mushy behavior upon touchdown
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Somehow, the aircraft's nose is reluctant to come down upon touchdown. Instead, the nose stays in the air unless I push down the yoke. Should it not be the opposite, that is, the nose want to hit the runway unless the yoke is pulled up.
Given the very touch pitch dynamics, one is forced to reduce the control pitch sensitivity, which on landing decreases elevator authority. One compensates this lack of elevator authority with trim. This combination, however, results in the nose not wanting to hit the runway. -
@flyforever This is not a traditional aircraft like what you may be used to. The elevators are not moved directly through the column - but rather through flying tabs. This makes control authority very positive on the real aircraft - so much so that old school pneumatic artificial feel system had to be engineered into the control system (Look up Q-Pot).
While in sim it may come across as you having to "pitch down" - think of it more of slightly releasing the back pressure. Of course there will be improvements made to the flight model as things go along - but the behavior we are seeing in sim I feel is largely indicative of how the actual aircraft handles.
As a interm solultion I suggest you simply don't trim as far back on the approach - or don't be afraid to stabilize your approach with a little nose-down trim input.
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@flyforever I think this is an MFS flightmodel side effect. The Islander has it as well and the Kodiak had it for a long time until it got fixed after the last big FM update
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I'm trying to adjust my j/s curves to make the pitch up less sensitive to try and reduce my flare. The manual states the the nose should be just above the horizon at touchdown and I think I was causing too much pitch up.
In addition I've configured a button on the stick to toggle spoilers so I can deploy the airbrake just before touchdown and settle sooner.
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@b3lt3r Nice!
Yes, you should definitely have the air brake out at a minimum when crossing the threshold.
The spoilers are not automatic they need to be deployed manually - and they won't deploy if you have the speedbrake handle all the way back to the lift spoiler detent before landing. So keep that in mind.
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@plhought Hi! When I toggle the spoilers it does seem to deploy the brake fully and once I get down I see the lift spoiler display illuminate and copilot announces green and yellow seen. I think it's working as I want. If I could figure out how to make sky-dolly work accurately I could say for sure :-)
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@b3lt3r Well. If I'm sat on the ground and toggle spoilers, the airbrake deploys and both spoilers come up. However, when I do the same in the flare, if I go to chase view after a couple of seconds rollout I see the brake fully deployed but not the spoilers. They will not come up until I use the axis I have configured for the airbrake - then they pop up.
Confused because according to the manual the conditions are met - airbrake fully open and all 3 wheels compressed.
I want the button configured because the axis I use is on my stick and I need a 3rd hand to extend it safely :-)
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@b3lt3r What does the lever in the VC look like? Prior to weight on wheels I don't believe it can be moved into the spoiler deploy position even if you move your physical axis all the way, so on touchdown you have to wiggle it a bit to "update" it in my experience.
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@jmarkows ok. I think I may have it sorted.... I changed the button event to "send spoilers on" and pressed it twice in the flare. I had the callout for spoilers and when I went outside they were indeed up.
I'll try again tomorrow but this is looking good :-)
Thanks
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@b3lt3r So this was happening to me. What I figured out was while you are in the air, if you deploy full speedbrake it will NOT move into the spoiler detent. So even though on my bravo throttle, the axis is fully extended, it is not in the plane, Then I touch down and expected it to deploy, but if you move the spoiler axis slightly forward and then back, it will lock into the spoiler detent.
Your work around will also work, but just in case you need the keybind, you can still use the axis.
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@infamousaviator going to test again this afternoon. Occurred to me overnight that the only time I use that button is in the flare so I can just change spad to send the command twice in one event rather than press the button again. Let's see.
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In the real aircraft the spoilers would not "auto-deploy" like you are expecting - even with the lever in the far after spoiler detent.
This was done to prevent hard landing after bounces as the lift spoilers are very powerful on this aircraft.
What I typically do is extend the speedbrake axis to about 3/4 of the way - then pull it back that last bit after touchdown is "assured".
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@plhought Yes. I confirmed this yesterday. The only way I can make this work is to fully deploy the airbrake over the threshold with one press of the button and then press again after I'm actually down. It's still better than having to take one of my hands away from throttle or stick to jiggle the slider.
Thanks all.
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@b3lt3r That's actaully close to the real Aircraft. All things being equal, the Airbrake is fully opened at 100' AGL. This is done by pulling the handle back, it will physically stop short of the SPLR setting. Once you've touch down, you then pull the handle back to the SPLR position.
In a serviceable aircraft, it is not possible to deploy the Spoilers in the air. You could hang off the handle and it shouln't occur.
On later 146s and all RJs, there is an auto spoiler function. The spoilers will automatically deploy on landing once certain weight on wheels logic is satisfied.
