acknowledged ACLS landing too hard, too steep, comes up short, and bolters

[David A Sell]

My ACLS functions perfectly as expected, however after the ball call it seems to come down too hard, a bit short, and always results in a bolter. In this test there is zero wind, and the carrier is steaming at 29 knots

TRK file attached, Youtube vid (sped up) attached 

 

 

server-20250703-005600.trk

[David A Sell]

Okay doke, this time I went in AirBoss slot, made absolutely sure boat was set up in parameters, then shot the approach. I THOUGHT I had it figured out by ensuring setting my altimeter to 2993 (as I was not positive it was changed from 2992 on previous attempts).

I was thrilled when the approach looked pretty good, and actually (barely) snagged a one wire... I am unsure if it was the 2993 setting, using the AB slot to ensure boat was set up for recovery, or a little of both; however, in the end, the plane still came down steep, and hard enough to bend the gear. I just know this isn't right... I am at a loss.

 

 

I am curious if coupling up after having my ATC set is causing a problem. I was assuming, probably incorrectly, that when coupled and in ATC the jet would modulate the throttles as needed for a good landing... In this case I set my ATC at 148, 8 knots faster than commanded by the ACL, and it looks like it stayed at 148 the whole time, (though I would think the extra speed would make me go long and not smack down short.)

track.trk

Edited July 13 by David A Sell

[David A Sell]

Redid test to be bang on 140knots as commanded, still bolters / and/or hits hard and bends gear every time. ensured my altimeter is correct as commanded, am on all parameters given by ACL, boat is 29 knots and my weight is below 31k. Latest example (13JUL25 below) 

 

tracktest2.trk

[BIGNEWY]

Hi, 

Please remove all mods you have in DCS world before creating a trackfile. We cannot replay it because of that.
After removing the mods, please try again and attach the track again.

thank you 

[David A Sell]

Hello Bignewy, Thank you. 

(I do have one Mod called GCbase, I will remove and re-record a proper track) 

I  have always launched DCS from the vanilla launcher and do not know of any mods that I have ever  installed? (Aside from skins) 

The mission did have a couple scripts like moose and CTLD, I removed them all and tried another Trackfile, hopefully that works, if not I can try and repair build or do a clean install. .

(Mod folder contents below)

 

trackfromllanding.trk

Edited July 16 by David A Sell

[PawlaczGMD]

Do you have wake turbulence on? I've found it is too strong and doesn't work well with ACLS. Try turning it off and see again.

[BIGNEWY]

22 minutes ago, David A Sell said:

Hello Bignewy, Thank you. 

(I do have one Mod called GCbase, I will remove and re-record a proper track) 

I  have always launched DCS from the vanilla launcher and do not know of any mods that I have ever  installed? (Aside from skins) 

The mission did have a couple scripts like moose and CTLD, I removed them all and tried another Trackfile, hopefully that works, if not I can try and repair build or do a clean install. .

(Mod folder contents below)

 

trackfromllanding.trk 7.14 MB · 0 downloads

Hi, 

any unofficial mods will be in the saved games dcs mods folder, not the root install of dcs. 

If you attach your dcs log it will give us some more data. 

 

[David A Sell]

Ok Apologies, I think I have all mods and such removed, ran a couple file repairs, this should be a good to go trackfile attached 

youtube of the final phase of that trackfile below. 

 

cleantracknomods.trk dcs.log

[BIGNEWY]

Thank you for the new tracks, 

 you need to decouple when calling the ball for a manual trap. ACLS is NOT designed to be engaged all they way to the trap. 

Later systems like "magic carpet" allowed full hands off trap, but not ACLS

when calling the ball, use the paddle to disengage ACLS

hope that helps 

[Canada_Moose]

3 hours ago, BIGNEWY said:

Thank you for the new tracks, 

 you need to decouple when calling the ball for a manual trap. ACLS is NOT designed to be engaged all they way to the trap. 

Later systems like "magic carpet" allowed full hands off trap, but not ACLS

when calling the ball, use the paddle to disengage ACLS

hope that helps 

That doesn't seem to line up with the video that Wags did when ACLS was released? 

Mode 1 - fully coupled and hands off until on deck

Mode 1A - disconnect AP at ball call

Did things change?

Edited July 17 by Canada_Moose

[BIGNEWY]

I will ask Wags, it could be the video is incorrect. 

 

[Minsky]

5 hours ago, BIGNEWY said:

I will ask Wags, it could be the video is incorrect. 

No, the video is true to the real-world documents. You're confusing MODE 1 and MODE 1 ALPHA.

[macedk]

Just tried and mine failed too. Bent the gear. 
Trackflie

Picture is from a declass acls manual from 1982 (link:https://web.archive.org/web/20240420151952/https://apps.dtic.mil/sti/tr/pdf/ADA118181.pdf ). Page 15. 

On the DCS side, Plane does a massive power cut  approx.. 2 seconds before touchdown. Decent rate goes from - 700ft/min to -1000ft/min. 

Touchdown point is well before 1. wire and plane skibs all wires. 

If only Mode1A is modelled than Bignewy is correct.

ACL bolter 2.trk

[macedk]

Additional info Found this video. 
Take note of decent rate and fuel flow. 
Note: video is from 24.Jan 2025, so older DCS version and something might have changed :).  Video link is just before touchdown. 

 

[David A Sell]

18 hours ago, Canada_Moose said:

That doesn't seem to line up with the video that Wags did when ACLS was released? 

Mode 1 - fully coupled and hands off until on deck

Mode 1A - disconnect AP at ball call

Did things change?

Concur. I used to go hands off all the way to the trap every time, basing my workflow step by step on Wags original ACLS video. It seems to have changed sometime in the last 4 months. 

Edited July 18 by David A Sell

[G B]

23 hours ago, BIGNEWY said:

Thank you for the new tracks, 

 you need to decouple when calling the ball for a manual trap. ACLS is NOT designed to be engaged all they way to the trap. 

Later systems like "magic carpet" allowed full hands off trap, but not ACLS

when calling the ball, use the paddle to disengage ACLS

hope that helps 

BigNewy,

 

ACLS can land the aircraft completely automatically. It is called ACLS “Mode 1.”

 

Magic Carpet, now called PLM, is hands-ON. 
 

Please let me know if you have any questions. Thank you for your time. 

[PawlaczGMD]

This definitely used to work all the way to touchdown.

[AndyJWest]

Wags' video: Mode 1 hands-off landing from 16:00 on.

 

[BIGNEWY]

Hi all, 
I have checked with the team, and we currently most accurately support Mode 1A. It’s quite possible that something has changed since Wags originally recorded that video.
There are a couple of carrier recovery items to fix that we are aware of for manual approach, that should then address the Mode 1 issues you bring up.
Thank you.

[David A Sell]

Thanks BIGNEWY, we appreciate the responsiveness. (It's very hard to land manually after a few cold ones!)