Last change of this page: 12 Jan 2017  

Deployment base.. Time period.. Description.. Principal investigators.. Partners.. Instruments.. Flights.. More information.. Press, media, photo gallery .. FX contact point ..

Mission acronym, title and status


"Oxidation Mechanism Observation"


Status:     Mission operation was successfully completed on September 4, 2015.  


HALO deployment bases

HALO was operated from different bases during this mission:

  • DLR Oberpfaffenhofen, Germany (Airport ICAO code: EDMO)
  • Paphos, Cyprus (Airport ICAO code: LCPH)
  • Gan, Maldives (Airport ICAO code: VRMG)


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Time period

The OMO mission with HALO consisted of two field campaigns: OMO-EU and OMO-Asia.

OMO-EU campaign phases:

Mission phase Dates HALO in ..
Preparation incl. EMI testing 24.11.2014-21.01.2015 Oberpfaffenhofen
Mission Oberpfaffenhofen 22.01.2015-27.01.2015 Oberpfaffenhofen
Dismounting of payload 28.01.2015-30.01.2015 Oberpfaffenhofen

OMO-Asia campaign phases:

Mission phase Dates HALO in ..
Preparation incl. EMI testing 26.05.2015-10.07.2015 Oberpfaffenhofen
Mission Oberpfaffenhofen 11.07.2015-20.07.2015 Oberpfaffenhofen
Mission Paphos Phase 1 21.07.2015-01.08.2015 Paphos, Cyprus
Mission Gan 01.08.2015-10.08.2015 Gan, Maldives
Mission Paphos Phase 2 10.08.2015-27.08.2015 Paphos, Cyprus
Dismounting of payload 28.08.2015-04.09.2015 Oberpfaffenhofen


Project description

HALO on the airport of Gan (Maldives) during the OMO-Asia campaign

The OMO aircraft measurement campaign addressed the "self-cleaning capacity" of the atmosphere. It focused on oxidation processes and air pollution chemistry downwind of South Asia during the summer monsoon. The self-cleaning mechanism converts natural and human-made pollutants into more soluble products that can be removed by rain. This is critical for air quality and climate change, both regionally and worldwide considering rapidly growing pollution emissions, especially in Asia.

The measurements took place in July and August 2015 in the upper troposphere at 10-15 km altitude. The goal was to study the influence of convective clouds and rainfall on atmospheric composition during the monsoon. While soluble gases and aerosol particles can rain out, the removal efficiency is poorly known. Monsoon clouds can have a strong and large-scale impact on atmospheric chemistry through the vertical redistribution of sunlight, pollutants and humidity. The chemical, transport and deposition processes are investigated to advance computer models and improve air quality and climate change calculations.

The German institutions of the consortium belong to the Max Planck Society, the Helmholtz Association and universities that have a track record in airborne atmospheric research, for example in the Indian Ocean Experiment, conducted in the dry season, to which the OMO measurements can be contrasted. The consortium has recently developed a comprehensive set of instrumentation for the HALO aircraft.

The flight patterns included tracks across the Arabian Sea, the Arabian Peninsula, the Indian Ocean and the Mediterranean Sea to study zonal and meridional concentration gradients and large-scale impacts of the monsoon. Vertical (stack) flights were performed in regions of particular interest, so that a range of atmospheric conditions could be analyzed and the extent of pollution layers investigated. The measurements document long-distance pollution transports and their influence on regional-to-global atmospheric composition and climate.


Principal investigators

Principal investigators:



  • Max-Planck-Institut für Chemie, Mainz (MPI-C)
  • Forschungszentrum Jülich (FZJ)
  • Karlsruher Institut für Technologie (KIT)
  • Universität Bremen
  • Universität Heidelberg
  • Universität Wuppertal
  • Deutsches Zentrum für Luft- und Raumfahrt, Institut für Physik der Atmosphäre (DLR-IPA), Oberpfaffenhofen
  • Deutsches Zentrum für Luft- und Raumfahrt, Einrichtung Flugexperimente (DLR-FX), Oberpfaffenhofen


Scientific instruments and payload configuration

List of scientific instruments for the mission:

