F18 Trim?

Question, when press the “takeoff trim button”, does it always set 12 units, regardless or takeoff weight? And then you adjust higher for T/O weight? Or given that it knows your weight based on fuel and weapons loadout, will it adjust accordingly?

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AFAIK , it always sets 12 ° , and you manually increase for increased weights for carrier launches only . Carrier launches are "hands off " .
Personally , i always set 12° for airfield takeoffs , regardless of weight . Today for example , I took off with 4 MavF’s , 2 sidewinders , a full gun load , a Litening pod , and full internal fuel , and the aircraft flew itself off the runway .

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I experimented this morning (UK time). A clean F18 with internal fuel.

  • Launched of Stennis hands off the controls. Full reheat, Half flap, V pressed giving stab 12. No effort by the aircraft to fly. ballistic launch into the sea.

  • Same configuration out of Nellis AFB. Same take off parameters. No attempt to nose up by the aircraft. Reached 240kts at the end of the runway. I stayed hands off. Stab moved from 12 to 24 during acceleration.

Perplexed. It used to take off on its own hands free as in a real F18. I suspect this maybe related to why it wont trim.

While I haven’t tried clean off deck recently, 12° has never been sufficient for a carrier takeoff even lightly loaded. Try maybe 14°. When you draw the flaps in, it should pitch up a bit as well.

Perhaps try a DCS repair, just to be safe. Even when it says nothing to fix I have found it has helped some strange issues.

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12 is what setting trim for take off does. The ‘V’ key. It has always been sufficient to allow the aircraft to rotate itself into the climbing attitude. It is only been recently that I have developed a problem with trim. I have tried your suggestion re DCS repair. In fact I have done a total re installation. The snag is still there. Tonight (BST) VicktorK2 is going to watch over my shoulder and check a few things to try and fault find.

Thanks for the help

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Please post a track.

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I will send one later

Good stuff, the reinstall may have been a bit much but won’t hurt. I’ll try to hop into a few tests myself and report back.

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Couple things that come to mind:

  • There’s currently a “negative ground effect” bug with the Bug. I don’t know if this affects runway takeoffs, but it wouldn’t surprise me; I always start pulling back on the stick at ~150 knots.

  • Carrier launches are to be performed with a minimum of 16 degrees of up elevator trim, not 12. 12 is for runway takeoffs only. NATOPS trim settings: <44,000lbs gross weight - 16 deg; 45-48,000lbs - 17 deg; >49,000lbs - 19 deg. I’ve never had to touch the stick using these trim settings. There’s also trim settings for differential stores, but I don’t have the chart handy.

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I haven’t messed with it too much lately, I’ll see if I can boot it up and take a couple notes on my impressions this weekend.

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Here’s the chart for asymmetrical stores:

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Thanks for that. Has reduced the distractions on launch!

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To continue on the chart: @Wes found the distance from centerline for the inside and outside hardpoints as 7.3’ and 11.2’ respectively. I am not 100% certain (so someone feel free to set me straight; numbers are not my strong suit), but I believe it works like this: multiply weapon weight on the station by the appropriate distance figure, then subtract both sides from one another to get your asymmetric store moment.

Example:

Right Inner: 2535lbs (330gal tank) = 25357.3 = 18505.5 ft/lb
Right Outer: 761lbs (AGM-65E + rail) = 761
11.2 = 8523.2 ft/lb
Left Inner: 532lbs (GBU-38) = 5327.3 = 3883.6 ft/lb
Left Outer: 1386 (GBU-12
2 + BRU rack) = 1386*11.2 = ‭15523.2‬ ft/lb

Right moment total: 18505.5 + 8523.2 = 27028.7‬ ft/lb
Left moment total: 3883.6 + 15523.2 = 19406.8‬ ft/lb

Subtract the left from right to get a difference of 7621.9‬ ft/lb in favor of the right. As the scale starts at 10,000lbs of difference, we would add 2 degrees of left wing down trim to compensate.

I’ve tested this in game and it does make a huge difference on catapult launches.

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Works perfectly on multiplayer, snags persist in single player

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Might it be that in the options screens you have certain options set that are making life hard for you in SP but that are forced to a more sensible setting by the MP server?

Take a gander at the gameplay and special tabs.

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When I read “hands off”, I think “until the tail clears the bow.”

I have my hands on the stick almost the instant the wheels are off the deck. Never had a takeoff failure once with the Hornet.

Now the Su-33–I’ve probably crashed it on takeoff MORE than on landing…

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After four days, the problem resolved itself just leaving a gash pilot as the remaining issue

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With at LEAST 9 confirmed kills last night!! Pilot skill doesn’t matter to the drivers of dead APC’S

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