Brightwork Polish at Lyon-Bron (LFLY)

What changes at Lyon-Bron between summer and winter?

Lyon-Bron sits at 659 feet above sea level, ten kilometres east of the city centre, with a single 1 820-metre runway oriented 16/34. The airport is operated by Aéroports de Lyon and has been entirely dedicated to business aviation since commercial traffic moved to Saint-Exupéry in 1975, making it France's third-busiest business-aviation field. Handling is provided by the airport's own business-aviation team through a dedicated terminal.

The Continental climate brings hot, dry summers and cold, damp winters. Summer heat bakes exhaust residue onto thrust-reverser cascades and nacelle skins, turning a light film into a baked crust that needs compound before polish. Winter condensation and road-salt spray from the apron accelerate oxidation on leading edges and inlet rings, especially after aircraft return from Alpine approaches where freezing levels sit below field elevation. We adjust compound grit and dwell time to match the season: finer grades and shorter cycles in summer when the metal is warm and responds quickly, coarser cuts in winter when cold-soaked aluminium is harder and oxide layers thicker.

The single runway and absence of slot coordination mean we can usually negotiate a stand for the full duration without pressure to reposition. That flexibility matters when brightwork on an ultra-long-range aircraft stretches into a third day.

Why does bare metal oxidise faster here than at coastal airports?

Lyon's position at the confluence of the Rhône and Saône creates a microclimate of high relative humidity without the steady breeze that sweeps coastal aprons. Moisture lingers on horizontal surfaces—wing leading edges, top cowl lips, stabiliser tips—and the lack of wind means dew sits longer each morning. Aluminium oxide forms within hours if the metal has lost its sealant, and the oxide layer thickens with every wet cycle until the surface looks chalky grey instead of silver.

Exhaust gas leaves a sooty film on nacelle interiors and thrust-reverser blocker doors; when that film absorbs moisture, it turns mildly acidic and etches into the aluminium. Inlet rings pick up brake dust and tyre rubber thrown by nosewheel spray during taxi, and the fine particles act as nucleation sites for corrosion. We see the effect most clearly on aircraft that sit for a week between legs: the brightwork that looked acceptable on arrival is visibly duller by the time the crew returns.

Polishing removes the oxide and contamination; sealant application afterward fills the microscopic valleys in the metal and gives water nothing to cling to. The combination holds a mirror finish for three to four months in this climate, compared to six weeks if we skip the sealant step.

How does Brightwork Polish at Lyon-Bron fit between charter legs?

Most operators schedule the work during a planned gap of two to three days, often while the cabin crew is away or when the aircraft returns from a positioning leg and the next charter is not yet confirmed. We coordinate with the handling agent to keep the aircraft on a stand with GPU access so we can run lights inside the cowlings and check our progress without starting the APU. The tech log stays with the captain or flight-department manager; we do not make entries, but we do photograph every surface before we start and again after sealant application, then send the set by email before the crew arrives for preflight.

If the schedule compresses, we can complete inlet rings, spinner and exhaust in a single long day, leaving leading edges for the next detail. That partial approach works when the aircraft is about to appear at an airshow or corporate event and the most visible surfaces need to shine. For a full polish—wings, horizontal stabiliser, all nacelle brightwork—we ask for three consecutive days and access to both sides of the aircraft without repositioning. The handling agent usually prefers that we finish in one visit rather than return a month later for the surfaces we skipped.

What do handlers expect when a third-party detailing crew works on their apron?

The Lyon-Bron business-aviation terminal operates the handling in-house, and their ground team expects us to check in at the operations desk before we cross airside, even when we hold our own annual passes. They want to know which stand we are working, how many people, whether we need a ladder towed to the aircraft or will bring our own, and what time we will finish each day so they can plan pushback or towing if another aircraft needs the stand.

We bring our own power for polishers and work lights; we do not ask for GPU time beyond what the handler has already allocated for avionics or cabin power. All waste—used compound, polishing pads, sealant wipes—goes into bags we carry off the apron at the end of each shift. If we need to move a ladder or stand while another aircraft is taxiing, we wait for the handler's signal rather than cross behind a moving jet. The apron is compact and busy, and the handling team runs a tight operation; respecting their rhythm means we are welcome back the next time an aircraft needs brightwork.

Which surfaces receive compound and which go straight to polish?

Wing and stabiliser leading edges almost always need compound first. These surfaces take the brunt of rain, insects and particulate during cruise, and even when the paint behind them is flawless, the bare-metal strip shows scratches, water spots and a hazy oxide layer. We start with a medium-cut compound on a foam pad, working in short passes parallel to the airflow, then step down to a fine compound before switching to polish. Inlet rings follow the same sequence if they have been neglected; fresh brightwork that was sealed within the past four months often needs only polish.

Exhaust surfaces and thrust-reverser cascades are different. Carbon deposits bond to hot metal, and a standard compound will not shift them. We use a dedicated exhaust cleaner—mildly alkaline, safe for aluminium—let it dwell for five minutes, agitate with a soft brush, then rinse before compounding. Spinners and nose-cone trim are usually the easiest: they see less contamination, and a single polish pass brings them to mirror finish.

After polishing, every treated surface receives a thin coat of sealant. We apply it with a microfibre applicator, let it haze for two minutes, then buff to clarity. The sealant cross-links over the next twelve hours, so we ask crews not to touch the brightwork or fly through rain until the aircraft has sat overnight.

What goes into the photo report after Brightwork Polish at Lyon-Bron?

We photograph each section of brightwork before we lay a hand on it, using natural light and a neutral angle so oxidation, staining and scratches are visible. Those images go into a 'before' folder. After polishing and sealant, we shoot the same surfaces from the same angles in the same light—usually late afternoon when the sun is low and reflections are sharpest—and those go into an 'after' folder. The two sets sit side by side in a PDF, labelled by surface: left wing leading edge, right engine inlet, APU exhaust, and so on.

We also note any areas where the metal was too pitted to restore to perfect mirror—leading-edge erosion from years of ice crystal impact, or deep corrosion around fasteners that would require stripping and replating to fix. The report states what we did and what we recommend for next time: whether the aircraft can go four months before the next polish or should come back in two. The handling agent receives a copy for their records, and we email the full set to the flight-department manager or chief pilot within twenty-four hours of finishing. If the crew wants to see progress mid-job, we send interim shots by text; some captains like to check that we are not compounding through the anodising or leaving swirl marks.