GA flight instructor reported a near midair collision while on a practice instrument approach to run...

Narrative:

I was providing instrument instruction to a cfii candidate. The student was wearing a view limiting device. We were conducting practice instrument approaches to jnx runways 3 and 21. We were currently on the practice ILS approach to runway 3 at jnx at the time of the intentions.I made an announcement on the CTAF frequency that we were 7 miles out on the practice ILS runway 3 circle to land on 21. We heard another aircraft make an announcement that they were 3 miles away and entering the downwind for runway 21 on a 45 degree entry. The tone of the pilot's voice made me suspect it was a student pilot on a solo flight. The next announcement I made was a 5 mile final for the ILS runway 3 circle to land on 21. The other airplane in the pattern then made an announcement that they were going to join the crosswind for runway 3. I queried the airplane and asked if the pilot was by themselves and got no response. At this time I made the decision to continue the approach to a full stop instead of executing a circling approach. I made an announcement that we were on a 1.5 mile final and that we would be a full stop; at this time I observed the previous mentioned aircraft turn the base leg in front of us. My student was still wearing his view limiting device; I took control of the airplane and executed a missed approach sidestepping to the right of the runway and announcing my intentions on the CTAF too. We rejoined the traffic pattern on the upwind and made a normal approach to landing.

Original NASA ASRS Text

Title: GA flight instructor reported a NMAC while on a practice instrument approach to Runway 3 at JNX when another GA aircraft turned base in front of them.

Narrative: I was providing instrument instruction to a CFII candidate. The student was wearing a view limiting device. We were conducting practice instrument approaches to JNX runways 3 and 21. We were currently on the practice ILS approach to runway 3 at JNX at the time of the intentions.I made an announcement on the CTAF frequency that we were 7 miles out on the practice ILS runway 3 circle to land on 21. We heard another aircraft make an announcement that they were 3 miles away and entering the downwind for runway 21 on a 45 degree entry. The tone of the pilot's voice made me suspect it was a student pilot on a solo flight. The next announcement I made was a 5 mile final for the ILS runway 3 circle to land on 21. The other airplane in the pattern then made an announcement that they were going to join the crosswind for runway 3. I queried the airplane and asked if the pilot was by themselves and got no response. At this time I made the decision to continue the approach to a full stop instead of executing a circling approach. I made an announcement that we were on a 1.5 mile final and that we would be a full stop; at this time I observed the previous mentioned aircraft turn the base leg in front of us. My student was still wearing his view limiting device; I took control of the airplane and executed a missed approach sidestepping to the right of the runway and announcing my intentions on the CTAF too. We rejoined the traffic pattern on the upwind and made a normal approach to landing.

Data retrieved from NASA's ASRS site 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.

Attributes
ACN	1455735
Time
Date	201706
Local Time Of Day	1201-1800
Place
Locale Reference	JNX.Airport
State Reference	NC
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Small Aircraft Low Wing 1 Eng Fixed Gear
Operating Under FAR Part	Part 91
Flight Phase	Final Approach
Flight Plan	None
Aircraft 2
Make Model Name	Small Aircraft Low Wing 1 Eng Fixed Gear
Operating Under FAR Part	Part 91
Flight Phase	Final Approach
Person 1
Function	Pilot Not Flying Instructor
Qualification	Flight Crew Multiengine Flight Crew Instrument Flight Crew Flight Instructor Flight Crew Commercial
Experience	Flight Crew Last 90 Days 220 Flight Crew Total 750 Flight Crew Type 276
Events
Anomaly	Conflict NMAC Deviation - Procedural Published Material / Policy
Miss Distance	Horizontal 500 Vertical 0

GA flight instructor reported a near midair collision while on a practice instrument approach to runway 3 at jnx when another GA aircraft turned base in front of them.