how many times do rotor blades of helicopters revolve per second ?

Answer 1

As a general statement, the tip speed of a vertol (vertical take-off and landing) aircraft is around 80 mph or 128 kmh.

This translates into rotor speeds of 225-300 rpm for most private and commercial helipcopters ... whose rotor "circles" are 45 to 60 feet in diameter.

Since there are 60 seconds in a minute, this means rotor speeds of 3.75-5.00 revolutions-per-second.

There are some military craft that exceed this criteria, but not by very much. The highest rotor speed (that I know of) is 325 rpm, which equates to 5.42 rev-per-sec. The slowest speed is 200 rpm, or 3.33 rev-per-sec.

I've been lucky enough to be one of the test stand designers for helicopters several times over the last fifteen years or so.

Also note: the BLADE speed is much reduced compared to the ENGINE SHAFT speed; engine shafts may be turning in the 22000-40000 rpm range, but the blades are doing only 225-250 rpm (a gear reduction of more than 100:1)!

Answer 2

It depends on many things. (Like number of the blades in rotor) But far as I know helicopters main rotor spins around 200 - 400 times per minute.. So that makes..

300rpm / 60s = 5r/sec

Does this help?

Answer 3

At one point in time, the blade will be aligned with the nose of the helicopter, and a tenth of a second later, that same blade will be aligned with the tail.

Answer 4

I cant tell ya per second but when I worked on UH1 hueys the primary rotaion speed was 33000 rpm at 33000 rpm the chopper would dang near take off without pulling up on the collective stick.LOL! Its been along time since I worked on one but I bet I could still fly it like yesterday