Narrative:

The sky was clear; visibility was unlimited; and winds were reported as 270 at 8. One other aircraft was in the pattern as I taxied; and I held short for his landing on runway 26. When he reported clear of the runway; I announced that I was taking runway 26 for a downwind departure. No other traffic was visible in the pattern or making calls on CTAF at this point. After takeoff and still on my departure leg; another aircraft called to announce that he was going to make a crosswind entry to the pattern. Thinking he might not have heard my initial call from the ground; I announced my crosswind turn and restated my intention to make a downwind departure. Hearing no response; I decided to climb through pattern altitude and keep an eye out for traffic entering the pattern. I was at or past pattern altitude as I turned downwind. Once established on a climbing downwind; I spotted the traffic on the midfield crosswind; I estimate 200 or 300 feet below me. I called that I had him in sight and was continuing my climb; at this point he was turning left onto the downwind and I lost sight of him below me. Had I remained at pattern altitude and we had continued our courses; this would have been a _very_ close encounter. At this point an aircraft operating over lake winnipesaukee called to announce his position since I was climbing towards the lake. This then took my attention; I acknowledged his call and stated my further intentions. There was no further contact or conflict with traffic in the pattern. My initial reaction to the encounter is to admonish the other pilot for not listening or showing situational awareness. CTAF is great for making traffic advisories; but it's just as good for hearing traffic advisories. Listen; because that other voice might be announcing that they're coming at you! On review; there are a couple of things I could have done differently. First; I could have changed my plan and departed the pattern to the west and turned on course once I was well clear of the pattern. My hesitation to do this came from the fact that I had already announced my intention to depart downwind; and if anyone else was listening; that's what they were expecting me to do. Especially after my second call; I felt that it was more sensible to be predictable and to keep an eye out for traffic I knew was there rather than to change my plan and surprise traffic that was paying attention. I also hoped -- expected; in fact -- that the other aircraft would respond or at least keep a sharp eye out. So in hindsight perhaps I should have departed the pattern earlier; but I don't second guess my decision at the time. I suspect I'll be debating this point with myself for some time to come. Second; and much less ambiguous; was my decision to continue my climb on downwind after I lost sight of the other aircraft under me. My assumption was that he would stay at pattern altitude and turn base while I kept climbing straight ahead (terrain makes it difficult for me to turn right at this point). In my head; separation was assured; and that was the end of it. But why would I choose to lose sight of an aircraft with only a few hundred feet vertical separation?! It would have taken some maneuvering to keep him in sight at that point; but without a two-way dialog on CTAF and without visual contact; an assumption and a mental picture isn't the best thing to rely on.

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Original NASA ASRS Text

Title: Light aircraft pilot reported NMAC with another light aircraft on departure from LCI.

Narrative: The sky was clear; visibility was unlimited; and winds were reported as 270 at 8. One other aircraft was in the pattern as I taxied; and I held short for his landing on runway 26. When he reported clear of the runway; I announced that I was taking runway 26 for a downwind departure. No other traffic was visible in the pattern or making calls on CTAF at this point. After takeoff and still on my departure leg; another aircraft called to announce that he was going to make a crosswind entry to the pattern. Thinking he might not have heard my initial call from the ground; I announced my crosswind turn and restated my intention to make a downwind departure. Hearing no response; I decided to climb through pattern altitude and keep an eye out for traffic entering the pattern. I was at or past pattern altitude as I turned downwind. Once established on a climbing downwind; I spotted the traffic on the midfield crosswind; I estimate 200 or 300 feet below me. I called that I had him in sight and was continuing my climb; at this point he was turning left onto the downwind and I lost sight of him below me. Had I remained at pattern altitude and we had continued our courses; this would have been a _very_ close encounter. At this point an aircraft operating over Lake Winnipesaukee called to announce his position since I was climbing towards the lake. This then took my attention; I acknowledged his call and stated my further intentions. There was no further contact or conflict with traffic in the pattern. My initial reaction to the encounter is to admonish the other pilot for not listening or showing situational awareness. CTAF is great for making traffic advisories; but it's just as good for hearing traffic advisories. Listen; because that other voice might be announcing that they're coming at you! On review; there are a couple of things I could have done differently. First; I could have changed my plan and departed the pattern to the west and turned on course once I was well clear of the pattern. My hesitation to do this came from the fact that I had already announced my intention to depart downwind; and if anyone else was listening; that's what they were expecting me to do. Especially after my second call; I felt that it was more sensible to be predictable and to keep an eye out for traffic I knew was there rather than to change my plan and surprise traffic that was paying attention. I also hoped -- expected; in fact -- that the other aircraft would respond or at least keep a sharp eye out. So in hindsight perhaps I should have departed the pattern earlier; but I don't second guess my decision at the time. I suspect I'll be debating this point with myself for some time to come. Second; and much less ambiguous; was my decision to continue my climb on downwind after I lost sight of the other aircraft under me. My assumption was that he would stay at pattern altitude and turn base while I kept climbing straight ahead (terrain makes it difficult for me to turn right at this point). In my head; separation was assured; and that was the end of it. But why would I choose to lose sight of an aircraft with only a few hundred feet vertical separation?! It would have taken some maneuvering to keep him in sight at that point; but without a two-way dialog on CTAF and without visual contact; an assumption and a mental picture isn't the best thing to rely on.

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.