News & Events

28 juin 2023

LEMON Lidar integration in the Safire ATR42 aircraft and test flights achieved

Instruments integration in the Safire ATR42 aircraft

Thanks to the joint efforts of LEMON partners CNRS, University of Bergen, SpaceTech, Safire and Onera, the instruments (in-situ commercial CRDS with its dedicated calibration setup, lidar and frequency reference) integration in the Safire ATR42 aircraft was successfully achieved mid-May 2023 in Toulouse, France.

The integration process raised some challenges. For example, the LEMON team members had to deal with the weight of the lidar instrument and its high energy consumption, which are linked to the instrument intrinsic ambition to be able to perform integrated-path DIAL from the aircraft as well as ground-based DIAL. Further mechanical or instrumental issues were successfully tackled as well, which allowed LEMON to proceed to the launching of the airborne tests starting in the first week of June 2023.

LEMON tests flights in June 2023

The LEMON demonstration flights onboard the Safire ATR42 took place from Francazal near Toulouse between 30 May 2023 and 10 June 2023. Flights took place in the South of France, over the Mediterranean coast and sea (Gulf of Lion), over the Gulf of Biscay, and over the South of the Toulouse region.

The test campaign had a twofold goal: first, to allow a first implementation and testing of the Lidar in airborne environment, to analyse the system current limitations in such environment. Second, to capture the different isotopic fingerprint of water vapor of the marine and land boundary layer for atmospheric science using the commercial in situ CRDS instruments.

Flight plans had been defined between the LEMON partners and Safire such as to tackle the campaign objectives, although the final flight plans were minted 48 hours before flight depending on the weather forecast. Indeed, the campaign benefitted from daily weather briefing and dedicated air traffic control system.

The campaign had to deal with stormy weather and cloudy conditions, which are no optimal conditions for the measurements. Nevertheless, several science flights could be performed (see Table below), and IP-DIAL acquisitions addressing HDO could be successfully performed, which is a unique capability of the LEMON Lidar instrument.

DateDepartureArrivalFlight nameTotal hours
23/05/202314h3015h35EMI Flight test1,1
26/05/202313h0014h10Test Flight1,2
02/06/202310h0011h12Test Flight1,2
06/06/202312h0013h12Test Flight1,2
07/06/202313h1216h36Science Flight Biscay3,4
08/06/202312h0014h54Science Flight CRA LMZ2,9
09/06/202314h0016h35Science Flight Lion2,6
10/06/202314h0016h30Science Flight Lion2,6

Partners gained lots of learnings from this campaign. Valuable scientific results will be published in the coming months. Also, LEMON gathered key experience that will be useful to similar future campaigns.

Partners will process and analyse the data in the coming weeks and months, and will make their best effort to show some preliminary results during the LEMON Final Project Public Workshop, which will take place as an online event on Tuesday, 11th July 2023, from 17:00 to 18:00 (CEST) – Registration is still open, click here:

To read further about the LEMON instrument airborne demonstration, refer to the dedicated article in the LEMON Newsletter n°6 available here:

Figures: (Top): LEMON partners in front of the Safire ATR42 aircraft during the airborne campaign in June 2023.

(Bottom left): LEMON Lidar inside the Safire ATR42 aircraft.

(Bottom right): In situ sensor and calibration setup.