Improved propulsion assembly for a multi-engine aircraft

A propulsion assembly (100) for an aircraft, particularly a multi-engine helicopter, comprising:

• at least one first engine (1) and a second engine (2) configured to operate in at least one standby mode,
• a primary air circulation device (30) configured to bleed air from the first engine (1) via a first bleed channel (310) and/or from the second engine (2) via a second bleed channel (320) to convey it to equipment of the propulsion assembly (100), and
• a secondary air circulation device (40) configured, when one of the first or second engines (1, 2) operates in the at least one standby mode, to bleed air originating from the other of the first or second engine (1, 2) not operating in standby mode and to convey it to the first or second engine (1, 2) operating in standby mode,
• wherein the secondary air circulation device (40) comprises a bypass device arranged on one of the first or the second bleed channel (310, 320), the first and the second bleed channel (310, 320) comprise a solenoid valve (311, 321) and a check valve (312, 322), the bypass device comprising a bypass channel (410) comprising a solenoid valve (411), a first end (410a) of the bypass channel (410) being in communication with said first or second bleed channel (310, 320) downstream of the check valve (312, 322) of said first or second bleed channel (310, 320), wherein the first and the second bleed channel (310, 320) are configured to bleed air from the first and the second engine (1, 2) at a bleed point (313, 323) of the first and the second engine (1, 2) respectively, the bypass channel (410) comprising a check valve (412) mounted in opposition to the check valve (312, 322) of the first and second bleed channel (310, 320), a second end (410b) of the bypass channel (410) being configured to inject air into the first or second engine (1, 2) operating in standby mode, at an injection point (414) distinct from the bleed point (313, 323), the bypass channel (410) comprising a limiter (415) arranged between the check valve (412) and the injection point (414), the limiter (415) being configured to regulate a flow rate of air flowing in the bypass channel (410).

A propulsion assembly (100) for an aircraft, particularly for a multi-engine helicopter, comprising:

• at least one first engine (1) and a second engine (2) configured to operate in at least one standby mode,
• a primary air circulation device (30) configured to bleed air from the first engine (1) via a first bleed channel (310) and/or from the second engine (2) via a second bleed channel (320) to convey it to equipment of the propulsion assembly (100), and
• a secondary air circulation device (40) configured, when one of the first or the second engine (1, 2) operates in the at least one standby mode, to bleed air originating from the other of the first or the second engine (1, 2) not operating in standby mode and convey it to the first or the second engine (1, 2) operating in standby mode,
• wherein the secondary air circulation device (40) comprises a bypass device arranged on one of the first or the second bleed channel (310, 320), the first and the second bleed channel (310, 320) comprising a three-way valve (311′) and a check valve (312), the bypass device comprising a bypass channel (410), a first end (410a) of the bypass channel (410) being in communication with said first or second bleed channel (310, 320) downstream of the check valve (312) of said first or second bleed channel (310, 320), a second end (410b) of the bypass channel (410) being connected to the three-way valve (311′), the three-way valve (311′) being movable between a first position allowing an air flow in said first or second bleed channel (310, 320) and preventing an air flow in the bypass channel (410), and a second position preventing an air flow in said first or second bleed channel (310, 320) and allowing an air flow in the bypass channel (410).

A propulsion assembly (100) for an aircraft, particularly for a multi-engine helicopter, comprising:

• at least one first engine (1) and a second engine (2) configured to operate in at least one standby mode,
• a primary air circulation device (30) configured to bleed air from the first engine (1) via a first bleed channel (310) and/or from the second engine (2) via a second bleed channel (320) to convey it to equipment of the propulsion assembly (100), and
• a secondary air circulation device (40) configured, when one of the first or the second engine (1, 2) operates in the at least one standby mode, to bleed air originating from the other of the first or the second engine (1, 2) not operating in standby mode and to convey it to the first or the second engine (1, 2) operating in standby mode,
• wherein the secondary air circulation device (40) comprises a bypass device arranged on one of the first or the second bleed channel (310, 320), the first and the second bleed channel (310, 320) comprising a solenoid valve (311, 321), the bypass device comprising a movable check valve (412′) arranged on the first or on the second bleed channel (310, 320), the movable check valve (412′) being movable between a first position allowing an air flow in said first or second bleed channel (310, 320) in a first circulation direction and preventing an air flow in a second circulation direction, opposite to the first direction, and a second position allowing an air flow in the second circulation direction and preventing an air flow in the first circulation direction.

A propulsion assembly (100) for an aircraft, particularly a multi-engine helicopter, comprising:

• at least one first engine (1) and a second engine (2) configured to operate in at least one standby mode,
• a primary air circulation device (30) configured to bleed air from the first engine (1) via a first bleed channel (310) and/or from the second engine (2) via a second bleed channel (320) to convey it to equipment of the propulsion assembly (100), and
• a secondary air circulation device (40) configured, when one of the first or the second engine (1, 2, operates in the at least one standby mode, to bleed air originating from the other of the first or second engine (1, 2) not operating in standby mode and to convey it to the first or the second engine (1, 2) operating in standby mode,
• wherein the secondary air circulation device (40) comprises a bypass device arranged on one of the first or the second bleed channel (310, 320), the first and the second bleed channel (310, 320) comprising a solenoid valve (311, 321), the bypass device comprising a blockable check valve (412″) arranged on the first or the second bleed channel (310, 320), the blockable check valve (412″) being configured to be blocked in an open position allowing an air flow in two circulation directions.