Scientific instrument acronym Description
(species measured)
Principal investigator Institution Remarks
HORUS OH/HO2/NO2 Hartwig Harder MPIC Mainz  
AIR LIF OH/HO2/NO2 Frank Holland FZ Jülich  
PERCEAS RO2 Lola Andrés Hernández Univ. Bremen  
SR Actinic Flux Birger Bohn, Manfred Wendisch FZ Jülich, Univ. Leipzig  
FAIRO Fast ozone measurement Andreas Zahn KIT Karlsruhe  
KMS OVOC Andreas Zahn KIT Karlsruhe  
MGC NMVOC Jonathan Williams MPIC Mainz  
TRIHOP Total Peroxides, H2O2 / CO, HCHO, CO2 Horst Fischer MPIC Mainz  
IPA-NOY NOY Helmut Ziereis DLR-IPA other name: AENEAS
PAN-MS SO2, HNO3 Hans Schlager DLR-IPA  
GFR / GSB Gasflaschen-Rack, Gassicherheitsbehälter Hartwig Harder, Frank Holland, Lola Andrés Hernández MPIC Mainz, FZ Jülich, Univ. Bremen  
CPC Condensation particle counter Hans Schlager DLR-IPA  
PR Pumpen-Rack Hartwig Harder, Frank Holland, Lola Andrés Hernández MPIC Mainz, FZ Jülich, Univ. Bremen  
MIRAH VOC + isotopes Ralf Koppmann Univ. Wuppertal  
miniDOAS Differential Optical Absorption Spectroscopy Klaus Pfeilsticker Univ. Heidelberg  
BAHAMAS HALO basic data acquisition system Andreas Giez DLR Flugexperimente  


Cabin and exterior configuration of HALO for the mission:

HALO cabin layout for OMO

HALO exterior configuration for OMO


HALO flights for this mission


Date Takeoff time (UT) Landing time (UT) Total flight time
FromToType Comment
D-ADLR21.01.201510:45:0013:00:002.250EDMOEDMOFlight test OMO-EU
D-ADLR24.01.201510:15:0013:40:003.417EDMOEDMOMission flight OMO-EU
D-ADLR25.01.201509:30:0015:10:005.667EDMOEDMOMission flight OMO-EU
D-ADLR27.01.201510:30:0015:25:004.917EDMOEDMOMission flight OMO-EU



Date Takeoff time (UT) Landing time (UT) Total flight time
FromToType Comment
D-ADLR10.07.201507:40:0009:30:001.833EDMOEDMOFlight test OMO-Asien
D-ADLR13.07.201509:35:0011:55:002.333EDMOEDMOMission flight OMO-Asien
D-ADLR16.07.201510:00:0012:40:002.667EDMOEDMOMission flight OMO-Asien
D-ADLR21.07.201509:00:0012:25:003.417EDMOLCPHMission flight OMO-Asien
D-ADLR25.07.201505:55:0011:10:005.250LCPHLCPHMission flight OMO-Asien
D-ADLR28.07.201506:10:0014:00:007.833LCPHLCPHMission flight OMO-Asien
D-ADLR01.08.201505:50:0014:35:008.750LCPHVRMGMission flight OMO-Asien
D-ADLR06.08.201502:00:0006:40:004.667VRMGOBBIMission flight OMO-Asien
D-ADLR06.08.201507:45:0012:55:005.167OBBIVRMGMission flight OMO-Asien
D-ADLR08.08.201507:30:0011:25:003.917VRMGVRMGMission flight OMO-Asien
D-ADLR09.08.201501:50:0006:30:004.667VRMGOBBIMission flight OMO-Asien
D-ADLR09.08.201507:40:0012:35:004.917OBBIVRMGMission flight OMO-Asien
D-ADLR10.08.201504:50:0009:35:004.750VRMGOBBIMission flight OMO-Asien
D-ADLR10.08.201510:55:0014:30:003.583OBBILCPHMission flight OMO-Asien
D-ADLR13.08.201506:00:0014:55:008.917LCPHLCPHMission flight OMO-Asien
D-ADLR15.08.201505:50:0015:10:009.333LCPHLCPHMission flight OMO-Asien
D-ADLR18.08.201506:15:0015:10:008.917LCPHLCPHMission flight OMO-Asien
D-ADLR23.08.201505:55:0012:40:006.750LCPHLCPHMission flight OMO-Asien
D-ADLR25.08.201506:05:0014:35:008.500LCPHLCPHMission flight OMO-Asien
D-ADLR27.08.201508:40:0014:35:005.917LCPHEDMOMission flight OMO-Asien


More information

Scientific background and links to more information


Campaign reports and stories:


Press releases, media etc.

Press release German Embassy Nicosia (August 11, 2015):
German research aircraft in Cyprus

Press release Max-Planck-Institut für Chemie (May 17, 2015)
Flying 100,000 kilometers through the monsoon

Report in "in-cyprus" (August 14, 2015):
Monsoon research in Paphos

Report on DLR-FX homepage (August 6, 2015):
HALO auf Kampagne "OMO-Asien"

Press release DLR (July 17, 2015):
Forschungsflugzeug HALO: Auf der Langstrecke für Messungen im asiatischen Sommermonsun


Contact point at FX for this mission

HALO Project Management: Martina Hierle

Postal address:
DLR Oberpfaffenhofen
Flugexperimente (FX)
Münchener Str. 20
82234 Weßling

Office phone:
+49 (0)8153 28-1792