Altitude deviation altitude excursion due to TCASII RA with opposite direction same altitude traffic...

Attributes
ACN	252015
Time
Date	199309
Day	Wed
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : dca
State Reference	DC
Altitude	msl bound lower : 9600 msl bound upper : 10000
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	tracon : dca tracon : dtw
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	cruise other
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp pilot : cfi pilot : flight engineer
Experience	flight time last 90 days : 120 flight time total : 12230 flight time type : 300
ASRS Report	252015
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : airborne less severe non adherence : clearance other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 9000 vertical : 400
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

While level at 10000 ft MSL with no information from ATC of approaching traffic, the captain and I noticed an aircraft at our altitude on TCASII. Continued observation of aircraft on TCASII showed no change in altitude and aircraft fast becoming a conflict. This was confirmed by TCASII 3-4 seconds later with an RA and TCASII command to descend. The captain immediately descended to approximately 9600 ft MSL when we received a clear of conflict and climbed back to 10000 ft. ATC had very little information throughout this situation. The captain's performance was flawless and his quick reaction to this situation was impressive.

Original NASA ASRS Text

Title: ALTDEV ALT EXCURSION DUE TO TCASII RA WITH OPPOSITE DIRECTION SAME ALT TFC.

Narrative: WHILE LEVEL AT 10000 FT MSL WITH NO INFO FROM ATC OF APCHING TFC, THE CAPT AND I NOTICED AN ACFT AT OUR ALT ON TCASII. CONTINUED OBSERVATION OF ACFT ON TCASII SHOWED NO CHANGE IN ALT AND ACFT FAST BECOMING A CONFLICT. THIS WAS CONFIRMED BY TCASII 3-4 SECONDS LATER WITH AN RA AND TCASII COMMAND TO DSND. THE CAPT IMMEDIATELY DSNDED TO APPROX 9600 FT MSL WHEN WE RECEIVED A CLR OF CONFLICT AND CLBED BACK TO 10000 FT. ATC HAD VERY LITTLE INFO THROUGHOUT THIS SIT. THE CAPT'S PERFORMANCE WAS FLAWLESS AND HIS QUICK REACTION TO THIS SIT WAS IMPRESSIVE.

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.