05/15/2013. Remarks by Johan Visschedijk: "In 1958 the Danish civil engineer Harald Thyregod finished the design of this aircraft, intended for inexpensive and easy to construct homebuilding. Construction was done by Arne Hollænder, assisted by Aksel Smidt, hence the aircraft is also referred to as 'Hollsmidt'. During construction the covering was changed from fabric to glued-on aluminum sheets, at that time a rather advanced method, to provide smoother roundings.
Powered by two converted VW 1200 car engines, the aircraft was first flown on April 24, 1964, with Harald Thyregod at the controls. The first five years the HT-l flew unregistered by dispensation from the Danish CAA but in 1969 it got its CofA and was registered OY-FAI. Except for test flying the aircraft has been flown exclusively by Arne Hollænder and mostly in the region of his farm. In 1978 the aircraft was donated to the Dansk Veteranflysamling (Danish Vintage Aircraft Collection) at Stauning and was occasionally flown till it was deregistered in 1987."