Narrative:

I had as a passenger on this trip an elderly gentleman who is suffering from alzheimer's disease. He does love to go flying with me but because he is somewhat unpredictable, I normally put him in the back seat. This day I planned to show him a friend's house which was in heavily wooded and somewhat mountainous terrain. I have been to this place several times via automatic and the number of houses and other buildings that I passed were so few that I considered this as 'other than congested area.' navigation was by GPS which took me directly to his place, and the minimum altitudes specified in far 91.119 (C) were adhered to. We made 1 circle above the general area, and then departed the same direction from which we came. During the circle I noticed a short distance beyond my friends house on the road that I normally traveled was a cluster of several houses in a somewhat more cleared area. Probably a development of some sort. Since this could possibly be considered a 'settlement' and therefore become a 'congested area,' then of course higher minimum altitudes would be required. At one time I would regard everything on the sectional chart that was not in yellow as uncongested area, but it occurs to me that this may not be correct. I plan to be at a flight instructor clinic later this month and it will be a topic I hope to bring up. Although this flight was entirely outside of the class B airspace surrounding iad, it was within the 30 mi mode C ring. When I was securing the avionics at the conclusion of this flight, the transponder was already turned off. How it got that way I can only guess, but my passenger definitely goes in the back seat next time.

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Original NASA ASRS Text

Title: LOW ALT CIVIL FLT WITHOUT XPONDER TURNED ON UNDER TCA BY PLT OF SMA CESSNA.

Narrative: I HAD AS A PAX ON THIS TRIP AN ELDERLY GENTLEMAN WHO IS SUFFERING FROM ALZHEIMER'S DISEASE. HE DOES LOVE TO GO FLYING WITH ME BUT BECAUSE HE IS SOMEWHAT UNPREDICTABLE, I NORMALLY PUT HIM IN THE BACK SEAT. THIS DAY I PLANNED TO SHOW HIM A FRIEND'S HOUSE WHICH WAS IN HEAVILY WOODED AND SOMEWHAT MOUNTAINOUS TERRAIN. I HAVE BEEN TO THIS PLACE SEVERAL TIMES VIA AUTO AND THE NUMBER OF HOUSES AND OTHER BUILDINGS THAT I PASSED WERE SO FEW THAT I CONSIDERED THIS AS 'OTHER THAN CONGESTED AREA.' NAV WAS BY GPS WHICH TOOK ME DIRECTLY TO HIS PLACE, AND THE MINIMUM ALTS SPECIFIED IN FAR 91.119 (C) WERE ADHERED TO. WE MADE 1 CIRCLE ABOVE THE GENERAL AREA, AND THEN DEPARTED THE SAME DIRECTION FROM WHICH WE CAME. DURING THE CIRCLE I NOTICED A SHORT DISTANCE BEYOND MY FRIENDS HOUSE ON THE ROAD THAT I NORMALLY TRAVELED WAS A CLUSTER OF SEVERAL HOUSES IN A SOMEWHAT MORE CLRED AREA. PROBABLY A DEVELOPMENT OF SOME SORT. SINCE THIS COULD POSSIBLY BE CONSIDERED A 'SETTLEMENT' AND THEREFORE BECOME A 'CONGESTED AREA,' THEN OF COURSE HIGHER MINIMUM ALTS WOULD BE REQUIRED. AT ONE TIME I WOULD REGARD EVERYTHING ON THE SECTIONAL CHART THAT WAS NOT IN YELLOW AS UNCONGESTED AREA, BUT IT OCCURS TO ME THAT THIS MAY NOT BE CORRECT. I PLAN TO BE AT A FLT INSTRUCTOR CLINIC LATER THIS MONTH AND IT WILL BE A TOPIC I HOPE TO BRING UP. ALTHOUGH THIS FLT WAS ENTIRELY OUTSIDE OF THE CLASS B AIRSPACE SURROUNDING IAD, IT WAS WITHIN THE 30 MI MODE C RING. WHEN I WAS SECURING THE AVIONICS AT THE CONCLUSION OF THIS FLT, THE XPONDER WAS ALREADY TURNED OFF. HOW IT GOT THAT WAY I CAN ONLY GUESS, BUT MY PAX DEFINITELY GOES IN THE BACK SEAT NEXT TIME.

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.