Why does a car in reverse sound so whiny when no other gear does?

Question

I saw a brand new ’69 plate car reversing today and it still made that noise so it can’t be attributed to an old gearbox

In: Engineering

Answer 1

In addition to what the others have said, the reason that reverse gears are straight cut is that they have to slide past each other in order to engage reverse. This is not possible with herringbone or helical gears. The forward gears are constantly meshed so don’t need to slide past each other.