Air carrier medium large transport reversed descent in response to TCASII RA.

Attributes
ACN	175557
Time
Date	199104
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : omn
State Reference	FL
Altitude	msl bound lower : 16500 msl bound upper : 16500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zjx
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	descent other
Route In Use	enroute airway : zjx
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	cruise other
Flight Plan	VFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : commercial pilot : instrument
Experience	flight time last 90 days : 150 flight time total : 25000 flight time type : 10000
ASRS Report	175557
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Events
Anomaly	conflict : airborne less severe
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	flight crew : returned to intended course or assigned course
Consequence	Other
Miss Distance	vertical : 500
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	other

Narrative:

Air carrier flight en route mco. Flight cleared to descend to 12000' by ZJX. When out of 16500', TCASII TA was heard, followed soon after by RA by TCASII, indicating a climb command of 1500 FPM. Aircraft was flown as commanded by TCASII until conflict was resolved when descent to 12000' was resumed. ATC was advised of conflict and indicated they were aware of VFR aircraft, but due to workload at the time were unable to issue a timely warning. The entire issue of this type of conflict could be eliminated if ATC would discontinue issuing clrncs through known VFR occupied altitude. This practice has resulted in the largest # of personal near misses in my 36 yrs of flying.

Original NASA ASRS Text

Title: ACR MLG REVERSED DESCENT IN RESPONSE TO TCASII RA.

Narrative: ACR FLT ENRTE MCO. FLT CLRED TO DSND TO 12000' BY ZJX. WHEN OUT OF 16500', TCASII TA WAS HEARD, FOLLOWED SOON AFTER BY RA BY TCASII, INDICATING A CLB COMMAND OF 1500 FPM. ACFT WAS FLOWN AS COMMANDED BY TCASII UNTIL CONFLICT WAS RESOLVED WHEN DSNT TO 12000' WAS RESUMED. ATC WAS ADVISED OF CONFLICT AND INDICATED THEY WERE AWARE OF VFR ACFT, BUT DUE TO WORKLOAD AT THE TIME WERE UNABLE TO ISSUE A TIMELY WARNING. THE ENTIRE ISSUE OF THIS TYPE OF CONFLICT COULD BE ELIMINATED IF ATC WOULD DISCONTINUE ISSUING CLRNCS THROUGH KNOWN VFR OCCUPIED ALT. THIS PRACTICE HAS RESULTED IN THE LARGEST # OF PERSONAL NEAR MISSES IN MY 36 YRS OF 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.