Experimental Formation Flying Training Mission for the A-10C

Hi all,

Most of you interested in formation flying probably get all the training/practice you need on MP, and so may not find this very useful. But for the rest of you, or for those of you interested in some SP practice, this mission might be interesting.

I am developing a Lua code library to support formation flying training. It is applicable to any two aircraft, AI or not. One aircraft is the lead, and the other is the wingman. They can be in the same or different groups, and there can be other aircraft in their respective groups.

Here, I present an example mission consisting of two A-10C's, the wingman of which is player controlled.

The task is to fly in formation with the lead, at a bearing of 45 degrees off lead's right and about 100 feet below (all these parameters are, of course, fully configurable either at start time through tweaking the mission script or during flight by the F10 radio command menu as described below).

    Lead
      ^
        \
         \
          ^ 
             Wingman

You will be scored on how well you keep formation position. Scoring weights keeping the correct line of bearing from lead the highest, followed by correct altitude below lead, followed by correct distance from lead. These scoring weights can be modified, of course.

Every so often, you will be told how to correct your position, with the following prioritization: first, correct you line of bearing; then your altitude; then your distance. This is following the advice of "The Formation Pilot's Knowledge Guide".

Radio commands available on the F10 menu allow you to:

(1) report your position in the formation: where the lead is, where you are in relation to the lead, and where you should be in the relation to the lead

(2) report the position of the lead from your current position

(3) report your score

(4) adjust the formation position: change the bearing from the starting of line abreast to trail to astern, on either side; change the altitude offset from the starting of -100 ft to any altitude, +/-, in relation to the lead; change the distance from lead from the starting of ~250ft;

(5) adjust the error tolerances of the bearing angle, altitude, and distance: greater tolerances allow for greater slop insofar as the instruction calls and scoring

(6) adjust the frequency of the instruction calls and the scoring

The actual flight path taken by the lead in this mission is deliberately simple: mostly straight and level with very few turns. Experienced formation flyers (or, probably, those who have mastered A2A refueling) will find this a breeze or maybe even boring. I do hope some of you will still try it out and give me some feedback on what needs to be improved/fixed. This is just an initial experimental release, and I am looking for feedback on how the script can be improved. Future releases will, of course, include some much more difficult situations (e.g., low-level if not quite NOE, fast, at night ...).

Future missions will also include other aircraft. In fact, when I first started this, my goal was to come up with a mission so that single-players could learn formation flying in the Huey. That still is my goal, but my formation flying library is flexible enough to handle any aircraft, as I said above, that I thought I would go for something a little easier to fly first to iron out the kinks.

So, if any of you have the time and inclination, especially those who are already experience formation flyers, please give this mission a try and tell me what is needed. I suspect one issue is that the instruction calls report on what that aircraft is doing at that particular moment, rather than averaging over a few seconds. This means that if your movements are erratic, the calls may be too confusing. Also, the instruction calls do not take into account where your aircraft WILL be. E.g., you can be flying directly on a collision course with the lead at 300 knots, but you might still get a call saying you are too far out because at the moment you were, even though two seconds later you will end up crashing into the lead. You can increase or decrease the frequency of the calls as you like using the F10 menu, but the problem is still there. I might just end up removing them.

UPDATE 2016-05-10, 02:00 +0000

• Fixed relative bearing to lead calculation.
  

UPDATE 2016-05-10, 06:20 +0000

• Improved instructions.
  

UPDATE 2016-05-13 05:30 +0000

• Change reference bearing to lead's right/left, such that line abreast left = 0 degrees; trail left = 45 degrees; astern = 90 degrees etc.
  
• Instead of +/- 15 degree intervals, specify formation position by selecting from one of five slots: line abreast left; trail left; astern; trail right; line abreast right.
  

formation_flight_A-10C_2-ship.miz

Cool. I'll try it out tonight.

Oh I'm definitely going to be trying this out!! Thanks a lot for making this!

So I have tweaked the instructions. And corrected a bug in when reporting the bearing of lead relative to you.

Right now the language of the notifications is pretty informal. May change to using more formal or brevity calls later.

Also note that I found (and continue to find) this reference pretty useful:

[ame=http://www.flyfast.org/sites/all/docs/FAST_FKG.pdf]The Formation Pilot's Knowledge Guide[/ame]

One issue that I note is that bearings from the lead are typically given in angles off the right wing (i.e., such that line abreast is 0 degrees), whereas in the mission/script the angle is with 0 degrees being the lead's heading (such that line abreast is 90 degrees). Will change this in future versions.

Sounds interesting, I will also try it tonight, thankyou:thumbup:

Whoa.......certainly makes you appreciate a 2-dimensional world :) Damn, this is harder than I thought. Let me first say that I'm new to this formation stuff; still in the 'me against the world' single player mode. Have yet successfully 'hooked up' with a Tanker but see this as an incredible opportunity to finally get there.

However, I've got several issues, comments or suggestions right off the bat. Keep in mind I'm flying the A-10C, not a Cessena or fighter.

