La Costeña (tel. 505/2263-2142, 505/2263-2143, or 505/2263-2144, reservacion [at] lacostena [dot] com [dot] ni, www.lacostena.com.ni [1]) is Nicaragua’s sole domestic airline, whose humble fleet of seven small craft fly between Managua [2] and the Atlantic coast, Mining Triangle, Puerto Cabezas, Waspám, Bluefields, Corn Island, and San Carlos [3].
Seats are limited on the 12-passenger twin-prop Cessna Grand Caravans (they have one 40-passenger Short 360 aircraft as well), and cost about $80 one-way, $120–160 round-trip.
It is almost imperative that you reserve your flight before arriving in Nicaragua; this has been difficult in the past, but La Costeña’s new online booking system will help matters.
Links:
[1] http://www.lacostena.com.ni
[2] http://www.moon.com/destinations/nicaragua/managua
[3] http://www.moon.com/destinations/nicaragua/rio-san-juan/san-carlos