Richard Ashworth

I could see the same problem before I started on the tray but dealt with as follows. I cut out a section of the lower cowl, Dremel milling cylinder, rounded corners slightly wider than tray but not as wide as removable hatch cover which slips in about 5mm under the back edge of the uncut cowl sides and will stop it coming out if it ever came loose in flight. This allows the battery on a sled strapped on with insulation tape, to go in as parallel to the tray as possible. Overlander 4s 4250 depth 34, width 41, length 133 easy fit, but for progression to 5s 41,41,133 I have shaved a couple or mms off the former over the tray, mid battery. Clearance checked by trying to install the 4s on its side. 6 trouble free flights so far, the 50mm wide, 20 mm deep opening left when the hatch cover is in place seems to allow more cooling air in as the battery has come out of the plane stone cold after all flights so far, the opening in the underneath behind the wing will prevent pressure build up inside the fuz. Other than that everything went together as per the instructions and a bit of thinking before each step (1st make, all bolt together foamies previously). Only non instruction work needed, 3 hours with covering iron sticking everything down, 2 hrs before first flight then another hour after it sat in sun and every bit not already smoothed, shrunk etc bubbled or went slack! Be prepared!