Citationjet (C525/C526) - CJ I / II / III / IV
Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Flight Crew Last 90 Days 60; Flight Crew Total 7000; Flight Crew Type 1500
Situational Awareness
Conflict NMAC; Deviation - Altitude Undershoot; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance
Flight Crew Took Evasive Action; Flight Crew Became Reoriented
Human Factors
On the approach to MTN talking to Potomac Approach; I received ATIS information and Runway 15 in use. Potomac Approach asked if we could accept Runway 33 and we acknowledged that we could. The controller was also in contact with a military aircraft approximately 5 miles in trail for the same airport and advised us to keep our speed up and cleared us direct to the airport. Approximately 7 miles south of the field; we called the field in sight and we were cleared for the visual approach to Runway 33 and contact the Tower. No frequency was given so I had to look it up quickly. The PIC acknowledged he had the airport; but did not commence a descent right away and we were level at 3;000 feet and 200 KTS. As I was looking up the tower frequency heads down; 'traffic' alert sound from the TCAS. I glanced up to the MFD and saw a target 11 o'clock same altitude; moments later we had an RA alert to descend. The PIC flying did not respond to the RA command and I pushed the yoke to commence an immediate descent. The [military aircraft] passed over us between 200-300 feet. I contacted the Tower and realized the PIC had overflown the final approach course. We requested Runway 15 and entered a downwind for; but was requested if we could still land runway 33 due to military requirements. We made a 180 and entered a right base for Runway 33 and landed with no further incident.
CJ-3 First Officer reported an NMAC on approach to MTN when the flying pilot failed to descend on the glide slope as cleared.