Strong pitch up on flare when landing light

[escaner]

I find this aircraft a joy to fly, very easy, but it tries to kill me everytime when landing with low weight.

 

When I chop the throttles and pull a bit to flare, the aircraft gets a strong pitch up tendency that I need to counter with almost full fwd stick. The first couple of times this happened I did a go around. Now I am already expecting it.

 

E.g., yesterday happened again, the load being 1 x TGP, 1 x ECM pod, 1 x GBU-12 and 1,000 lb of fuel. Gear down, full flap, airbrakes in, flying the AoA indexer (about 112 KCAS), aircraft trimmed for the approach.

[Gliptal]

I think it's ground effect, something that was added only recently. It's particularly strong in the NTTR map (because of the higher temps?).

 

Please bare with me linking Wikipedia as a source: https://en.wikipedia.org/wiki/Ground_effect_(aerodynamics)

[Gierasimov]

I am using DCS:A-10C since 2010...

 

I find this aircraft a joy to fly, very easy, but it tries to kill me everytime when landing with low weight.

 

When I chop the throttles and pull a bit to flare, the aircraft gets a strong pitch up tendency that I need to counter with almost full fwd stick. The first couple of times this happened I did a go around. Now I am already expecting it.

 

E.g., yesterday happened again, the load being 1 x TGP, 1 x ECM pod, 1 x GBU-12 and 1,000 lb of fuel. Gear down, full flap, airbrakes in, flying the AoA indexer (about 112 KCAS), aircraft trimmed for the approach.

 

Wait, what? Ground effect? I want one, why don't I experience this?

 

On a serious note, I would check with airbrakes off and and trim reset. My landing speed is 120 KIAS when landing clean with approx 2000lbs fuel and head wind around 6m/s.

 

Ground effect lesson:

 

@Gliptal - do you know if it was documented that in fact DCS implementation of ground effect exists ??

Edited October 5, 2016 by Gierasimov

[GurbY]

I think it's ground effect, something that was added only recently. It's particularly strong in the NTTR map (because of the higher temps?).

 

Please bare with me linking Wikipedia as a source: https://en.wikipedia.org/wiki/Ground_effect_(aerodynamics)

Must be, although I personally think it's a bit exaggerated compared to the IRL ground effect. Especially on the NTTR map it is sometimes almost impossible to make a smooth landing.

[escaner]

Ground effect does not make a plane to pitch up as if the pilot was yanking the stick to his belly. It is an increase in lift that makes the plane float. Thermal soaring from heat has nothing to do with that, but the effect would be similar (plus some turbulence).

Anyway, this landing was at Caucaus at night...

[Gliptal]

@Gliptal - do you know if it was documented that in fact DCS implementation of ground effect exists ??

Nope, I can't recall ever reading an official statement about it. I do remember a thread discussing it though.

[Pocket Sized]

Try it again with full and then empty gun ammo.

 

It has a huge effect on center of mass, especially noticeable during takeoff and landing.

[Gierasimov]

My thoughts exactly

 

Ground effect does not make a plane to pitch up as if the pilot was yanking the stick to his belly. It is an increase in lift that makes the plane float. Thermal soaring from heat has nothing to do with that, but the effect would be similar (plus some turbulence).

Anyway, this landing was at Caucaus at night...

 

I don't recall this from 1.5, I use 2.0+ NTTR but I don't have this effect... Gun full, gun empty, no difference for me or is it that I am skilled enough to counter this effect without thinking of it?

[Gliptal]

I personally noticed it doesn't always happen. Sometimes I get it, but most times I do not.

[Pocket Sized]

I personally noticed it doesn't always happen. Sometimes I get it, but most times I do not.

 

See my post about gun ammo.

[escaner]

I don't remember the other times this happened to me, but this very last time all the gun ammo was expended. Will try again with ammo.

[SCU]

This happened to me more than a couple of times, sometimes with ammo sometimes without (I think mostly without though can't really remember I'm not really simming much these days). And no it wasn't ground effect, it was a full on aggressive pitch up exactly the same as when you yank the stick considerably backwards, literally.

[Pocket Sized]

As I said earlier gun ammo has a massive and very noticeable effect on takeoff + landing.

 

Also the elevator has very little down deflection available meaning it will require a good amount of forward stick to stop nose rising in an aft CG landing flare.

[NineLine]

Perhaps post vids or tracks showing what is happening with description of loadout and such.

[Xavven]

Guys, this is a bug, not ground effect:

 

https://forums.eagle.ru/showthread.php?t=154630&highlight=landing+flare

 

I've even experienced it in 1.5. A friend of mine didn't believe me and told me it was ground effect, but you can tell whether it's the bug or ground effect by opening your control position window (default is rctrl-enter) and watching your trim go crazy when you begin your round-out.

[Gierasimov]

Must have been fixed by now...

 

Guys, this is a bug, not ground effect:

 

https://forums.eagle.ru/showthread.php?t=154630&highlight=landing+flare

 

I've even experienced it in 1.5. A friend of mine didn't believe me and told me it was ground effect, but you can tell whether it's the bug or ground effect by opening your control position window (default is rctrl-enter) and watching your trim go crazy when you begin your round-out.

 

Seriously, what is wrong with my version? I cannot reproduce this effect at Nellis. I don't have the 1.5 installed so i can't check there...

 

So if it is not there for me, can't be a bug then right? I mean how could it affect just some of us?

[SCU]

Seriously, what is wrong with my version? I cannot reproduce this effect at Nellis. I don't have the 1.5 installed so i can't check there...

 

So if it is not there for me, can't be a bug then right? I mean how could it affect just some of us?

 

In my case it doesn't always happen & I at least wasn't able to pinpoint the exact reason why it happens or how to reproduce it.

[Livers]

I just flew the evening Takeoff mission in the latest update, stock loadout. Did the route and then flew over the lake, then north a bit. I told the wingman to RTB, then I followed him in. This is the first I can remember it ever happening to me, and it was dramatic.

[Nu-NRG]

This happened to me more than a couple of times, sometimes with ammo sometimes without (I think mostly without though can't really remember I'm not really simming much these days). And no it wasn't ground effect, it was a full on aggressive pitch up exactly the same as when you yank the stick considerably backwards, literally.

And it happens just past the runway threshold. That I was able to determine in the times that I experienced it. Which is as you say, completely random.

 

Me and some of our members spent some time analyzing tacview recordings as we landed in 4 ship trail. All of us experienced it as sudden jolt up, some to severe (go around) and some really subtle.

 

Tacview recordings showed a steady descent slope (little breaks, flaps, gear, on speed) and just on the threshold, that perfect line of descent goes in to curve. ACFT gains altitude, while still maintaining speed with no AoA change :D:joystick::joystick:

 

Happened on LSV and INS.