Peel-n-stick Vinyl and polyurethane decals ['decalcomania'] have been used on MIL Acft for decades for stars/bars, letters, numbers, warning placards, paint replacement, etc.
I think Hill AFB [OC-ALC] has even tried full body decals on F-16s ILO Camo paint. The decals were installed in strip-segments for draping/nesting-together over complex curvatures. Unsure of results.
'How-To' ??? … this is our primary maintenance reference...
USAF T.O. 1-1-8 APPLICATION AND REMOVAL OF ORGANIC COATINGS, AEROSPACE AND NON-AEROSPACE EQUIPMENT
CHAPTER 7 - APPLICATION AND REMOVAL OF DECALS AND SILK SCREENING
Para 7.1 points to some VERY important application issues [restrictions/concerns]...
7.1 DECALS - GENERAL
NOTE
… ...
Decals are specially prepared plastic film containing designs,
words, numerals, or colored marking stripes, which may be
applied or attached to Air Force equipment as a method of
marking or identification. Decals can be used in lieu of paint
for internal and external markings and insignia as authorized
in Chapter 8. Decals shall conform to CID A-A-59485 or
commercial equivalent and are available in solid or perforated
film. Decals with perforations shall only be applied
over fully painted surfaces. For application to pressurized
areas on aircraft exteriors, prepared (factory) perforated film
shall be used to prevent blistering due to leaking rivets,
seams, etc. Non-perforated, premasked decals may be applied
directly to the primer prior to applying the topcoat.
Decals applied prior to the topcoat must be premasked with
low tack translucent application/mask tape, leaving a 1/16
inch uncovered lip around the decal edge. This lip will allow
the topcoat paint to seal the edge of the decal, eliminating
the need for edge sealer. The mask is removed after the topcoat
paint is allowed to cure. Decals are not authorized on
unpainted surfaces.
Closing Comments/NOTES.
WORKMANSHIP is everything!
Decal edges must be sealed [special sealants or clear polyurethane paint] to prevent air/moisture peel-up.
Decal corners that are rounded are 'most peel resistant'.
Perforated decals MUST be installed over [epoxy] primed AND [polyurethane] top-coated surfaces. This layering provides necessary moisture/corrosion resistance and [Duhh] colored primer might be visible thru the perforation spots [very odd appearance]. Perforations allow pressurized air-leaks to bleed thru the decal and vent to the atmosphere... without forming a 'bubble'.
Non-perforated decals can be applied to epoxy primer. These decals must be perfectly smooth and remain air-bubble free [prick all trapped air bubbles with a pin and flatten]. Even small bubbles will tend to expand with altitude... and as the decal becomes brittle with low-pressure cold air/ozone... and eventual dust/sand/ice/rain/etc impacts... will eventually become worse and likely 'tear/peel'.
Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
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