Dogfight

What Is Dogfight?

Dogfight is a two-dimensional energy fight between two identical aircraft. You and your opponent carry the same engine, the same wing, the same guns and the same hundred points of hull, so nothing about the fight is decided by what you are sitting in. It is decided entirely by what you do with the energy you start with.

A round opens on a merge: two aeroplanes seven hundred and eighty metres apart, closing head-on, neither with an advantage. That distance is about twelve seconds of flying, which is long enough to see the other aircraft coming and short enough that you have to decide something before you get there. What you decide in those twelve seconds usually settles the next two minutes.

Runs do not end on a timer. They end when your hull reaches zero, or when you fly into the ground because you spent your last height on a turn you did not need. Each opponent you shoot down is replaced by a fresh one, spawned behind you and above you, so the fight does not get easier as it goes on. It gets harder, because you are carrying less energy into each new engagement than you carried into the last one.

How to Play

1. Press Scramble. You start on the merge with the enemy ahead of you and slightly off your nose. Nothing is shooting yet. Look at the SPD readout, which settles at 31 with the nose held level. That is the speed the wing carries your weight at this attitude.
2. Fly at the enemy. Do not turn yet. The single most common way to lose this game is to yank the nose around in the first five seconds, arrive at the merge slow, and spend the rest of the fight watching a faster aeroplane stay behind you.
3. Aim with the nose, not with the flight path. Your guns are bolted to the airframe and they fire along the direction the nose is pointing. At cruising attitude the nose sits about 5.8° above the direction you are actually travelling, and at three hundred metres that gap is thirty-six metres, which is the difference between a hit and a miss over the top of the target. Put the gunsight on the target and the target is what you hit.
4. Fire in short bursts. The gun puts out three points of damage every 0.16 seconds and the target has a hundred points of hull, so a kill takes a little over five seconds of unbroken, correctly aimed fire. That is a long time. You will not get it in one pass, and trying to hold the trigger through a turn will empty your energy long before it empties their hull.
5. Watch the SPD readout more than the enemy. When it drops under about 22 you are in trouble: the enemy reads your speed too, and a slow aeroplane cannot turn, cannot climb, and cannot run. If you see the number falling and you are not about to get a shot, push the nose down and buy the speed back before you need it.
6. Break off when the geometry goes bad. If you are within a couple of hundred metres of the enemy and your nose is more than about fifteen degrees off where they are going, you are not going to solve it by pulling harder. You will fly a big circle in front of their guns. Push the nose down, extend away, and come back with the energy to do it properly.
7. Take the fight upstairs when you have the advantage, and downstairs when you do not. Height is stored speed. An aeroplane with a thousand metres under it can trade that height for the speed to catch anything; an aeroplane at three hundred metres has nothing in the bank and no room to make a mistake.
8. The round ends when your hull is gone or you hit the ground. Your score is a hundred points per kill plus one point for every second you lasted, so surviving is worth something and killing is worth a great deal more. Your best is saved in the browser.

Tips for Winning an Energy Fight

• Climb before the merge, not during it. A few hundred metres of altitude gained on the way in costs you a little speed and buys you the option to dive out of trouble later. Height you did not take is height you cannot spend.
• Never turn more than you have to. A hard turn at cruising speed roughly doubles the total drag on the aeroplane, and drag is speed, and speed is the thing you are actually fighting over. If a small correction gets the nose where it needs to be, make the small correction.
• Let the enemy overshoot. The AI will pull hard to stay with you when it is close and fast, and pulling hard at close range is how aeroplanes end up in front of the one they were chasing. A tight turn at the right moment makes them fly past you, and a fight that was behind you is suddenly in front of you.
• When you are out of energy, dive. This is counterintuitive and it is the heart of the whole game. If you are slow, the answer is not to pull the nose up and try harder, because that makes you slower. Push the nose down, trade the height you have for the speed you need, and re-enter the fight as the faster aeroplane.
• When you are low and slow, pull up. Altitude is the resource that ends the run, so the last few hundred metres of height are worth more than any shot. Pulling up converts speed into height, and height is the only thing between you and the end of the round.
• Do not chase into the vertical unless you started higher. If you follow an enemy into a climb from below, they run out of speed later than you do, and the aeroplane that runs out first is a stationary target at the top of the arc.
• Aim the nose, not the velocity vector. If you find yourself missing consistently, it is almost always this. The guns follow the nose and the nose is above the flight path, so the sight picture that looks like it is shooting over the target is the one that hits.

What Makes Energy Fighting Work

The flight model behind this game is deliberately unforgiving, and it comes down to one relationship that is easy to state and hard to keep in your hands.

The attitude you are holding is not a stick position. It is a trimmed angle of attack, which is the angle between the wing and the air it is moving through. The wing makes lift in proportion to that angle, and the aeroplane settles at whatever speed makes that lift equal its weight. Rearranged, that gives you the speed the aeroplane is going to fly at: V equals the square root of g divided by (CLA times attitude), with CLA being how much lift the wing makes per unit of attitude.

Read that carefully, because it says something no arcade flying game prepares you for: the attitude is in the denominator. Ask for more angle and the aeroplane does not climb away. It settles at a lower speed, and stays there.

At the attitude the aeroplane sits at when the game starts, 0.102, the formula predicts 31 m/s, and if you place the aeroplane exactly there and let go, it holds 31 m/s for as long as you watch it. That is the number on your HUD. It is not a coincidence and it is not a tuning value. It falls out of the geometry.

