[1] Wind tunnel testing showed promise, but the Bo 46 demonstrated a number of problems and added complexity that led to the concept being abandoned.

The reason the blades are adjusted in the front and back instead of right and left is due to phase lag caused by precession.

These were in addition to the system used to change the angle of attack to provide control; rotor hubs tended to be very complex.

From an elementary aeronautical point of view, there exists two main problems regarding the maximum airspeed of a helicopter as imposed by its rotor system.

The inherent flight mechanics of a helicopter not at hover will result in a portion of the rotating blade disk to "see" a lower airspeed relative to the direction of travel.

One solution to this problem is to increase the rotor rpm so that the relative airspeed of the retreating blades are higher.

Airfoils designed for subsonic flight will experience a significant increase in drag if they are subjected to transonic or higher airspeeds.

The basic problem inherent in rotor design is the difference in airspeed for the advancing and retreating blades.

Among the many effects this causes is one of interest; the blades rotate forward and backward around the hub as drag increases and decreases.

Since the motion in the Derschmidt rotor follows the natural change in drag through the rotation, the force applied to the blades to move them into position is quite small.

These rods were attached to a disk set eccentrically to the centre of rotation, which drove the blades into their proper locations.

[2] Last in the series of designs was a different approach that used a single counterweight for each blade, geared so its motion was mechanically amplified.

There was no mechanical attachment between the blades, and the entire assembly sat outside the hub, leaving ample room for maintenance.

[2] Bölkow had been interested in high-speed rotor flight for some time, and had drawn up several experimental concepts based on tip jet systems.

[4] Adding separate engines for additional forward thrust was expected to allow speeds as high as 700 km/h (380 kn).

This design would be powered by two T55 or T64 engines, each of which drove both a Derschmidt rotor and a forward-facing propeller for additional forward thrust.

In testing a series of unexpected new types of dynamic loads were encountered, which led to dangerous oscillations in the rotor.