Airborne Research Interferometer Evaluation System

An upward and downward-pointing infrared interferometer producing high resolution spectra covering wavenumbers from 550cm-1 to 3000cm-1 mounted in the aft position in the radiometer blister.


ARIES is a Fourier transform spectrometer based on the Bomem MB100 interferometer, modified by ABB Bomem (Canada) for airborne use, with Met Office designed pointing optics, external black bodies and control electronics. Although designed, and primarily used, for airborne measurements ARIES can also be used for ground based work away from the aircraft.

ARIES flew for the first time in March 1996 on the Lockheed C-130, XV208 and was installed on the BAe 146-301 in April 2004. The schematics of the instrument is shown in the drawing below and the specifications are listed in the Table below.

Range 550 – 3000 cm-1
Resolution 1 cm-1 max OPD
Beamsplitter potassium bromide
Detectors MCT/InSb sandwich with Sterling cycle cooler
Views zenith, nadir-5° to nadir+55° (8 angles), hot and cold targets, selectable in flight
Scan rate >4 double-sided igms/sec. at 1 cm-1 resolution up to 64 igms/sec. at 16 cm-1
Field of view 2.5° full angle
Calibration 2 external, heated, stabilised, black body targets.
Noise NE δ T 0.2 K for 1-minute averaged spectra

ARIES schematic drawing

Schematic diagram of ARIES internal optics 


ARIES Optics ARIES Electronics
ARIES with starboard side removed showing electronics modules (top), detector/cooler unit (bottom right), heater controller (mid left) and folding/focusing optics (bottom left). ARIES with port side open showing electronics modules attached to side panel (bottom). The interferometer optics are hidden behind the gold coloured panel (top centre) but the orange glow of the HeNe counting laser can be seen past the forward end (left) of the panel.


Contact Alan Vance, Met Office

Additional information