"external-link">summarise</a></span><span class="op">(</span><span class="va">by_tailnum</span>,</span>
<span>  count <span class="op">=</span> <span class="fu"><a href="https://dplyr.tidyverse.org/reference/context.html" class="external-link">n</a></span><span class="op">(</span><span class="op">)</span>,</span>
<span>  dist <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/mean.html" class="external-link">mean</a></span><span class="op">(</span><span class="va">distance</span>, na