Yes, the Navigator used those windows to locate a suitable star to "shoot", which made it easier for him to find it with the sextant. He then recorded its elevation, crosschecked his tables & the clock, and came up with a "line of position" to draw on the chart. Three such lines, from different stars, would form a triangle (the smaller the better), enclosing our position.

 

I see. I guess the same could be said from some lockheed aircraft, Electra & C-130. I guess it was an "era" thingy!

 

In my experience, the Navigator determined from tables, position, and time of day which bodies would be viewable, which would be most useful (based on direction of our course), and approximately where they would be. So, when it was time to shoot, he had the boom operator (in the tanker) or the other navigator (in the other -135) set an azimuth and elevation in the sextant before it was even extended. Based on those "precomps" he would have the sextant pointed very close to the star to begin with. Once the sextant was extended and turned to the proper azimuth, it was usually just a matter of seconds until he could find the body and fine-tune the settings.

Unless the body was very high in the sky, the windows couldn't have helped "spot" the body to begin with. I suppose it could have been a quick way of determining whether there were clouds above.






.

 

You could see a fairly large section of sky from each of the two windows if you were close to them. I agree about the "precomp", and remember the Nav craning his head around the windows when a star stubbornly refused to appear in the sextant. As you suggest, he was probably checking whether the sky was clear in that area and to see if the star was visible at least approximately where it should be. If not, he'd try another star or re-check his figures.

 

Umm, they used to.

Each one of my squadron's 16 KC-135R's has two old window "areas" next to the sextant port in the roof of the central cockpit area. The windows have been removed and the holes have been blocked off.

Many years ago, but less than 30 years ago, one of these windows on some KC-135 blew out, and an unlucky boom operator was killed in an extremely gruesome fashion when he filled the hole with his head and upper torso. Our now retired chief boom knew the gentleman who lost his life.

I can post a pic of the sealed off windows if you need proof of their prior existence. It's my understanding that the windows provided the nav with a little "SA" as he used the the sextant....so he could see a broader portion of the sky than just the very limited view through the instrument itself.

The sextant port is now occasionally used as a receptacle for a rather humorously shaped satphone antenna (on Block 30 jets only since Block 40 jets have a dedicated Satcom system.

 

The original B-707 climbed out at such a shallow deck angle the windows were used to scan for traffic while in the climb.

 

Alright. Tony C comes through with the real facts. I've been itching to post this stuff, but thought I ought to read through the rest of the thread to see if someone had the real story. While I don't know what super early production 135s had in the way of extra windows, after 8 years and over 4000 hours on various 135 and E-3 models, Tony has his facts straight on the eyebrow windows and sextant port. And like others have mentioned, I've flown several 727s that had sextant ports, usually -100 models, built before omega and ins were available.

 

Good luck convincing the I-phone generation (GPS on their phones) that you could actually navigate by observing celestial objects.

Scoop

 

This brought back some memories... A while back when I was flying for HootersAir I remember one of the cute and really young girls ask me "so, how do you know which way to go?" She added "there are so many buttons here?"

We were at the gate (MYR) and before I had a chance to respond the captain said "oh, we use celestial navigation, we simply follow the stars and the 'polar star' in particular."

He saw my huh? expression but soon I started playing along. He said, "you have to look at this telescope here and point it at the star, then you adjust the "star angle" and the computer calculates the course you have to fly. You can try to find a star right now if you want but it's hard to find them during daylight hours." So she leaned forward and the captain's grin got much more obvious; ok, I enjoyed it too... )

She closed one eye while she tried to look into this "telescope" with the other eye... Then she said "yeah, I think I see it!" At that point I turned my face away pretending I was on my cell phone because I had tears in my eyes...

She was staring at the lens of the reading light right above his seat! Oh, sweet memories... LOL

I don't think she ever knew it was just a prank and I didn't want to spoil her new discovery...