The Stops and Props check was carried out by the Flight Engineer before take off to ensure the prop pitch was working normally and the reverse stops were in position to stop uncommanded reverse. It was not possible to check the controls properly as they were not powered and were moved by small control tabs that did not become effective until about 80 knots. Hence both ailerons and both elevators were drooped during the initial part of the take off run.
The aileron tabs can be seen in this photo.
