Widebody; Low Wing; 2 Turbojet Eng
Flight Crew Air Transport Pilot (ATP)
Confusion; Training / Qualification
Deviation - Altitude Overshoot; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
General None Reported / Taken
Chart Or Publication; Procedure
The flight to CYHM was turbulent and we never made it to the planned cruising altitude due to turbulence. The arrival weather was approximately a 300 ft ceiling and around 4000 meters visibility and winds gusting from 25-30 knots at approximately 80-90 degrees off of runway heading. I was sitting in the Jumpseat as an additional crewmember for the flight. The conditions in the cockpit were loud and I was unable to hear much of what was being said between the pilot flying and the pilot monitoring. I knew the planned approach was the ILS to runway 12. I did not hear much of the brief due to the noise in the aircraft. As we proceeded into the terminal area; we were cleared to the APGOM fix and cleared for the ILS. Again; I did not hear much of what was being said cross-cockpit between the PM and the PF when given the approach clearance. I did catch that the PF wanted to make sure that the aircraft was stable for the approach as early as possible. I wholly agreed with this philosophy due to conditions at the field. The approach was flown to a successful landing. After the fact I was informed by the Line Check Airman that the aircraft descended to 2200 ft (the min altitude for the no-pt (No Procedure Turn) routing) when it should have been at 2700 ft (the MSA for the sector we approached from and/or the minimum altitude for the procedure turn routing). The No-PT routing minimum altitude of 2200 ft is confusing when the MSA is 2700 ft. Additionally; the APGOM fix is depicted on the plan view of the approach plate; but not the profile view; making it difficult to determine what the minimum altitude is for that fix when cleared direct versus given the No-PT routing. The CAT-II ILS plate shows a No-PT routing from the same fix; but with a minimum altitude of 2700 ft. The approach plate is ambiguous for what altitude should be maintained when cleared to the APGOM fix and the approach.
Air carrier Relief Pilot reported descending to 2200 feet after being cleared for the CYHM ILS Runway 12 direct APGOM. Pilot cited confusion as to the allowable minimum no procedure turn (NoPT) altitude and noted a disparity between the ILS Runway 12 NoPT (2200 feet) and ILS CAT II Runway 12 NoPT (2700 feet) altitudes.