Hi there,
in the meantime I looked more closely at the
Access Arms at the Tower in order to count the local lamps. In addition I have here a suitable visual attunement from the preparatory phase to the
STS-6.
Source: retrospaceimages.com (STS-6)These are the
Orbiter Access Arm (OAA) with the White Room,
the
Oxygen Vent Arm (OVA) with the Beanie Cap,
and the
Gaseous Hydrogen Vent Arm (HVA), also called
Intertank Access Arm (IAA).
For image analysis, I have partly fall back on old pictures from the early years of the shuttle program, which comes in part from the work-up phase of the
Pad 39B. These are scans from the photo album of a friend who worked there and has experienced a lot.

And so directly to the
OAA, which can be seen on this old picture before mounting on the pad 39B. Okay, the quality is not great, but these images are a significant historical fundus, which I do not want to miss, as these images are really real-time documents from the early years to the Shuttle STS-6 around. And much more important than image quality is, that one can exactly recognize the
9 lamps anyway.
Source: NasaSpaceflight.com (J. MacLaren)Here is a photo of the STS-6, on which the former lamps are beautiful to see.
Source: retrospaceimages.com (STS-6)As I said, the lamps saw later completely different, just more modern, and were not mounted in gait center but on the side (left). BTW, there were at that time much more lights than in later years.

And so now to the
OVA, in this picture still without
Beanie Cap, I have viewed from several perspectives before the count of the lamps.
Source: NasaSpaceflight.com (J. MacLaren)This arm has six standard lamps (1-6) and two smaller spotlights (7/8), so a total of
8 lamps.
Source: NasaSpaceflight.com (J. MacLaren)Missing only the
HVA, that is a real steel frame monster solely due to its size, which you can see in this picture, but from a later mission.
The frame structure consists essentially of three parts:
The huge multistory
Front building is firmly connected with the Tower, but had only the top three floors during
STS-6, the lower small 4th floor was retrofitted later.
Source: NASAThe actual
Swing arm allows mating of the
External tank (ET) umbilicals as well as contingency access to the ET intertank compartment, which rotated 210° to its extended position at the ET and was connected with this. The
Elephant’s Trunk called umbilical vent line provides continuous venting of the external tank during and after loading of the volatile liquid hydrogen. The vent line is disconnected from the ET at first motion of the stack and retracts vertically downward to a stored position.
And for the lamps count it now goes back to
STS-6. And the following image at first one can see these
13 lamps which are directly mounted on the outside of the Front building.

Source: retrospaceimages.com (STS-6)But that's not all, because in this picture of the
STS-1 with connected Swing arm and Trunk (white) one can immediately recognize in front of the ET a lamp pole with
4 lamps, I hope so.
Source: NASAThis results ultimately a total number of
34 lamps for the three Access arms, but this number is not exhaustive.

And so I want it to stop there for now and wish you a nice Sunday.
