Projects / Completed
A2146 — Manufacturability of Output Traveling Wave Tubes for Jammer Applications Phase 2
PERIOD OF PERFORMANCE: June 2006 to June 2007
The EA-6B Prowler Band 4 Transmitter conducts support jamming against radar and communications threats. The output traveling wave tube (OTWT) is the final output stage of the Band 4 Transmitter’s Radio Frequency (RF) amplifier chain. For the current OTWT design, manufacturing yield cannot keep pace with the Navy demand for spares to replace failed OTWTs. The goal of this project was to assist in the mitigation of cost and delivery risk for Band 4 Transmitter OTWTs, which will benefit procurement of other bands of Transmitter OTWTs, such as the Band 5/6.
The main benefit of this effort was the improvement of the production yields of Band 4 OTWTs for the EA-6B Prowler aircraft. In the recent past, these yields were reported as less than 30%, presenting cost and delivery issues to the Navy. Improving yields of the current design as well as improving the readiness of potential replacement OTWT designs will significantly impact the availability of spare OTWTs for the Band 4 Transmitter. At the completion of this project, there was 100% yield on 2 OTWTs that were completed. The overall yield going forward is predicted to be at least 60%, which will be double the prior yields.
Four manufacturing improvements – a new insertion machine, e-beam welding, laser striping, and metalizing of support rods – were implemented at L-3 Communications, the OTWT manufacturer. The initial two modernized OTWTs successfully passed both electrical and antenna functional testing at L-3. Success of this project is achieved when the following two criteria are accomplished; one, PMA 234 approves the improved OTWT and, two, the OTWT is installed into the EA-6B Prowler aircraft. To gain PMA 234 approval, vibration qualification testing of the improved OTWTs has started at NSWC (Crane) in Crane, Indiana. The improved OTWTs are scheduled to be installed on the EA-6B Prowler aircraft in April of 2008.