Sparrow

The Sparrow is a small helicopter.  It's small and manueverable but does not have a machine gun like the Sea Sparrow.

One spawns on Madd Dogg's Mansion.

More info:
gta.wikia.com/wiki/Sparrow
https://www.grandtheftwiki.com/Sparrow

Sea Sparrow

 

The Seasparrow is a small helicopter equipped with floats.  It's small, maneuverable,  has a machine gun, and it can land anywhere.

One spawns north of the Verdant Meadows airfield, and another is near the dam.

More info:
gta.wikia.com/wiki/Sea_Sparrow
https://www.grandtheftwiki.com/Sea_Sparrow

Raindance

 

The Raindance is an emergency helicopter, presumably used to drop water on wildfires.

More info:

gta.wikia.com/wiki/Raindance 

https://www.grandtheftwiki.com/Raindance 

Police Maverick

The Police Maverick is a Maverick used by the police.  It has a machine gun.

One spawns on the roof of the police station in Los Santos.

More info:
gta.wikia.com/wiki/Police_Maverick
https://www.grandtheftwiki.com/Police_Maverick

News Chopper

 

The News Chopper is a helicopter.  It is a shorter version of the Maverick.  

The easiest way to get one is to steal it from the "Whirly Bird Waypoint" 'race'.

More info:
gta.wikia.com/wiki/News_Chopper
https://www.grandtheftwiki.com/News_Chopper

Maverick

The Maverick is a helicopter.  It's related to the Police Maverick and the News Chopper.

One spawns on the helipad on the north side of the San Fierro police station.

More info:
gta.wikia.com/wiki/Maverick
https://www.grandtheftwiki.com/Maverick

Leviathan

 

The Leviathan is a large, slow helicopter.

One spawns at the Verdant Meadows Airfield, another at the San Fierro airport.

More info:
gta.wikia.com/wiki/Leviathan
https://www.grandtheftwiki.com/Leviathan

Hunter

The Hunter is a military helicopter.  It's very fast and maneuverable, and it has a machine gun and rockets.

One spawns at Verdant Meadows Airfield.

More info:
gta.wikia.com/wiki/Hunter
https://www.grandtheftwiki.com/Hunter

Cargobob

The Cargobob is a large military helicopter.

One spawns northeast of Las Venturas (but you pretty much need a helicopter or jetpack to get to it), and other one spawns in Area 69.

More info:
gta.wikia.com/wiki/Cargobob
https://www.grandtheftwiki.com/Cargobob

Stunt Plane

 

The Stunt plane is a small biplane.   It is very quick to take-off and very maneuverable (but twitchy).  Like the Cropduster you can make smoke trails with it.

One spawns at the Verdant Meadows Airfield.

More info:

gta.wikia.com/wiki/Stuntplane 

https://www.grandtheftwiki.com/Stunt_Plane 

Skimmer

The Skimmer is a Dodo with floats instead of wheels so it can land on water.  It's not really a good idea to land it on the ground as it just sort of slides.

One spawns across the bay from the boat school, and another one spawns north of the dam.

More info:
gta.wikia.com/wiki/Skimmer
https://www.grandtheftwiki.com/Skimmer

Shamal

The Shamal is a fairly small commercial jet.  You can find them at the three commercial airports.

More info:
gta.wikia.com/wiki/Shamal
 https://www.grandtheftwiki.com/Shamal

Rustler

The Rustler is a military plane.  It's equipped with machine guns.  It's sort of slow to take-off.

One spawns at Verdant Meadows Airfield.

More info:
gta.wikia.com/wiki/Rustler
https://www.grandtheftwiki.com/Rustler

Nevada

 

The Nevada is a large commercial plane.  It isn't a good idea to try to stuff it in the hanger.

One spawns at the San Fierro airport.

More info:
gta.wikia.com/wiki/Nevada
 https://www.grandtheftwiki.com/Nevada

Hydra

The Hydra is a military jet.  You can adjust the angle of the jets for vertical takeoffs and landing.  It has missiles.

One spawns at the Verdant Meadows Airfield and another in Area 69.  If you get 100% another will spawn at CJ's house.

More info:
gta.wikia.com/wiki/Hydra
https://www.grandtheftwiki.com/Hydra

Dodo

The Dodo is a small plane.  It's slow and easy to fly.  The Skimmer is based off of the Dodo.

You can find them at the major commercial airports.

More info:
gta.wikia.com/wiki/Dodo
https://www.grandtheftwiki.com/Dodo

Cropduster

The Cropduster is a small biplane used for dusting crops.  One spawns near the Quarry and other on a hill near a farm in Flint Valley.  You can turn the spray on and off.

More info:
gta.wikia.com/wiki/Cropduster
https://www.grandtheftwiki.com/Cropduster

Beagle

 

The Beagle is fairly small commercial plane.  It is slow and easy to fly.

You can find one at the San Fierro airport. 

More info:

gta.wikia.com/wiki/Beagle 

https://www.grandtheftwiki.com/Beagle 

 

AT-400

The AT-400 is a huge commercial plane found in a hanger in the southeast of the Las Venturas airport.

More info:
gta.wikia.com/wiki/AT-400
https://www.grandtheftwiki.com/AT-400

Yosemite

The Yosemite is a large, two door, rear-wheel drive pick-up truck. They are sadly disappointing to drive.

 

More info:

gta.wikia.com/wiki/Yosemite
https://www.grandtheftwiki.com/Yosemite