Why is tanker in constant bank and unstable altitude in precontact

[DmitriKozlowsky]

Having devil of a time inflight refueling. Basically the tanker is always banking, and altitude is chaotic after tanker reports "Return Pre-Contact".

Aren't tanker suppoused to straighten their flight path and hold altitude during precontact ?

[DmitriKozlowsky]

OK. Obvious to me, that I am kind of clueless, about what the sight picture of tanker should be in pre-contact , and how to hold that position. As tanker comply won't stick the thingy into the receptecale. What I find confusing and frustrating is why the drogue is alover the place. Including inside yhe cockpit at times. Why is the tanker not steady?

[razo+r]

Okay, so this not an official tanker, so things may not behave as expected. Rather take the official one to make sure it works.

Then, check how the tanker is set up. If it is tasked to circle, it will never straighten out. Let it switch between two waypoints if you want him to fly straight segments.

And once you are in the pre-contact position, make sure to tell him "ready contact" and the tanker clears you for contact. Only then will the boom connect to you.

Edited February 25 by razo+r

[BuzzU]

Do you really need the tanker in the A-10C?

[Yurgon]

I'd normally say "Track or it didn't happen", but as razo+r pointed out, this does not look like a tanker from the DCS assets, and the first thing to do in such cases is to either seek help from the mod developer, or remove and preferably uninstall the mod to make sure it doesn't mess anything up.

If the same issue happens with the DCS KC-135, upload a track so we can see what actually happens.

13 minutes ago, BuzzU said:

Do you really need the tanker in the A-10C?

Good point.

But it has on occasion come in handy, taking an additional sip of gas.

[BuzzU]

1 hour ago, Yurgon said:

I'd normally say "Track or it didn't happen", but as razo+r pointed out, this does not look like a tanker from the DCS assets, and the first thing to do in such cases is to either seek help from the mod developer, or remove and preferably uninstall the mod to make sure it doesn't mess anything up.

If the same issue happens with the DCS KC-135, upload a track so we can see what actually happens.

Good point.

But it has on occasion come in handy, taking an additional sip of gas.

Take a bigger gulp before you leave.

[jaylw314]

13 hours ago, DmitriKozlowsky said:

OK. Obvious to me, that I am kind of clueless, about what the sight picture of tanker should be in pre-contact , and how to hold that position. As tanker comply won't stick the thingy into the receptecale. What I find confusing and frustrating is why the drogue is alover the place. Including inside yhe cockpit at times. Why is the tanker not steady?

This looks like the KC10 from the Military Aircraft Mod, which is known not to work.

[DmitriKozlowsky]

19 hours ago, BuzzU said:

Do you really need the tanker in the A-10C?

I got original A-10C in 2013. My second DCS mod after DCS: KA-50. For twelve years I ignored or stayed away from learning fixed wing inflight tanking. For me it is impossible in AV-8B mod. Likewise looks incredibly difficult in A-10CII. 

Couple of tasks that I am simply unable to do. 

1. Unable to remain stable at same speed and altitude as tanker. Once joined up, the relative position of my aircraft and tanker dances crazily across screen. Speed is either 1 or 2 knots too fast or too slow. Nose either creeps up or creeps down. Now matter how fine my X56 throttle movement is, I am unable to find hold constant zero relative speed to tanker. Can't do it. After hundreds of hours of practice, not happening. I want to blame resolution resolution of my HOTAS, but figure others would have same issue. I don't see that in forums.

2. In 2D view, I am unable to judge accurate distance between and closure rate of own A/C and tanker when up close n pre-contact. I fail to find that magic 'sight picture' of tanker with respect to HUD frame.

3. To my, from my POV, it looks like tanker itself has erratic altitude. Often, up close, the probe is often inside my cockpit. That tells me that there is a DCS issue of position and collision detection in DCS.

4. Tanker turns and banks without warning , or in posted case is always in bank and turn , despite ME Task of Refueling. As I don't quite understand or predict tanker behavior, I cant tell what is happening.

So I gnored that part of DCS.

Now I gotten back to it. But not quite up to the challenge of the task.

Edited February 26 by DmitriKozlowsky

[razo+r]

8 minutes ago, DmitriKozlowsky said:

I got original A-10C in 2013. My second DCS mod after DCS: KA-50. For twelve years I ignored or stayed away from learning fixed wing inflight tanking. For me it is impossible in AV-8B mod. Likewise looks incredibly difficult in A-10CII. 

Couple of tasks that I am simply unable to do. 

1. Unable to remain stable at same speed and altitude as tanker. Once joined up, the relative position of my aircraft and tanker dances crazily across screen. Speed is either 1 or 2 knots too fast or too slow. Nose either creeps up or creeps down. Now matter how fine my X56 throttle movement is, I am unable to find hold constant zero relative speed to tanker. Can't do it. After hundreds of hours of practice, not happening. I want to blame resolution resolution of my HOTAS, but figure others would have same issue. I don't see that in forums.

