Air taxi flight crew reported a NMAC during takeoff involving opposite direction traffic at a non-towered airport.
Synopsis
Air taxi flight crew reported a NMAC during takeoff involving opposite direction traffic at a non-towered airport.
Narrative
We had a flight scheduled from ZZZ to ZZZ1 with a fuel stop in ZZZ2. I flew the first leg and we landed runway XX in ZZZ2. On the ground in ZZZ2 we noticed that the winds have shifted and now favored runway XY. It's also important to note that runway XY is the preferred take off runway. The captain and I had briefed to do the ZZZ2 ODP (Obstacle Departure Procedure). Upon getting fuel and closing the door; we finished our checklists followed our procedures and started the engines. We briefed the taxi to runway XY and I made a radio call saying that we were taxing from the FBO to runway XY. We had to cross runway XZ/XA so we looked left and right and I made the appropriate radio cal to let the CTAF know we were crossing the runway. Once clear of the runway I made another radio call. Shortly after crossing we were number 2 behind a large jet that was waiting to get their clearance to also depart runway XY. Once behind the large jet I called center on Comm 1 however I still listened to CTAF on comm 2 the captain was also listening to both frequencies. Center told me we were waiting for a airplane to land opposite direction with a tailwind" runway XX so we couldn't depart runway XY. Once that aircraft landed the large jet took the runway and departed. Center told me to expect a 3 minute delay before I would receive my IFR release. 3 minutes later we get the release they tell us to climb to 10;000 feet and they also gave us a squawk code. The captain and I briefed the changes for the departure looked left and right and prior to crossing the hold short makings I made a radio call saying we were going to be a climbing left turn then a right turn up to 10;000 feet. We heard no other radio call prior to our transmission or after our transmission that there was any other airplane near the ZZZ2 airport. We confirmed XY was the correct runway looked left and right and I spun the MFD (Multi-Function Flight Display) to display a 10 mile radius to show us any traffic or hazards. We saw nothing and took off. The captain called power set I called 70 and accelerating towards V1 the captain said is that an airplane. Before we could make it out it was too late we were past V1 had to continue. The captain lifted the airplane very slowly into the air keeping it within feet of the ground as the other airplane passed dangerously close. I asked if that other airplane was on frequency he said he was. I then made our last radio call and we made it to ZZZ1 safely."
Second reporter narrative
We were scheduled to fly passengers from ZZZ - ZZZ1 via a fuel stop in ZZZ2. Upon arrival in ZZZ2 we requested a quick turn; took fuel; programmed the aircraft; briefed and dual verified our departure and obstacle departure procedure for the leg to ZZZ1. I was pilot flying and the FO was pilot monitoring for this leg.Winds at the time of departure were reported at 320 @ 5kts. Runways XX & XY are listed as the preferred runways for departure. In addition; runways XZ & XA are listed as the preferred runways for arrivals. After engine start and the completion of our checklists; we made our appropriate radio call and proceeded to taxi behind a large jet flight to runway XX while monitoring both Unicom and center frequencies. We proceeded to cross runway XA/XB and again made our appropriate radio call to announce our crossing. We reached runway XX number two in sequence behind the large jet who was communicating with arriving VFR traffic 13 miles out on the ILS to XZ for a full stop. We called center and received a hold for release clearance and were advised of the large jet and the incoming VFR traffic. After the traffic arrived and called clear of the runway; the large jet inquired and received their release for departure. Center advised us to expect an approximate 3 minute delay prior to receiving our release. We held short of runway XX and monitored both frequencies. I noted that there were birds circling the end of the runway and took note to monitor them on departure. After a short time center released us for departure. We proceeded to make our radio call; taking the active runway XX for departure; verified the area was clear to the left and right; and taxied into position. It is worth noting that we could not see the departure end of runway XZ from the departure end of XX as the runway appears to crest. We verified runway XX was correct; and the FO dialed out the MFD (Multi-Function Flight Display) scale. There was no traffic indicating on the TCAS system; and neither of us heard any traffic calls for ZZZ2 airport. Power was set and we began our takeoff roll. The 70" call was made. As we were passing V1; I stated; "Is that a [expletive] airplane!" There was a mirage effect on the runway; and I was not 100% sure if what I saw was an aircraft or the birds I noted prior to departure. I quickly determined this was in fact an aircraft; but was not sure if the aircraft was arriving or departing runway XZ. I opted to hold the aircraft on and near the ground until I determined what scenario we were in. We quickly figured out the oncoming aircraft was either in a missed approach or takeoff configuration; and I opted to pass under the opposite direction traffic. We accelerated through approximately 160 kts indicated; passed under the aircraft and continued our takeoff after crossing paths. We continued on the obstacle departure for ZZZ2. Upon takeoff; the FO queried the departing aircraft. They responded jet traffic departing ZZZ2 did you hear our radio calls; we responded in the negative; and they asked if we made any radio calls to which we responded yes; plenty of them. We then left the frequency to contact Center. No erratic maneuvers were initiated; no limitations were exceeded and the passengers were never aware or made aware of any incident. We continued the flight and landed in ZZZ1 without further incident.As I replay this scenario in my head; there are only a couple suggestions and factors that we had control of that I can think of. First; the selection of ZZZ2 as a fuel stop location. In our operations small uncontrolled fields are a necessary known. However that does not mean we need to unnecessarily increase activity to those locations. From a risk analysis perspective; avoiding these fields when able lowers our potential interactions with this type of increased risk operations. Whereas the small slower airfield has benefits from a straight line stopover point; and a quick turn perspective; in the future I will look at a larger tower controlled field for fuel stops. Secondly; there are a couple knowns. The Unicom Frequency is a heavily congested frequency; and it is important to not tie up these frequencies with nonessential calls. And; I understand the AIM recommends to not ask any traffic in the area to respond for that reason. What I do not know; is if we did transmit into the blind with this request; maybe more radio calls could have changed the outcome? I will continue to follow the recommendation of the AIM as I am sure it is a calculated cost vs reward equation. And I do not know the answer here; but I do feel something needs to change in this area. I cannot 100% guarantee transmissions were not made by this other aircraft; but I can 100% guarantee that we were monitoring and did not hear them; In addition; I would hope that the pilot in the other aircraft did not hear ours... On an afternoon we are all familiar with the increased traffic of GA aircraft; is it possible that these transmission were blocked by the continuous transmissions from the skydiving operation; or the other area airports operations? I feel that something can be done better to maintain safe and efficient communications.Besides this; I feel that the holes in the Swiss cheese just all lined that day. Fortunately; we had factors that worked in our favor and tragedy was avoided."
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.