Brian,
I remember a recent, lengthy post on the FSM forum regarding this very issue - posted (I think) by Blackwolf3945…and I can’t find it…but I DO remember that it stated (and it quoted from official USAAF manuals, I think) that normally, the P-51B and C gear doors and gear bays were painted with green zinc chromate - and then later in the development process of the aircraft (the D models and later) the paint was deleted from these areas - so the doors and bays of the D were natural aluminum - but there was discussion about the main spar (visible from within the gear bays) as normally having been painted green zinc chromate.
I guess the long and short of it said that for the D model, the gear doors were not painted, and the gear bays were sometimes painted - but often left unpainted - but it also said that sometimes everything was painted, and it was best to check your references for that particular airframe (!!) - possibly a fairly difficult job depending on the airframe you want to model.
But I’d leave the doors unpainted, and paint the bays.
I have to disagree Brian. Mustangs left the facrtory with NMF gear bays and inner door surfaces. The main spar, at the back of the well was painted zinc chromate yellow. This is evident in color photos. The color NMF may have been silver, for lack of a better term, lacquer. Colors may have been changed when major maintenance or touch up painting was performed in theater. Joe
Not sure if this is important in this conversation or not but, my understanding is that on North American aircraft (the company not the continent) the wheel door covers were closed anyway, so I am not sure you can see them anyway. I know model photo’s I’ve seen they are open but most of the references I’ve seen those doors are closed.
rossjr has a valid point. There was a post on one of the forums I visit and this fellow stated his father worked on F51’s in Korea. He stated that the only time the inner gear doors were lowered was when maintainance was performed. They did not bleed down as is the common perception and he felt the models with them down were inaccurate. Since I read that I have paid attention to P51 photos and I would agree, in most cases the flaps are dropped but not the inner gear doors. Others may have more information though. Joe
A few years ago, I attended an airshow where 3 P-51D’s, a B17G and B24J flew in and landed. The Liberator made a solo low level pass over the runway, and man was she fast. I filmed the planes as they landed, showing that the P51 will close the inner doors after the mains are down. I also have footage from the war documentaries showing the same. On takeoff, the Mustang’s inner doors open so the mains can retract. The color I’m not certain, but I believe I have seen them both painted and in natural metal. Hope this helps.