C208 pilot reported several traffic conflicts with a light sport aircraft at their home airport.

Attributes
ACN	1353909
Time
Date	201512
Local Time Of Day	0601-1200
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Light	Daylight
Aircraft 1
Make Model Name	Caravan Undifferentiated
Operating Under FAR Part	Part 91
Flight Phase	Climb
Route In Use	None
Flight Plan	None
Aircraft 2
Make Model Name	Light Sport Aircraft
Operating Under FAR Part	Part 91
Flight Phase	Climb
Person 1
Function	Single Pilot Pilot Flying
Qualification	Flight Crew Instrument Flight Crew Multiengine Flight Crew Commercial
Experience	Flight Crew Last 90 Days 150 Flight Crew Total 3500 Flight Crew Type 2100
Events
Anomaly	Conflict NMAC Deviation - Procedural Published Material / Policy
Miss Distance	Horizontal 200 Vertical 0

Narrative:

Near mid air collision with light sport [aircraft] when pilot announces west departure from runway 8 on his downwind departure leg westbound cuts across center line of my announced 26 straight out departure; at [this airport] this is common procedure; all local traffic know as well as unicom. Unicom was up at this time. Evasive action taken; immediate left turn away from [conflict aircraft] and towards ridge.I am filing this near mid air incident now as evidence of a systemic problem and following a recent runway incursion. This is the third time (first for me) happened once to other [pilots]. [This light sport pilot] has gone head on into a caravan departing runway 26; the first two times required caravans to abort take off roll; [the pilot] continued runway 8 take off; no communication. This incursion I aborted takeoff roll; and he taxied off the runway and said go ahead.

Original NASA ASRS Text

Title: C208 pilot reported several traffic conflicts with a light sport aircraft at their home airport.

Narrative: Near Mid Air Collision with Light Sport [Aircraft] when pilot announces West departure from runway 8 on his downwind departure leg westbound cuts across center line of my announced 26 straight out departure; at [this airport] this is common procedure; all local traffic know as well as Unicom. Unicom was up at this time. Evasive action taken; immediate left turn away from [conflict aircraft] and towards ridge.I am filing this Near Mid Air incident now as evidence of a systemic problem and following a recent runway incursion. This is the third time (first for me) happened once to other [pilots]. [This Light Sport pilot] has gone head on into a Caravan departing runway 26; the first two times required Caravans to abort take off roll; [the pilot] continued runway 8 take off; no communication. This incursion I aborted takeoff roll; and he taxied off the runway and said go ahead.

Data retrieved from NASA's ASRS site 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.