Apollo Command Module Block II Earth Landing Sequence Controller, measuring 7.75 x 4.5 x 3, bearing a large parts tag affixed to the top, reading: “Item Name: Sequence Controller, NAA Control No. ME 901-0001-0038, Contract No. NAS 9-150, NAA Inspection Serial No. 09390AAF0222, Manufacturer: Northrop Ventura, Mfr Serial No. 37, Mfr Part No. R8204-501.” Underside bears an affixed Radioplane inspection label and hexagonal plate engraved "Current Equalizing Module." The unit has four connector ports labeled “J1” through “J4,” and a blue “Static Air” port. In fine condition. Part of the Apollo Command Module's sequential events control system, the controller was employed during spacecraft reentry to sense barometric pressure, and automatically trigger firing pyrotechnics that released the Apex cover, drogue, pilot and main parachutes prior to splashdown.
Terms and abbreviations used in our descriptions.