Some interesting observations above. Considerations -
(a) CAO 100.7 requires that an LDS change be made if the accumulated weight and balance data has varied outside prescribed limits. Whether this requires a reweigh or can be done by calcs is up to the WCO and this would be expected to be based on historical evidence of how much paint goes onto a particular sort of paint scheme.
Generally, a major paint job is done in association with other maintenance so it would be reasonable to do a good clean up on the aircraft. Whether the weight will go up or down depends on the delta between what comes out (dirt, rubbish etc.), what comes off (I've seen more than a few paint jobs over paint jobs over paint jobs), and what goes on (the current paint job).
My preference always is to reweigh .. not a major cost in the overall scheme of things and can result in an advantage to the operator. For instance, I can recall a DC3, years ago, which went down several hundred pounds after a good cleanout .. and repaint.
(b) CASA ought not to be involved at all in the normal course of things .. unless the repaint is associated with a significant mod program involving CASA airworthiness oversight.
(c) There is a rule somewhere too about how only a certain percentage of the aircraft can be coloured beyond that of the factory specification, eg 10%.
Never came across that one .. might be in the realm of OWT ?
(d) There have been many occasions when aircraft / operators have been penalised for too much colour on their aircraft but you usually only hear this offence tacked on behind a string of others.
I think that we'd all love to have you cite some specific examples of this one ?
(e) Last I heard you were meant to reweigh after any paint job?
Generally a good gameplan but not "required", per se. However, the WCO would need to justify the calculations in lieu of a reweigh.
(f) LAME's that aren't also a WCA are only able to approve very very minor changes in weight.
The non-WCO LAME can update the RWA data sheet within the LDS reissue limits. When the limit is reached and the LDS requires revision, that approval requires a WCO.
(g) I only know about it as we sold an aircraft a couple of years back which had extra stickers/decals applied and the company agent removed them as they were in breach of the regs because there was more than ~10% colour added. (or whatever the figure was)
Again, a pity you didn't ask him to cite the particular regs ?
(h) CASA took an operator up north to task that their aircraft were fitted with decals that weren't approved by CASA
advertising or confusion with the registration marks, most likely.
(i) Decals may also be different because you'd have to consider what effect they may have if they peel back.
Most of us would view decals in the nature of a mod requiring a CAR 35 tick in the box. Decal loss happens occasionally but, generally, isn't a problem (down the gullet may be a problem, however).
(j) as the paint required to make up the clours they wanted would have put a load of weight on the aircraft.
Then one either accommodates the weight penalty or changes the colour scheme.
(k) AA satrted to fly with a all metal to save on fuel
I recall reading a long time ago that the AA alloy paint scheme was driven principally by weight savings.