Narrative:

Vicinity of hesperia airport, lake silverwood, cajon pass, ca. My aircraft, small aircraft X, 10 mi south of apple valley airport. I saw a descending mlt Y at my 3 O'clock position heading +/-170 degree. Mlt Y flew over hesperia area and lake silverwood, 800' AGL. Mlt Y made a steep right (westerly) turn, proceeding very close to the northern slope of san bernardino mountains, entering cajon pass at or about 5000', announcing on ont approach frequency 127.25, who quickly turned them over to norton tower frequency. I did not hear the mlt Y previously on edwards approach. I listened because I thought the aircraft was in trouble, descending at that altitude toward the mountains. My question: does this military mlt have on-board radar to detect small aircraft. I know it is my responsibility to see other VFR aircraft, but had I been flying through the pass in a northeast direction, a frequent procedure, at that approximately altitude, I would have been nose-to-nose with this mlt Y a fast, heavy jet, with no forewarning from ontario approach, who had no radar contact with the military cargo plane until nearly through the pass. I talked to ontario approach at the time, asking about the mlt Y. The controller seemed surprised at the low altitude of the plane, as was I surprised. I registered my inquiry with norton AFB, public affairs. Their response who to quote me the 500' AGL rule in VFR, which I of course already knew.

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Original NASA ASRS Text

Title: PLT OF LIGHT ACFT QUERIES USE OF MOUNTAIN PASS BY LOW FLYING MILITARY TRANSPORT, THE MOUNTAIN PASS IS FREQUENTLY USED BY SMALL ACFT.

Narrative: VICINITY OF HESPERIA ARPT, LAKE SILVERWOOD, CAJON PASS, CA. MY ACFT, SMA X, 10 MI S OF APPLE VALLEY ARPT. I SAW A DESCENDING MLT Y AT MY 3 O'CLOCK POSITION HDG +/-170 DEG. MLT Y FLEW OVER HESPERIA AREA AND LAKE SILVERWOOD, 800' AGL. MLT Y MADE A STEEP RIGHT (WESTERLY) TURN, PROCEEDING VERY CLOSE TO THE NORTHERN SLOPE OF SAN BERNARDINO MOUNTAINS, ENTERING CAJON PASS AT OR ABOUT 5000', ANNOUNCING ON ONT APCH FREQ 127.25, WHO QUICKLY TURNED THEM OVER TO NORTON TWR FREQ. I DID NOT HEAR THE MLT Y PREVIOUSLY ON EDWARDS APCH. I LISTENED BECAUSE I THOUGHT THE ACFT WAS IN TROUBLE, DESCENDING AT THAT ALT TOWARD THE MOUNTAINS. MY QUESTION: DOES THIS MIL MLT HAVE ON-BOARD RADAR TO DETECT SMALL ACFT. I KNOW IT IS MY RESPONSIBILITY TO SEE OTHER VFR ACFT, BUT HAD I BEEN FLYING THROUGH THE PASS IN A NE DIRECTION, A FREQUENT PROC, AT THAT APPROX ALT, I WOULD HAVE BEEN NOSE-TO-NOSE WITH THIS MLT Y A FAST, HEAVY JET, WITH NO FOREWARNING FROM ONTARIO APCH, WHO HAD NO RADAR CONTACT WITH THE MIL CARGO PLANE UNTIL NEARLY THROUGH THE PASS. I TALKED TO ONTARIO APCH AT THE TIME, ASKING ABOUT THE MLT Y. THE CTLR SEEMED SURPRISED AT THE LOW ALT OF THE PLANE, AS WAS I SURPRISED. I REGISTERED MY INQUIRY WITH NORTON AFB, PUBLIC AFFAIRS. THEIR RESPONSE WHO TO QUOTE ME THE 500' AGL RULE IN VFR, WHICH I OF COURSE ALREADY KNEW.

Data retrieved from NASA's ASRS site as of August 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.