Air carrier large transport altitude deviation excursion from clearance altitude in response to TCAS...

Attributes
ACN	171959
Time
Date	199102
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : swl
State Reference	MD
Altitude	msl bound lower : 29000 msl bound upper : 29600
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zdc
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	cruise other
Flight Plan	IFR
Aircraft 2
Operator	other
Make Model Name	Military Transport
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp pilot : flight engineer
Experience	flight time last 90 days : 150 flight time total : 10200 flight time type : 3000
ASRS Report	171959
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
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	flight crew : returned to intended course or assigned course flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 10000 unspecified : 600
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	other

Narrative:

Our aircraft departed FL290 to approximately FL296 due to a TCAS ii RA. RA was a result of an mlt approaching head-on at FL280. The mlt was doing a porpoise type maneuver. TCAS ii and ATC radar hits confirmed that mlt was at FL278 and began a climbing type maneuver to FL282. This at range of 6-8 mi from our aircraft. Cause of the mlt flight pattern is not known at this time. Our aircraft returned to FL290 west/O further incident.

Original NASA ASRS Text

Title: ACR LGT ALT DEVIATION EXCURSION FROM CLRNC ALT IN RESPONSE TO TCAS II RA.

Narrative: OUR ACFT DEPARTED FL290 TO APPROX FL296 DUE TO A TCAS II RA. RA WAS A RESULT OF AN MLT APCHING HEAD-ON AT FL280. THE MLT WAS DOING A PORPOISE TYPE MANEUVER. TCAS II AND ATC RADAR HITS CONFIRMED THAT MLT WAS AT FL278 AND BEGAN A CLBING TYPE MANEUVER TO FL282. THIS AT RANGE OF 6-8 MI FROM OUR ACFT. CAUSE OF THE MLT FLT PATTERN IS NOT KNOWN AT THIS TIME. OUR ACFT RETURNED TO FL290 W/O FURTHER INCIDENT.

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.

Air carrier large transport altitude deviation excursion from clearance altitude in response to TCAS ii RA.