Can I trip with the melee attacks from Whirlwind Attack?

Question

I am in the process of building a character to play in an Iron Heroes game, and I was wondering if it was possible to make a whirlwind attack, and with the melee attack provided by whirlwind attack make a trip special attack.

Is this possible? As the action cost of a Trip Attempt is listed as [Varies], and is initiated with a melee touch attack, should a character be able to perform trip attacks with the melee attacks generated by Whirlwind Attack?

RAW - Whirlwind attack's usage is as follows; on a full attack action, giving up your normal attacks and instead make a single melee attack at full BAB against each opponent within reach.
My question lies in the interpretation of whether or not a trip attempt may be used as a single melee attack. Due to the only action requirement listed for a trip attempt is the melee touch attack required to initiate the trip.

Answer 1

Yes. When the IH rules say that you may do something 'as an attack', they always mean that you can replace the given type of attack with the special action, unless the attack is being granted by an attack of opportunity.

This is unfortunately not stated explicitly, but we can infer it fairly naturally from the special-case wording describing attacks of opportunity:

You cannot use special attack types, such as trips or disarms, as those require more time and focus than you normally have when making an attack of opportunity. (Iron Heroes, p. 181, 'Making Attacks of Opportunity')

This means that you can whirlwind trip with a halberd. Unfortunately, per Whirlwind Attack, you can't then follow up with the extra attack granted by Improved Trip 4. At least until you get Whirlwind Attack 10.