Can an air elemental carrying a druid provide a better fly effect than the Fly spell?

Question

Can a summoned air elemental fly while carrying a spellcaster, in effect providing a short term copy of the Fly spell?

A Halfling male druid has a base weight of 30 pounds, and a modifier of (2d4 x 1) additional pounds. So max weight is 38 pounds.

A Small Air Elemental has a strength score of 12. This means a Light load is 43 pounds or less, and a Medium load is 44 to 86 pounds. Max load for Strength 12 is 130 pounds.

Suppose I have a Halfling male druid weighing 43 pounds total which includes a minimal set of gear. He casts Summon Nature's Ally II and conjures a Small Air Elemental with a Fly speed of 100. He instructs the air elemental to carry him.

Can the Druid fly in this manner until the duration of Summon Nature's Ally II expires (minimum three rounds)?

Can he cast spells while being carried, just like the Fly spell permits?

Am I missing something which prohibits this use of this spell in this manner?

Note: I am asking if this is possible. I am not asking if it is a good use of resources.

Answer 1

Yes, but it ventures into rules-unspecified territory

Since the Air Elemental can lift the Halfling's weight, the Air Elemental can carry the Halfling. One example part of the encumberance rules that permit this are the lifting/dragging rules, which state "A character can lift as much as his maximum load over his head". A Halfling cannot, however, mount a Small Air Elemental, because such a creature is the same size as it (i.e. not at least one size larger). When carried, rather than mounted, the rules have nothing in particular to say about e.g. your ability to cast spells or otherwise take actions-- the rules do not expect creatures to be carried (outside of effects like the Air Elemental's Whirlwind, which specify how they work).