In this paper we analyze a large scale delay tolerant network (DTN) of transoceanic aircraft. We assume that each airplane in our network is equipped with a simple communication system based on IEEE802.11b/g, with a communication link of around 20 km. The characterization of this large aeronautical DTN will be used to choose routing strategies for passenger or company data, only through the contacts between airplanes, in order to use this network as a cheaper alternative to other communications systems, or as backup when no other communication systems are available. Instead of relying on synthetic data, we carry our analysis from the actual traces of 2,550 trans-Atlantic flights in the ns-3 simulator, to provide a detailed study of the network connectivity and mobility metrics (node degree, clustering, any contact time and inter any contact time). The impact of other parameters (such as radio coverage) on the network is also analyzed.