Date: 201503
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Flight conditions: IMC
Weather elements / visibility: Rain; Turbulence
Light: Daylight
Aircraft: EMB ERJ 145 ER/LR
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Initial Approach
Airspace: Class B ZZZ
ATC / advisory: TRACON ZZZ
Aircraft component: Autoflight System
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Pilot Flying; First Officer
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Workload; Communication Breakdown; Confusion; Distraction
Second reporter function: Captain; Pilot Flying
Anomaly: ATC Issue All Types; Aircraft Equipment Problem Less Severe; Conflict Airborne Conflict; Deviation - Altitude Excursion From Assigned Altitude; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter Weather / Turbulence
Detector: Automation Aircraft Other Automation; Automation Aircraft TA; Person Air Traffic Control; Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Issued Advisory / Alert; Aircraft Automation Overrode Flight Crew; Flight Crew Became Reoriented; Flight Crew Overcame Equipment Problem; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Took Evasive Action
Contributing factors: Weather; Procedure; Human Factors; Aircraft
Primary problem: Ambiguous

Narrative: While on last leg of a 4-day trip on RNAV arrival and subsequent vectors to final approach course to ILS 8R. I was the First Officer (FO) and Pilot flying. We had a 100 knots tail wind on the Arrival and a significant tailwind from the west at this point. We were given vector of 060 degrees; maintain 5;000 feet until established localizer; cleared the ILS 8R. Outside of IF; I joined the LOC on FMS pink needles and then switched to GREEN needles. Then upon LOC intercept and given 190 KIAS until 9 DME. I deployed flight spoilers. We were slightly above glideslope and ATC told us to slow to 170 KIAS. I ordered gear down and flaps 22. Weather conditions were IMC in Heavy rain with significant tail wind. The Captain (Nonflying Pilot) noted another aircraft on TCAS nearby to our right side. Near the 9 DME passing through 3;000 we set MAP altitude 3;000 feet on Altitude alerter. I believe we were inside 9 DME when ATC suddenly told us to turn to heading 180 degrees and climb maintain 5;000 feet. The ambient noise level was louder due to aircraft configuration and ATC chatter. Captain asked ATC for clarification due to another aircraft near that side. We hesitated turning momentarily due to our concern with the close proximity of the aircraft to our right. I attempted to disengage Autopilot (AP) and manually fly the turn and climb; the AP would not initially disengage. I saw a red colored 'AP' on the PFD and hear loud 'Autopilot; Autopilot;' oral while ATC also attempted to talk but was blocked by oral warnings in cockpit. The AP oral warning 'Autopilot; autopilot;' continued to enunciate along with 'GlideSlope' and 'Bank Angle.' The aircraft attitude was in normal parameters. We attempted turning with heading bug but again AP would not work. Eventually AP disengaged and manually in the turn to the right; I heard TCAS; TA 'Traffic' enunciate once. We were then told to climb to 5;000 feet; heading 180 degrees; and then turn to something like heading 220 degrees. While I flew manually; the Captain attempted to reengage the AP and explained to ATC of what the situation was with AP problem. We climbed to 5;000 feet and eventually got AP reengaged momentarily but then it malfunctioned again. I manually flew the aircraft and ATC vectored us around back onto ILS 8R flown manually by me with no further complications. After landing while taxiing we did an Autopilot test and the test was successful.Upon landing ATC tower gave us a telephone number and Captain called TRACON.  The Supervisor said we lost spacing separation with another aircraft landing at a nearby GA satellite airport when we failed to stop descent at 4;000 feet. When we asked Supervisor why were instructed to turn 180 degrees; he stated that the final approach controller (still working his station) was attempting to insert another flight in front of us; but then the spacing did not work out. We suggested that we should have been given a Go Around instead of a vector so close to the ILS final approach fix at that critical phase of flight. Furthermore; our aircraft's abnormal automation behavior and interfering cockpit automation orals and conflicting ATC instructions to turn towards a nearby aircraft further complicated the situation in a critical; time sensitive condition of flight. The supervisor seemed to agree and understood the collective threats culminating into the situation. He said he would