As well as protecting the external surfaces of an aircrafts structure,attention has to be given to the hidden interior,metal aircraft in particular go through a lot of climatic changes which if unchecked can cause all sorts of corrosion and degradation of the structure,in particular where unlike metals such as magnesium castings are in contact with alloy or steel materials this can quickly accelerate into a white powder which is such signs that there are problems,to avoid this a thin layer of yellow chromate paste is applied to the mating surfaces.Zinc chromate is a major factor in preventing corrosion,when you next look into the wheel bays of an aircraft at your local air museum take a closer look,you will probably see a matt pale yellow colour somewhere or another,this is a zinc coating that is sprayed onto the metal when the aircraft is first built,it must be checked and maintained to ensure the surfaces are free from corrosive air and chemicals that will attack the airframe,furthermore it is applied together with a weak acid,this is usually a selenious material which will etch gently into the metal,the colour can vary between different countries,the U.S Air Force tend to use a slightly greenish tinge but the idea is the same,ie to protect metal during the life of the aircraft.
During WW2 a finish was developed by Titanine aircraft finishes,that made the interior cockpit colour of the aircraft easy on the eyes,especially when map reading or when conditions were poor,it is generally termed and known as 'cockpit green' a pale shade of green,this can still be seen today in many preserved vintage training aircraft of that period,it was made in both synthetic and cellulose finishes,the former tending to be more glossy and the latter a semi-matt finish.Instrument panels were normally black,once again a semi matt finish and normally bombers had a black finished quadrant and other fittings.Another finish that must be mentioned is a material called Lanolin,this again is a fine anti corrosive material usually used in difficult areas where paint would chip off,lanolin can be poured into aircraft tubuler structures and plugs placed into the ends,it is there for the life of the aircraft,the colour varies but normally it is a burgundy type of red in shade,it can also be painted onto fittings,the main advantage is that it never fully dries out and exhibits excellent anti corrosive properties even in salt air,this is why it has been used in many Naval aircraft over the years.
This is only a small insight into what happens inside an aircrafts structure and the materials used,by explaining the above in simple terms gives the scale modeller a better understanding of what the interior of any aircraft in service looks like,after all not many people get that chance to look beyond the exterior finish of any machine.
Inside a B-17 Flying Fortress,this shows to good advantage the chromate green colour used during the WW2 period and beyond.Note even then the different shades of finish used on this particular aircraft.
During WW2 a finish was developed by Titanine aircraft finishes,that made the interior cockpit colour of the aircraft easy on the eyes,especially when map reading or when conditions were poor,it is generally termed and known as 'cockpit green' a pale shade of green,this can still be seen today in many preserved vintage training aircraft of that period,it was made in both synthetic and cellulose finishes,the former tending to be more glossy and the latter a semi-matt finish.Instrument panels were normally black,once again a semi matt finish and normally bombers had a black finished quadrant and other fittings.Another finish that must be mentioned is a material called Lanolin,this again is a fine anti corrosive material usually used in difficult areas where paint would chip off,lanolin can be poured into aircraft tubuler structures and plugs placed into the ends,it is there for the life of the aircraft,the colour varies but normally it is a burgundy type of red in shade,it can also be painted onto fittings,the main advantage is that it never fully dries out and exhibits excellent anti corrosive properties even in salt air,this is why it has been used in many Naval aircraft over the years.
This is only a small insight into what happens inside an aircrafts structure and the materials used,by explaining the above in simple terms gives the scale modeller a better understanding of what the interior of any aircraft in service looks like,after all not many people get that chance to look beyond the exterior finish of any machine.
Inside a B-17 Flying Fortress,this shows to good advantage the chromate green colour used during the WW2 period and beyond.Note even then the different shades of finish used on this particular aircraft.
Comment