Inspecting Aircraft Paint

At first glance, your new paint job looks beautiful. As you take a closer look there appears to be minor defects that occurred during the process. Streaks, runs, specks and dirt in the paint are unfortunate. Some can be corrected with carful grooming and polishing. Preventing these minor mishaps, the paint shop needs to washed and clean prior to the final coat being applied. Also the experience of the painter and the touch of the application is the key to a successful paint job.

“Runs” in the paint are due to an application that is too heavy. Small runs can be carefully shaved and then polished. Even for the best painters this is difficult and runs can be seen even after buffing. Large runs cannot be corrected and will result in large areas being stripped and re-panted. “Rag Marks” are due to residual solvents left on the fuselage during preparation looking like wiped streaks. The vapors get trapped beneath the paint and can cause the finish to bubble and blister. In some cases these areas can be polished and buffed out.    

Fish Eyes

“Fish Eyes” occur when dust and dirt in the paint area get caught the stream of paint during application. At 40 PSI they are then shot back into the paint creating what appear to be small creators in the finished surface. Fish eyes can be shaved or lightly sanded out and then with a fine airbrush can be touched up, then buffed out and polished. If they occur in a white finish they a heard to find, but if the occur on a dark painted finish they will look like spot marks or blemishes in the finish.

Orange Peel

“Orange Peel” is an effect due to an inconsistent mix of paint and air being applied. The surface looks pebbled and lacks a high gloss finish. Minor orange peel can be polished and buffed, but large areas are difficult and will typically look worse than before. There are also areas where paint is applied to thin or to thick. These conditions area again credited to the painter and their experience in painting business aircraft.

No paint facility wants to spend the time or money re-painting your aircraft, so they are always confident that these minor issues can be corrected. In some case the can be, but in many the simply cannot. Polishing and buffing can repair minimal defects but if they are significant they will not be able to remedy these areas. Over buffing can cause burn marks and visible swirls in the paints finish. A properly applied paint job with a Teflon protective coating should last between five to eight years and is dependent on whether the aircraft is hanger kept or not.

Paint Livery & Design

Ramp image has long been a driver of exterior paint designs for VIP and business jet aircraft. Much of this is driven by the jet’s ownership on how much or little of a statement they choose to make. Most prefer to go unnoticed with paparazzi sitting just of the edge of airports posting pictures on the Web. Some companies may use it as a marketing tool like Nike’s sneaker, Oakley’s camouflage or New Yorker’s jeans branding. Additionally, once unheard of using the corporate logo is now being seen on exteriors is a common sight today. This all depends on the company’s position, marketing strategy and in some cases aircraft and passenger security.

In addition to unique designs and logos is the use of national flags, unless required by regulatory authorities. This is dependent on the countries you operate in or fly into. We all know that N means US, but to the general public it means little unless a US flag is painted on the tail.

Complex designs and multi-color schemes raise the cost of painting an aircraft. Each additional color requires the shop to mask the aircraft and paint new colors that can add time in the painting process. There is also the consideration of metallic and multi-directional paints that change color from the viewing angle. The aircraft’s belly or upper can be painted a contrasting color. When considering painting the wings keep in mind that dark contrasting colors on the top of the wing will conduct heat and can affect fueling in hot weather conditions

Superjet Paint Concept

Most paint facilities can provide you with numerous design renderings in both 2D and 3D to assist in making your decision. If it is hard to visualize these, you can go as far as to have a desk-top mode of your aircraft painted in the new livery to confirm your decision. Spend enough time on the design phase as you may need, because you will live with your choice for a very long time.     

Aircraft Painting – Strip & Prep

A successful aircraft paint job begins with the surface preparation. A new aircraft from the OEM needs only to be lightly sanded and cleaned prior to receiving the primer-filler coat. Some rivets may need to slightly shaved if they don’t properly sit flush to the skin. Temporary seals need to be cut out and removed while others need to be covered with tape. The quality of skin work varies and can be flushed with body fill, however over time this putty can crack loose so use it very sparingly or none at all.

Repainting an existing aircraft first shall require the stripping of the old paint. This will first be dictated on the shop’s location and its use of chemical strippers. The Environmental Protection Agency (EPA) in the US has regulated the use of toxic strippers that contain methylene chloride. Older facilities can still use these strippers but must contain the waste in drums and have it removed by collection systems. Newer facilities or some that has changed for environmental concern, now use synthetic polymer beads and high pressure air systems that simply blast away the old paint without penetrating the aluminum skin. This technique is similar to sand blasting where a pressurized gun blows beads against the airframe at about 40 PSI. The beads, dust and paint is removed in a prep-area and then the surface is lightly sanded as required and cleaned for priming and painting.

The use of bead blasting also has its advantages where chemical etchants can get between aluminum panels and rivets where the OEM has sealed theses seems where Alodine was used to prevent corrosion. Strippers can also affect the coatings and anodized finishes of fasteners and rivets. It would be a good idea to consult with the OEM by speaking to your local in-field, service representative before you strip you aircraft.

Once the paint has been removed, inspect the surface carefully to be sure all of the old paint has been removed and that there is no residue, oils or hydrologic fluids on the skin surface. Also dust or dirt needs to be wiped off as any of these contaminants under the primed or final paint finish will affect the longevity and durability of the final painted surface. All of the foil and paper protection from the stripping process now needs to be removed and replaced with new protection to begin the paint process staring with the primer coat.