B737-700
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 458
Distraction
ATC Issue All Types; Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
General None Reported / Taken
Procedure
While conducting the CAT II SA XXL into ZZZ we experienced momentary Flight Path symbol and Flight Guidance Cue (AIII mode) movement due to an aircraft departing on our runway as we were inside a five-mile final. This was obviously distracting while conducting an approach to a runway with a reported RVR of 1; 600 feet (I believe). My question is; why was the ILS Critical area not protected? It is my understanding that if the weather is less than 800 and/or two miles visibility; this area should be protected while aircraft are inside the OM or the fix used in lieu of. We have another question regarding protection of the ILS Critical area in ZZZ1. We were operating Flight XXXX; ZZZ1-ZZZ2. ZZZ1 weather was reported as 200 broken 1/4 mile visibility. We called Ground Control for taxi. 'Taxi Runway XX via U and W; report turning on to W.' There was no mention of 'hold short of the ILS Critical area.' Again; why not? If ATC does not specifically state a 'hold short' clearance then we are cleared to the runway hold short markings. My reason for submitting this [report] is to help me and possibly others understand the purpose of the ILS Critical Area. In advance; thank you for providing more clarity on this issue.
B737-700 Captain reported a momentary lost of flight path guidance while conducting an ILS approach at the same time a flight was departing from the approach runway.