Aircraft was descended through an occupied altitude resulting in less than standard separation.

Attributes
ACN	139897
Time
Date	199003
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : cae
State Reference	SC
Altitude	msl bound lower : 5000 msl bound upper : 8000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : cae
Operator	general aviation : personal
Make Model Name	Small Aircraft, High Wing, 1 Eng, Fixed Gear
Flight Phase	cruise other
Route In Use	enroute airway : v53
Flight Plan	IFR
Aircraft 2
Operator	general aviation : personal
Make Model Name	Small Transport, Low Wing, 2 Recip Eng
Flight Phase	descent other
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Experience	controller military : 8 controller non radar : 11 controller radar : 2
ASRS Report	139897
Person 2
Affiliation	government : military
Function	controller : approach
Qualification	controller : radar
Events
Anomaly	non adherence : published procedure non adherence : required legal separation other anomaly other
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance
Consequence	Other
Miss Distance	horizontal : 2250 vertical : 200
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error Intra Facility Coordination Failure

Narrative:

An small aircraft X was sebnd on V-53, approximately 17 DME southeast, at 5000'. An small transport Y was nwbnd on V-53 at 8000' descending. Both aircraft were in columbia approach airspace. Small aircraft X had been handed off to the air force approach controller at shaw air force base. Small transport Y had been handed off to columbia approach. Our standard letter of agreement between us allows shaw approach to handoff aircraft descending to 4000'. In this instance shaw was late effecting communication transfer. Thus it was not determined that small transport Y was going to get too close to small aircraft X until sep was lost. Why shaw would descend an aircraft in the face of traffic they had already handed off is beyond me. In this instance I believe a procedure that is unsafe nearly caused a loss of life. In the future if aircraft were level at the appropriate altitude for direction of flight instead of descending we could avoid this hazardous situation. There was no time for evasive action to be taken on my part as it all occurred within the span of 30-45 seconds and I could not raise small transport Y on the radio nor turn small aircraft X in time.

Original NASA ASRS Text

Title: ACFT WAS DESCENDED THROUGH AN OCCUPIED ALT RESULTING IN LESS THAN STANDARD SEPARATION.

Narrative: AN SMA X WAS SEBND ON V-53, APPROX 17 DME SE, AT 5000'. AN SMT Y WAS NWBND ON V-53 AT 8000' DSNDING. BOTH ACFT WERE IN COLUMBIA APCH AIRSPACE. SMA X HAD BEEN HANDED OFF TO THE AIR FORCE APCH CTLR AT SHAW AIR FORCE BASE. SMT Y HAD BEEN HANDED OFF TO COLUMBIA APCH. OUR STANDARD LETTER OF AGREEMENT BTWN US ALLOWS SHAW APCH TO HDOF ACFT DSNDING TO 4000'. IN THIS INSTANCE SHAW WAS LATE EFFECTING COM TRANSFER. THUS IT WAS NOT DETERMINED THAT SMT Y WAS GOING TO GET TOO CLOSE TO SMA X UNTIL SEP WAS LOST. WHY SHAW WOULD DSND AN ACFT IN THE FACE OF TFC THEY HAD ALREADY HANDED OFF IS BEYOND ME. IN THIS INSTANCE I BELIEVE A PROC THAT IS UNSAFE NEARLY CAUSED A LOSS OF LIFE. IN THE FUTURE IF ACFT WERE LEVEL AT THE APPROPRIATE ALT FOR DIRECTION OF FLT INSTEAD OF DSNDING WE COULD AVOID THIS HAZARDOUS SITUATION. THERE WAS NO TIME FOR EVASIVE ACTION TO BE TAKEN ON MY PART AS IT ALL OCCURRED WITHIN THE SPAN OF 30-45 SECS AND I COULD NOT RAISE SMT Y ON THE RADIO NOR TURN SMA X IN TIME.

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.