The third prototype of the Russian fully import-substituted Russian aircraft SJ-100 with tail number 97003 is almost ready to take to the skies for flight tests.
Currently, frequency tests of the aircraft are being conducted at the Komsomolsk-on-Amur production site of PJSC "Yakovlev." These are the last tests before the aircraft begins flight tests, and they are necessary to avoid dangerous aeroelastic resonance vibrations—flutter—in flight.
The tests are conducted in three stages:
- studying aircraft vibrations in free flight conditions, with special attention to the connections of units, assembly quality, and the operation of rudders and ailerons;
- testing the remote control system, including checking all control paths, sensors, actuators, and other units;
- testing the landing gear, aimed at preventing the shimmy effect during takeoff and landing, that is, automatic wheel oscillations due to instability of straight rolling.
Frequency testing of the aircraft is a mandatory condition for aircraft type certification. They guarantee the safety and reliability of the machine—in this case, the import-substituted SJ-100—in operation.
After their completion, the aircraft will be able to enter flight tests, and the SJ-100 project itself will move towards its further commercialization.
It is worth noting that another instance of the import-substituted SJ-100 with tail number 97021 is also preparing for certification tests in Zhukovsky. It is entirely of domestic production, except for the engine: the Russian-French SaM146 was left to speed up certification. This aircraft has already passed frequency tests in Komsomolsk-on-Amur and flew to the Moscow region on its own in late April.
Read materials on the topic:
Aeroflot Plans to Lease More Than 300 MC-21s Instead of SJ-100 and Tu-214
Engine and Airborne Radio-Electronic Equipment Ready for the New Russian SJ-100 Airliner
