Due to the foundation of the LA (Luchtafdeling - Air Department) of the ML-KNIL in Dutch East Indies there was a need for training pilots. That is why Type TT aircraft were ordered from Martin and were delivered in March 1917. Again, it appeared that not all Hall-Scott engines were satisfactory. The last two delivered TT training aircraft (TT-5 and TT-6) were more satisfactory and the training of pilots was started at Kalidjati on Java in the Dutch East Indies. Later, all TTs were fenced into land planes. Here is the profile of the TT-6 with floats from 1917. Also here with the orange roundel and a small number six on the hull.