the AI Pilot be able to take off from the carrier and such? Or is it just like before, you can only tell him to go headings, etc

[IronMike]

7 minutes ago, tangofrown said:

Will the AI Pilot be able to take off from the carrier and such? Or is it just like before, you can only tell him to go headings, etc

Iceman remains as was, and take offs and landings likely will never be possible. It's not a feature that was intended for him at any point, as it would mean to write a distinct AI for him, which is far beyond its intention and the scope of what is currently possible time-wise. Please remember, Iceman was never an intended feature in the first place.

[diditopgun]

Quote

You can now switch between pilot and RIO seat online, just as in Singleplayer!

OH-MY-GOSH !!!

Was waiting for it even before the Tomcat release !

Amazing !

 

[splash]

Hi, congratulations for the patch. How can I switch seats in multiplayer? I joined to a F-14B slot in a multiplayer mission, pilot position. When in cockpit I pressed "2" but nothing happens. Is there some trick?

Thanks.

Edited March 17, 2022 by splash

[NickBrick]

Same, I can't seem to switch seats either.

[RodWan Olds]

Did a fix for the AOA indexer lighting "keybind" make the cut. Noticed this the other day when I thought it was busted after starting at dawn and landing in late morning.

 

I'm also curious when we'll see things like the hand pump and e-flaps / fire bottle get implimented. Are these on the radar at all?

1 hour ago, splash said:

Hi, congratulations for the patch. How can I switch seats in multiplayer? I joined to a F-14B slot in a multiplayer mission, pilot position. When in cockpit I pressed "2" but nothing happens. Is there some trick?

Thanks.

 

Reguarding the seat switching. I had noticed it working for me in the past if the "player seat lock" setting was disabled in the ME. Not sure if this is connected to the issue, but might try it.

Edited March 17, 2022 by RodWan

[sLYFa]

Handpump functionality has been implemented a while ago. Emergency flaps have been there from the start (i.e. outboars spoiler module talking over in case of comb pressure loss). If you mean the emergency functions of the flap handle, emer dn has no function while emer up has the same function as normal up but overrides any lockouts (little use in DCS IMO). 

The fire bottles supposedly work but I havent tested those. A fix for the AoA brightness thumbwheel would certainly be nice though 

[IronMike]

SMALL PSA everyone:

Unfortunately the MP seat switching did not get included properly during the upload, which means it will not be available until the next hotfix/patch. Our apologies for that.

[draconus]

1 hour ago, Gypsy 1-1 said:

Why does this keep happening every major patch recently? Is no one testing the release build?

Imagine ED: Sorry, Apache somehow did not make it this patch 

[IronMike]

2 hours ago, Gypsy 1-1 said:

Why does this keep happening every major patch recently? Is no one testing the release build?

It does not happen every major patch, but if you have to know, part of the networking broke down for everyone. Has nothing to do with testing release builds...

[Indianajon]

I was just coming on this morning to ask about the new autopilot switching as it confused me last night so thank you.  Question,  now that we flick the autopilot on first then select the appropriate switch is the autopilot already aiding attitude, bank etc or does it wait until the next switch is selected before working?

[Golo]

44 minutes ago, Indianajon said:

I was just coming on this morning to ask about the new autopilot switching as it confused me last night so thank you.  Question,  now that we flick the autopilot on first then select the appropriate switch is the autopilot already aiding attitude, bank etc or does it wait until the next switch is selected before working?

The moment you flip autopilot engage switch to engage you are in attitude hold mode of the autopilot (best done when you are level and trimmed), then you can set whatever autopilot mode switches you want and press AP ref button to engage the autopilot modes. Note that attitude hold mode does not require AP ref press to engage, other modes do.

[Indianajon]

Ace thanks Golo

[Beamscanner]

On 3/17/2022 at 6:42 PM, Cobra847 said:

PD-STT MLC Filter Removed

We’ve removed the MLC Filter from the PD-STT submode. While digging deeper and researching further, we realised that the MLC is designed to be used in PD search modes, where doppler filters are used, and thus not used in PD-STT, as it uses the velocity tracker instead. 

The PD-search modes use doppler filters to determine target speed, so what doppler filter the echo matches is represented with a square brick on the display. In PD-STT the radar instead has a velocity tracker that looks for target returns within a rate gate centred around the target speed. This means that ultimately PD-STT locks should be more stable now and less prone to losing lock, as is now more congruent with the real radar and systems.
 

This is actually a very cool technique that nearly all PD radars use. 

 

Range is ambiguous in PD radar (HPRF). So range is resolved via other means (like FMR). However, when a track is initiated, typically the PD radar will

1. Acquire the target (momentary action)
2. Once acquired, perform a range resolve (measure the targets true range) (momentary action)
3. Finally, it will continuously track the target in doppler only (without resolving range). It assumes target range based on the detected doppler motion from the point found in step #2. 

 

ie During track, the radar will know the targets range without having to measure it.

[FigPucker]

Good job with the RADAR improvements.

When can we expect some implementation of ECM effects on the AN/AWG-9?

[scommander2]

4 hours ago, FigPucker said:

When can we expect some implementation of ECM effects on the AN/AWG-9?

me too...

[Bosun]

Any word on track playback fidelity?  

[Northstar98]

On 4/23/2022 at 12:39 PM, FigPucker said:

Good job with the RADAR improvements.

When can we expect some implementation of ECM effects on the AN/AWG-9?

It was shared in the last newsletter.

Quote

Heatblur Simulations will deliver an update to DCS: F-14 Tomcat in the next Open Beta. “Work continues with major improvements and additions. These range from visual features such as the new cockpit pilot models to some of the remaining key features including advanced jamming effects on the radar and associated displays”.
 - Heatblur Simulations

[Nealius]

I'm having a little trouble with the new AP functions. On paper they make sense to me, but in the cockpit they aren't quite behaving the same, at least not ALT and HDG hold.

I engage HDG and ALT hold, engage AP switch, press altitude reference button. So far so good. Except two issues I've experienced:

1. With asymetric load (LANTIRN) the HDG hold won't hold, and I slowly yaw.

2. After disengaging the AP (AP switch off, ALT and HDG hold switches automatically disengage), the roll axis behaves normally but the pitch axis seems to still be stuck in ALT hold. I have to excessively move the stick to "break" out of ALT hold even after disengaging it (and the AP completely).

Is it something I'm doing wrong, or are those kinks that will be ironed out?

[scommander2]

I am wondering that will the patch address the throttle can't be forward after the auto throttle enabled?

 

Thanks.