
August Ferdinand Howaldt (23 October 1809 – 4 August 1883) was a German engineer and ship builder. The German sculptorGeorg Ferdinand Howaldt was his brother.
Born inBraunschweig, the son of the silversmith David Ferdinand Howaldt, with whom he got his first practice working in metal, Howaldt made an apprenticeship inHamburg and became apractical mechanicus.

In 1838 he moved toKiel, where he married Emma Diederichsen. In Kiel he founded together with the Kiel entrepreneurJohann Schweffel [de] the "Maschinenbauanstalt Schweffel & Howaldt", a company initially building boilers for industry and the new railroad companies in between Hamburg and Kiel and agricultural machinery for the surrounding estates inHolstein.
In 1849 Schweffel & Howaldt built its first steam engine for naval purposes for theVon der Tann, a gunboat for the small navy ofSchleswig-Holstein, and theBrandtaucher, the first German incendiary diver orsubmarine designed byWilhelm Bauer. TheBrandtaucheris today an exhibit of theGerman Forces Military History Museum inDresden. Schweffel & Howaldt also built two tugs in 1860 and 1864. When he passed his company to his sons Georg, Bernhard andHermann Howaldt, who continued in 1879 under the name Gebrüder Howaldt. The firm merged with Georg's shipyard in Kiel in 1889 to become Howaldtswerke AG, today known asHowaldtswerke-Deutsche Werft (HDW).