by Robert Dorning

The Röger hook

The protracted 3000 hour life extension inspection and type upgrade of the Club's LS-7 has been completed. At the time of writing XJJ is waiting to have its evaluation flight and then it will be available again for members to fly.

XJJ has had a type upgrade from a LS-7 to a LS-7WL. The WL stands for winglet. As part of this type upgrade a number of changes had to be made with the obvious ones being the replacement of XJJ's old winglets with factory supplied winglets and the installation of a Röger hook on the rear of the canopy frame. It is this Röger hook that is the subject of this notice to pilots and instructors.

The Röger hook is a device to ensure that when the canopy is jettisoned in flight, the canopy will be caught by the airstream at the front and will be lifted upwards before safely being carried away by the airstream. The Röger hook is a clip which holds the rear of the canopy frame in place so the front of the canopy will be rotated upwards by the airstream before the canopy breaks away. The photo shows the Röger hook mounted on the rear of the canopy frame.

The purpose of this notice is to alert pilots and instructors about the Röger hook as there is now the potential to damage the canopy when opening it normally. To open the canopy now, it is necessary have the canopy completely down (but handles unlocked), then apply a quick jerk upwards to the red handle on the left side of the canopy frame (after each handle has been opened to a right angle to the canopy frame). If the upwards jerk is applied to the red handle, damage won't be done to the canopy. However, if the jerk is applied to the top edge of the clear-view opening there is the potential the canopy will be cracked. This is most likely to happen when opening the canopy from the outside. Needless to say cracking of the perspex will lead to an unsightly repair to the canopy or a very expensive (around $7000) replacement of the canopy. When you are in the cockpit on the ground and want to open the canopy, use both red canopy handles.

Note, if the canopy is up and resting on the Röger hook stop, you cannot open the canopy, so the canopy must be all the way down before you jerk the canopy up by the red handle(s).

We ask instructors and LS-7 pilots to pay close attention to the new way of opening the canopy of XJJ in coming months and to help each other in becoming used to the new way of opening the canopy. Also we ask instructors to make a short briefing on the Röger hook a part of the conversion process for new pilots to XJJ. XJJ is the only Club single seater with a Röger hook.

The method of jettisoning the canopy remains unchanged - pull both red handles back, and the right hand red handle back past the normal opening position until the canopy springs free at the front.