Nothing wrong with understating your assets. If they have an aircraft on their books at 40m cost but the actual market value is 45m then there isn't an issue is there. RYR are quid's in and will make a 5m profit on disposal if they sell it. This is my point. The time to worry as an investor is when a company starts using a depn policy that writes off the asset over an unrealistically long period to reduce the annual hit on their P & L and thus resulting in an artificially high profit figure. The first tell tell sign of this would be when a PLC publishes its EOY accounts (which it is legally bound to do) and all of a sudden it turns out that the company has disposed off some assets in the year and made a massive loss on disposal. Infact, the tax man will then come knocking to ask whats been going on. Because companies are taxed on profit HMRC monitors yearly trends and would want to know why they are all of a sudden making such a big loss.