Narrative:

Air carrier flight from ric-dca was cleared for the visual runway 15 at dca. Tower asked if we had 727 traffic in sight that was doing runway 18 river visual. Traffic was acknowledged. Tower asked if airport was in sight. Airport was acknowledged. Runway 15 was also in sight and we were cleared for the visual approach to runway 15. Approximately 3-4 mi from runway 15, tower then cleared us for the river visual to runway 18. My captain asked to confirm this and it was confirmed by tower. We now were within 2 mi of the 727 traffic we were to follow. We slowed our aircraft and broke off the approach to runway 15 and squared off the right base for runway 18 to allow separation with the 727 traffic. We were keeping watch over the river not to stray into the P-56 area. Tower advised us we were straying into P-56 and asked us to make a hard left turn and we were given vectors for the runway 21 visual. The hard left turn tower advised seemed to put us into the P-56. We continued flying tower assigned vectors and landed on runway 21 without any further incident. At no time did we appear to place other aircraft in danger. The WX was 2500 scattered, 6500 broken with 10 mi visibility and light rain showers but at our altitude it was less.

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Original NASA ASRS Text

Title: FLC OF AN LTT ACR ACFT INADVERTENTLY ENTERED A PROHIBITED AREA AS A RESULT OF ATTEMPTING TO ADJUST THEIR SPACING BEHIND ANOTHER ACFT ON A VISUAL APCH.

Narrative: ACR FLT FROM RIC-DCA WAS CLRED FOR THE VISUAL RWY 15 AT DCA. TWR ASKED IF WE HAD 727 TFC IN SIGHT THAT WAS DOING RWY 18 RIVER VISUAL. TFC WAS ACKNOWLEDGED. TWR ASKED IF ARPT WAS IN SIGHT. ARPT WAS ACKNOWLEDGED. RWY 15 WAS ALSO IN SIGHT AND WE WERE CLRED FOR THE VISUAL APCH TO RWY 15. APPROX 3-4 MI FROM RWY 15, TWR THEN CLRED US FOR THE RIVER VISUAL TO RWY 18. MY CAPT ASKED TO CONFIRM THIS AND IT WAS CONFIRMED BY TWR. WE NOW WERE WITHIN 2 MI OF THE 727 TFC WE WERE TO FOLLOW. WE SLOWED OUR ACFT AND BROKE OFF THE APCH TO RWY 15 AND SQUARED OFF THE R BASE FOR RWY 18 TO ALLOW SEPARATION WITH THE 727 TFC. WE WERE KEEPING WATCH OVER THE RIVER NOT TO STRAY INTO THE P-56 AREA. TWR ADVISED US WE WERE STRAYING INTO P-56 AND ASKED US TO MAKE A HARD L TURN AND WE WERE GIVEN VECTORS FOR THE RWY 21 VISUAL. THE HARD L TURN TWR ADVISED SEEMED TO PUT US INTO THE P-56. WE CONTINUED FLYING TWR ASSIGNED VECTORS AND LANDED ON RWY 21 WITHOUT ANY FURTHER INCIDENT. AT NO TIME DID WE APPEAR TO PLACE OTHER ACFT IN DANGER. THE WX WAS 2500 SCATTERED, 6500 BROKEN WITH 10 MI VISIBILITY AND LIGHT RAIN SHOWERS BUT AT OUR ALT IT WAS LESS.

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.