You don't need constant 0 relative speed. You can have 1-2 knots more or less, some movement of you is okay. Important is only that you stay within the limits of the boom. And in the end it will be a matter of practice. The more practice you get, the better you will be.

And remember, pilots get hundreds of hours learning how to fly properly before they learn aerial refueling, so that helps too.

8 minutes ago, DmitriKozlowsky said:

2. In 2D view, I am unable to judge accurate distance between and closure rate of own A/C and tanker when up close n pre-contact. I fail to find that magic 'sight picture' of tanker with respect to HUD frame.

Perhaps try to focus on something different than the HUD frame, perhaps that helps. Everyone is different and has his own technique that works for him. Once you get contact, remember that sight picture, it will help you in the future.

8 minutes ago, DmitriKozlowsky said:

3. To my, from my POV, it looks like tanker itself has erratic altitude. Often, up close, the probe is often inside my cockpit. That tells me that there is a DCS issue of position and collision detection in DCS.

That either means you were too fast for the boom, in the wrong position or not yet cleared for contact. Tanker itself should stay perfectly straight, so it's mostly you.

And yes, the collision detection is not perfect. If it were, you would have more issues than currently.

8 minutes ago, DmitriKozlowsky said:

4. Tanker turns and banks without warning , or in posted case is always in bank and turn , despite ME Task of Refueling. As I don't quite understand or predict tanker behavior, I cant tell what is happening.

So I gnored that part of DCS.

Now I gotten back to it. But not quite up to the challenge of the task.

Like I said previously, if he constantly banks, you have to change the setup of the tanker. He will not straighten out just because you want to refuel.

Unannounced turns however is just how it is in DCS. We're still waiting for ED to improve it.

In the end, it's simply a practice thing. We cannot tell you more than practice, practice, practice and watch tutorials. If you however would attach some short tracks (without mods), we could tell you more accurate tips for you.

[DmitriKozlowsky]

This is typycal of what happens. Up close at the tanker, KC-135 stock, its chaos. Tanker is up and down, boom is all over the place, speed is not steady. I can't hold the aircraft with such precision as to be within 1 foot of alt and 1 knot of speed. No matter how fine my controls are. Pretty sure that tanket itself is not at constant speed and altitude. Anway, I have no clue as what is happening, what I am doing wrong, thus I am clueless as to what I should do.

A10CII_failedInflightRefuel.trk

[razo+r]

13 minutes ago, DmitriKozlowsky said:

This is typycal of what happens. Up close at the tanker, KC-135 stock, its chaos. Tanker is up and down, boom is all over the place, speed is not steady. I can't hold the aircraft with such precision as to be within 1 foot of alt and 1 knot of speed. No matter how fine my controls are. Pretty sure that tanket itself is not at constant speed and altitude. Anway, I have no clue as what is happening, what I am doing wrong, thus I am clueless as to what I should do.

A10CII_failedInflightRefuel.trk 6.23 MB · 1 download

The Tanker is rock solid, perfectly stable. The only things that is chaotic is you. The Tanker varies 1m inbetween 30 seconds, and 0kph/kts in that time.

You on the other hand... You are all over the place...

Some things may help: Increase the speed of the tanker. 170kts is rather slow. Put it up to like 200 or 220, that will help a bit in terms of control response.

Trim your aircraft. Make sure that when you are at the tankers speed, you have trimmed your aircraft.

Airbrakes are personal preference. With them out, the speed will react quicker, but that means you also have to react faster. 

Your flying is quite erratic. You have big throttle movements and you never fly level, you are all over the place. Try perhaps learning some basics first. For example your speed, you can practice it quite simple. Engage Alt Hold and aim for lets say 220kts. Once you can hold that perfectly for lets say 10 seconds, change it to a different speed and hold it for another 10 seconds and then change the speed again. Make fine throttle adjustments. The closer you come to the speed, the smaller the throttle movements. And you don't have to go full throttle until you are at the speed and then go idle. Once you get closer, slowly take out or give power, ever so slightly more or less.

Then once you can hold the speed, disengage the autopilot and fly level. Once you got that, keep your speed and climb or descent to a different altitude all while maintaining the speed. Once you are level, change speed and altitude. 

Once you learned the basics of flying, tanking will be simply, as you just have to stay at the same speed and level, two pretty basic things. But if you can't even do that, tanking will be impossible.

[DmitriKozlowsky]

Thats about as fine a control as I have in A-10CII with my X56. My curves are somewhat flat at 35 for pitch and roll axis.

