11 research outputs found
Data Analysis of Phoenix Reusable Launch Vehicle Demonstrator Flight Test
The Phoenix vehicle was designed to flight demonstrate the automatic and unpowered horizontal landing of a representative, winged reusable launch vehicle. The shape of the test vehicle was derived from the suborbital reusable launch vehicle concept Hopper. Three automatic landing tests were completed successfully in May 2004. Methods of system identification were applied to the flight data to evaluate the performance and to improve the design models and databases for future applications. A specific emphasis was placed on the evaluation of the onboard navigation system, air data sensor, aerodynamic model, landing gear effects and ground-roll characteristics. This paper gives a brief overview of the Phoenix mission and elaborates on the flight data analysis and of the preceding wind tunnel campaigns, to allow a comparison of results from different approaches
True’s beaked whale (<i>Mesoplodon mirus</i>) in Macaronesia
The True’s beaked whale (Mesoplodon mirus, True 1913) is a poorly known member of the Ziphiidae family. Its distribution in the northern hemisphere is thought to be restricted to the temperate or warm temperate waters of the North Atlantic, while a few stranding records from the southern hemisphere suggest a wider and antitropical distribution, extending to waters from the Atlantic coast of Brazil to South Africa, Mozambique, Australia and the Tasman Sea coast of New Zealand. This paper (i) reports the first molecular confirmation of the occurrence of the True’s beaked whale at the southern limit of its distribution recorded in the northeast Atlantic: the Azores and Canary Islands (macaronesian ecoregion); (ii) describes a new colouration for this species using evidence from a whale with molecular species confirmation; and (iii) contributes to the sparse worldwide database of live sightings, including the first underwater video recording of this species and close images of a calf. Species identification was confirmed in two cases using mitochondrial DNA control region and cytochrome b gene markers: a subadult male True’s beaked whale that stranded in El Hierro, Canary Islands, in November 2012, and a subadult male found floating dead near Faial, the Azores, in July 2004. The whale that stranded in the Canary Islands had a clearly delimited white area on its head, extending posteriorly from the tip of the beak to cover the blowhole dorsally and the gular grooves ventrally. This colouration contrasts with previous descriptions for the species and it may be rare, but it exemplifies the variability of the colouration of True’s beaked whales in the North Atlantic, further confirmed here by live sightings data. The recording of several observations of this species in deep but relatively coastal waters off the Azores and the Canary Islands suggests that these archipelagos may be unique locations to study the behaviour of the enigmatic True’s beaked whale