Long Ez Nose Job - Extended Nose
LONG EZ NOSE JOB - EXTENDED NOSE
I built my EZ almost 20 years ago. During this time period, ANY changes to the plans were considered sacrilege and you were going to crash, burn, and live in hell for eternity. (Yah, Whatever)
A secret message was passed around to all those who were still “Closet Modifiers”, if you’re installing a larger engine you needed to extend the nose, move the battery forward, and do a couple things to the motor mount and extrusions. Ok, sounds good, but how do you do this?
This is the way I did mine!
Here are my thoughts on extending the nose:
1) Nose Bumper. The bottom curve of the nose needs to take into account the nose bumper. If you look at the finished photos of my nose, note that the top surface doesn't "curve" down, but is fairly straight (slanted down, not curved down). The bottom surface curves up, fairly sharply.
If the bottom is not curved upward to take into account parking in the nose, the nose will rest on the pitot tube when parked.
This "upward" curve of the bottom surface will limit how far the nose can be extended, yet maintain a nice aerodynamic shape
2) Battery weight. During a 5 G maneuver, a 25 lb battery weighs now weighs 125 lbs.
The original nose and NG30s helps transfer loads from NG30 (nose gear mount bulkheads) back into the main fuselage via NG22 and the actual nose. I wanted to make sure that I didn't detract from this load transfer process.
When I built my NG30s, I made them a couple inches taller to take into account a more gradual curving of the top surface. I also extended the bottoms of the NG30s, approximately 9 inches forward of where the nose gear bearing attach to the NG30s. This extension provided a "shelf" that the battery would rest on. I then added two bulkheads to the NG30 to form a "Battery Box" forward of the nose gear.
3) The Skid plate.
Just in front of the nose pivot bearings, I installed a 1/4 inch 2024 T3 plate. This plate is approximately 4 x 4 inches, and bridges across the bottom of the NG30. Any forces placed on the plate are transferred into the bottom of NG30. NG30 is notched in the bottom to accept this plate.
When the bottom of the nose is glassed, I laid up 6 layers of BID across the plate out onto the sides of the nose. The extra thickness helps transfer loads, but
The nose bumper is mounted to this plate by drilling a hole up through from the bottom, then tapping the hole to 1/4x24. In case of the inevitable nose up landing, the bumper , bolt, 6 layers of BID, quickly grind away. When the area is repaired, the area around the plate is sanded down to glass to provide a new bond. The reason for the 6 layers allows the extra glass for the re-bonding area to be sanded down without getting into structure.
4) CARVING THE NOSE
Lay in a pitot tube to mark the front center (the very tip of the nose) I used a piece of stainless tube that was pushed over the plans aluminum tube. The stainless will not bend and looks a little better.
Cover the NG30 with scrap pieces of urethane foam. Use a knife and 36 grit paper and carve away anything that doesn't look like a nose. If you get into the top of NG30 or into the battery box bulkheads, you need to evaluate if you should cut the bulkheads down OR rebuild the foam and re-carve to fit the existing bulkhead.
When finished carving, glass the exterior of the nose as per plans, (Add the extra layers of glass around the skid plate.)
5) NOSE COVER
Use a black marker and lay out the shape of your proposed cover on the top of the nose. (draw an outline of your cover)
Make sure you account for a ˝ inch lip all the way around the nose to mount the nut plates. (The cover will be larger that the opening by ˝ inch all the way around)
Cover the entire nose with plastic. This should be a good fit with no wrinkles on the top.
Lay up 4 or 5 layers of BID on a flat surface. The lay-ups should be larger than your proposed cover. Pick up the lay-ups and drape them over the nose. Double check that the lay-ups are laying flat against the nose. (Vacuum is OK)
After cure, pop the cover off and cut it to its final shape.
6) CARVING THE INSIDE
NOTE, Make the cover before you cut holes to carve out the inside of the nose.
Cut the openings in the top of the nose.
The inside of the nose can then be carved out and glassed as per plans.
F16 performance on a Piper Cub budget
LongEZ, 160hp, MT CS Prop, Downdraft cooling, Full retract
Last edited by Waiter : 07-06-2007 at 10:57 AM.
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