Immelmann / Split-S in space

Hi guys,
hello Andrea,

during a friendly game with a friend, who like me is new to BSG, we discussed some ways to move your spaceship that seem "missing" in the rules.

-> a way to change "height" (I know their is no such thing in space !) and direction, like an "Immelmann" to gain a level of "height" or a "Split-S" to reduce one level.

So we came to the following way to achieve this:

1) for "Immelmann"
- usage of a special card ( "blank card" with extra marking "Immelmann/Split S") AND a regular straight movement card
- settings of the control panel slider: Altitude +1 / still uses the "Back" setting of the control panel
- use the backward option on a straight movement card, BUT put the card in front of the model, then turn the model 180 degrees, so it faces the direction it came from.

2) for "Split-S"
- usage of a special card ( "blank card" with extra marking "Immelmann/Split S") AND a regular straight movement card
- setting of the control panel slider: Altitude -1 / still uses the "Back" setting of the control panel
- use the backward option on a straight movement card, BUT put the card in front of the model, then turn the model 180 degrees, so it faces the direction it came from.

Movements still count as a "Straight" maneuver, but also as "Difficult" / "Kinetic energy 3" and as a 3G-maneuver !

What do you think of this ? Does it make sense ?

So, you want to duplicate a maneuver used in atmosphere, but in space?

I haven't used Altitude in BSG, but I'd have to say that an 'Immelmann' or 'Split-S' maneuver wouldn't be possible.

To change level, a ship has to thrust in the desired direction. So, thrust in the direction that gets you to the new level, and then Rotate, and change direction. No need for any new cards or rules?

Am I missing something?

Should be possible to do in BGS such a maneuver in 2 turns instead of 3 like WGS or WGF, but need to check the rules first with altitude.

The Kinetik Energy of a straight maneuver is needed to have something in the middle between a reverse (-1) and an overboost (6).

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Originally Posted by OldGuy59

So, you want to duplicate a maneuver used in atmosphere, but in space?

I haven't used Altitude in BSG, but I'd have to say that an 'Immelmann' or 'Split-S' maneuver wouldn't be possible.

To change level, a ship has to thrust in the desired direction. So, thrust in the direction that gets you to the new level, and then Rotate, and change direction. No need for any new cards or rules?

Am I missing something?

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In my opinion it is just a verctor calculation.
In atmospheric flight the control surfaces give the a/c the change of direction and altitude. In modern fighter jets also the thrust vector control or thrust vectoring.
In space flight the directional thrusters do the exact same.

I'm looking at an Immelmann maneuver as thrust against atmosphere. There is no atmosphere to work against in space. But, as you say, vectors apply.

However, for space, the main vector comes from the main engine. The directional thrusters don't have enough energy to cause a level change. The main engine has to point in a direction to effect the change of level and direction desired. Somewhere in this, the firing arc will be pointed off in a useless direction.

So, attempting the Immelmann in a single card may not give you any advantage that a two card maneuver (all ready in the deck) can provide. Wings of Glory takes three cards now, so we're already ahead with BSG.

I'm gonna have to sit down and draw pictures to get my head around the vectors involved, so I can see how this should actually work. Then, look at the cards available.

PS: Oh. And to change direction by 180 degrees in space, you have to change your vector to zero in the original direction, and build it back up to the desired acceleration in the new. I don't see maintaining an acceleration rating throughout as is, sort of, what hsppens in an Immelmann/Split-S ( yes, there is a speed change in both, but not to zero).

"The directional thrusters don't have enough energy to cause a level change"

They don't have to, as they are not responsible for the altitude change.
A directional thruster in the lower nose will push the nose up, an additional thruster in the upper tail will push the tail down, so ever increasing the speed of change of attitude.
As long as the attitude of the nose is less than 45°up the spaceship still moves forward, but to a lesser extent.
nose up 0° = 100% forward movement / no upward movement,
nose up 22,5° = 25% forward movement / 75% upward movement,
nose up 90° = no forward movement / 100% upward movement

Or of course the other way around.
A directional thruster in the upper nose will push the nose down, an additional thruster in the lower tail will push the tail up.

The actual "altitude" change still comes from the main thrust.


The initial reason of an inclusion of this "Immelmann/Split-S"-style maneuver is not an altitude change per se, but a quick directional change of 180° as well !!


"So, attempting the Immelmann in a single card may not give you any advantage that a two card maneuver (all ready in the deck) can provide."
Maybe I am ignorant, but which actual manouver (which cards in which sequence) do you mean ?

As I don't play the 3D option, I may be the one confused. I will dig out the game and walk through the process to ensure I have the level change process down. Then, see if the direction change can be overlapped on to it. The level change is supposed to be a straight, so doing a Rotation could be possible. Then, followed by a Change Direction card and a maneuver in the new direction.

The only thing that mucks up this is that any 180 degree change of vector in space requires that a ship reduce to 0 acceleration somewhere.

