What are the repairs done to a wing spar?
The damage to the spar web can be repaired with a round or rectangular doubler. Damage smaller than 1-inch is typically repaired with a round doubler and larger damage is repaired with a rectangular doubler. Remove the damage and radius all corners to 0.5-inch. Fabricate doubler; use same material and thickness.
How many splices can you put in a spar?
Not more than two splices should be made in any one spar. When a satisfactory repair to a spar cannot be accomplished, the spar should be replaced. New spars may be obtained from the manufacturer or the holder of a PMA for that part.
What areas of a wood spar may not be spliced?
16. Which area of a wooden aircraft wing spar must not contain any splice? There must be no splice under wing-attach fittings, landing gear fittings, engine mount fittings, or lift and interplane strut fittings.
What is considered a major repair?
Major repairs involve large expenditures that extend the useful life of an asset. For example, the replacement of a building roof is considered a major repair if it allows the building to be used beyond its normal operating life.
What is considered a major repair or alteration?
Major Alteration: An alteration not listed in the aircraft, aircraft engine, or propeller specifications, that: Might appreciably affect weight, balance, structural strength, performance, powerplant operation, flight characteristics, or other qualities affecting airworthiness; or.
What are the types of the common wood spar?
Wooden spars are usually made from spruce. They can be generally classified into four different types by their crosssectional configuration. As shown in Figure 7, they may be (A) solid, (B) box shaped, (C) partly hollow, or (D) in the form of an I-beam. Lamination of solid wood spars is often used to increase strength.
How are reinforcement plates attached to a wooden spar?
Reinforcing plates are glued to both sides of the splice. Why must abrupt changes in the cross sectional area of a wooden structural member be avoided? Abrupt changes in the cross sectional area of a structural member concentrate stresses and can cause failure.
What is the correct repair to a wooden aircraft wing spar if the wing attach bolt holes in the spar are elongated?
What is the correct repair to a wooden aircraft wing spar if the wing-attach bolt holes in the spar are elongated? Splice in a new section of the spar and drill new holes.
Why should sandpaper never be used when preparing a scarf joint in a wing spar for splicing?
Why should sandpaper never be used when preparing a scarf joint in a wing spar for splicing? The dust caused by sanding will plug the pores of the wood so the glue cannot get in to form a good bond.
Whats considered a minor repair?
Minor repairs means the renewal or replacement of any existing part or parts of a building or structure, in keeping with its existing type of construction, arrangement of parts and occupancy for maintenance purposes, when the structural parts of the building or structure are not affected.
What is considered a minor repair?
Minor repair means routine work done to an existing structure, facility, use, land, and equipment, that involves mostly cosmetic work or like-to-like replacement of component parts, and that results in negligible change to or impact to land, or a natural and cultural resource.
What is classified as a major repair?
Major repairs involve large expenditures that extend the useful life of an asset. For example, the replacement of a building roof is considered a major repair if it allows the building to be used beyond its normal operating life. Or, the engine in a forklift is replaced, thereby extending the lifespan of the equipment.
What material are wing spars made of?
Currently, most manufactured aircraft have wing spars made of solid extruded aluminum or aluminum extrusions riveted together to form the spar. The increased use of composites and the combining of materials should make airmen vigilant for wings spars made from a variety of materials.
What is the purpose of a wing spar?
In a fixed-wing aircraft, the spar is often the main structural member of the wing, running spanwise at right angles (or thereabouts depending on wing sweep) to the fuselage. The spar carries flight loads and the weight of the wings while on the ground.
What are some common factors in premature glue deterioration include?
Some common factors in premature glue deterioration include:
- Chemical reactions of the glue caused by aging or moisture, extreme temperatures, or a combination of these factors.
- Mechanical forces caused mainly by wood shrinkage.
- Development of fungal growths.
What is the name of the glue for joining wood together?
Polyvinyl acetate (PVA)
Wood glue: The basics Polyvinyl acetate (PVA) glue is the most common type of wood glue. This type includes typical white and yellow glues, or what are commonly called “carpenter’s glue.” Iit can be used for many – but not all – projects.
How do you make wood joints stronger?
You can make the dowel joint by drilling holes completely through one piece of wood and into the other. Dowels are driven into these holes, completely through one piece of wood and deeply into the other. Then glue the dowels firmly into position to provide strength and prevent slippage.
What is the largest hole in a plywood wing skin that can be repaired with a fabric patch?
Cards
| Term WHICH SPECIES OF WOOD IS CONSIDERED TO BE THE STANDARD WHEN COMPARING OTHER WOODS FOR USE IN AIRCRAFT STRUCTURE? | Definition SITKA SPRUCE |
|---|---|
| Term WHAT IS THE LARGEST HOLE IN A PLYWOOD SKIN THAT CAN BE REPAIRED WITH A FABRIC PATCH? | Definition 1 INCH IN DIAMETER |
What are wing spars made of?
Wood wing spars are fabricated in various designs using solid wood, plywood, or a combination of the two. [Figure 7] Figure 7. Typical splice repair of solid rectangular spar
Do you repair or sell replacement wood spars?
Replacement Wood Spars for Aeronca, Citabria, Scout, Decathlons, Piper Cub J3 and Taylorcraft Not Only do we Repair,but we Sell these Great Aircraft ! Rainbow Flying Service specializes in the repairing rebuilding and maintenance of Citabria, Aeronca, Scout and Decathalon Aircraft.
How do you repair bolt holes in a spar?
In the case of elongated bolt holes in a spar or cracks in close proximity to the bolt holes, the repair may require a new section to be spliced in the spar, or replacement of the entire spar.
How do you repair a split wing splice?
The repair is reinforced on the side opposite the wing covering by a spruce block that extends beyond the scarf joint not less than three times the thickness of the strips being repaired. Reinforce the entire splice, including the spruce reinforcing block, on each side with a plywood side plate.