The access hatch and spine piece
An access hatch atop your mugi will allow easy access to your radio gear and also make swapping flight batteries a very quick task. The Mugi Evo is designed for an eight-cell standard battery pack or high performance Lipoly pack, some of which tend to be quite large, making this feature practically essential.
The hatch is built into the 'spine' of the aircraft. The spine is a strengthening piece that runs down the back of the airframe with its flute direction spanwise to provide the greatest rigidity against the in-flight forces that would try to fold the Evo wing in half.
Fitting the hatch
You should have now cut out the hatch/spine piece according to the instructions on the plans page. Lay the spine in place from the rear of your exo doubler down the top of the airframe. At this time you can trim the spine to fit widthwise with your exo doubler and also for length so that it does not extend beyond the rearmost point of the Evo's tail.
Mark the position of the piece lightly on the top of your airframe and then apply the contact adhesive - be sure not to glue the hinged hatch panels!
When the glue is ready to bond, firmly stick the spine in place (as in diagram 2 above) and then open the hatch to reveal the wing below.
You can now cut out the wing material directly below the hatch to grant access to the inside of your aircraft (as diagram 3 above).
For flight, the hatch can be taped down for security before launch. Tape is a cheap and painless solution to preventing the hatch from opening in flight.