GPS
Di Vosh, during the last 2 years of my flying career I carried a hand held portable GPS unit with me on all my flights, just in case. This was in response to the 757 crash out of the Puerto Plata DR one night due to loss of airspeed indication. Also the the crash out of Lima Peru with taped over static ports.
The GPS provided me with ground speed, course and true altitude (not pressure alt). That is all the pilot of a jet needs to stay alive when all hell breaks loose.
My advice to all pilots is, get and carry a hand held GPS unit and take it with you on all your flights. And use it, just in case. Also please do not fly into CB's, they can give you a headache.