When the Gotthard Basis Tunnel was placed into service, the Swiss Federal Railways (SBB) announced internationally in the spring of 2012 the delivery of powered rail car trains with a maximum speed of 250 km/h / 156 mph. Eventually, the Swiss firm Stadler prevailed in April of 2014 with their concept SMILE (Schneller Mehrsystemfähiger Innovativer Leichter Expresszug / Fast Multisystem Innovative Lightweight Express Train), whereby Stadler built a high-speed train for the first time. The SBB ordered 29 eleven-part units of the new class RABe 501 for international service and assigned them the designation "Giruno" (derived from Rhaeto-Romanic "girùn" for "Buzzard"). The trains can run in four countries under three current systems (15 kilovolts / 16.7 Hertz; 25 kilovolts / 50 Hertz, and 3 kilovolts DC) and are equipped with the ETCS, PZB, LZB, and SCMT train safety systems for this.
The "Giruno" is a 202 meter / 656 foot 6 inch long, single-level operationally permanent multi-unit train with Jakobs trucks. Only the end cars have normal trucks under their outer ends. Four Jakobs trucks are powered with three-phase, asynchronous motors, whereby the propulsion equipment is designed to be redundant with four traction rectifiers. An eleven-part class RABe 501 consists of four cars, 1st class, with 117 seats mostly in a 2+1 arrangement, a dining car, as well as six cars, 2nd class, with 288 seats in a 2+2- arrangement. The dining car as well as the two adjoining cars are constructed to meet handicapped requirements in order to satisfy the provisions of the Swiss handicapped access law. The "Giruno" has step-less entries for station platform heights of 55 cm / 22" and 76 cm / 30". Its pressure-resistant and air conditioned passenger areas and cab as well as the multifunction compartments and bicycle compartments in the passenger area set a new standard for comfortable travel by train. All of the passengers have a free view of the screens for the digital information system. In addition, cell phone signal boosters and WLAN are available in both classes.
On May 10, 2021, the SBB took delivery of the last 29 trains. Since then they have TSI permission as well as network permission for Switzerland, Germany, Italy, and Austria. Since December of 2019, they have run on regular schedules through the Gotthard Basis Tunnel and they connect Basle/Zürich with Chiasso and Lugano. Continuing runs to Italy to Milan started on August 12, 2020, since September in multiple unit operation too. In the next step, runs between Basle and Frankfurt/Main are planned. Also being considered by the SBB is the use of these new powered rail car trains in the direction of Hamburg.