cannot reproduce and missing track file Takeoff trim trouble with the F18

[Tree_Beard]

Usually I just push the T/O trim button during cold startup on the carrier and ignore the recommended trim per weight, since the plane doesn't really seem to have any trouble launching at 12 degrees even with a full loadout.

However, I have recently been getting the annoying "CHECK TRIM" warning on my left DDI after takeoff, and every time I spool up the engines, even 30+ minutes after launching, I get a master warning light and beeping. Flaps being set to auto doesn't seem to matter. 

So, I decided that from now on, maybe I'll start doing things by the book and trimming the aircraft correctly per weight for launch. Here's the problem I am having now -

While hooked up on the catapult, I use my trim hat to pull the flaps back to 16 degrees, referencing the checklist DDI page. It seems to take a weirdly long time for the flaps to move from 12 to 16, holding back on the trim hat, but whatever I guess.

Then comes the real issue. I launch from the cat, and the jet immediately wants to pitch up really hard, so I have to press hard nose down to keep it level. And at this point, even when I flip the flaps switch to auto, the jet continues pitching up. Like my trim will not go back to neutral, whether I set the flaps switch to auto, press FCS reset or a key that I bound to trim reset... the trim wont change. 

I am sure I'm doing something wrong here, can someone figure out what my problem is? 

[rob10]

Are you in "GAME" mode rather than "SIM"?  That and taking off in AUTO are usually the 1st 2 culprits for that symptom IIRC.

[Tholozor]

Never take off with flaps in AUTO, only HALF or FULL. Adjusting takeoff trim with the trim switch should also only be done with flaps in HALF or FULL.

Edited April 12, 2023 by Tholozor

[Tree_Beard]

9 minutes ago, rob10 said:

Are you in "GAME" mode rather than "SIM"?  That and taking off in AUTO are usually the 1st 2 culprits for that symptom IIRC.

Sim mode. Always take off with flaps set to half. 

1 minute ago, Tholozor said:

Never take off with flaps in AUTO, only HALF or FULL.

Flaps set to half for takeoff. 

[Tholozor]

You'll probably have to post a track then, because it sounds exactly like flaps are in AUTO.

[Hulkbust44]

FCS BIT switch stuck up?

[rob10]

Or check that you don't have a binding issue that's forcing your trim up.  Do you have the same issue taking off from a ground airport?

[Dangerzone]

3 hours ago, Tree_Beard said:

Usually I just push the T/O trim button during cold startup on the carrier and ignore the recommended trim per weight, since the plane doesn't really seem to have any trouble launching at 12 degrees even with a full loadout.

However, I have recently been getting the annoying "CHECK TRIM" warning on my left DDI after takeoff, and every time I spool up the engines, even 30+ minutes after launching, I get a master warning light and beeping. Flaps being set to auto doesn't seem to matter. 

So, I decided that from now on, maybe I'll start doing things by the book and trimming the aircraft correctly per weight for launch. Here's the problem I am having now -

While hooked up on the catapult, I use my trim hat to pull the flaps back to 16 degrees, referencing the checklist DDI page. It seems to take a weirdly long time for the flaps to move from 12 to 16, holding back on the trim hat, but whatever I guess.

Then comes the real issue. I launch from the cat, and the jet immediately wants to pitch up really hard, so I have to press hard nose down to keep it level. And at this point, even when I flip the flaps switch to auto, the jet continues pitching up. Like my trim will not go back to neutral, whether I set the flaps switch to auto, press FCS reset or a key that I bound to trim reset... the trim wont change. 

I am sure I'm doing something wrong here, can someone figure out what my problem is? 

I've come across this issue from time to time. Sometimes (with airspeed slowed appropriately), lowering the gear back down and putting flaps into auto has resolved the issue for me. I never got around to figuring out what was the actual cause. For me it didn't so much happen on initial takeoff, than it did after landing, and taking off a second time. 

 

[Brun]

On 4/12/2023 at 1:21 AM, Tree_Beard said:

It seems to take a weirdly long time for the flaps to move from 12 to 16, holding back on the trim hat, but whatever I guess.

This also seems consistent with flaps being set to AUTO.

I'd noticed previously when preparing to take off that the trim didn't seem to change at all until I set flaps to HALF. When checking again it does, but slowly.

[Tree_Beard]

9 hours ago, Brun said:

This also seems consistent with flaps being set to AUTO.

I'd noticed previously when preparing to take off that the trim didn't seem to change at all until I set flaps to HALF. When checking again it does, but slowly.

I think you are right. I was trying to record a track to post here but when I am double checking to make sure I have flaps set to "half" while on the ramp, it seems like my manual pre-launch trim adjustments do correctly reset to neutral when I flip the switch to "auto" after launching. I swear I was doing that before as well, but I guess not. 

Edited April 13, 2023 by Tree_Beard