Pilot reported on take off roll he saw another aircraft opposite direction cross the hold short line...

Narrative:

At xa:10 local time; I made my communication to enter runway xx at ZZZ. I checked to make sure the runway was clear and there was no traffic inbound for landing that had not communicated on the field frequency. I was practicing a short field takeoff; so I rolled onto the runway without stopping and applied full power and pitched up. After I had rolled about 100 feet; I noticed a small; tricycle gear; experimental aircraft cross the hold short line and pull onto runway yy. I promptly aborted my takeoff and back-taxied to the beginning of the runway and exited on the taxiway. The other pilot also turned around and exited the runway. I taxied back across the hold short line and turned my aircraft around. I then attempted to radio and communicate on [frequency] to talk to the other aircraft and coordinate an order of departure. I made several calls and eventually they communicated on the radio. Their signal was somewhat broken; but we were able to resolve the scenario and safely coordinate who would take off first. The pilot of the experimental aircraft insisted that I take the runway and depart and first and apologized for entering the active runway without communicating. No injuries or damage occurred. The entire event could have been avoided by the pilot of the experimental aircraft listening to and communicating on the field frequency and looking for traffic on the runway before crossing the hold short line.

Original NASA ASRS Text

Title: Pilot reported on take off roll he saw another aircraft opposite direction cross the hold short line and attempt to line up.

Narrative: At XA:10 Local time; I made my communication to enter runway XX at ZZZ. I checked to make sure the runway was clear and there was no traffic inbound for landing that had not communicated on the field frequency. I was practicing a short field takeoff; so I rolled onto the runway without stopping and applied full power and pitched up. After I had rolled about 100 feet; I noticed a small; tricycle gear; experimental aircraft cross the hold short line and pull onto runway YY. I promptly aborted my takeoff and back-taxied to the beginning of the runway and exited on the taxiway. The other pilot also turned around and exited the runway. I taxied back across the hold short line and turned my aircraft around. I then attempted to radio and communicate on [frequency] to talk to the other aircraft and coordinate an order of departure. I made several calls and eventually they communicated on the radio. Their signal was somewhat broken; but we were able to resolve the scenario and safely coordinate who would take off first. The pilot of the experimental aircraft insisted that I take the runway and depart and first and apologized for entering the active runway without communicating. No injuries or damage occurred. The entire event could have been avoided by the pilot of the experimental aircraft listening to and communicating on the field frequency and looking for traffic on the runway before crossing the hold short line.

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.

Attributes
ACN	1757717
Time
Date	202008
Local Time Of Day	0601-1200
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Light	Daylight
Aircraft 1
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Flight Phase	Takeoff
Route In Use	Direct
Flight Plan	VFR
Aircraft 2
Make Model Name	Amateur/Home Built/Experimental
Flight Phase	Takeoff
Person 1
Function	Single Pilot
Qualification	Flight Crew Student
Experience	Flight Crew Last 90 Days 31 Flight Crew Total 51 Flight Crew Type 32
Events
Anomaly	Conflict Ground Conflict Critical Deviation - Procedural Published Material / Policy Ground Incursion Runway
Miss Distance	Horizontal 4000