The FCAS-III/ CNC-III instrument was designed to
perform both particle measuring/counting functions of the original FCAS
and CNC instruments on lightweight platforms (balloons, remote aircraft).
The accuracy, precision and response time of this instrument are the same
as those indicated previously for the FCAS and CNC.
Fundamentally the FCAS-III/ CNC-III is identical to the FCAS and CNC
except there is no impactor and the instrument is cooled via an air duct.
The air duct is connected to an air scoop (or a pump in the case of a
balloon) which mounts on the aircraft skin.
The FCAS-III/ CNC-III passed the Lockheed design review in 1996 and has
successfully participated on one NASA sponsored ER-2 test flight. The
instrument structure is comprised of sheet metal (2024-T3 Clad and
bent parts 6061-T6 as per Lockheed/Martin engineer Greg Prince) which is
joined using NAS standard rivets in addition to 7075-T6 machined parts
(See Figure 3). All fasteners are NAS/MS standard. Where parts
are tapped thread inserts are used (self-locking heli-coils).
Weight: 54 lbs.
Power: 2 amps @ 120VAC (400 Hz)
8 amps @ 28VDC