Hi, http://ntrs.nasa.gov/search.jsp?R=659637&id=1&qs=Ntt%3Dburnelli%252Bairplane%26Ntk%3Dall%26Ntx%3Dmode%2520matchall%26N%3D0%26Ns%3DHarvestDate%257c1 http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19930092656_1993092656.pdf