Pilot of small aircraft twin deviated from heading in dca TCA.

Attributes
ACN	185644
Time
Date	199108
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : aml
State Reference	VA
Altitude	msl bound lower : 2000 msl bound upper : 4000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : iad
Operator	general aviation : personal
Make Model Name	Small Transport, Low Wing, 2 Recip Eng
Flight Phase	cruise other cruise other descent other
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : commercial
Experience	flight time last 90 days : 15 flight time total : 460 flight time type : 200
ASRS Report	185644
Person 2
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Events
Anomaly	non adherence : clearance other spatial deviation
Independent Detector	other other : unspecified cockpit
Resolutory Action	flight crew : took evasive action flight crew : became reoriented
Consequence	Other
Miss Distance	horizontal : 1000 vertical : 0
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I was flying sbound between washington dulles and washington national airports. I contacted dulles approach a few mi south of the potomac river. I was at 4000 ft and was instructed to descend to 2000 ft. At that point I noticed traffic at about 11 O'clock and a mi and a half. My attention must have been devoted entirely to the traffic for a moment, because when I glanced again at the HSI, my heading had slipped to 230. I started a steep left turn, when the controller inquired 'when did I give you a turn to the west?' I did not respond, save to say that I had traffic in sight (which I had). I believe that the traffic problem is the existence of the washington TCA. Before its initiation manassas airport VFR traffic could overfly the iad arsa, reducing the possible collision paths. That is no longer a viable navigational alternative. All traffic is forced to circumnav the TCA or is forced into the 'VFR corridor' that I was flying.

Original NASA ASRS Text

Title: PLT OF SMA TWIN DEVIATED FROM HDG IN DCA TCA.

Narrative: I WAS FLYING SBOUND BTWN WASHINGTON DULLES AND WASHINGTON NATL ARPTS. I CONTACTED DULLES APCH A FEW MI S OF THE POTOMAC RIVER. I WAS AT 4000 FT AND WAS INSTRUCTED TO DSND TO 2000 FT. AT THAT POINT I NOTICED TFC AT ABOUT 11 O'CLOCK AND A MI AND A HALF. MY ATTN MUST HAVE BEEN DEVOTED ENTIRELY TO THE TFC FOR A MOMENT, BECAUSE WHEN I GLANCED AGAIN AT THE HSI, MY HDG HAD SLIPPED TO 230. I STARTED A STEEP L TURN, WHEN THE CTLR INQUIRED 'WHEN DID I GIVE YOU A TURN TO THE W?' I DID NOT RESPOND, SAVE TO SAY THAT I HAD TFC IN SIGHT (WHICH I HAD). I BELIEVE THAT THE TFC PROBLEM IS THE EXISTENCE OF THE WASHINGTON TCA. BEFORE ITS INITIATION MANASSAS ARPT VFR TFC COULD OVERFLY THE IAD ARSA, REDUCING THE POSSIBLE COLLISION PATHS. THAT IS NO LONGER A VIABLE NAVIGATIONAL ALTERNATIVE. ALL TFC IS FORCED TO CIRCUMNAV THE TCA OR IS FORCED INTO THE 'VFR CORRIDOR' THAT I WAS FLYING.

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.