BL30 pilot began to lose engine oil, while doing aerobatics.

Attributes
ACN	420156
Time
Date	199811
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : vuh
State Reference	TX
Altitude	msl bound lower : 4000 msl bound upper : 4000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : hou
Operator	general aviation : personal
Make Model Name	Decathlon
Operating Under FAR Part	Part 91
Flight Phase	cruise other
Flight Plan	None
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private
Experience	flight time last 90 days : 22 flight time total : 120 flight time type : 59
ASRS Report	420156
Person 2
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	other flight crewa
Resolutory Action	other
Consequence	faa : investigated
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

During primary flight training, my instructors repeatedly cautioned me not to 'over tighten' dipsticks in lycoming engines. Neither the engine manufacturer nor the airplane's builder provided definite information as to how these dipsticks should be secured. After approximately 30 mins of aerobatic flight, and while in sustained level inverted flight, the dipstick in the engine vibrated loose. Approximately 4 quarts of oil were lost before landing. Engine oil pressure and temperature remained normal. I believe that this situation could have been prevented by proper training in regards to securing these dipsticks or by positive guidance in the aircraft reference manuals as to properly tightening these dipsticks before aerobatic flight.

Original NASA ASRS Text

Title: BL30 PLT BEGAN TO LOSE ENG OIL, WHILE DOING AEROBATICS.

Narrative: DURING PRIMARY FLT TRAINING, MY INSTRUCTORS REPEATEDLY CAUTIONED ME NOT TO 'OVER TIGHTEN' DIPSTICKS IN LYCOMING ENGS. NEITHER THE ENG MANUFACTURER NOR THE AIRPLANE'S BUILDER PROVIDED DEFINITE INFO AS TO HOW THESE DIPSTICKS SHOULD BE SECURED. AFTER APPROX 30 MINS OF AEROBATIC FLT, AND WHILE IN SUSTAINED LEVEL INVERTED FLT, THE DIPSTICK IN THE ENG VIBRATED LOOSE. APPROX 4 QUARTS OF OIL WERE LOST BEFORE LNDG. ENG OIL PRESSURE AND TEMP REMAINED NORMAL. I BELIEVE THAT THIS SIT COULD HAVE BEEN PREVENTED BY PROPER TRAINING IN REGARDS TO SECURING THESE DIPSTICKS OR BY POSITIVE GUIDANCE IN THE ACFT REF MANUALS AS TO PROPERLY TIGHTENING THESE DIPSTICKS BEFORE AEROBATIC FLT.

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.