Nose windows

Little seems to have been written about the variability of the windows in the forward fuselage. The overall shape and structure of the forward fuselage, from bulkhead 6 forward, seems to have changed very little over the rather long life of the B-17, apart from the addition of the top turret in the B-17E, which has otherwise described as having a new aft fuselage grafted on to the front of a B-17D. Changes in the top turret and the dorsal gun mounting are documented on another page. And starting in the middle of B-17F production the astrodome supplemented or supplanted overhead windows in the front compartment.

While the placement of the windows in the nose seems to have changed little over time, there does seem to have been some variation in sizes. The windows in the B-17Cs on the flightline and those in the B-17G seem to be in the same places and, typically, about the same size.

At some undocumented point in time, B-17s started appearing with larger windows in forward fuselage, almost always associated with machine-gun mounts. Presumably this was done to provide the navigator and bombardier with better vision when manning their guns.
This B-17F with enlarged windows looks to have been modified in the field,
but a virtually identical arrangement in the nose of Damifino suggests that the arrangement was either a factory application, a mod-center modification, or a field-mod kit.

The enlarged windows on Hells Angels and Yankee Doodle, on the nose guns page, also give the appearance of field mods, especially since both planes are almost certainly B-17Es. Another picture showing the right side of the nose of Hell's Angels appears in "What's In A Name?" [ PDF, 13.3 MiB ] , [ HTML ] shows that it had the large front right window, too. A detail of the nose of Old Bill in the same article indicates that it had the large front right window.

The thought that the mod was incorporated into production is supported by a Boeing ad, "Flight without wings" shows a unfinished fuselages with the same enlarged-window arrangement. These seem to be B-17F airframes under construction.

While all of the B-17E and B-17F examples seem to have the same arrangement — front window on the right side, second window on the left — B-17Gs seem to have reversed that arrangement, as shown on nose guns page.

Whatever the rules were, they do not seem to have been universal, or very consistent. The Pilot Training Manual has a photo of a B-17F with large windows, but the 3-view shows small windows; various illustrations show both versions of B-17Fs, while all of the illustrations of B-17G show small windows; the Bail Out diagram shows an -F with large second window on the right and the machine gun mounted in the (small) front window on that side. A photo in the manual of a crash-landed B-17F shows a large second right window with machine gun mount.

Other photos that show details of the nose window installations include:

This listing is not comprehensive — there are many more images that show window locations, especially of the B-17E and B-17F configurations with small windows. It does include samples of each configuration that I have pictures of and most of the images that show clearly a large window or built-out gun mount.

Nose

The nose of the B-17 changed quite a lot during the life of the type, apart from the additions made in the field. The biggest change happened during the transition from B-17E to B-17F production:

The "all-glass" nose from Vega quickly became the standard for all future production. The situation is not simple, however. Photos in Plexiglas® ads — show what appears to be a flanged seam, but may be an overlapping seam, on the nose bubble

detail from "On the nose. . . ."

or the vertical seam that appears in this photo of a bombardier at work, which also shows seams that converge from 4 o'clock and 8 o'clock,

Compare the visibility and working room of the B-17F on the left and the B-17E on the right.

A Pittsburgh Plate Glass ad does not appear to show seams on a B-17G,
"For precision bombing ... precision plate glass"


but a news clip production line photo does:

Note that the seam here seems to be horizontal, placed at the top of the plate-glass bombsighting window, rather than coming from 4 and 8 o'clock as in the photo above.

At any rate, the allusions to a "one-piece" nose, or "bubble" on the -F and -G models seem a bit overstated, even though the contrast of the frameless nose with those of the earlier B-17 models, or with most other bombers of the period, might make it appear that way to a casual observer.

None of my references mentions any of the variation in greenhouse glazing that we can see in these photos. Since there were no significant changes in the profile of the nose section (the chin turret was grafted in) between the B-17F and B-17G and the shape of the section at the forward end of the fuselage seems not to have changed between the -E and -F, it is likely that these different configurations were interchangeable and any nose might be seen on any model of B-17 after it had had nose damage repaired.

A nose-on shot of a Vega-built plane shows the startling clarity and surprising lack of distortion of the "all-glass" nose:

Images that show details of the various nose structures include: