The Sell That Plane blog, which is focused on tips, tricks and tactics for selling an aircraft, has a useful post about getting rid of aircraft cabin odor which is well worth reading even if you aren’t trying to sell your aircraft.
The post began by noting the lack of air conditioning means you are sweating in those seats – either due to summer heat or perhaps because your flight has gone down to the minimums. Then there always the chance of a passenger loosing their lunch while flying with kids can make the aircraft cabin smell like a “typical minivan.”
Since smells can linger in fabrics, Sell That Plane suggests getting the most mild scented Fabreze to spray down the seats or carpets. Then buy a can of Ozium and spray it in the cabin, closing the door. After sitting overnight with both Fabreze and Ozium in the cabin, airplane cabin odor should be history.
For a more severe aircraft cabin smell issue, the Sell That Plane blog suggests wiping down all cabin surfaces, cleaning out any doors or seat pockets, vacuuming or steam cleaning the carpets (either by renting a machine or having a professional do it), steam cleaning the seats and filling the aircraft cabin with Ozium and just letting it sit awhile (Ozium also works good about an hour before any perspective buyer shows up to look at the aircraft). In other words, taking care of your aircraft cabin and any odor problem in it is no different than taking care of any similar problems in your vehicle.
Finally, the Sell That Plane blog notes that a professional aircraft cabin cleaning (at least in the USA) should not cost more than $75 while a can of Fabreze and Ozium won’t cost more than $20 – small prices to pay if you are trying to sell your aircraft or just don’t want it smelling like your first training aircraft!