Flight Crew Commercial
Distraction; Situational Awareness
ATC Issue All Types; Inflight Event / Encounter CFTT / CFIT
Air Traffic Control Issued Advisory / Alert; Flight Crew Returned To Clearance; Flight Crew Took Evasive Action
ATC Equipment / Nav Facility / Buildings
I was shooting the Fairbanks International ILS 20R approach and was between CIGNI and HOSAN.  I'm not sure of the exact altitude; but somewhere between 1;300-1;800 MSL on the glide slope the Tower on 118.3 radioed me a low altitude alert warning and said to climb immediately.  I put power in and immediately climbed losing the glide slope.  I had Ground contact at this point and I did not believe the Tower's warning that my altitude was too low; but I complied with their directions and climbed.  Once I climbed 300-400 feet; I could see the runway lights; so I continued my approach and made a normal safe landing on the runway.  The visibility issues were due to smoke and the visibility at the time was 2-3 SM.  After I taxied back; shutdown the plane; and unloaded my passengers; I called Fairbanks Tower to ask them about the low altitude warning.  When I told them that the needles were centered and it happened between CIGNI and HOSAN I was informed that the Tower's radar alert system sometimes gives erroneous readings and that between those 2 fixes on the ILS 20R was a common place for the erroneous warning to happen.  Having analyzed my response to this situation I think a better response to this event in the future would be to go missed on the approach.  I did not go missed because I was very familiar with this approach and I had ground contact at the point of the warning.  In the future I plan to climb anyway; go missed and come back and try a different approach the second time.
Pilot reported being advised of a Low Altitude Alert; climbing; seeing the airport visually; then landing.  Tower advised ATC sometimes gets erroneous alerts at the aircraft 's position.