The spare engine power available was marginal in hot atmospheric conditions or when flying through rain, so around 30 G 109A airframes were fitted with a 2,400 cc  Limbach engine and an electrically controlled variable-pitch propeller.
The limited power available for the G 109A aircraft was addressed by fitting them with a 2,400 cc Limbach engine and an electrically controlled variable-pitch propeller in hot or rainy conditions.