Although the document dates from 2001, I found this “Airbus Performance Audit View” [sic] nonetheless fascinating:

https://www.cockpitseeker.com/wpcontent ... ations.pdf

Some worthwhile quotes from this Audit View –which I imagine is a recap of Airbus performance audit findings from the 1990s– follow below. Given the 2001 publication date, these audits must have covered mainly A300s and A310s and perhaps some young A320s and A330/A340s.

Bearing in mind that the quoted drag penalties are in 2001 US$; one would have to apply about a 65% general inflation markup to arrive at comparable 2022 US$. The US$ penalty computation also takes into account 2001 cost of fuel, manpower, etc so that the quoted cost penalties would likely have to be doubled at the very least for 2022 US$.

• Page 9: “…an outboard slat misrigging causes nearly US$ 11,000 penalty per aircraft per year…”

• Page 12: “…the worst [instance of absence of seals] penalty would result from a missing fairing and rubber seal at the fin/fuselage junction (US$ 3,500 [per aircraft per year]).”

• Page 16: “For a complete aircraft - in the worst case [of skin roughness/dirtiness] - the penalty can be as high as US$ 60,000 per aircraft per year”

• Page 17: “Simple dents also cause some fuel penalty which are not costly in terms of fuel consumption (US$ 100 per aircraft per year in the worst case) but are very expensive to repair.”

• Page 19: “external patches induce more drag, especially on the wing upper surface (US$640 [per aircraft per year]).”

• Etc.

There are also quantitative tables summarising the cost data for misrigging, absence of seals, missing parts, mismatched surfaces, door seal leakage, surface deterioration, skin dents, etc later on in the document as well plentiful photos of instances of drag deterioration on Airbus aircraft.

The cost of skin roughness and dirtiness is quite impressive, it must now be above USD +120,000 per aircraft per year in 2022 terms...cleanliness is not just a matter of image.

I wonder whether with the latest CFRP aircraft, aerodynamic performance deterioration is less, or much less marked...


Faro

The link to the document seek to be unreliable...to access the document, do a Google search with the terms "getting hands-on experience with aerodynamic deterioration"...the document is the pdf at the top of the resulting list of search finds...


Faro

The Douglas product AMM Aero Smoothness chapter used to measure the cabin window thickness. As they got thinner from repair and polishing, they would bulge into the airstream, adding to drag.