Narrative:

I was the first officer on a saab 340A from msp to stc and was the PF. After departure from msp we were cleared direct to stc at 4000 ft MSL by msp. We were aligned with the extended localizer course, so I started tracking the localizer for the ILS runway 31 at approximately 30 NM out. We could see prominent stc landmarks from 30 NM out. At approximately 20 NM out of stc, ATC cleared us for the visual approach to runway 31 and advised us of numerous targets in the vicinity of stc. We had the TCASII set to the 20 NM range and could see several targets in the area at various altitudes. The captain was transmitting our intentions on CTAF and we heard at least one aircraft say he was holding at the OM. At this time we were indicating 240 KIAS and at 4000 ft. The CTAF frequency was busy with stc traffic calls. The captain asked the aircraft at the OM what his intentions were: his reply was to the effect that he would continue holding. At approximately 10 NM from the OM, the captain decided to cancel IFR. I turned the autoplt off and was flying. By now the TCASII was displaying multiple targets close in and so close to each other, it was hard to pick out at what altitude they were at. We were flying into the sun. At approximately 5 NM from the OM, we got a TA for the aircraft off our left and below us. The captain said to level off until we see the traffic. While the TA occurred, the captain was asking the cessna traffic what he was going to do, which he responded he would climb to get out of our way. The captain told the cessna to turn south, away from us and not to climb as we were above him. Immediately following his transmission, we got the RA 'climb.' I was looking outside and pitched up to 10 degrees and added power. Soon after, I pitched to 20 degrees up and checked my power at 100%. I see the C172 pass under the left side slightly below us and -300 ft showed on the TCASII, about 1/4 mi, if that. After sighting the traffic I reduced power and leveled off. We configured the aircraft for landing. Just after passing the first traffic there was a second cessna sighted at the OM, and then we started to see the others in the pattern. None of the other aircraft had landing lights on. Due to our high speed, the closure rate was probably close to 300 KTS with the cessna heading towards us. I don't think he realized that we would cover the 10 mi in less than 2 mins. This whole incident took place within 3 mins. We should have slowed down to approach speed with the amount of traffic in the area to give us more time to see the others. I should have waited to start down until after we cleared the cessna traffic instead of following the GS. We also had all exterior lights on and we should have been very visible. I strongly think that if they had the landing lights on we may have seen them sooner. Without TCASII, we would have been much closer or even impacted with the cessna. With two of them there, it cluttered the TCASII so we could not see clearly what was going on. This airport is extremely busy during summer daylight hours with a mix of airline turboprops and numerous training aircraft and could definitely benefit from a control tower that operated during these peak use periods.

Related reports:

Google
 

Original NASA ASRS Text

Title: ACR SF340A FLC EXECUTE EVASIVE ACTIONS DUE TO NMAC WITH C172 WHILE ON STRAIGHT-IN APCH TO STC ARPT. FO ADMITS TO FAST APCH SPD WITHIN 20 MI OF A BUSY, NON TWR CTL ARPT.

