The Viale Enrico Forlanini is a long street located in Milan, Lombardy, Italy.
 It cuts through a park, connecting the city centre with the Linate Airport and the Idroscalo lake.
 The street is named after Milan-born aviation pioneer Enrico Forlanini (1848–1930).
 However, it was originally named after Michele Bianchi (1883–1930) of the National Fascist Party.
Enrico Zeno Bernardi (Verona, 20 May 1841 – Turin, 21 February 1919) was an Italian engineer and one of the Italian automobile pioneers.
 As a child growing up in Verona, Bernardi spent much of his free time in blacksmiths' workshops learning the skills to put his inventive abilities into practice.
 In 1856, he entered a mechanical model of a steam engine and locomotive in the Verona Agricultural Exhibition, where he earned an honorable mention for his work.
Enrico Mosconi (1843-1910) was an Italian engineer, father of the General Enrique Mosconi.
 He had active participation in construction of the railways in the Argentine Republic.
An airship or dirigible balloon is a type of aerostat or lighter-than-air aircraft that can navigate through the air under its own power.
 Aerostats gain their lift from large gas bags filled with a lifting gas that is less dense than the surrounding air.
Carlo Forlanini (11 June 1847 – 26 May 1918) was an Italian physician.
 He was the elder brother of aviation pioneer Enrico Forlanini.
Enrico Volterra (11 June 1905, Rome – 29 June 1973) was an Italian engineer.
Enrico Mazzanti (5 April 1850, in Florence - 3 September 1910) was an Italian engineer and cartoonist, who illustrated the first edition of "Pinocchio".
This is a complete list of Forlanini airships designed and built by the Italian pioneer Enrico Forlanini from 1900 to 1931 (posthumously).
 These, like the German Groß-Basenach semi-rigid airships, were the first to have the gondola attached to the envelope, to reduce air resistance.
Enrico Forlanini (13 December 1848 – 9 October 1930) was an Italian engineer, inventor and aeronautical pioneer, known for his works on helicopters, aircraft, hydrofoils and dirigibles.
 He was born in Milan.
 His older brother Carlo Forlanini was a physician.
Enrico Benzing (born June 17, 1932) is an Italian engineer and journalist, son of the writer Mario Benzing.

Question: What type of aircraft did the Italian engineer Enrico Forlanini work on that was an aerostat?
Answer: airship