[jaylw314]

12 hours ago, DmitriKozlowsky said:

Thats about as fine a control as I have in A-10CII with my X56. My curves are somewhat flat at 35 for pitch and roll axis.

You don't need super fine controls--some guys do it with Xbox controllers.  Don't try to hold a small deflection, just briefly tap the stick in that direction and do it repeatedly.  If you need more, tap faster, don't move the stick farther, that just invites overcontrolling.

And yes, 170 KIAS is super slow.  Tanker speed should be set to 220 KIAS, which equates to between 280-300 knots groundspeed in the Mission Editor.

[Yurgon]

On 2/25/2025 at 1:15 PM, DmitriKozlowsky said:

Aren't tanker suppoused to straighten their flight path and hold altitude during precontact ?

No and yes.

IRL, tanking on a straight path or tanking in a racetrack orbit is determined, scheduled and briefed before the flight.

As far as I'm aware, tankers should always hold altitude during refueling.

In DCS, tankers will follow their waypoint actions, and most tankers in DCS are set up to fly a racetrack between 2 waypoints. The angle of bank during the racetrack turns should (since a few updates ago) be a solid 30 degrees, regardless of tanking or not.

As far as I'm aware, pilots won't get a heads-up from tankers in real life either before the tanker enters a turn, though the waypoint/location where such a turn is initiated may be known to the pilot of the receiver. It's up to mission designers to let pilots know about such details, but trained pilots won't really care whether or not the tanker is banking or not, as long as it's smooth. Not just for giggles, they demonstrated the B-52's capability to receive fuel at absurd tanker bank angles somewhere around 60ish degrees or so.

15 hours ago, DmitriKozlowsky said:

Once joined up, the relative position of my aircraft and tanker dances crazily across screen.

That is a picture book case of pilot induced oscillation. When you look at the tanker in the external view or in external tools like Tacview, it is indeed rock solid.

You are trying to maneuver your aircraft in 4 axis (pitch, roll, yaw, thrust) in order to be in a box roughly 5m by 5m by 5m (*) in size, yet you oscillate around 3 of those axis by multiples of that box.

(*) Actually I'm not sure how big the boom's constraints are; might be a lot less, might be a bit more. In either case, it's not a whole lot of leeway.

Aerial refueling is formation flying first and foremost. I would recommend to take a step back, learn the basics of formation flying first and only then come back to aerial refueling. Otherwise it's like taking a formula one racer and trying to compete with the world champion after successfully not crashing 3 laps in a row - it's not technically impossible, but very unlikely to yield a positive result without hours upon hours upon hours of training.

15 hours ago, DmitriKozlowsky said:

Now matter how fine my X56 throttle movement is, I am unable to find hold constant zero relative speed to tanker.

No one can. There is no one throttle setting that will get you to match the tanker's speed. Look at any documentary of aerobatics teams. Any pilot flying formation on another aircraft will move stick and throttle all the time. In most cases, the inputs will actually seem pretty big. But pilots will know to counter any input they make. Basically, it's a never-ending series of corrections and counter-corrections that - from the outside - look perfectly stable.

You're not the first virtual pilot to struggle with AAR, and you won't be the last. There are dozens of tips that pilots use. Some tips work well for certain pilots, some work well for others.  The forum should hold many of them.

More than anything, AAR comes down to practice. At some point it'll just click.

Edited February 27 by Yurgon

[DmitriKozlowsky]

"More than anything, AAR comes down to practice. At some point it'll just click."

After hundreds of attempts, it ain't. Same result.

Same issue as I have with landing and taking off in taildraggers in DCS. No matter how  much I try to rudder dance, I ground loop. 100% of the time. No exceptions. After hundreds of attempts, 3 months,I got zero right. So I threw out any hope for flying tail draggers. It just aint gonna happen. It did not help that most usefull advice I got is "You ain't doing it right".

[DmitriKozlowsky]

It would be helpfull if autopilot hdg/alt hold would work with refuel door open. I can then join up on tanker, find the sweet spot, engage the AP then just worry about throttle. But no, AP kicks off when door is open, and won't enage until closed.

Trim is kind of weird. Is there a perfect trim, where aircraft flies at constant alt and pitch. Seems to me that I can get close but never stable. A single tick of pitch trim either makes nose go up, or down, then correcting with counter single trim just reverses. But never hold it at zero VV. At tanker, its really pronounced.

[GGTharos]

6 minutes ago, DmitriKozlowsky said:

It would be helpfull if autopilot hdg/alt hold would work with refuel door open. I can then join up on tanker, find the sweet spot, engage the AP then just worry about throttle. But no, AP kicks off when door is open, and won't enage until closed.

No, it won't work because:

6 minutes ago, DmitriKozlowsky said:

Trim is kind of weird. Is there a perfect trim, where aircraft flies at constant alt and pitch.

