Altitude deviation altitude excursion in pilot flight crew response to TCASII RA. Near midair collision turned into potential conflict by aircraft maneuver.

Home

Browse by month

Random

Latest

About

Contact

Attributes
ACN	217341
Time
Date	199208
Day	Mon
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : pmm airport : ord
State Reference	IL
Altitude	msl bound lower : 10000 msl bound upper : 10700
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zau
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	descent other
Route In Use	enroute : direct
Flight Plan	IFR
Aircraft 2
Make Model Name	Small Aircraft, Low Wing, 1 Eng, Retractable Gear
Flight Phase	cruise other
Flight Plan	VFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 180 flight time total : 3500 flight time type : 180
ASRS Report	217341
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : flight engineer pilot : atp pilot : cfi
Experience	flight time last 90 days : 180 flight time total : 12000 flight time type : 500
ASRS Report	217326
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : airborne less severe non adherence : far non adherence : required legal separation other anomaly other other spatial deviation
Independent Detector	aircraft equipment other aircraft equipment : unspecified other controllera
Resolutory Action	flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 0 vertical : 900
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	Pilot Deviation other
Situations
ATC Facility	procedure or policy : unspecified

Narrative:

While descending for an approach/landing at O'hare airport TCASII gave a traffic warning (9700 ft) with our aircraft was passing 10000 ft. Neither pilot had traffic in sight. ATC had not called any traffic to our attention. TCASII issued an 'RA' warning and a climb was immediately initiated to 10700 ft and the captain observed a light single engine aircraft pass direction under our aircraft moving right to left. When small aircraft was clear, we advised chicago center and continued our descent to landing. Supplemental information from acn 217326. TA turned to RA and we were still unable to pick up the traffic visually, even with the help of TCASII position. When the RA warning sounded since we did not have the traffic we complied with the warning instructions. We climbed to 10700 ft in accordance with air carrier procedures.

Original NASA ASRS Text

Title: ALTDEV ALT EXCURSION IN PLT FLC RESPONSE TO TCASII RA. NMAC TURNED INTO POTENTIAL CONFLICT BY ACFT MANEUVER.

Narrative: WHILE DSNDING FOR AN APCH/LNDG AT O'HARE ARPT TCASII GAVE A TFC WARNING (9700 FT) WITH OUR ACFT WAS PASSING 10000 FT. NEITHER PLT HAD TFC IN SIGHT. ATC HAD NOT CALLED ANY TFC TO OUR ATTN. TCASII ISSUED AN 'RA' WARNING AND A CLB WAS IMMEDIATELY INITIATED TO 10700 FT AND THE CAPT OBSERVED A LIGHT SINGLE ENG ACFT PASS DIRECTION UNDER OUR ACFT MOVING R TO L. WHEN SMA WAS CLR, WE ADVISED CHICAGO CTR AND CONTINUED OUR DSCNT TO LNDG. SUPPLEMENTAL INFO FROM ACN 217326. TA TURNED TO RA AND WE WERE STILL UNABLE TO PICK UP THE TFC VISUALLY, EVEN WITH THE HELP OF TCASII POS. WHEN THE RA WARNING SOUNDED SINCE WE DID NOT HAVE THE TFC WE COMPLIED WITH THE WARNING INSTRUCTIONS. WE CLBED TO 10700 FT IAW ACR PROCS.

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.