Since that time , HT - 18 has been training .
Since that time , HT - 18 has winging Navy , Marine Corps , Coast Guard and select foreign military pilots using the TH - 57B basic helicopter trainer and the TH - 57C advanced helicopter trainer .
Since that time , HT - 18 has been training and winging Navy , Marine Corps , Coast Guard and select foreign military pilots using the TH - 57B basic helicopter trainer and the TH - 57C advanced helicopter trainer .