Narrative: I WAS THE FO ON A SAAB 340A FROM MSP TO STC AND WAS THE PF. AFTER DEP FROM MSP WE WERE CLRED DIRECT TO STC AT 4000 FT MSL BY MSP. WE WERE ALIGNED WITH THE EXTENDED LOC COURSE, SO I STARTED TRACKING THE LOC FOR THE ILS RWY 31 AT APPROX 30 NM OUT. WE COULD SEE PROMINENT STC LANDMARKS FROM 30 NM OUT. AT APPROX 20 NM OUT OF STC, ATC CLRED US FOR THE VISUAL APCH TO RWY 31 AND ADVISED US OF NUMEROUS TARGETS IN THE VICINITY OF STC. WE HAD THE TCASII SET TO THE 20 NM RANGE AND COULD SEE SEVERAL TARGETS IN THE AREA AT VARIOUS ALTS. THE CAPT WAS XMITTING OUR INTENTIONS ON CTAF AND WE HEARD AT LEAST ONE ACFT SAY HE WAS HOLDING AT THE OM. AT THIS TIME WE WERE INDICATING 240 KIAS AND AT 4000 FT. THE CTAF FREQ WAS BUSY WITH STC TFC CALLS. THE CAPT ASKED THE ACFT AT THE OM WHAT HIS INTENTIONS WERE: HIS REPLY WAS TO THE EFFECT THAT HE WOULD CONTINUE HOLDING. AT APPROX 10 NM FROM THE OM, THE CAPT DECIDED TO CANCEL IFR. I TURNED THE AUTOPLT OFF AND WAS FLYING. BY NOW THE TCASII WAS DISPLAYING MULTIPLE TARGETS CLOSE IN AND SO CLOSE TO EACH OTHER, IT WAS HARD TO PICK OUT AT WHAT ALT THEY WERE AT. WE WERE FLYING INTO THE SUN. AT APPROX 5 NM FROM THE OM, WE GOT A TA FOR THE ACFT OFF OUR L AND BELOW US. THE CAPT SAID TO LEVEL OFF UNTIL WE SEE THE TFC. WHILE THE TA OCCURRED, THE CAPT WAS ASKING THE CESSNA TFC WHAT HE WAS GOING TO DO, WHICH HE RESPONDED HE WOULD CLB TO GET OUT OF OUR WAY. THE CAPT TOLD THE CESSNA TO TURN S, AWAY FROM US AND NOT TO CLB AS WE WERE ABOVE HIM. IMMEDIATELY FOLLOWING HIS XMISSION, WE GOT THE RA 'CLB.' I WAS LOOKING OUTSIDE AND PITCHED UP TO 10 DEGS AND ADDED PWR. SOON AFTER, I PITCHED TO 20 DEGS UP AND CHKED MY PWR AT 100%. I SEE THE C172 PASS UNDER THE L SIDE SLIGHTLY BELOW US AND -300 FT SHOWED ON THE TCASII, ABOUT 1/4 MI, IF THAT. AFTER SIGHTING THE TFC I REDUCED PWR AND LEVELED OFF. WE CONFIGURED THE ACFT FOR LNDG. JUST AFTER PASSING THE FIRST TFC THERE WAS A SECOND CESSNA SIGHTED AT THE OM, AND THEN WE STARTED TO SEE THE OTHERS IN THE PATTERN. NONE OF THE OTHER ACFT HAD LNDG LIGHTS ON. DUE TO OUR HIGH SPD, THE CLOSURE RATE WAS PROBABLY CLOSE TO 300 KTS WITH THE CESSNA HEADING TOWARDS US. I DON'T THINK HE REALIZED THAT WE WOULD COVER THE 10 MI IN LESS THAN 2 MINS. THIS WHOLE INCIDENT TOOK PLACE WITHIN 3 MINS. WE SHOULD HAVE SLOWED DOWN TO APCH SPD WITH THE AMOUNT OF TFC IN THE AREA TO GIVE US MORE TIME TO SEE THE OTHERS. I SHOULD HAVE WAITED TO START DOWN UNTIL AFTER WE CLRED THE CESSNA TFC INSTEAD OF FOLLOWING THE GS. WE ALSO HAD ALL EXTERIOR LIGHTS ON AND WE SHOULD HAVE BEEN VERY VISIBLE. I STRONGLY THINK THAT IF THEY HAD THE LNDG LIGHTS ON WE MAY HAVE SEEN THEM SOONER. WITHOUT TCASII, WE WOULD HAVE BEEN MUCH CLOSER OR EVEN IMPACTED WITH THE CESSNA. WITH TWO OF THEM THERE, IT CLUTTERED THE TCASII SO WE COULD NOT SEE CLRLY WHAT WAS GOING ON. THIS ARPT IS EXTREMELY BUSY DURING SUMMER DAYLIGHT HRS WITH A MIX OF AIRLINE TURBOPROPS AND NUMEROUS TRAINING ACFT AND COULD DEFINITELY BENEFIT FROM A CTL TWR THAT OPERATED DURING THESE PEAK USE PERIODS.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.