What’s a good trim at landing

[ruddy122]

I’m used to very small inputs around the deadzone which was throwing me off

I decreased the deadzone so the computer could register my inputs

It works for the DCS Hornet but too sensitive for the DCS T-45

Hornet Drivers we’re talking about a page you can see the trim is set to

But 11 NU is a good trim place to start and I was fighting the FBW

Thank You for the tips


Sent from my iPhone using Tapatalk

[Lex Talionis]

FBW or not, all aircraft (from f18s to C152s) seek the AOA/AS it is trimmed for. It is a fundamental aerodynamic reality of longitudinal stability. The skill set talked about works for the 45 (and should for all aircraft where the pilot is responsible for trimming the aircraft) with the understanding that, each aircraft will have some nuance regarding the aplitude and duration of the oscillations undergone as the airframe seeks equilibrium. 

 

I would highly recommend watching the vid posted earlier, all of this will be explained with exercises to practice the skill set. (Had no idea people still used it)

 

You can see the position of each control surface on the fcs page. But if you know how to trim properly (pilot sh!z 101) it isn't really needed.

 

There is lots to be talked about on the subject.  It can be quit counterintuitive when trying to wrap your head around it on your own. Your not the first and will certainly not be the last wrestling with this. 

 

Good luck, hope it helps.

Edited July 21, 2021 by Lex Talionis

[Frederf]

Slowing to on-speed throttle is relaxed and you pull back on the stick as needed to maintain VV position as AOA evolves toward the target value. Trim can be introduced to replace the majority of held back stick. When AOA is within a small gap to target value then relax all remaining back stick and trim switch only to achieve target. VV may sink or climb but don't try to arrest it with stick which would prevent your trim setting. If you have spare brain time during this process use throttle to adjust VV relative to horizon. It's much more important to set hands off trim AOA equal to target than it is to keep VV on horizon. If you aren't confident that hands free = target AOA then the remaining approach is wasted effort.

 

I would say that's ballpark technique. You apply stick back pressure while slowing and trim is introduced to replace this back pressure. Trim is not used to fly the airplane. Whatever stick input is needed comes first. Second you run trim opposite to pressure. As trim takes effect you relax this stick pressure in a way that you feed out as much pressure as trim is applying for you. Trim change is the reaction. Your stick relaxation is the reaction in equal measure. Video of HUD shouldn't be able to tell anything is happening.

 

Once AOA is set then theoretically all flight path angle is done with throttle. This can be very sluggish like trying to control pitch in an airliner up and down by a fat man running along the aisle forward and backward in the seating area. Unless you're super smooth and have excellent anticipation throttle alone is impractical. Pitch control can be made sharper in time with some stick input. However over long term stick must be returned to neutral and long term flight path change taken over by throttle.

 

 

[HILOK]

1 hour ago, Frederf said:

Slowing to on-speed throttle is relaxed and you pull back on the stick as needed to maintain VV position as AOA evolves toward the target value. Trim can be introduced to replace the majority of held back stick. When AOA is within a small gap to target value then relax all remaining back stick and trim switch only to achieve target. VV may sink or climb but don't try to arrest it with stick which would prevent your trim setting. If you have spare brain time during this process use throttle to adjust VV relative to horizon. It's much more important to set hands off trim AOA equal to target than it is to keep VV on horizon. If you aren't confident that hands free = target AOA then the remaining approach is wasted effort.

 

I would say that's ballpark technique. You apply stick back pressure while slowing and trim is introduced to replace this back pressure. Trim is not used to fly the airplane. Whatever stick input is needed comes first. Second you run trim opposite to pressure. As trim takes effect you relax this stick pressure in a way that you feed out as much pressure as trim is applying for you. Trim change is the reaction. Your stick relaxation is the reaction in equal measure. Video of HUD shouldn't be able to tell anything is happening.

 

Once AOA is set then theoretically all flight path angle is done with throttle. This can be very sluggish like trying to control pitch in an airliner up and down by a fat man running along the aisle forward and backward in the seating area. Unless you're super smooth and have excellent anticipation throttle alone is impractical. Pitch control can be made sharper in time with some stick input. However over long term stick must be returned to neutral and long term flight path change taken over by throttle.