No, this is completely dynamic. 

6 minutes ago, DmitriKozlowsky said:

Seems to me that I can get close but never stable. A single tick of pitch trim either makes nose go up, or down, then correcting with counter single trim just reverses. But never hold it at zero VV. At tanker, its really pronounced.

You need to be stirring the stick and you have to anticipate what your corrections will do.   Lose a knot, nose drops, gain a knot, nose rises.

[DmitriKozlowsky]

This is impossible for me. I set tanker speed to 250 knts at 15K in ME. In mission it does 198, sometimes slowing down to 174. Up close. Something , wake turbulence, is throwing me side to side and up and down, when I am at tanker. In a second I find myself either on top or way below tanker, without stick deflection. I am unable to find the sweet spot of sight picture of boom  in HUD. Speed holding is a s**t show. Either too fast or too slow, retarding throttles, and aircraft still goes faster then tanker by a know or two. As usual the probe winds up inside cockpit or intersecting nose. Very confusing. Not to mention that HUD is washed out by clouds and sun, so I watch the steam gage for speed.  HUD is at max intensity. Overall terrible experience. 

Attempt #1XX something.

A10CII_failedInflightRefuel_take2.trk

Edited February 27 by DmitriKozlowsky

[Nealius]

8 minutes ago, DmitriKozlowsky said:

I set tanket speed to 250 knts at 15K in ME. In mission it does 198, sometimes slowing down to 174.

Speed in ME is TAS, not CAS. If you want 250kts at 15,000ft you need to program 311kts in the ME. (311KTAS @15k = 250KCAS).

But IIRC real tanker speeds for the A-10 are 220-230KCAS, which would be 274-286KTAS at 15k.

Edited February 27 by Nealius

[DmitriKozlowsky]

3 minutes ago, Nealius said:

Speed in ME is TAS, not CAS. If you want 250kts at 15,000ft you need to program 311kts in the ME.

OK, will give that a try. BTW, the ME speed is shown as ground speed. The checked off GS on the side. Which refuses to be unchecked.

[DmitriKozlowsky]

THis is nigh impossible. The tanker is not steady. I cannot be more stable then in this attempt. The probe goes ino nose or into cockpit. This is messed up. I set speed 315 knots. This translates to 249 knots IAS in mission at 15K. Tanker is not keeping that speed or altitude. I was finding myself with zero throttle, at below 190 knots IAS, and still overtaking the tanker. This appears to be an impossible task,. Maybe with VR, which I don't se. But that close to the tanker, I have no depth perception or closure rate. So there has to be lights, a guide or something. A magic HUD picture of where boom is suppoused to be. Otherwise this is not doable. Not by me.

A10CII_failedInflightRefuel_take3.trk

[Minsky]

1 hour ago, DmitriKozlowsky said:

THis is nigh impossible. The tanker is not steady. I cannot be more stable then in this attempt.

Do yourself a favor and disable the wake turbulence in DCS settings.

Then cycle through *all* tanker waypoints and set them to the same speed (I used 0.48 mach but that's just an arbitrary number).

Like other people already told you, the tanker is rock steady. Play your own track and watch tanker's airspeed and altitude using the F2 camera. Then look at yours.

Edited February 27 by Minsky

[Nealius]

Try 274kts GS (220KCAS). 250 is too hard for the Hog. 

In your replay track the tanker is keeping speed and altitude. You are not. The probe is going through the nose because you drift up out of position. Put the velocity vector on the tip of the probe and keep it there all the way in. 

1 hour ago, DmitriKozlowsky said:

So there has to be lights, a guide or something.

There are on the bottom of the nose of the tanker.

[DmitriKozlowsky]

Velocity Vector on probe tip is the first thing I tried and kept on doing. It does not work for me upclose at the tanker. Motion is crazy, and I have no control over it. Approaching the tanker is not a problem, even if I am a little slow. Its up close, after I get 'Cleared Contact" or "Return Pre-Contact" that things fall apart. Its consistent. It happens every time. Regardless of what I do.

 

All waypoints for tanker are set to same altitude and same speed 315 GS. When I set it to 275  GS, the tanker flies at 200 IAS, and throws my aircraft crazy all around without warning, as I approach tanker. At 200 IAS, at 15K, A-10C feels like its balancing on head of pin, trying to tip over. In any case I have tanker that slows down, using its AI logic, to below 190. Then without warning, witin a second, before I can do anything, I am below it, and lost eyesight of boom.

[Minsky]

54 minutes ago, DmitriKozlowsky said:

Motion is crazy, and I have no control over it.

I had the same problem until I fixed tanker waypoints (contrary to what you say, they were NOT set to same speed) and re-saved the mission without wake turbulence.