T-4000 likely candidate for use on the F-35 fighter

There has been comment on this topic before, on this blog, but it's nice to see "official" confirmation.

Panel Step/Gap Mismatch Measurement - Summary for phase 2 funding

Title
Panel Step/Gap Mismatch Measurement
SBIR Topic Number
AF082C-001
Summary Report Type
Phase I Summary
Summation
In the Phase I work, we demonstrated the feasibility of the TD-THz method to measure the dimensions of the ground-plane step and gap through otherwise opaque boots and coatings. We acquired step and gap data on coupons with realistic boots, coatings and substrates to demonstrate the accuracy and precision of the sub-surface TD-THz measurement. We developed a hand-held TD-THz step and gap mismatch measurement system concept to be prototyped in Phase II. This system concept will be able to measure the sub-surface ground-plane step and gap dimensions on all 19 types of seams of panels on the F-35 aircraft. The first application of the measurement system will be in the OEM manufacture of the F-35. Later, the step/gap measurement system can be used in a depot environment to set the step and gap of pre-coated replacement panels, and then eventually by Air Force field service personnel. The TD-THz step/gap mismatch system is based on our T-RayTM 4000 TD-THz instrumentation platform. A hand-held high speed plug-in TD-THz line scanner will acquire a B-scan across a seam and rapidly calculate the step and gap dimensions. The proposed instrument will be able to measure substrate step/gap dimensions through a variety of coating and paints. The TD-THz measurement process is suitable for both composite (conductive and non-conductive) and metallic substrates. TD-THz reflection non destructive evaluation imaging is like an electromagnetic analog to a laminographic ultrasound B-scan, but with several advantages: The TD-THz measurement is non-contact, requires no special preparation of the surface, can be used to determine the dimensions of small structures with precision better than one thousand of an inch.
Anticipated Benefits
Upon successful completion of Phase II, the proposed TD-THz inspection system will provide the Air Force with a highly capable non-destructive, non-contact, single-side inspection method for the determination of subsurface step/gap dimensions on aircraft doors and panels. The Phase II prototype system will be capable of accommodating all configurations required to be measured on the full-scale aircraft, including the various material suites, joint designs, and contours.
Disclaimer: The appearance of a report or a hyperlink does not constitute endorsement by the Department of Defense or the Department of the Air Force. Distribution A: Approved for public release; distribution unlimited.

(thanks to bucktailjig)