 

with respect to power approach, that may be the best wrap-up of whats going on in our current dcs hornet - loving the metaphore with the airliner

[TimRobertsen]

19 hours ago, ruddy122 said:

I get the AOA but can’t keep it for long any tips

If you set the AOA, and it then starts drifting, this might be the cause:

(If not, it could be a bug)

 

 

[ruddy122]

I figured it out thanks for the advice and how the DCS Hornet works and the real Hornet works for me I set the deadzone too high and my small inputs in roll and pitch were ignored by my computer so I was surprised when the computer registered a larger input

Second practice, practice, practice

Third you have to be more precise than the USAF way

The USAF way is land between the two white lines 1000 to 3000 down for the KC-10

I really admire the brave Hornet dudes and dudettes that arrive safely in Case III at night, bad weather and the boat swaying

It would scare me


Sent from my iPhone using Tapatalk

[AndyJWest]

8 hours ago, Frederf said:

...If you have spare brain time during this process...

 

Sadly, I seem never to have any to spare. Can I download more from somewhere? 

[oldcrusty]

38 minutes ago, AndyJWest said:

 

Sadly, I seem never to have any to spare. Can I download more from somewhere? 

 

Sorry, I'm out.  Hey, not that far in the future, who knows...  I stocked up on aluminum foil already.

[HILOK]

31 minutes ago, AndyJWest said:

 

Sadly, I seem never to have any to spare. Can I download more from somewhere? 

 

try that: [assuming you are in thrust idle, gear down, flaps full, level flight] when you see the E bracket clearly fall, hold trim up and count 2 mississippis while slowly adding thrust...then hold your altitude solely using thrust...then fine tune your trim for E bracket centre

[Hulkbust44]

Slowing to on-speed throttle is relaxed and you pull back on the stick as needed to maintain VV position as AOA evolves toward the target value. Trim can be introduced to replace the majority of held back stick. When AOA is within a small gap to target value then relax all remaining back stick and trim switch only to achieve target. VV may sink or climb but don't try to arrest it with stick which would prevent your trim setting. If you have spare brain time during this process use throttle to adjust VV relative to horizon. It's much more important to set hands off trim AOA equal to target than it is to keep VV on horizon. If you aren't confident that hands free = target AOA then the remaining approach is wasted effort.
 
I would say that's ballpark technique. You apply stick back pressure while slowing and trim is introduced to replace this back pressure. Trim is not used to fly the airplane. Whatever stick input is needed comes first. Second you run trim opposite to pressure. As trim takes effect you relax this stick pressure in a way that you feed out as much pressure as trim is applying for you. Trim change is the reaction. Your stick relaxation is the reaction in equal measure. Video of HUD shouldn't be able to tell anything is happening.
 
Once AOA is set then theoretically all flight path angle is done with throttle. This can be very sluggish like trying to control pitch in an airliner up and down by a fat man running along the aisle forward and backward in the seating area. Unless you're super smooth and have excellent anticipation throttle alone is impractical. Pitch control can be made sharper in time with some stick input. However over long term stick must be returned to neutral and long term flight path change taken over by throttle.
 
 

With a little practice it's pretty easy to learn the throttle control anticipation. I never touch pitch controls once in landing configuration, unless I'm doing a section landing as -2.

Mobius708

[cdrkrotchetyusn]

no curves for the Curveball, or deadzone, either:

 

 

[Derbroomaster]

On 7/20/2021 at 9:14 PM, Nealius said:

"8.1° AoA" gets thrown around a lot when people ask about landing trim, and that is correct, but not applicable to what is being asked. 8.1/on-speed doesn't happen until after trimming. Landing trim questions are asking about the trimming process itself, before you arrive at 8.1/on-speed."

 

 

Bless you. A thousand times, bless you.

[Brun]

I'm often not sure whether people understand that trim is simply an offset to stick position.

 

It's perfectly possible to be significantly out of trim but on-speed and correct AOA,  it just means that you'll need pressure on the stick to maintain it. The benefit of being correctly trimmed is that the aircraft will maintain its attitude with the stick in a neutral position.

[Nealius]

1 hour ago, Brun said:

I'm often not sure whether people understand that trim is simply an offset to stick position.

 

That and highly-technical hobbies like ours tends to attract people who aren't the best at communicating, not grasping what the question is asking, and then parroting off a rote-memorized stat or procedure without thinking beyond the surface.

Edited July 23, 2021 by Nealius

[Barra1]

There isn’t really a ball park number because it depends on aircraft weight. I’ve noticed after completing a carrier trap the stabiliser is set at 16 but this was a low fuel state and still carrying AA weapons. I suggest practice flying around at altitude and at low speed so you get a feel for on speed AOA without worrying about hitting the ground. I tend to find a sweet spot at around 136-141 knots where I can get her nice and stable on a three degree glide slope and on speed at correct AOA. Practice, practice and more practice I’m afraid.