Poniżej dokładniejsze dane. I można przyjąć , że to był efektywnie naukowy przelot (brak doniesień , że było inaczej).
The probes set a maximum speed record for spacecraft of 157,078 mph (70,220 m/s). Helios-B flew 3,000,000 kilometres (1,900,000 mi) closer to the Sun than Helios-A, achieving perihelion on April 17, 1976, at a record distance of 43.432 million km (26,987,000 mi; 0.29032 AU)
https://en.wikipedia.org/wiki/Helios_(spacecraft)
https://solarsystem.nasa.gov/missions/helios-2/in-depth/Data was obtained about the velocity and distribution of the solar wind , the intensity of the solar magnetic field and distribution of cosmic rays . Energy transported in the solar wind was found to be carried by protons . Measurements from Helios showed the solar wind has two main velocities . When the wind speed is high , the proton density is relatively low . When the wind speed is low the proton density is high . In the high-speed wind , heavier particles also have a higher temperature ; but is it the other way around in the slow wind , where lighter particles are hotter .
https://books.google.pl/books?id=Ud2icgujz0wC&pg=PA37&redir_esc=y#v=onepage&q&f=falseThe Helios mission consisted of two spacecraft that were used to make in-situ observations of the inner heliosphere. Helios 1 was launched on December 10, 1974, and Helios 2 on January 15, 1976. The orbits of the Helios 1 and 2 spacecraft had periods of 190 and 187 days, aphelia of 0.99 and 0.98 AU, and perihelia of 0.31 and 0.29 AU, respectively.
In terms of design and instrumentation, the two spacecraft were nearly identical; each was equipped with several instruments,two booms and a 32-m electric dipole antenna. Each spacecraft spun once per second about an axis normal to the ecliptic plane. Operations ceased for Helios 2 on March 21, 1980, and for Helios 1 in March of 1986. (...)
http://helios-data.ssl.berkeley.edu/about/Both probes operated in tandem and supplied plenty of data from a variety of positions. Additional findings could be extrapolated by comparing data because the experimental apparatus on each probe was virtually identical. Contrary to expectations, the probes survived the hellish conditions without damage and still sent data to the earth even ten years later. They are still orbiting the sun today. It takes about 190 days for them to complete one orbit around the sun.
https://www.deutsches-museum.de/en/collections/transport/astronautics/satellites/helios-probe/