Narrative:

I was the instructor on a flight with a pilot who had not flown instruments in a couple of years. We departed ZZZ airport to go to ZZZ1 airport to practice some approachs. We did the GPS followed by the published missed approach. We did a few laps in holding then decided to do the ILS approach. While we were heading outbound, the student kept drifting further to the northwest. After he completed his procedure turn, he was so far off course that we were heading for the prohibited airspace ZZZ2. After a couple of mins I realized that the student didn't know where he was or that we were heading for ZZZ2 prohibited airspace. So I told him to turn and try to get back on course. A couple of military aircraft came up next to us for a short time and then flew off. At this time we flew back to ZZZ. After we landed I found out that ZZZ2 prohibited airspace had been extended 8 mi, so we had mistakenly entered the prohibited airspace.

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Original NASA ASRS Text

Title: A GA TRAINING FLT STRAYS OFF COURSE DURING AN ATTEMPTED ILS PROC TURN AND IS INTERCEPTED BY TWO MIL ACFT IN PROX OF A POWER PLANT LISTED IN THE PUBLISHED TFR NEAR ZZZ, US.

Narrative: I WAS THE INSTRUCTOR ON A FLT WITH A PLT WHO HAD NOT FLOWN INSTRUMENTS IN A COUPLE OF YEARS. WE DEPARTED ZZZ ARPT TO GO TO ZZZ1 ARPT TO PRACTICE SOME APCHS. WE DID THE GPS FOLLOWED BY THE PUBLISHED MISSED APCH. WE DID A FEW LAPS IN HOLDING THEN DECIDED TO DO THE ILS APCH. WHILE WE WERE HDG OUTBOUND, THE STUDENT KEPT DRIFTING FURTHER TO THE NW. AFTER HE COMPLETED HIS PROC TURN, HE WAS SO FAR OFF COURSE THAT WE WERE HDG FOR THE PROHIBITED AIRSPACE ZZZ2. AFTER A COUPLE OF MINS I REALIZED THAT THE STUDENT DIDN'T KNOW WHERE HE WAS OR THAT WE WERE HDG FOR ZZZ2 PROHIBITED AIRSPACE. SO I TOLD HIM TO TURN AND TRY TO GET BACK ON COURSE. A COUPLE OF MIL ACFT CAME UP NEXT TO US FOR A SHORT TIME AND THEN FLEW OFF. AT THIS TIME WE FLEW BACK TO ZZZ. AFTER WE LANDED I FOUND OUT THAT ZZZ2 PROHIBITED AIRSPACE HAD BEEN EXTENDED 8 MI, SO WE HAD MISTAKENLY ENTERED THE PROHIBITED AIRSPACE.

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.