A system for synchrophasing a multi-engine aircraft, comprising: a phonic wheel, the phonic wheel comprising a plurality of circumferentially uniformly-spaced first position markers disposed on an outer circumferential surface of the phonic wheel and a second position marker disposed on the outer surface, the second position marker disposed circumferentially closer to a selected one of the first position markers than to the remaining first position markers and being indicative of a reference position of a propeller of an engine of the aircraft; and a sensor adjacent the phonic wheel and configured for producing a signal comprising a plurality of signal pulses in response to sensing a presence of the first position markers and the second position marker, one of the phonic wheel and the sensor configured to rotate relative to the other of the phonic wheel and the sensor; characterised in that the system further comprises: a control system communicatively coupled to the sensor for obtaining the signal, and configured for: determining, based on the plurality of signal pulses, an expected delay between two subsequent pulses of the plurality of signal pulses, the expected delay representative of the spacing of the plurality of first position markers; identifying from within the plurality of signal pulses a particular pulse associated with the second position marker, the particular pulse having a delay shorter than the expected delay; determining, based on a particular time at which the particular pulse associated with the second position marker was produced, that a rotational position of the propeller corresponds to the reference position at the particular time; and performing at least one synchrophasing operation for the aircraft based on the rotational position of the propeller. a phonic wheel, the phonic wheel comprising a plurality of circumferentially uniformly-spaced first position markers disposed on an outer circumferential surface of the phonic wheel and a second position marker disposed on the outer surface, the second position marker disposed circumferentially closer to a selected one of the first position markers than to the remaining first position markers and being indicative of a reference position of a propeller of an engine of the aircraft; and a sensor adjacent the phonic wheel and configured for producing a signal comprising a plurality of signal pulses in response to sensing a presence of the first position markers and the second position marker, one of the phonic wheel and the sensor configured to rotate relative to the other of the phonic wheel and the sensor; characterised in that the system further comprises: a control system communicatively coupled to the sensor for obtaining the signal, and configured for: determining, based on the plurality of signal pulses, an expected delay between two subsequent pulses of the plurality of signal pulses, the expected delay representative of the spacing of the plurality of first position markers; identifying from within the plurality of signal pulses a particular pulse associated with the second position marker, the particular pulse having a delay shorter than the expected delay; determining, based on a particular time at which the particular pulse associated with the second position marker was produced, that a rotational position of the propeller corresponds to the reference position at the particular time; and performing at least one synchrophasing operation for the aircraft based on the rotational position of the propeller. determining, based on the plurality of signal pulses, an expected delay between two subsequent pulses of the plurality of signal pulses, the expected delay representative of the spacing of the plurality of first position markers; identifying from within the plurality of signal pulses a particular pulse associated with the second position marker, the particular pulse having a delay shorter than the expected delay; determining, based on a particular time at which the particular pulse associated with the second position marker was produced, that a rotational position of the propeller corresponds to the reference position at the particular time; and performing at least one synchrophasing operation for the aircraft based on the rotational position of the propeller.