Which means the honest description of the controls is not "up and down". It is: the nose-up control makes you slower and the nose-down control makes you faster, and the climbing and descending are what happen on the way to those speeds. Pulling the nose up is spending speed to buy height. Pushing it down is spending height to buy speed. There is no third option and no way to get either one for free.

This is why the game has no throttle. A throttle would let you escape the trade. Without one, every decision you make is a decision about which of the two things you would rather have right now, and that is the entire skill of air combat in a single control.

There is a hard edge on it, too. The wing stops flying above an attitude of 0.35, the stall angle, and the pitch control deliberately travels past it, up to 0.42, so you can stall the aeroplane if you insist. Stalling does not flip you upside down or cut the engine. What it does is multiply the drag by about six and a half, and at cruising speed that is enough to take you from 31 m/s to below the 16.7 m/s stall speed in about four-tenths of a second. It is the most effective brake in the game and it is attached to the control you will want to grab when you are frightened.

Why pulling harder makes you slower

There is a second cost to turning, on top of the trade between height and speed, and it is the one that decides fights. Lift is made by pushing air downwards, and the same push that holds the aeroplane up also drags backwards on it. That drag rises with the square of the lift, which means a turn at twice the load factor costs four times the induced drag. Fly straight and the wing is making exactly one g. Pull hard and it is making three, and paying nine times the price for it.

That is why the aeroplane that is turning hardest is the aeroplane losing the fight. Every second spent with the nose hauled back is a second of speed you will not have when the geometry finally comes right. The good pilots in this game look lazy. They are not being lazy, they are staying fast.

The compensating fact, and it is the reason this is a game rather than a punishment, is that a faster aeroplane can pull harder before it stalls. At the 31 m/s cruising speed the wing can be asked for 3.4 g before the angle of attack reaches the stall. At 40 m/s it can be asked for nearly six. Speed is not just the ability to run away. It is the ability to turn, and it is the only thing that is.

Why your nose is not where you are going

A trimmed aeroplane does not point where it is going. It points above where it is going, by exactly the angle of attack the wing needs to hold it up. At the attitude the fight opens at, that angle is 0.102 radians, which is 5.8°. The gunsight is on the nose, and the aeroplane is travelling along a line 5.8° below it.

The guns are bolted to the airframe and bore-sighted along the nose, because that is how guns are fitted to aeroplanes. So the bullets leave along a line 5.8° above your flight path, and over three hundred metres of range that costs you thirty-six metres of height. Thirty-six metres is the difference between a hit and a clean miss over the top of the target, on every shot, for the entire fight.

This is not a decoration in the model. It is the exact bug the enemy AI had when it was first written. It aimed its velocity vector at the target, which is the intuitive thing to do and the wrong thing to do, and its bursts sailed over the player's head at anything past knife range. Fixing it meant aiming the nose instead, and that change took the AI from harmless to dangerous without altering a single bullet.

So when you are lining up a shot: put the gunsight on the target, not on the bit of sky the target is going to fly through. Use the sight. That is what it is for, and the game is built so that trusting it is a real, learnable advantage rather than a cosmetic one.

Reading the merge

The fight opens head-on at 780 metres with both aeroplanes at 31 m/s, closing at about sixty-two metres a second. You have roughly twelve seconds. What you do with them is the most consequential decision in the round, because everything after it is a consequence.

The obvious move is to turn hard towards the enemy immediately and try to get behind them. It is also the losing move. A hard turn at the merge costs you most of your speed, and the enemy arrives at the crossing point still fast, still with all their energy intact, and now able to turn inside you. You have traded your only advantage for nothing.

The better opening is to fly through the merge mostly straight and slightly climbing, accepting that the first pass will not produce a shot, and using the twelve seconds to arrive on the other side with more height than you started with and barely less speed. Nothing has happened yet. That is the point. An energy fight is won by the pilot who is still able to make a hard turn three minutes from now, and the only way to be that pilot is to not make one in the first thirty seconds.

Watch the enemy's nose, not their position. Where an aeroplane is pointing tells you where it is spending energy, and an aeroplane with its nose hauled back is an aeroplane that is about to be slow. The moment you see the enemy turn hard is the moment you have been handed the advantage, whether or not it looks like it.

A Two-Minute Fight on Any Device

A round here lasts somewhere between ninety seconds and three minutes, and that is a deliberate length for a game with no pause between engagements. It is short enough to finish in one sitting and long enough that a fight has phases: the merge, the first engagement, the part where somebody runs out of energy, and the part where that gets punished.

On a desktop or laptop the arrow keys and W and S pitch the aeroplane, Space fires, and P pauses. W and S are bound as well as the arrows because the hand that is not on the space bar tends to be over on that side of the keyboard, and having both sets means you never have to think about which one you are using.

On a phone or a tablet the whole screen becomes the control. Hold the top half to raise the nose and the bottom half to lower it, and use the fire button that sits under your thumb. Holding rather than tapping is deliberate: the pitch control is a rate, so the longer you hold it the further the nose travels, and tapping it repeatedly does not do the same thing. The full pitch range takes 1.2 seconds to sweep, which is slow enough that a held thumb is as precise as a held key.

The canvas resizes to whatever you give it, so the picture fills the screen at any size and in either orientation. There is no aiming cursor to lose track of, because the game reads held inputs rather than pointer position, which means it behaves identically on a mechanical keyboard and on a touchscreen.