Nealius Posted January 9, 2018 Posted January 9, 2018 Roll from an asymmetric load I'm familiar with, but in the A-10C, AJS37, and M2000C I have never experienced yaw from an asymmetric load. For some reason I do in the AV-8B. I have training payloads with a TCTS pod on the right wing and CAP-9M on the left wing. I need quite a bit of left trim to counteract the roll induced by the TCTS pod, but I also noticed right yaw, requiring just a touch of left pedal to properly track my heading. The analog slip indicator is centered despite this constant yaw. This is in zero wind conditions, and does not happen with a symmetric load, or a clean jet. Is this normal?
winchesterdelta1 Posted January 9, 2018 Posted January 9, 2018 Yes this is normal. Go in close, and when you think you are too close, go in closer.
boedha68 Posted January 9, 2018 Posted January 9, 2018 Roll from an asymmetric load I'm familiar with, but in the A-10C, AJS37, and M2000C I have never experienced yaw from an asymmetric load. For some reason I do in the AV-8B. I have training payloads with a TCTS pod on the right wing and CAP-9M on the left wing. I need quite a bit of left trim to counteract the roll induced by the TCTS pod, but I also noticed right yaw, requiring just a touch of left pedal to properly track my heading. The analog slip indicator is centered despite this constant yaw. This is in zero wind conditions, and does not happen with a symmetric load, or a clean jet. Is this normal? The AV-8B has a light airframe. Every bombdrop or firing a maverick has a huge impact of stabilizing the plane. It's a real challenge too fly it. :D Newest system: AMD 9800X3d, Kingsting 128 GBDDR5, MSI RTX 5090(ready for buying), Corsair 150 Pro, 3xSamsung 970 Pro, Logitech X-56 HOTAS, Pimax Crystal Light (Super is purchased) ASUS 1200 Watt. New system:I9-9900KS, Kingston 128 GB DDR4 3200Mhz, MSI RTX 4090, Corsair H150 Pro RGB, 2xSamsung 970 EVO 2Tb, 2xsamsung 970 EVO 1 TB, Scandisk m2 500 MB, 2 x Crucial 1 Tb, T16000M HOTAS, HP Reverb Professional 2, Corsair 750 Watt. Old system:I7-4770K(OC 4.5Ghz), Kingston 24 GB DDR3 1600 Mhz,MSI RTX 2080(OC 2070 Mhz), 2 * 500 GB SSD, 3,5 TB HDD, 55' Samsung 3d tv, Trackir 5, Logitech HD Cam, T16000M HOTAS. All DCS modules, maps and campaigns:pilotfly:
26-J39 Posted January 9, 2018 Posted January 9, 2018 Is this behavior specific to the AV-8B? Its more pronounced in the AV-8B as it's a very small and light airframe.
tempusmurphy Posted January 9, 2018 Posted January 9, 2018 Makes sense to have some yaw.... Not only do have more weight on the side with weapons left but also drag from the weapons
rinao0o Posted January 9, 2018 Posted January 9, 2018 Roll input to the left gives you a bit of aileron induced adverse yall to the right, plus drag induced yaw from the pod, you'll get 2 source of that same direction yaw moment which might be prominent enough to causes problem, try to counter it with something on the wing hardpoints.
Kula66 Posted January 9, 2018 Posted January 9, 2018 Seems much more pronounced in the Av-8B than in the F-5, an aircraft with a similar weight ... perhaps the F-5 doesn't carry quite the same load out on the wings?
Kang Posted January 9, 2018 Posted January 9, 2018 I'd assume the F-5's shorter wingspan also means the moment of rotation from the difference in drag is slightly smaller.
Lithion Posted January 9, 2018 Posted January 9, 2018 I've recently noticed this as well on the Viggen, with the jammer/dispenser being assymetric it'll induce some yaw T.16000m HOTAS + Pedals || TrackIR5 || Win10 64bit || 120+500GB SSD, 1TB HDD || i5 4440 @3.3GHz || 16GB RAM @ 1600MHz || GTX1070 G1 || FCIII, L39ZA, AJS-37, Normandy '44, Persian Gulf, Channel F/A-18C, Bf-109 K-4, WW2 Asset Pack, CA, P-47, F-16
Nealius Posted January 10, 2018 Author Posted January 10, 2018 I haven't noticed it on the Viggen with the jammer/dispenser, but unlike the Harrier I can't see the Viggen's nose as a reference point.
MustanGrande Posted January 10, 2018 Posted January 10, 2018 You should also mind your Gs. Any high-lift/G-heavy maneuvers will cause your center of lift, (the spine of the plane) to try and pivot around your center of gravity. (Which will be offset towards the heavy wing.) Also, try to make any turns into the lighter wing if possible.
Nealius Posted January 10, 2018 Author Posted January 10, 2018 (edited) Something is weird here: TCTS pod = 137lbs CAP9 = 190lbs With the CAP9 on the left wing and TCTS pod on the right wing, I am getting right roll and right yaw. Shouldn't it be to the left? Another test: Left wing: GBU12 (798lbs) Right wing: TGP (661lbs) and TCTS (139lbs) My right wing is only 2lbs heavier than the left, yet I experience a lot of right roll/yaw. Are the weapons weights in the Mission Editor wrong or something? Edited January 10, 2018 by Nealius
Rexamus Posted January 10, 2018 Posted January 10, 2018 (edited) I think we need to take into account moments (turning effect around a pivot). Or relative position of the wieght to the point of balance (fulcrum). 2lbs of difference will have a larger effect the further outboard it is. Are you stores on the same position either side? You could have 800lb on both wings, but, if 800lb is on the inboard left and your 800lb right hand is spread out over all 3 stations, you have pushed the wieght further away from the center of the aircraft, increasing the moment (turning effect) to the right hand side. Edit: the same effect can happen in yaw due to differences in drag of different stores and thier relative positions on the aircraft. Edited January 10, 2018 by Rexamus
Nealius Posted January 10, 2018 Author Posted January 10, 2018 In the first case, they are both on outboard stations. Yet despite the left being heavier, I experience right roll and yaw. In the second case, the GBU12 and TGP are on inboard stations, with the TCTS pod being on an outboard station.
Rexamus Posted January 10, 2018 Posted January 10, 2018 In the second case I would say it is turning effect of the spread load on the right wing and higher drag on the right wing. The right yaw probably also inducing a right roll. Not so sure whays happening in the first. I'll have a try when I get home later.
Lithion Posted January 10, 2018 Posted January 10, 2018 I haven't noticed it on the Viggen with the jammer/dispenser, but unlike the Harrier I can't see the Viggen's nose as a reference point. OT, but i noticed it because of the Nav system being so clear in the HUD T.16000m HOTAS + Pedals || TrackIR5 || Win10 64bit || 120+500GB SSD, 1TB HDD || i5 4440 @3.3GHz || 16GB RAM @ 1600MHz || GTX1070 G1 || FCIII, L39ZA, AJS-37, Normandy '44, Persian Gulf, Channel F/A-18C, Bf-109 K-4, WW2 Asset Pack, CA, P-47, F-16
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