The Teledyne Electronic Safety Products (TESP) Navy Aircrew Common Ejection Seat (NACES) sequencer was designed and developed specifically for the Martin-Baker ejection seat to provide a significantly improved recovery envelope through accurate mode selection and precise timing of events. It is fully supported by an O/I level tester (TTU-515/E) that permits full functional verification testing while the sequencer remains mounted on the ejection seat.
The TESP NACES Sequencer features the capability to process data from multiple sources such as on board sensors or external inputs. Programmable logic generates the decisions to fire redundant MIL-STD-1512 initiators according to the algorithm that is required. The original NACES unit is fully qualified and has completed a 6000-hour reliability development test. Production deliveries commenced in August 1989 to support U.S. Navy Aircrew Common Ejection Seats (NACES) in F-14D, F-18 and T-45 aircraft.
The TESP NACES sequencer recently completed a major upgrade of capabilities to provide a safer recovery for a wider range of crewmember sizes. These upgrades include an expanded environmental sensing capability utilizing 21 sensors, extensive event recording during an ejection, continuous environmental sensing and dynamic mode. This Future Advanced Sequencer Technology (FAST) sequencer utilizes modern surface mount components enabling significantly improved performance and capabilities. This new NACES/FAST sequencer incorporates advanced processors with over 12 megabytes of program memory and 6 megabytes of event recorder memory and retains all the fail-op/fail-safe features of the original NACES design. This highly upgraded unit completed a Highly Accelerated Life Test (HALT), a qualification program, and a series of sled and flight tests. It is scheduled to begin production deliveries in early 2002. The NACES/FAST sequencer is fully supported by the existing O/I level tester (TTU-515/E).
Although the unit was designed and is in production for the U.S. Navy Aircrew Common Ejection Seat (NACES) the electronics are capable of
reading other types of sensors and implementing different logic in software. The fundamental architecture, high reliability and processing power make it an ideal platform for other controller or sequencer applications.