Narrative:

I departed on an IFR flight to oxnard (oxr). My plane is equipped with GPS (/g) and ads-B. I was cleared by mugu approach to fly the ILS runway 25 approach into oxr and I was told to contact the oxr tower at the marker (pards). At pards; I was established on the glideslope and localizer. Upon reaching pards; I switched to the oxr tower frequency. Just as I switched to the oxr tower frequency but before I had transmitted to the tower; I suddenly saw a single-engine wwii fighter plane at my 1 o'clock position about 500 feet away. The plane was in a banked left turn crossing perpendicular to my path from my right to my left. It appeared to be at or slightly above my altitude. I immediately reduced power and shoved the control wheel forward to dive below the plane. The plane passed above me; but it happened so quickly that I really am not sure how close we came to colliding. I then transmitted to the oxr tower to report that I was with them on the ILS; and I told the tower controller that I had just almost had a mid-air collision with a wwii fighter. I do not remember the oxr tower controller's exact words; but he responded with something to the effect of; 'yeah; I was just about to call you to warn you that he was turning into you.' he then cleared me to land; and I landed at oxr without incident. I had no further conversation with the controller about the near-miss. Even though my plane is equipped with ads-B; I did not receive an aural or visual traffic alert because the [avionic] unit's 'pop-up traffic alerts' are disabled when an approach is active on the GPS. My plane has dual glideslopes and both were tuned to the oxr ILS 25; so I am certain that I was on the glideslope during the approach. My hypothesis is that the fighter was making a left overhead break over the camarillo (cma) airport to turn a left downwind for runway 26 at camarillo. However; if my hypothesis is correct; the fighter was about 800 feet above the cma pattern altitude of 877 MSL.

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Original NASA ASRS Text

Title: The pilot of a general aviation aircraft reported a NMAC with a warbird while on approach to OXR. The pilot received no prior warning from Approach and had not yet established contact with the Tower. The on-board collision avoidance system also did not provide advanced notice; but was likely due to the mode being disabled in approach mode.

Narrative: I departed on an IFR flight to Oxnard (OXR). My plane is equipped with GPS (/g) and ADS-B. I was cleared by Mugu approach to fly the ILS runway 25 approach into OXR and I was told to contact the OXR tower at the marker (PARDS). At PARDS; I was established on the glideslope and localizer. Upon reaching PARDS; I switched to the OXR tower frequency. Just as I switched to the OXR tower frequency but before I had transmitted to the tower; I suddenly saw a single-engine WWII fighter plane at my 1 o'clock position about 500 feet away. The plane was in a banked left turn crossing perpendicular to my path from my right to my left. It appeared to be at or slightly above my altitude. I immediately reduced power and shoved the control wheel forward to dive below the plane. The plane passed above me; but it happened so quickly that I really am not sure how close we came to colliding. I then transmitted to the OXR tower to report that I was with them on the ILS; and I told the tower controller that I had just almost had a mid-air collision with a WWII fighter. I do not remember the OXR tower controller's exact words; but he responded with something to the effect of; 'yeah; I was just about to call you to warn you that he was turning into you.' He then cleared me to land; and I landed at OXR without incident. I had no further conversation with the controller about the near-miss. Even though my plane is equipped with ADS-B; I did not receive an aural or visual traffic alert because the [avionic] unit's 'pop-up traffic alerts' are disabled when an approach is active on the GPS. My plane has dual glideslopes and both were tuned to the OXR ILS 25; so I am certain that I was on the glideslope during the approach. My hypothesis is that the fighter was making a left overhead break over the Camarillo (CMA) airport to turn a left downwind for runway 26 at Camarillo. However; if my hypothesis is correct; the fighter was about 800 feet above the CMA pattern altitude of 877 MSL.

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.