HALOX (HALogen OXide monitor) – Instrument adaptation from balloon to aircraft

On behalf of the Forschungszentrum Jülich GmbH enviscope has been incorporated to the design team of an airborne stratospheric ClO and BrO monitor.

A former balloon borne instrument HALOX was completely redesigned and improved for measurements aboard the Russian Stratospheric Aircraft "Geophysica M55".

The instrument with a total weight of 130 kg was built on a mounting plate of aluminium with only four attachment screws to the aircraft underwing pod. It was moulded from a high-strength aluminium alloy plate.

Below the mounting plate two analysis axes for fluorescence resonance measurements were designed in interchangeable modules on mounting tracks.

The modules have been connected with special attachment clamps and bolts to allow disassembly of a complete analysis axis in short time. This is essential to get access to the fluorescence lamps and PMT for calibration work and maintenance.

The design work of the modules was done by enviscope engineers according to the input of the Jülich scientists. In close co-operation with the engineers of other disciplines like fluid-dynamics, electronic and the manufacturing workshop at the research establishment, the final design was adjusted to the multiple scientific and technical constrains to achive the desired properties of the measurement cells.


On top of the mounting platform a "gas-deck" and an "electronic-box" was designed. The gas-deck was made to be removable from the system even if the instrument is installed to the aircraft underwing pod. The electronic box controls the whole instrument.

Again enviscope designed the mechanical structure of the box in close co-operation with the electronic department.

The design was made to be lightweight, shielded with precautionary EMI protection, well accessible and should host all elements like EMI filters, electrical connectors to the aircraft, power supplies, computer, controller and housekeeping sensors.

One of the key activities from enviscope during the development process was the preparation of documents for the subsequent certification of the instrument.

The technical documentation consisting of drawings, a complete stress report and mechanically and electronically test procedures was examined by the Russian Design Engineers responsible for the certification.

The first integration campaign took place in Moscow in Oct. 2001.

Later on, we assisted the first scientific employment of the instrument during ENVISAT and EUPLEX Campaigns.

For detailed information about HALOX and EUPLEX, please contact Dr. Fred Stroh, Research Centre Jülich.