HS125 crew reports near midair collision with L29 at 3000 ft below atl class B airspace.

Attributes
ACN	719917
Time
Date	200612
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : mge.airport
State Reference	GA
Altitude	msl single value : 2000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : a80.tracon tower : mem.tower
Operator	common carrier : air taxi
Make Model Name	BAe 125 Series 800
Operating Under FAR Part	Part 91
Navigation In Use	other
Flight Phase	descent : approach
Route In Use	approach : visual
Flight Plan	IFR
Aircraft 2
Operator	general aviation : personal
Make Model Name	Military Trainer
Operating Under FAR Part	Part 91
Flight Phase	climbout : takeoff cruise : level
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : flight engineer pilot : atp
Experience	flight time last 90 days : 150 flight time total : 11000 flight time type : 150
ASRS Report	719917
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Events
Anomaly	conflict : nmac
Independent Detector	other flight crewa
Miss Distance	horizontal : 50 vertical : 300
Supplementary
Problem Areas	Flight Crew Human Performance Airspace Structure
Primary Problem	Flight Crew Human Performance

Narrative:

On a reposition flight from pdk to fty and about 5 NM southeast of dobbins AFB at 3000 ft MSL we watched an aircraft perform a smoke-on; vertical climb from low altitude to our altitude and then head directly toward us. We received a 'monitor vertical rate' call from our TCAS followed immediately by a 'descend; descend' call. The pilot monitoring called ATC with our RA descent. Green band was at 3000-4000 FPM down and I complied till 2600 ft MSL where we got a 'clear of conflict' call. We then returned back to 3000 ft MSL and continued to our destination. Fortunately for the smoke coming from the target aircraft we got a visual early and maintained a visual as the L29 passed overhead. L29's are real popular with the sport aircraft crowd and this was poor judgement on this pilot's part to be performing aerobatics over a densely populated area under atlanta's class B airspace in the vicinity of so many satellite airports.

Original NASA ASRS Text

Title: HS125 CREW RPTS NMAC WITH L29 AT 3000 FT BELOW ATL CLASS B AIRSPACE.

Narrative: ON A REPOSITION FLT FROM PDK TO FTY AND ABOUT 5 NM SE OF DOBBINS AFB AT 3000 FT MSL WE WATCHED AN ACFT PERFORM A SMOKE-ON; VERT CLB FROM LOW ALT TO OUR ALT AND THEN HEAD DIRECTLY TOWARD US. WE RECEIVED A 'MONITOR VERT RATE' CALL FROM OUR TCAS FOLLOWED IMMEDIATELY BY A 'DSND; DSND' CALL. THE PLT MONITORING CALLED ATC WITH OUR RA DSCNT. GREEN BAND WAS AT 3000-4000 FPM DOWN AND I COMPLIED TILL 2600 FT MSL WHERE WE GOT A 'CLR OF CONFLICT' CALL. WE THEN RETURNED BACK TO 3000 FT MSL AND CONTINUED TO OUR DEST. FORTUNATELY FOR THE SMOKE COMING FROM THE TARGET ACFT WE GOT A VISUAL EARLY AND MAINTAINED A VISUAL AS THE L29 PASSED OVERHEAD. L29'S ARE REAL POPULAR WITH THE SPORT ACFT CROWD AND THIS WAS POOR JUDGEMENT ON THIS PLT'S PART TO BE PERFORMING AEROBATICS OVER A DENSELY POPULATED AREA UNDER ATLANTA'S CLASS B AIRSPACE IN THE VICINITY OF SO MANY SATELLITE ARPTS.

Data retrieved from NASA's ASRS site as of January 2009 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.