Date: 202011
Local time of day: 1201-1800
Location: GAI.Airport, MD
Flight conditions: VMC
Weather elements / visibility: 10
Light: Daylight
Aircraft: Small Aircraft; Low Wing; 1 Eng; Fixed Gear
Operator: Personal
Operating under: Part 91
Flight plan: None
Mission: Training
Flight phase: Landing
Airspace: Class G GAI
ATC / advisory: CTAF GAI
Second aircraft: Small Transport
Reporter organization: Personal
Reporter function: Single Pilot
Reporter qualification: Flight Crew Instrument; Flight Crew Private
Human factors: Communication Breakdown
Anomaly: Conflict Airborne Conflict; Conflict Ground Conflict; Less Severe; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Became Reoriented
Contributing factors: Airspace Structure; Airport; Human Factors
Primary problem: Ambiguous

Narrative: I file this report for two reasons: to note a particular pilot's decision-making; and to talk about a larger potentially dangerous airport-environment situation.  Here is the relevant data:- The airport in question is Montgomery County Airpark; in Gaithersburg; Maryland; GAI. It is a very busy *uncontrolled* airport. It is within the DC SFRA; so pilots must obtain a discrete transponder code from Potomac Approach before taking off; and before re-entering the SFRA from outside. - The airport's only runway is 32/14; about 4000 feet long. The airport ATIS specifies that Runway 14 is preferred in calm-wind conditions. Also; the only approach to GAI is an RNAV/LPV approach to Runway 14. - There is a very; very active primary-training type airport. Nearly all of its students are [from] overseas; and the frequency of their flight means that the traffic-pattern at the airport is usually 'full.' It is typical to have one plane doing a runup; another taking off; another on downwind turning to base; and two or three others approaching from the north; all at the same time.- On the morning of this incident; winds had been in the 5 kt range--but from the north. So traffic through the morning had been all on Runway 32. - Now; the time in question. It was about XA:00 local EST. I was approaching from the north; and I received a code for entering the SFRA from Potomac Approach. As is usual practice; when I was about 12 miles north of GAI; I told Potomac; 'Gaithersburg in sight;' and they gave the formulaic response: 'Stay on discrete transponder code until landing; remain outside Class Bravo; switch to local frequency approved.' So I switched to the local UNICOM; 123.075.-I heard on the frequency what I also saw on my ADS-B display: That the pattern was; as usual; 'busy;' with three or four planes at various points in the circuit. And all of them were using Runway 32. (The winds at that moment were reporting calm on ATIS; but the pattern had been in steady use all day; on 32.)-Over the next eight minutes or so; between first radio contact and landing; I noticed two recurrent phenomena. One was many planes reporting their progress and position in a pattern for Runway 32.  I made calls; beginning at 8 miles out; with intentions to follow the established local practice. ('Forty-five to join right downwind for Runway 32.') The other notable entry was one airplane (Airplane X) that reported it was to the west; and 'straight in landing; Runway 14.'-A plane reports 'downwind 32.' Aircraft X says; 'straight in; Runway 14.' Another plane says; 'Aircraft X; we are using 32; please circle to land.' Aircraft pilot says; 'Straight in Runway 14.' At least twice; and I think three times; flight instructors say 'Aircraft X; PLEASE circle to land 32. We are all using 32.' Aircraft X replies; 'Straight in; 14.'-I kept reporting my own position; and said at one point 'Aircraft X; I am turning base to final for landing 32.' At that point I could see him descending to 14 -- i.e.; head on. The distances were such that it was clear to me that I could land safely and normally; and get off the runway; before he got too close.   And I proceeded to land. I turned off the runway halfway down; while he was still probably a mile out on opposite-direction final. All the other planes in the Runway 32 pattern extended their downwind etc.; to land. -The two planes landed at XA:07 pm EST; but in opposite directions.-Later; I saw someone who I assumed to be the Aircraft X pilot. He was; and I asked him: 'Why did you do that?' His answer was that he was fine-tuning the coupled-autopilot and wanted to fly an approach all the way down. -Note: I have been in this situation myself too; wanting to check out autopilots. But I choose airports where I can do so in keeping with the local traffic flow. -The main problem in this scenario was the Aircraft X pilot; who insisted on plowing ahead despite repeated requests on the frequency to switch to join the busy local traffic flow. I realize this is not an 'enforcement' forum; and I mention it just FYI.-The larger point is that the Gaithersburg airport has become unsustainably busy; for its uncontrolled status.  I have landed there probably X times over the past XX years. I *always* view the most challenging part of any trip to be the final 10 minutes of trying to fit into the uncontrolled but increasingly busy traffic pattern there.  With many primary students in training; they're often doing unexpected things in the pattern; or are uncertain in radio calls. Suggestion / request: Sooner or later there is going to be some safety incident at this airport; coming from too much traffic with too little control. A tower controller would *never* have allowed the situation I'm reporting to emerge. This is a problem waiting to happen at this airport.




Synopsis: GA pilot reported that while landing at an uncontrolled airport another aircraft landed on the same runway; opposite direction. Reporter stated the airport was always busy and should become a tower-controlled airport.