talk to the actual controller once he came off his station. And a report must be sent to FAA.The aircraft state was safe and in normal parameters during the vector to approach and initial approach intercept. The threats accumulated as we intercepted the localizer on the ILS 8R. Threats included:1. Weather: IMC; low ceiling and visibility; heavy rain. Strong tail wind with turbulence during STAR descent and transition to ILS 8R2. Other aircraft in unexpected close relative position to our aircraft.3. FO was using new TELEX 750 headset with foam ear plugs instead of the uncomfortable company issue non-sound suppression headset. Captain was using a commercial full-ear covering sound suppression headset.4. Radio chatter and louder ambient cockpit noise level due to aircraft slowing configuration while descending. Made it difficult to hear ATC clearly. FO should have increased volume on new headset when cockpit noise increased on the approach.5. Automation refused to quickly decouple and subsequent loud CAS Orals; TCAS TRAFFIC; bogus GLIDESLOPE and BANK ANGLE orals and Autopilot disconnect Oral made it very difficult to hear entire ATC message of instructions.6. The apparent ATC instructed level at 4;000 feet was not set into the Altitude Alerter while on the ILS glideslope. Flight crew could have been better at monitoring; verification and cross talk regarding ATC instructions. Flight Crew became very busy dealing with multiple threats in just a few seconds.7. ATC's attempt to insert another flight in front of us and give us vectors close to FAF in IMC towards nearby other aircraft should not have happened. We should have been instructed to execute a Go Around. In the future in same situation--I will tell ATC we are Going Around and not turn towards the other aircraft.8. We were not aware of altitude deviation (below '4;000 feet') until ATC informed us during the turn to 180 degrees. 9. Crew's last approach at end of a 4-day trip/ end of duty day. While we were ready for the trip to end and go home--We were not fatigued.I suggest several things to improve upon are illuminated by this event:1. Crew members should use sensory equipment of similar capability level. (i.e.; one pilot with an expensive noise cancelling headset and the other with a normal cost pilot headset that does not have noise cancelling. This concept is similar to the military's requirement that all flight crew have same generation of NVGs for vision. The air crew must have a similar sensory experience and expectation of crew mates hearing the ATC. Company should provide better more comfortable headsets so crew members would be inclined to use company issued headsets. I personally will no longer use the TELEX 750 in an EMB 135/145. It is just too noisy.2. ATC should be more cognizant of the impact on weather; airspace; and critical stage of flight on ILS in IMC; imperfect radio communications and cockpit automation oral distractions; on aircrew's ability to manage tasks and hear time sensitive maneuvering instructions. The attempt to have us go down and slow down with such a tail wind while ATC attempted to insert another flight in front of us and then vector us towards another nearby aircraft and the associated pilot cross talk; aircraft orals warnings; improperly performing automation and time needed to clarify ATC's instruction so close to FAF 3. Air crew should have set 4;000 feet in Altitude Alerter when it was given by ATC. But When I heard maintain 4;000 feet; we were already approaching 3;000 feet.In summary; this event is just the type of CRM/TEM Swiss Cheese accident chain of events taught in the school house. I will use it at my next recurrent training class discussion.


Second narrative: There were many threats starting with marginal weather and a high traffic environment. After being cleared and mostly configured for an approach we were given break off instructions that the crew could not verify due to one not having heard the full instructions. Could not get immediate confirmation from ATC and when we did the loud aircraft warning messages blocked ATC instructions. Timing of and amount of instructions and execution requirements made for a high workload that kept us from executing the instructions.I have to focus more on how to manage my workload in this type of environment. The sequence I choose will certainly impact the outcome of events.


Synopsis: An EMB-145 on an ILS was taken off the approach for traffic. The crew had difficulty understanding the Controller because the autopilot was issuing failure alerts and would neither turn nor disconnect. Eventually they complied but had a traffic conflict in the process.