With similar weapons why does an AH64 Apache require a pilot and gunner when the A10 Warthog only needs a pilot? The Apache has a 30mm chain gun. It carries Hellfire (anti armor), Stinger/Sidewinder (air to air) and Hydra (air to ground, APKWS guidance package available) missiles. 


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The Warthog has a 30mm gatling gun. It carries Maverick (30cm air to ground including armor), Hydra (70mm air to ground) and Sidewinder missiles, plus a variety of bombs. 


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The Warthog seems to have a more capable and complex weapons load, so why doesn't it use a separate gunner like the Apache?



From comments:

The ULB (Unmanned Little Bird) version of the AH6 can fly with two, one, or zero pilots, so it seems that helicopters can be automated like fixed wing aircraft.

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The Kiowa Warrior 50cal machine gun was not turret mounted; it was fixed to the airframe like the A10, though not buried in it. This is used in an armed recon role, not attack.


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Mainly it's because the A10's pilot just has to point his aircraft at the target from a certain height while in forward flight, whereas the helicopter, being able to hover, needs to be able to engage a target while not pointed directly at it, while the pilot is busy flying a machine that takes a lot more attention than a fixed wing aircraft.  

Especially when considering the Apache's original tactical function, which was to hover below the tree tops, pop up and engage a Soviet tank, and drop out of sight again.  As the pilot you wouldn't want to be managing the weapon systems AND flying the machine and avoiding obstacles.