Date: 201502
Local time of day: 1801-2400
Location: ADS.Airport, TX
Flight conditions: VMC
Light: Night
Aircraft: Gulfstream IV / G350 / G450
Operator: Corporate
Operating under: Part 91
Flight plan: IFR
Flight phase: Initial Approach
Airspace: Class E D10
ATC / advisory: TRACON D10
Aircraft component: Autoflight System
Component problem: Improperly Operated
Reporter organization: Fractional
Reporter function: Pilot Flying; Captain
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Situational Awareness; Human-Machine Interface; Distraction; Communication Breakdown
Second reporter function: Captain; Pilot Not Flying
Anomaly: Inflight Event / Encounter CFTT / CFIT
Detector: Automation Air Traffic Control; Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Issued Advisory / Alert; Flight Crew Became Reoriented
Contributing factors: Human Factors
Primary problem: Human Factors

Narrative: While on approach to ADS; we were set up for and expecting a visual to runway 33 with the ILS as a backup. About 15 miles from the airport approach informed us that the runway had changed and to expect the visual to runway 15. He gave us direct to JERIT and a descent to 2;000 feet. The Pilot Monitoring (PM) changed the runways in the FMS but we did not have time to set up the ILS. As we approached JERIT (the final in the ILS 15) While level at 2;000 feet I disengaged the autopilot to keep from smart turning at JERIT before we had clearance for the visual. The PM asked if I would like the ALTITUDE ALERT set to field level. I said OK but really didn't know why he asked this question. In retrospect I should have questioned the selection.  Intent on searching for the field altitude dropped out of my scan and at about 4 miles from the field we got a 1;000 foot call from the EGPWS I reset the Altitude Alert Display (AAD) to 1;500 feet to stay above 1;000 feet AGL just as ATC said they had an altitude alert and asked if we had the field in site.  We said we were correcting and had the field in site and he cleared us for the visual approach.  Since we were in the turn inside of JERIT approaching thee miles I remained at 1;500 feet and made an uneventful landing.In my self-review of this event I relearned a couple of things.  We got a runway change close in and that put us into a time compression situation.  Since we were coming in from the north slowing; configuring and getting the runway changed in the FMS was no small task.  While the PM managed to reset the FMS we were too busy to reset the courses and minimums; much less brief the approach; this didn't concern me too much since the conditions were VMC; but do I try to have backup NAV to any airport I fly into.  Alternative actions could have been to ask to land on runway 33 anyway; the winds were not prohibitive and the airport was not busy. If they demanded we use runway 15 we could have asked for delaying vectors until we were fully set. Struggling to find the airport in a sea of lights in a large metropolitan area is difficult at best. It's best to stay on the automation to protect yourself from things dropping out of your scan.  If I had selected heading; I would not have had to concern myself with the airplane turning prematurely and stayed with the automation and been altitude protected. Finally; if the PM recommends a change to the flight panel that doesn't sound quite right; question him.  My intent in the future is to request an instrument approach into large lighted metro areas at night if it is available.


Second narrative: While on vectors to visual approach for Runway 15 (ADS) at night; I was eyes outside looking for the airport. ATC assigned altitude was 2;000 feet. ATC said to us 'low altitude alert'. I then saw the airport and called it in sight. Aircraft was at 1;500 feet MSL. ATC then cleared us for visual approach and we landed with no issues.Use auto-pilot with altitude hold until runway in sight.


Synopsis: A Gulfstream IV flight crew inbound to ADS were cleared direct to JERIT and given a late runway change to land Runway 15 vice 33 as planned; maintain 2;000 feet. As the Pilot Monitoring (PM) programmed the changes the reporter Pilot Flying (PF) disconnected the autoflight to prevent undesired autoflight directed course and/or vertical navigation directed changes during the reprogramming. While proceeding direct the PM asked if he should set the altitude alert to field elevation? Notwithstanding they had not been cleared to a lower altitude or for an approach; the PF acceded to the request. Shortly thereafter ATC issued a low altitude alert warning.