The first production import-substituted MS-21-310 made a non-stop flight from Irkutsk to Zhukovsky in 5 hours and 50 minutes. The airliner covered about 4.2 thousand km — approximately 400 km more than the declared maximum range of 3.8 thousand km.
"Pervyy Tekhnicheskiy" explained why the flight performance figures "on paper" do not match the actual MS-21 flight.
To begin with, on the OAK website, the passport range of the MS-21-310 is indicated for an aircraft with a commercial load. This refers to a variant with passengers and baggage, as well as the necessary fuel reserves. A ferry aircraft has a completely different take-off weight.
On the flight from Irkutsk to Zhukovsky, the airliner flew without passengers and baggage. The absence of commercial load significantly reduces the weight of the aircraft, and therefore, fuel consumption. The freed-up weight can be used to increase the fuel reserve or achieve lower consumption with the same reserve.
Fuel Reserve Also Weighs a Lot
In addition, on a commercial flight, part of the fuel must remain untouched. The aircraft must have a reserve for prescribed procedures, including diversion to an alternate airfield and holding. During ferrying, the requirements and route calculation differ.
The wind could also have played a role. Since the MS-21-310 flew to Zhukovsky at an altitude of about 12.1 km from east to west, the tailwind component of the air flow increased the ground speed. The aircraft continued to operate normally with PD-14 engines.
Range with Load Will Increase Further
Moreover, the initial range of the MS-21 of 3800 km is only the starting point of the aircraft's development, not the limit of its capabilities, explained aviation expert Roman Gusarov to "Pervyy Tekhnicheskiy". He recalled that even the Boeing 737 initially had small flight range indicators.
Therefore, a flight of 4.2 thousand km does not mean that the passport range of the MS-21-310 is underestimated. Exactly 3.8 thousand km is the calculated indicator for an aircraft with commercial load and established operational reserves.
A ferry flight without passengers and baggage takes place under fundamentally different conditions, so directly comparing the two figures is incorrect.
Former Airbus A320 pilot Andrey Litvinov is more categorical. He believes that airlines may simply refuse the airliner due to economic unprofitability. Then the budget will have to subsidize the airliners for airlines to use them.
One of the reasons for the current flight range of the MS-21-310 is said to be overweight wings. However, aviation expert and blogger SkyExpert refuted this point of view.