Narrative:

I had followed all ADIZ procedures by filing an ADIZ flight plan, receiving transponder code from potomac clearance, contacting potomac departure after departure from jyo at about 1200 ft MSL. Potomac departure advised me to set transponder to my assigned code. At that time, I noticed the transponder was still on standby, instead of altitude mode. I immediately turned it to altitude mode and potomac advised of radar contact. About 15 mins later on the return to jyo, the controller said the supervisor was asking why they only had a 'primary' target for me on the departure. I provided the reason, and a few mins later he provided a phone number to call upon landing. I called the phone number upon landing. I explained what happened. He said he would investigate the event and discuss with the controller to determine if this was a pilot deviation. If it is determined to be a deviation, I would hear from the FSDO. I was instructing a student who had never flown at night and was not familiar with the aircraft, nor the jyo airspace. Due to the instructing, I wasn't able to call for a transponder code until after the student completed the before takeoff checklist, which includes the transponder to altitude mode. When I received the code, I was distraction by the student and never turned the transponder from standby to altitude mode.

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Original NASA ASRS Text

Title: FLT INSTRUCTOR AND STUDENT PLT DO EVERYTHING RIGHT IN THE DC ADIZ BUT FORGET TO SQUAWK ALT MODE ON XPONDER. GOT CAUGHT.

Narrative: I HAD FOLLOWED ALL ADIZ PROCS BY FILING AN ADIZ FLT PLAN, RECEIVING XPONDER CODE FROM POTOMAC CLRNC, CONTACTING POTOMAC DEP AFTER DEP FROM JYO AT ABOUT 1200 FT MSL. POTOMAC DEP ADVISED ME TO SET XPONDER TO MY ASSIGNED CODE. AT THAT TIME, I NOTICED THE XPONDER WAS STILL ON STANDBY, INSTEAD OF ALT MODE. I IMMEDIATELY TURNED IT TO ALT MODE AND POTOMAC ADVISED OF RADAR CONTACT. ABOUT 15 MINS LATER ON THE RETURN TO JYO, THE CTLR SAID THE SUPVR WAS ASKING WHY THEY ONLY HAD A 'PRIMARY' TARGET FOR ME ON THE DEP. I PROVIDED THE REASON, AND A FEW MINS LATER HE PROVIDED A PHONE NUMBER TO CALL UPON LNDG. I CALLED THE PHONE NUMBER UPON LNDG. I EXPLAINED WHAT HAPPENED. HE SAID HE WOULD INVESTIGATE THE EVENT AND DISCUSS WITH THE CTLR TO DETERMINE IF THIS WAS A PLTDEV. IF IT IS DETERMINED TO BE A DEV, I WOULD HEAR FROM THE FSDO. I WAS INSTRUCTING A STUDENT WHO HAD NEVER FLOWN AT NIGHT AND WAS NOT FAMILIAR WITH THE ACFT, NOR THE JYO AIRSPACE. DUE TO THE INSTRUCTING, I WASN'T ABLE TO CALL FOR A XPONDER CODE UNTIL AFTER THE STUDENT COMPLETED THE BEFORE TKOF CHKLIST, WHICH INCLUDES THE XPONDER TO ALT MODE. WHEN I RECEIVED THE CODE, I WAS DISTR BY THE STUDENT AND NEVER TURNED THE XPONDER FROM STANDBY TO ALT MODE.

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.