Aircraft Interiors - Notes from Oshkosh Forum presented by Oregon Aero\

By Jim and Heather Butcher (EAA Chapter 221)


*For seats, consider synthetics (as opposed to wool or leather) because of possible water damage.
*Use closed foam insulation.
*Reds and blues fade fastest, earth tones and greys are better from that perspective.
*Seat needs to support three areas. Lumbar, legs (thigh support) and the lower 1/3 of the skull.
*Ideal seat is 15" off the floor.
*Seat should be constructed of three densities of foam. The base should be 70 which is very hard. The middle should be 40. There should be a thin top foam layer of 20 density which is cosmetic, with a soft feel.
*The base (70) foam should be 1" thick. The middle (40) foam should be 1" - 2". The top (20) foam should be 1/2" to 1" thick.
*The angle between the seat back and bottom should be 105 degrees.
*For the lumbar support, cut the foam in a triangle 1½" thick, 13" high and width of the seat. Keep fitting to get the correct height and thickness. Glue in place.
*The thigh support should be 1" density 40, and it should roll over the front. It should just touch the back of the thighs, but not cause pressure.
*For the head support, make a roll at the neck and use 1" foam to cover and go over the back.
*Build up side supports.
*Will need to put rigging and rods in to keep the cushions in place using "pull in points". The fabric can be tied to these using buttons.
*Shoulder harness attachment should be able to withstand 9 times body weight. 15 degrees is the optimum angle from the shoulder to the attach point. 0 to 30 degrees is the maximum for the range. Can use a cable to pull back to a structural point, with 15 degrees to the first attach point, then a cable to the back of the plane.
*The seat belt should attach at a 45 degree angle and should have a strength of 12 times body weight.
*Need a commercial sewing machine to do the upholstery properly, with "walking foot needle feed". Sewing should be at 12 stitches per inch.
*Make paper patterns and fit them before cutting fabric.
*Sew on one side, turn over and sew again a second time with the second stitching just offset from (not on top of) the first. This will give a better fit.
*For side panels, make patterns out of "engineering paper" from an art supply store. It is actually a type of cardboard.
*Think about sections of panels so they are easier to fit in and out.
*Make patterns a little big and do the final trim in the aircraft.
*Make sure seats, cushions and panels fit properly and can come in and out of aircraft before upholstering. Mark any features (pleats, etc.) on foam.
*Rails, hold with velcro. Fabric and foam fit in rails. Tuck carpet into rail.
*1/8" closed cell urethane foam, glue ½" soft (20 density) to it. Stretch fabric over, sew velcro to it. Sew pattern in (lightweight cloth on back of foam).
*Plex canopy means the aircraft will not be too quiet.
*Head liners - one way is to use two wires. Sew canvas loops to the fabric and run wires through the loops. Other ways are hard or semi-rigid foam then stretch and glue fabric and roll over edges. Use 3M 8410 glue and spray it with a cheap spray gun. CAMI 300 is a temporary glue to put in foam then cut to fit. Start in center and stretch out. Or rods in bows.
*Wool is easiest material to use for headliners because it is stretchy and can shrink. Put boiling pot of water on a hot plate inside with the doors closed (water dripping down the windows) so that it will shrink and fit.
*Reinforce seat pans with ribs 2" apart for structural strength.


References:

Supplies www.skandiaupholsterysupplies.com

Technical information on conformal foam

www.earsc.com Click on Engineering, Technical, White Papers. There are two.

How to article www.eaa.org Go to members section, Homebuilts, Building, Cockpit cabin interior. Tony Bingelis article on building a seat.

General Reference: Oregon Aero Catalog pages 22 - 26 www.oregonaero.com/