A pilot was detouring a thunderstorm and climbed above assigned altitude near mth. A learjet crossed...

Attributes
ACN	439280
Time
Date	199906
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : mth.airport
State Reference	FL
Altitude	msl bound lower : 12000 msl bound upper : 12700
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : mia.tracon
Operator	general aviation : personal
Make Model Name	Small Transport, Low Wing, 2 Turboprop Eng
Operating Under FAR Part	Part 91
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Aircraft 2
Operator	general aviation : corporate
Make Model Name	Gates Learjet Corp Undifferentiated or Other Model
Operating Under FAR Part	Part 91
Flight Phase	cruise : level
Route In Use	enroute other
Flight Plan	IFR
Person 1
Affiliation	other
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : multi engine pilot : commercial
Experience	flight time last 90 days : 20 flight time total : 1500 flight time type : 20
ASRS Report	439280
Person 2
Affiliation	company : corporate
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : airborne less severe inflight encounter : weather non adherence : clearance
Independent Detector	other flight crewa
Resolutory Action	flight crew : returned to assigned airspace
Miss Distance	horizontal : 6000 vertical : 300
Supplementary
Problem Areas	Flight Crew Human Performance Weather
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

During climb altitude assigned 12000 ft. Just before reaching altitude, began deviation west to avoid cell thunderstorm. During deviation, had sudden climb in vertical speed. Not sure if it was turbulence or autoplt gremlins. Disconnected autoplt and returned to 12000 ft from 12600-12700 ft. Event caused by turbulence, autoplt catch and compounded by diverting attention from climb out. As assigned altitude was reached, other traffic, learjet(?) was crossing at 13000 ft and appeared to be at about 1 mi. Horizontal spacing no real danger at any time.

Original NASA ASRS Text

Title: A PLT WAS DETOURING A TSTM AND CLBED ABOVE ASSIGNED ALT NEAR MTH. A LEARJET CROSSED WITHIN 1 NM.

Narrative: DURING CLB ALT ASSIGNED 12000 FT. JUST BEFORE REACHING ALT, BEGAN DEV W TO AVOID CELL TSTM. DURING DEV, HAD SUDDEN CLB IN VERT SPD. NOT SURE IF IT WAS TURB OR AUTOPLT GREMLINS. DISCONNECTED AUTOPLT AND RETURNED TO 12000 FT FROM 12600-12700 FT. EVENT CAUSED BY TURB, AUTOPLT CATCH AND COMPOUNDED BY DIVERTING ATTN FROM CLBOUT. AS ASSIGNED ALT WAS REACHED, OTHER TFC, LEARJET(?) WAS XING AT 13000 FT AND APPEARED TO BE AT ABOUT 1 MI. HORIZ SPACING NO REAL DANGER AT ANY 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.

A pilot was detouring a thunderstorm and climbed above assigned altitude near mth. A learjet crossed within 1 NM.