I've been thinking about these maneuvers myself, in the context of a vertical half-loop around the spherical planetoid. A one-level altitude change might be a little easier than that.

Vertical motion/changing altitude is different from the other movement in this game in that it is simultaneous with horizontal movement, but it kind of has to be. I think that the key thing to remember here is that changing altitude is a maneuver itself with a Kinetic Energy (KE) of 3, but it does not require a card. Stopping and changing altitude is a legal move for raiders with any KE and for vipers with any KE from 0 to 6. Following any maneuver, an "Immelman" or "Split-S" can be done in two turns:

Turn 1) Pick any maneuver card because you are going to stop. Set your control panel to (a) an altitude of +1/-1, (b) stopped velocity, (c) kinetic energy of 3, and (4) 180 rotation.
Turn 2) Pick the change direction and straight maneuver cards. Set your control panel to (a) an altitude of 0, (b) velocity of choice, (c) kinetic energy to match, and (4) 0 rotation.

*Note: To perform a turn around the spherical planetoid requires an additional change of altitude on Turn 2, which should still be legal according to the rules with any straight maneuver.
*Note 2: If a visual helps, look at this diagram from Wikimedia Commons. Turn 1 goes from point 1 to point 2 (the vertical climb) in the diagram and Turn 2 goes from point 2 to point 3.

It looks like there is a lot going on in Turn 1, and part of that is because the ship rotation doesn't make sense there in real life. However, the game requires a rotation the turn before a ship changes direction, if I am not mistaken, so it has to be done during Turn 1. Call it the ship doing a barrel roll early. If I misunderstand the altitude change rules or the rotation/change direction rules, please let me know.

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The only thing that mucks up this is that any 180 degree change of vector in space requires that a ship reduce to 0 acceleration somewhere.

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I'm a physics teacher, so please don't take offense at this correction, Mike. A 180 degree change in vector requires velocity to reduce to zero in the initial direction of motion. Acceleration is change in velocity, so it cannot be zero during the turn. During an Immelman, the acceleration on the pilot is always directed toward their head, but their horizontal velocity is zero when the plane is vertical.

A simplified way of looking at maneuvers using altitude.

1.Always play 2 cards.
2. Restrictions - both cards g limits added together may not exceed type's g limit.
3. Set your KE to be previous KE +/- acceleration (cannot accelerate if course /= heading)
4. When being tailed, show your opponent your first card (only) before they plan their move.

Course is the direction of movement. Heading is the direction the model is pointing.

When heading = course, the usual state of affairs.

a. Normal move, KE -1 to 3:
1st card a maneuver card, 2nd card blank, alt = 0, speed = KE. Heading may be changed after 1st card.

b. Overboost maneuver, KE 4 to 6
1st card overboost, 2nd card a maneuver. Heading may be changed after 1st card. Alt = 0. Speed = KE - 3

c. Change alt, KE 3 to 6
1st card blank, alt = + or - 1, 2nd card a maneuver. No change of heading. Speed = KE - 3.

So there are only 3 kinds of maneuvers when course = heading.

When heading /= course

d. Normal, KE -1 to 3
First card a straight maneuver, 2nd card blank. No change to KE. Alt = 0. Direction may be changed after first card. Speed = KE.

e. Overboost, KE 4 to 6
First card a straight overboost. 2nd card a straight maneuver. No change to KE. Alt = 0. Heading may be changed after first card. Speed = KE - 3.

f. Make course = heading
First card a cse=hdg card, (use template to drift, KE -1 to 1 none, KE 2-4 short, KE 5-6 long). 2nd card a maneuver card. Alt = 0. No change to heading, and afterwards both KE and speed = 0 +/- acceleration (see official errata and my own interpretation)

So there are only 3 other kinds of maneuvers when course /= heading.


Any two turns where in the first turn, heading is changed to differ from course, then in the second turn course is changed to heading, is the equivalent of an Immelman. Any three turns where the first changes altitude, the second changes heading to differ from course, and the third makes the course equal to heading, is the equivalent of a split S or half loop.

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Originally Posted by Tobin Dax

I've been thinking about these maneuvers myself, in the context of a vertical half-loop around the spherical planetoid. A one-level altitude change might be a little easier than that.

Vertical motion/changing altitude is different from the other movement in this game in that it is simultaneous with horizontal movement, but it kind of has to be. I think that the key thing to remember here is that changing altitude is a maneuver itself with a Kinetic Energy (KE) of 3, but it does not require a card. Stopping and changing altitude is a legal move for raiders with any KE and for vipers with any KE from 0 to 6. Following any maneuver, an "Immelman" or "Split-S" can be done in two turns:

Turn 1) Pick any maneuver card because you are going to stop. Set your control panel to (a) an altitude of +1/-1, (b) stopped velocity, (c) kinetic energy of 3, and (4) 180 rotation.
Turn 2) Pick the change direction and straight maneuver cards. Set your control panel to (a) an altitude of 0, (b) velocity of choice, (c) kinetic energy to match, and (4) 0 rotation.

