This paper presents two mechanisms for modeling alliance formation between leader carriers for more efficient utilization of their resources: partial collaboration and complete collaboration. The performance of these alliance formation mechanisms are compared against the no collaboration case for various network topologies and demand levels. In the partial collaboration case, each leader carrier first maximizes his individual objective and leases out the residual capacity to other carriers. In the complete collaboration case all leader carriers join together to maximize the profit of the alliance. The profits are then distributed among the alliance members using shapley value principle. Numerical tests reveal that the topology of the network plays an important role in determining the profit of each collaboration mechanism.