This is an excerpt from a report made to the Aviation Safety Reporting System. The narrative is written by the pilot, rather than FAA or NTSB officials. To maintain anonymity, many details, such as aircraft model or airport, are often scrubbed from the reports.
Piper Cherokee Pilot’s Narrative
Today we were using Runway XX at ZZZ. Myself and one other plane were using XX. Winds were calm and XX is the wind’s calm runway. Both planes were making comms and we made our announcement of taking the runway.
We were doing a short field takeoff, so holding brakes and throttle full. As we were making our final check, a Citation took Runway YY without making any calls.
We closed the throttle and I immediately got onto the comms and announced to the Citation, “Aircraft X currently on active XX.”
No comms back from the Citation and they started their rolls. I had to take controls and we had no taxiways I could exit off of in time so I taxied close to the grass.
Before pulling off into the grass I saw the Citation had lifted off so I held short of the grass and the Citation climbed out above us as we were on the active runway.
Both myself and the other airplane in the pattern attempted to reach the Citation throughout all of this, but they were not responding or communicating anything.
Citation Captain’s Narrative
While taxiing out, we did not notice any other traffic on the ground or in the air. Wind was calm and we opted to use Runway YY as we were departing to the North.
We called for and received an IFR release from Approach with no other advisories.
We made taxi calls and a departure announcement on comm #1 and communicated with Approach on comm #2.
As we took the runway for departure we did not see any traffic on the runway and proceeded to depart. As we accelerated to V1, I became aware of a Piper type aircraft sitting on the opposite end of the runway with no lights on. I opted to continue the departure as I felt an abort would result in a more likely risk of collision.
After becoming airborne and clear of any risk, I realized that comm #1 was set to XXX.XX instead of the UNICOM frequency. Comm #1 was somehow inadvertently set to the wrong frequency and it was not noticed due to expectation that there was no traffic and thus not uncommon for a lack of radio communications for an early morning departure.
I will be checking and double checking that the correct frequency is entered prior to movement.
Citation First Officer’s Narrative
Taxi for Runway YY with standard calls on comm 1. Comm 1 was set XXX.XX instead of YYY.YY. There was no traffic heard while taxiing and monitoring the correct frequency on comm 2. When I switched frequencies to Departure Clearance on comm 2 we were then monitoring and calling on the wrong frequency on comm 1.
After being cleared for departure I called for Runway YY departing to the east and at about V1 the Piper aircraft had entered the opposite Runway XX.
Upon departure we realized the frequency was incorrect. Comm 1 set inadvertently to the wrong frequency while monitoring the correct frequency on comm 2.
At such an early departure time there is seldom any traffic at the airport and I was not anticipating any.
Making absolutely sure correct frequencies are loaded and then checking them again for accuracy.
Primary Problem: Human Factors