Just a quick response to the topic that got locked, the A380 engineers determined that ice formation on the new "critical" wing was only noticable detrimental at the area where the #4 slat is located. Keeping this area only this area clean has proven to be successful.

I said this in the other thread but it got lost.Slat 4 was identified as being the most critical area of icing on the wing. The criticality is a measure of susceptibility to icing and also the impact of icing on the overall handling qualities (HQ) of the aircraft and in some cases the functionality of a part. An analysis is performed during the design and then the prototype aircraft is fitted with ice shapes and a series of HQ flights are performed. This will verify (or help refine) the design decisions. Once these tests are complete the aircraft carries out a natural icing flight test campaign (usually involves flying into storms if this happens to coincide with summer). This campaign will show how ice naturally forms over the wing and so the verification cycle would be more or less complete.In an ideal world the manufacturer would rather not de-ice the wing (it's all additional weight) so when anti-ice systems are found to be required they are only fitted where it is necessary for safe handling of the aircraft. Given the temperature of bleed air it is a safety risk in itself and to protect against that you end up adding even more weight.Andy

I don't see why they wouldn't want to put a anti-ice on the whole wing, its such a siimple way to keep the ice off, and it can be used endlessly.

Its just a simple heater on the leading edge that melts the ice, you know?

I don't see why they wouldn't want to put a anti-ice on the whole wing, its such a siimple way to keep the ice off, and it can be used endlessly.

Peter,Can't you read? The answer is just above your post (thanks to Allan and Andy) :1- Apparently, it was determined that the current minimum installation was necessary/sufficient2- Any system that is not necessary means un-needed cost, weight, complexity, energy consumption, maintenance... Hope this answers your question.Bruno

I know that, but this short-cutting of Airbus led to the Air France distaster, and their 'protective' programming led to the U.S Airways ditching.

Its just a simple heater on the leading edge that melts the ice, you know?

It is a little more complicated than that. In very basic terms, leading edges are heated using high stage compressor air (usually 15th or higher) routed to telescoping tubes with holes in them (nicknamed "piccolo" tubes) in the leading edges of the wings. Bleeding air off of an engine, especially at low power settings is quite taxing on the engine (stalls, higher fuel flow and EGT, etc.) and has a tendency to degrade its efficiency. With regard to the size of the wing on the A380, it would require a very high volume of air to be efficient, and that may be more than either available engine variant was able to expel without risking other factors, such as engine efficiency, degradation or even stalls due to airflow restrictions. This is one of the reasons that the 787 has electrically heated wing and engine leading edges. If you have no customer bleed demand off of an engine("customer" is a term used to describe what engine bleeds typically are used for like packs, anti ice, thrust reversers) then your fuel efficiency rises, and we all know how important that is today.

I know that, but this short-cutting of Airbus led to the Air France distaster, and their 'protective' programming led to the U.S Airways ditching.

Feeding time for trolls is over. Go eat your french fries in someone elses yard.