A C182 pilot reported an ultralight's erratic landing pattern at L17.

Attributes
ACN	571438
Time
Date	200301
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : l17.airport
State Reference	CA
Altitude	msl single value : 1700
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : personal
Make Model Name	Skylane 182/RG Turbo Skylane/RG
Operating Under FAR Part	Part 91
Flight Phase	descent : approach
Route In Use	approach : visual approach : traffic pattern
Aircraft 2
Operator	general aviation : personal
Make Model Name	Ultralight
Operating Under FAR Part	Part 91
Flight Phase	climbout : intermediate altitude
Flight Plan	VFR
Person 1
Affiliation	other
Function	flight crew : single pilot
Qualification	pilot : multi engine pilot : instrument pilot : cfi pilot : atp pilot : commercial
Experience	flight time last 90 days : 300 flight time total : 4700 flight time type : 3000
ASRS Report	571438
Person 2
Affiliation	other
Function	flight crew : single pilot
Events
Anomaly	conflict : airborne critical non adherence : far other spatial deviation
Independent Detector	other flight crewa
Resolutory Action	flight crew : took evasive action
Miss Distance	horizontal : 900 vertical : 500
Supplementary
Problem Areas	Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance

Narrative:

C182 radio called 45 degree leg entry, downwind to runway 25 at taft kern airport (L17). Ultralight sighted and kept in sight. As it departed runway 7 at L17 airport, C182 requested that ultralight start right crosswind at departure end of runway 7, and the ultralight turned crosswind. However, ultralight continued a right turn to complete a 180 degree maneuver turn back onto the centerline of runway 25 at L17 airport, overflying at about 200 ft above runway. C182 was on final for runway 25 and inquired on CTAF 122.8 'what are your intentions ultralight?' no answer from ultralight pilot. Ultralight landed on far end of runway 25. C182 landed on runway 25, on the numbers to avoid conflicting traffic. The ultralight was using a very nonstandard traffic pattern and did indeed present a hazard to the normal GA traffic flow at L17 airport.

Original NASA ASRS Text

Title: A C182 PLT RPTED AN ULTRALIGHT'S ERRATIC LNDG PATTERN AT L17.

Narrative: C182 RADIO CALLED 45 DEG LEG ENTRY, DOWNWIND TO RWY 25 AT TAFT KERN ARPT (L17). ULTRALIGHT SIGHTED AND KEPT IN SIGHT. AS IT DEPARTED RWY 7 AT L17 ARPT, C182 REQUESTED THAT ULTRALIGHT START R XWIND AT DEP END OF RWY 7, AND THE ULTRALIGHT TURNED XWIND. HOWEVER, ULTRALIGHT CONTINUED A R TURN TO COMPLETE A 180 DEG MANEUVER TURN BACK ONTO THE CTRLINE OF RWY 25 AT L17 ARPT, OVERFLYING AT ABOUT 200 FT ABOVE RWY. C182 WAS ON FINAL FOR RWY 25 AND INQUIRED ON CTAF 122.8 'WHAT ARE YOUR INTENTIONS ULTRALIGHT?' NO ANSWER FROM ULTRALIGHT PLT. ULTRALIGHT LANDED ON FAR END OF RWY 25. C182 LANDED ON RWY 25, ON THE NUMBERS TO AVOID CONFLICTING TFC. THE ULTRALIGHT WAS USING A VERY NONSTANDARD TFC PATTERN AND DID INDEED PRESENT A HAZARD TO THE NORMAL GA TFC FLOW AT L17 ARPT.

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.