Problem with Just Flight Pa-28 Arrow III

TL:DR - it’s a known characteristic of the Arrow, the nose wheel gets into an uncontrollable wobble. The trick is to start your takeoff roll around 60-65 knots before that kicks in.

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Ok thx, I will try.

Trim nose up for take-off, if you are flying at the default loading, the CG is towards the front of the allowed range. With both front seats occupied, our testers gave a trim position in real life somewhere in the aft half of the trim range (from memory, it was something like 9 turns forwards, 18 turns back to check full movement and then about 6 or 7 forwards from fully aft?) Something in the ground handling is odd when pressure is put on the nose wheel, and I haven’t been able to work out why.

Also check you are using the linear curves suggested and shown (screenshot) in multiple threads both here and on the JF forum. It will only fly how it is intended to if you use the same curves / sensitivities / dead ones it was developed with.

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It only really occurs with a strong enough crosswind. If the wind is directly on the nose no wobble is felt, no matter how long you leave it before rotating. There are a lot of threads on this, regarding crosswind, and static friction.

It just so happens that the Arrow suffers more from this than any other plane I fly. The Islander, by comparison, is far more stable on take-off roll, even with a stiff crosswind.

If all else fails, contact Just Flight’s support directly and they will hopefully help you get sorted out. Their forums are great resources for questions like this as well.

Could you be more precise?
The issue others described does not kick in immediately when pushing the throttle but at around 60kt IAS shortly before you’d pull to rotate.
The way you describe it sounds like it’s a different issue if it happens immediately even at very slow speed and might really be crosswind.

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Yes, it is around rotation speed that it occurs. A video I shot before, for a related issue, showed that the crosswind was at maximum strength around 70kts, but the wobbles I felt from gusts were lower than that, closer to 41kts I think, but that was more down to an issue with Asobos implementation of gusts, which if I remember right doesn’t even exist in live weather but only occurs with manually configured weather.

Take off without gusts

Take off with gusts

In the non-gusty video you can see the nose wheel twitch come in around 75-76kts.

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Slight nose up trim before take off will help a lot.

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I had a flight today slight wind from the left but still it had a tendency to roll left. I had a same sized copilot with me and used the left tank first so I can’t really understand it especially as I was levelled out and taking it easy … VFR no auto pilot

When airborne, the wind has no effect on your roll, it’s pushing the whole aircraft along with the air mass.

Edit: Except for sudden up-/downdrafts and turbulences which of course might affect your roll :slight_smile:

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Yep, I had about 5 degrees up, and it makes a big difference. It really doesn’t like riding its nose wheel. :slight_smile:

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I always set trim for takeoff. Didn’t have time today to fly, but when I do I will try what above is mentioned.

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If trim is not positioned back as @GrimPhoenix9349 suggested, it will happen wind or no wind. But you are correct it’s even worse with a crosswind. Which makes some sense, since, if the tire friction suddenly goes to zero, and the wind suddenly takes affect, it stands to reason a sudden wild swing will ensue.

Pull back on the elevator trim a bit, and, as @FlyMe2Dunoon suggested, start to pull up slightly to get the nosewheel up at around 60 - 65 knots. After a few tries, you’ll find the correct trim position for takeoff.

TBH, even when I fly the Warriors I rent, it really does perform better with a little up elevator trim on takeoff. If I forget, it can be hard to get it off the ground. I don’t get the wild swings, obviously, but, Asobo seems to think this is due to their tire friction model, on/off and all that.

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Well at least I’ve got a copilot now :wink:

Wind shear can also be freaky in real life. Not sure how well it is modelled in game though.

I assume you mean in the sim?

In real life, there’s plenty of times I’ve been flying along and a gust comes along and tries to flip me over, IOW, induces a sudden roll. It’s kind of a bummer when it happens when you’re looking down and focused on changing frequencies. :wink: Wah!

Some of my earliest flights last August were around the Grand Canyon. If you fly parallel to the canyon walls, you can decide whether you want to experience a down draft, or up draft. There is a very pronounced roll felt. I may be remembering this wrong, but it felt sufficiently nuanced that I could decide which wing it would strike, and anticipate which way the plane would roll.

Coming from X-Plane, that just about knocked my socks off! :slight_smile:

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You’re all talking about turbulences (lateral/vertical).
I was referring to constant wind (they were talking about “slight wind”) which doesn’t induce a roll. :slight_smile:

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A bag of cement under the passenger seat should help with the roll, a bit like my old Triumph Stag only that was in the boot to keep the wheels on the ground. (boot = trunk for you Americans) :grinning_face_with_smiling_eyes:

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Actually pre SU4 we had wind shear and wind gusts but sadly this is not working since then… it’s long lasting bug now…