*Note: To perform a turn around the spherical planetoid requires an additional change of altitude on Turn 2, which should still be legal according to the rules with any straight maneuver.
*Note 2: If a visual helps, look at this diagram from Wikimedia Commons. Turn 1 goes from point 1 to point 2 (the vertical climb) in the diagram and Turn 2 goes from point 2 to point 3.

It looks like there is a lot going on in Turn 1, and part of that is because the ship rotation doesn't make sense there in real life. However, the game requires a rotation the turn before a ship changes direction, if I am not mistaken, so it has to be done during Turn 1. Call it the ship doing a barrel roll early. If I misunderstand the altitude change rules or the rotation/change direction rules, please let me know.



I'm a physics teacher, so please don't take offense at this correction, Mike. A 180 degree change in vector requires velocity to reduce to zero in the initial direction of motion. Acceleration is change in velocity, so it cannot be zero during the turn. During an Immelman, the acceleration on the pilot is always directed toward their head, but their horizontal velocity is zero when the plane is vertical.

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Trying to describe 3D movement in a 2D game is going to be a problem. And, really, IMHO, both Wings of Glory and BSG are 2D games with an attempt to inject 3D. Also, I was trying to stay with the game mechanics in my descriptions, so I didn't use the term "velocity".

For Immelmann turns, there is also issues in what that means to different individuals. The graphic you linked is not a WWI Immelmann, but what I call a half-loop.
The WWI maneuver is this: Wikipedia.org - WW1 Immelmann
Also, some people confuse the Immelmann with this maneuver: Wikipedia.org - Chandelle

All the above have a change of direction of 180 degrees. Supposedly, all of the above retain some type of energy, although in one vector or another they all have a "0" somewhere. All the above use a fluid (air) to act against to effect the change in direction. Again, not being a scientist, I'm kludging this with what experience I have.

I can't see any of these being used in space. My deficiency, perhaps. And in game terms, if you want to go back over your previous path, even at a different "Altitude", thrust against the original direction has to be applied to bring that movement to '0' (or almost), if thinking of the WWI Immelmann, or even the half-loop. I looked up Orbital Maneuvers, as I can't find anything on-line that decribes "Space Combat Maneuvers". The closest I could find to an Immelmann was this:
Wikipedia.org - Orbital Maneuver: Impulsive Maneuver.
It doesn't feel completely right, to me, but it's close. How to do that with game mechanics? I still have to put models on the table, and play it out.

Here is my issue in all this: The direction the ship faces will not be towards the enemy ship, if your main engines have to apply thrust in a specific direction to get the resultant vector desired. I dont' see them matching up, at least not without physical representation.

In past games, without Level changes, I just Rotate and fire at the enemy. Then, I Change Direction and come at the enemy, maneuvering as required. Two cards, no added special cards. 180 degree change in movement (almost, depending on the following maneuver).

Oh. Wow! Just checked the rules again. You can turn while changing levels. You just can't plan Overboosts (cause you are going to add +3 KE to change levels), you can't Change Direction (cause you need main thrusters to change levels), nor can you use 'backward' maneuvers. But, the maneuver doesn't have to be a straight? This doesn't help my brain. I have vectors going in all directions, now.

I would have thought an immelmann ( if done as a evasive manoeuvre ) could be done flat... up and down manoeuvres could be just be done as you would in WOG .. but a change in direction up or down would mean extra pegs..

The problem for me with movement is that you cannot move in the direction of up or down by flipping 90 degrees. Then how to you move on that axis which would add more movement problems.

Q1: Wouldn't space combat eventually conform to being on 1 plane not multi planes, ie X and Y axis?

My thinking there is that perhaps it would be a subconcious reaction rather than a conscious one.

Q2: In view of the rules not allowing for multi planer combat would a flip over or flip down special maneuver (Imelmann or Split S for want of anything better) be acceptable as proposed in another post?

I like the idea of cards that enhance the play of 3D Space. The ideas presented here are good threads of thought and I believe there is merit in pursuing that possibility although the added complexity would present challenges for less experienced players. Something else to consider would be gimbal options on the space craft and base to allow for the directional changes in vertical and other positioning of the ships in nose up and down positions. Would it be possible to allow for measuring in 3D space for shooting with the arc following the craft somehow instead of the base, mimicking the real 3D aspect? Has this been done on tabletop games before? It might not be too difficult to measure in 3D space versus on the flat table if using altitude style play. I may also be losing my mind too.

The only 2 ways I can think of how to pull the 3d manoeuvring is either using a laboratory stand or some kind of upper grid system above the gaming table, where the ships hang down.

It could be possible to mount a magnetic gimbal ball like I have see done with some wings of glory aircraft.

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Originally Posted by Tristan

The only 2 ways I can think of how to pull the 3d manoeuvring is either using a laboratory stand or some kind of upper grid system above the gaming table, where the ships hang down.

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A telescope antenna would also be an option. Have seen this somewhere in the forum.