GRICAS getting ready for take-off



On Wednesday 16th and Thursday 17th of November 2017, GRICAS project took a major step towards 2017’s in-flight demonstration of its operational concept

Indeed, while on Wednesday 16th morning, the preliminary integration activities completed successfully in ELTA facilities. Wednesday afternoon was dedicated to the visit of a test airplane that is expected to be used in 2017 demonstrations. Finally, on Thursday 17th morning, ELTA hosted GRICAS Critical Design Review in presence of all the industrials of GRICAS consortium (STMicroelectronics, ELTA, Pildo Labs and Thales Alenia Space) and of one of the GSA reviewer and with the participation by phone of the second GSA reviewer.

Preliminary integration

Since beginning of October we have been testing the prototype of GRICAS ELT-DT based on SGB, transmitting alert messages and receiving them on Thales MEOLUT. The tests went fine and we decided to go further. Thus, on Wednesday 16th of November 2017, GRICAS project took a major step towards the preparation of 2017’s in-flight demonstration of its operational concept to answer to new ICAO recommendation regarding Autonomous Distress Tracking. Indeed, the preliminary integration activities completed successfully in ELTA facilities. Those activities consisted in integrating the prototype of GRICAS ELT-DT developed by ELTA, the Onboard Demonstration Platform (ODP, simulating the Beacon Activation Logic for automatic activation by avionic and offering the manual activation by crew function) developed by PildoLabs and the MEOLUT SAR antenna developed by Thales Alenia Space, and then testing a distress scenario.

The integration of the mechanical interfaces succeeded and allowed the teams to perform successfully an end-to-end test of a distress scenario as follow:

  • The GRICAS ELT-DT (23 HexID: 9C74000040175D565DC68E9) was on operational status “ARMED”.

  • The test engineer pressed the button on ODP for “Automatic activation by avionic : unusual attitude”.

  • The GRICAS ELT-DT received the trigger.

  • The GRICAS ELT-DT switched from operational status “ARMED” to “ON: Alert” and started transmitting a distress message of ELT-DT based on SGB as defined in GRICAS OCD (see my post on CWG regarding messages content and structures for ELT-DT based on FGB and SGB)

  • The Thales Alenia Space test MEOLUT (based in Thales Alenia Space facilities) received, processed and decoded correctly the distress messages.

A second set of tests was performed with simulated RL Messages:

  • The test engineer simulated the different types of RLM defined in GRICAS operational concept and sent them to the GRICAS ELT-DT software (getting around the GNSS receiver of the beacon)

    • Automatic cancellation acknowledgment

    • Manual cancellation acknowledgment

    • Remote Activation

    • Remote De-activation

And also the Type-1 acknowledgment defined in Galileo RLS documents but not used in GRICAS operational concept.

  • The GRICAS ELT-DT correctly identified and processed the RL Messages including its 23HexID depending on their type:

    • Automatic cancellation acknowledgment: the beacon had been triggered and cancelled with an automatic trigger by avionic, it stopped transmitting.

    • Manual cancellation acknowledgment: the beacon had been triggered and cancelled with a manual activation via RCP, it stopped transmitting.

    • Remote Activation: the beacon started transmitting.

    • Remote De-activation: the beacon stopped transmitting.

    • Type-1 acknowledgment: the beacon received, processed and decoded the RLM and logged it on its RCP.

A third set of tests was performed consisted in direct reception of the GRICAS ELT-DT distress message by a MEOLUT simulator (an USRP to digitalized the RF signal transmitted by the beacon and a computer with the MEOLUT software to process the digitalized signal). Those tests completed successfully as well, they can be considered as a first step towards homing testing on SGB modulation.

Figure 1: Integration of GRICAS ELT-DT, its RCP and the ODP (emulator of avionic and automatic triggers)