Date: 202008
Local time of day: 0601-1200
Location: AWO.Airport, WA
Flight conditions: VMC
Light: Daylight
Aircraft: Aerobatic
Operator: Personal
Operating under: Part 91
Flight plan: None
Mission: Training
Flight phase: Landing
ATC / advisory: CTAF AWO
Second aircraft: Small Aircraft
Reporter organization: Personal
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Flight Instructor; Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Commercial
Human factors: Situational Awareness; Communication Breakdown; Confusion; Training / Qualification
Anomaly: Conflict NMAC; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural FAR
Detector: Person Other Person
When detected: Other Landing
Result: Flight Crew Executed Go Around / Missed Approach; Flight Crew Took Evasive Action
Contributing factors: Human Factors; Airport
Primary problem: Human Factors

Narrative: A fellow flight instructor and I were landing at Arlington airport when we experienced a runway incursion. On final approach to Runway 16 we noticed Aircraft Z holding short of Runway 16 for takeoff. Moments later; on short final over Runway 16 at approximately 50 ft. I heard a radio transmission 'Aircraft X; you got Aircraft Y taking off on 34'. The source of this transmission is unknown; but we think it was Aircraft Z.There is no forward visibility when landing this type of biplane; and since I could not see the unidentified Aircraft Y; we aborted the landing and executed an immediate go-around at low altitude over the runway. We adjusted course to offset to the right of the runway so we could attempt to spot this aircraft since we could not see over the nose. That is the first time we saw the white Aircraft Y who was in the takeoff roll heading directly towards us. We announced on the radio that we were going-around due to opposite-direction traffic on the runway. We saw Aircraft Y make a left and right swerving turn on the runway in an apparent attempt to get to one side of the runway and then immediately after that we saw Aircraft Y continue the takeoff roll as he disappeared from view underneath us.We continued to fly a normal pattern for Runway 16. Announcing our position at each leg of the pattern.Upon turning downwind we observed the subject Aircraft Y flying upwind for runway 16. We asked the pilot what his intentions were. We were concerned he may stay in the pattern and cause additional collision risk. An unidentified aircraft; presumably Aircraft Y; responded 'Runway 34 is the calm wind runway. Winds are CALM! I guess I'll just depart to the west. Aircraft X; give me your tail number!' This was the first transmission that we believe came from the subject aircraft. We chose not to respond to this aircraft; and focused on keeping the traffic in sight; and our aircraft under control.Moments later another unidentified aircraft transmitted 'The AWOS is reporting winds from the south. The winds are not calm. I'm about to takeoff on 16'The subject Aircraft Y left the area; and no further radio transmissions were heard from that aircraft. We landed safely on Runway 16. After touchdown we noticed the windsock showing a light wind; 5-10 mph; from the south; favoring Runway 16.I believe the Aircraft Y pilot used the existence of a calm wind runway designation to attempt to force aircraft to use another runway that was not optimally aligned with the local winds. This pilot did not follow 14 CFR 91.113. It is clear Aircraft Y's pilot had an operable radio; but did not use it to announce his intention to use a runway that would create a collision hazard. I believe the local calm wind runway policy may have also affected Aircraft Y's pilot's judgement; and created a confirmation bias that caused him to do what he did.Arlington Airport is busy. The airport has a local reputation of sometimes being out of control. Some locals call it 'Anarchy Acres'. I know flight instructors who will not let their students go there alone. I have seen pilots landing on runways that are not in use by the majority of traffic. I've heard reasons like 'It takes too long to taxi to my hangar; so I just use runway X every time.' These are hazardous attitudes. This kind of activity makes me concerned for the general safety of all pilots flying at this airport.As this airport becomes busier and busier the FAA should evaluate the need for a control tower at the field to prevent a serious accident from happening. Alternatively; the FAA or the City should study the flow of traffic at this airport to help better understand why these events happen. The cost/benefit analysis of the calm wind runway guidance should be re-evaluated; especially since there are crossing runways at this airport with a track record of similar problems in the ASRS database.




Synopsis: Pilot reported encountering opposite direction traffic at uncontrolled airport.