"equal speed" is a grammatically correct phrase and can be used in written English.
It is often used to describe a situation in which two or more objects or people are moving at the same pace or rate. Example: "In a race, both runners were moving at equal speed, making it impossible to determine who would cross the finish line first."
They're going up and coming down at about equal speed.
Hits and misses are shoved down the timeline at equal speed, so comedians can always start over.
He had suddenly shot into the firmament under Truman and Acheson; and then, like a comet, with equal speed he disappeared off into the outer darkness.
And with equal speed a new kind of conductor emerged -- part scholar, part entrepreneur -- to meet the unaccustomed demands of old repertory with new performing groups.
"There is in the trivial things of life, in the daily changing of external things," wrote Baudelaire, "a speed of movement that imposes upon the artist an equal speed of execution".
If you type in the domain name of a large corporation or a small blog, a government Web site or a radical political party, the pages are sent to your computer with equal speed.
Residential connections typically send and receive data at equal speeds.
As money comes and goes at equal speeds, administrators can easily play puppeteer with the numbers.
The announcers talk about sprinters needing the strength to finish the last forty metres, as though all-out sprints at equal speeds aren't something we've done since age five.
His method of determining that the births, at different locations, were simultaneous was to have a messenger leave each birth site at the moment of birth and travel to the other, presumably with equal speeds.
At lower gas preheats, the waves were observed to emanate from a single stationary point on the wire, travelling with equal speeds in both directions away from the source.
