Indonesia's National Transportation Safety Committee (NTSC) has issued some immediate recommendations to how demonstration flights should be conducted while investigations into the May crash of the Sukhoi Superjet 100 continue.
To address the safety issues that were identified, the NTSC is recommending that Indonesia's directorate general of civil aviation (DGCA) ensure that all aircraft on demonstration flights operate within a "published minimum safe flight altitude".
It also wants Sukhoi to review its procedures for the preparation and operation of demonstration flights and if needed, make the appropriate changes.
NTSC is also recommending that the manufacturer arrange additional training for crew who will be conducting demonstration flights, especially for those operated in mountainous regions.
The DGCA and Sukhoi should also ensure that a copy of the crew and passenger manifest are kept on the ground, at the ground handling and operation service office, before each flight, says the NTSC.
The SSJ100 aircraft, with the serial number 95004 and tail number 97004, which crashed on 9 May was scheduled for a 30-minute demonstration flight. It had been due to take off from Jakarta's Halim Perdana Kusuma Airport before heading to Pelabuhan Ratu, an area in West Java, and then return to the airport.
Radar contact with the aircraft, however, was lost about 30 minutes after take-off, shortly after it requested to descend to 6,000ft (1,829m). The aircraft wreckage was later found on a near-vertical mountainside on the eastern side of Mount Salak, at an elevation of about 6,100ft.
In its initial investigations, NTSC said it could not find a copy of the passenger manifest and aircraft documents, which were kept and carried on board by a staff who was also a passenger on the fatal flight.
The aircraft had also been certified by Russia's ministry of industry and trade to be safe for operations under the conditions that the aircraft would be maintained and operated according to regulations.
NTSC also confirms that both pilots operating the aircraft each held a valid test pilot licence issued by the Russian Federation.
Meanwhile, both the aircraft's cockpit voice recorder and flight data recorder have been retrieved and Indonesian and Russian authorities have formally signed a cooperation agreement over the investigation.
None of the 45 people on board survived.