TD has various meanings in the NASA category. Discover the full forms, definitions, and usage contexts of TD in NASA.
A relay having an intentional delaying device. The controlled period between the functioning of two events. A period of time when a load is energized or de-energized. At the end of the desired time period the load changes state (i.e. on or off). Time delay a time-current response char-acteristic, established by national standards, which means that a time-delay fuse is de-signed to carry five times rated current for 10 seconds before opening. also envelope delay.
NASASynonym of landing. May also refer to a stopover that does not involve a change of aircraft or flight.
NASATo make controlled contact with the landing surface after a flight \nExample: If the atmospheric pressure at an airfield is 1,000 millibars (mb) and that pressure is set on the sub-scale of an aircraft altimeter, when the aircraft touches down at the airfield, the altimeter will read zero.
NASALast updated: