Triggers: Be unqualified for any other ending.

Ending #1 is the most demanding as it requires you to avoid every other ending. You'll have to route out your actions carefully for each stage to ensure that you avoid falling into any of these categories.

Below is my suggested route:

Stage 1:

Attack the seagulls.

Shoot down Blue Crow quickly.

Shoot down Tequila after shooting down Big Magnum.

Stage 2

Shoot down Fernet's blimp or blow up Fernet's blimp, but miss one of the blimps in her fleet.
(Letting one drop after shooting out the balloon counts as a miss.)

Shoot down Blue Crow after listening to him.

Shoot out the head of Avion in his first phase.

Don't destroy Avion's rear wing in his second phase.

Stage 3 (Merchant)

Time out on one of Merchant's segments.

Stage 3 (Lone Rider)

Time out on the first bonus chance.

Shoot out Lone Rider's wheels on his final phase.

Stage 4

Shoot out Rose Windmill's body on her 2nd fight.

Stage 5

Ignore Green Frog's back engines.

Finish Golden Falcon by destroying the body. (If 1cc.)

Trigger: Shoot down Blue Crow before Peat can finish talking in Stage 1 & Stage 2

Peat talks slowly in Stage 1, so shooting him before he finishes is simple.
However Peat talks quickly in Stage 2, so just remember that he appears immediately after the two big turrets near the end of the first bonus chance.

Trigger: Shoot down Blue Crow after listening to Peat in Stage 1 & Stage 2 and see him in Stage 5.

It's much like Ending 2 but you wait a second before shooting down Blue Crow. Then play through the rest of the game normally.

Note: Blue Crow in stage 5 has priority over Fernet, but not Pirates or White Cross. This means that to get this ending you will have to either destroy Mescal before the pirate goons during her fight or destroy Big Magnum and shoot down Tequila to eliminate any chance of a pirate ending.

Trigger: Skip Mescal then Spare Tequila.

You can skip Mescal by either having a low score, sparing the seagulls and letting Peat finish talking before shooting him down, or by sparing Blue Crow. I recommend sparing Blue Crow as it will lose you the least amount of points out of the three.

Trigger: Destroy Mescal after the pirate goons in her fight, then shoot down Tequila without destroying Big Magnum, then see the pirates in Stage 5.

As long as you don't trigger White Cross to appear in Stage 5, you should get this ending.

Trigger: Shoot down Mescal before the pirates in her fight, shoot out the wing flaps instead of the pirates in Tequila's 3rd Phase, then shoot down Tequila without destroying Big Magnum.

You should get dialogue with the pirates coming back with an extra line saying something along the lines of "We'll never forget you, Captain."

Trigger: Blow up Fernet's blimp and blow up her entire fleet and see her in Stage 5.

This is one of the tougher endings to get, as the blimps can easily fall past you after the balloons are destroyed. This counts as a miss, so aim carefully.

If you blow up all the blimps during the 2nd wave, the butler should say something along the lines of "Sorry milady," rather than criticize you.

Fernet has the lowest priority of any ally for Stage 5. Don't listen to Blue Crow twice, destroy Tequila's Big Magnum, and don't trigger White Cross for Stage 5.

Trigger: Spare Fernet.

This is one of the easiest endings to get, just let Fernet, the golden blimp, pass and then play the rest of the game normally.

Trigger: Shoot down Avion after seeing his final phase with many heads.

To trigger this final phase of Avion, don't shoot out the head in the 1st phase. Aim for the engines. Then on Avion's 3rd phase, time out or shoot out the wings.

Trigger: Shoot down Avion without destroying the body of the aircraft.

In order to do this you need to shoot the middle of Avion during his 2nd phase. It doesn't hit his body, but hits his rear wing instead. Afterwards aim for the wing flaps rather than the body of Avion on his 3rd phase.

Trigger: Complete every bonus chance on Lone Rider's route and then shoot out Lone Rider's wheels on the final phase of his fight.

The first one can be a bit tricky, as it is tough to get a chain at the start, but aiming for the center of the punk's cars will help destroy them faster.

Trigger: Blow up Lone Rider.

On the final phase of Lone Rider's fight, simply aim for the center of his car.

Trigger: Blow up all segments of Merchant's train.

Be quick during Merchant's fight, as you can time out if you're too slow.

Trigger: Take less than 2 hits before meeting up with White Cross, Spare Lone Rider, Spare Rose Windmill, then see White Cross in Stage 5.

You can spare Lone Rider by flying low on the screen behind him on his final phase. Lone Rider will slowly move upwards as he gains speed, let this happen long enough and he escapes.

You can also spare Rose Windmill on her 3rd fight. Simply don't shoot her and her plane fails.

Doing this will trigger White Cross in Stage 5, who takes priority over any other ally.

Trigger: Shoot down Rose Windmill in her 3rd fight.

During Rose Windmill's 2nd fight, aim for her wings. Once both wings are destroyed she will retreat and come back a 3rd time.

Trigger: Spare Gray Whale

In order to spare Gray Whale, you have to spare Rose Windmill. This unlocks a phase where you are able to shoot out two extra exhaust pipes. Do this and then destroy the rest of the engines to spare Gray Whale.

Trigger: Receive good rankings from Grain and then destroy Green Frog's back engines in his final phase.

Grain's dialogue after his fight depends on how you are ranked in previous stages. Try aiming for at least 3 stars for each stage. If you take out the back engines with good rankings, Grain should say something along the lines of "You and Red Barrel make a great team."

Trigger: Defeat Flying Castle without using continues, Shoot out the exhaust pipes of Golden Falcon before destroying the wing flaps on phase 3, then finish Golden Falcon by shooting out the wings on his final phase.

This ending is pretty tough since you can't use any continues before Golden Falcon.

Be careful, and good luck.