When it starts out...

1)The 'Lead' is flying at about 170kts with brakes extended which makes it pretty difficult to maintain flight stability from the beginning. To stay in any semblance of a formation I needed flaps which even made it harder....for me. I tried editing the mission file to have Lead flying at 240 kts but that didn't work...not sure what I was really doing ...or did wrong. If you can tell me how to get the Lead up to a reasonable cruising speed I would love to try again.

2) When I finally (temporarily) got into 'slot' and was told to stay there, I didn't have a good view of the Lead from a comfortable position in the cockpit...it was block by the canopy frame. As I tried to locate him the TrackIR put my vision and position all over the cockpit; I might need to dial that in a little before I throw up :cry:

Perhaps a screenshot of the ideal 'slot' position would help the novice get a better idea of where he/she is supposed to be.

All in all, I find this exercise to be very valuable and worth a ride around track many times because it would prove effective in maintaining various aspect of stable flight control in the 3 dimensional world. If I can get into and hold that 'slot' position I could get closer to mastering the refueling task.

Finally...your reference material was not completely loading; not sure what was wrong there but I would like to review all that.

Please advise on how to get the 'Lead up to speed' and thanks very much for this contribution :thumbup::thumbup:

1)The 'Lead' is flying at about 170kts with brakes extended which makes it pretty difficult to maintain flight stability from the beginning. To stay in any semblance of a formation I needed flaps which even made it harder....for me. I tried editing the mission file to have Lead flying at 240 kts but that didn't work...not sure what I was really doing ...or did wrong. If you can tell me how to get the Lead up to a reasonable cruising speed I would love to try again.

 

2) When I finally (temporarily) got into 'slot' and was told to stay there, I didn't have a good view of the Lead from a comfortable position in the cockpit...it was block by the canopy frame.

Thanks for your feedback.

And yes, both of these are absolutely spot-on: I've been frustrated by them, too.

The focus of development, so far, has been to get the script correct: i.e., the instruction calls, the scoring, the radio commands to locate the lead and provide a full breakdown of the formation status (current bearing/range/altitude; desired bearing/range/altitude), as well as ways to adjust the various mission settings dynamically.

The issues you describe have to do with the AI flight itself, something which I've not given much attention to, but definitely need to be addressed:

(1) Getting the lead to fly properly. With their SFM, they can get away with a lot that you cannot, and they have unrealistic transitions (speed/altitude changes seem to take place far more quickly/suddenly than can be followed). I've tried to keep the AI lead steady and level at the same speed. I still find that I often end up either trailing very far behind and then even at max speed find it difficult to catch up, or as in the situation you describe, I end up overshooting. I have found that in some cases the problem is my altitude control: in the last few moments as I am closing in, I am gaining or losing speed by dumping altitude or climbing inadvertently.

I will be working on the AI flight regime next. I actually do not think it is that wrong for most of the flight regime, in the sense that it is sticking to the designated speed and altitude, regardless of HOW it does it (flaps or not). And knowing both of those helps you stick to it (e.g., if you know the AI is at 240 knots, then you know what speed you need to be catch up, keep the current relative position, or fall back).

(2) Yes, the damned canopy frame blocks a critical portion of the sky for the offset formation when the lead is relatively far enough. There is no way around this that I can see. When you get close enough, of course, the lead fills enough of the sky so the canopy frame is not an issue. But it is difficult getting that close early!

I've switched out the A-10C for something like the M2000 and the F-15C (and upped the baseline airspeed suitable). I found formation flying with these much easier for two reasons: (1) visibility is sooooooo much better, as the critical part of the sky is not blocked by the canopy rail; (2) there is so much more power available, which allows for comfortable flying across a greater range of airspeeds (e.g., 300-450 knots). With a baseline airspeed of, e.g, 350-400 knots, you then have a lot of room to catch up quickly or slow down quickly. In contrast, with the A-10, you have just a few knots to play with on either side before you you are too slow for proper authority or are at max level speed.

I'm thinking a better mission to start with might be to fly trail/astern. Then the training is just to control speed and maintain the exact separation, as keeping the correct bearing is a lot easier when you just have to sit behind someone. It seems getting control of speed down is key to maintaining a more complex formation position.

Finally...your reference material was not completely loading; not sure what was wrong there but I would like to review all that.

 

Please advise on how to get the 'Lead up to speed'

Couple of things I failed to address previously.

(1) with the reference material, I just provided a link. I do not know how to get the forum to show the link and not try to load the document in-situ. I think because the document is so big, it is not loading in the preview. But really, all we need is for the link to show. If you google "formation pilot's knowledge guide" you get a number of links to the document.

(2) Unless there was in error in the upload, in the mission I've created the lead should be doing 220 knots?

@ Bearfoot...did you ever get this sorted out so Lead flies at a more reasonable airspeed?

+/- 170 kts is just too hard to stick with; too unstable.

Please advise