Sextant Connie Flight - Hobart (Tas) - Dunedin (NZ)

[TreeTops]

Finally got a chance to try out the Connie using the sextant gauge, thanks to Stearmandriver's video and posts.
Since purchasing the Connie on the day of release, Saturday was my first chance to really get in more than a quick and dirty flight.
For my first flight using the sextant gauge and me being pretty new to the Connie, I wanted to keep it simple and restricted to 3-4 hours. So it was a quick autostart and then FE controls with default weather. The flight was from Hobart, Tasmania, Australia to Dunedin, New Zealand.
Being that the entire west coast of the south island of NZ is high mountains, the decision was made to use the sextant to position the aircraft to the south of the mountains and make landfall beyond where is was much lower elevations which turned out to be Invercargill.
Before the flight I was concerned about always trying to correct the course to particular points along the flight path. I found once I eased into the use of the sextant that it just wasn't necessary to chase the precision that modern navigation demands. It was enough to know that my position was within 30nm.
So here are my Plan-G and Google workings for the flight.
Something I need to get sorted with the Connie and long flights is the Gyro drift time for 1 degree, which makes it easier to correct during flight.

Thanks again Stearmandriver for the inspiration.

[Stearmandriver]

Nicely done! Glad to see folks trying it out.

Looks like a well-planned and executed flight. It's a weird feeling at first, that level of navigational (in)accuracy, but fun when you hit your target, right?

I'm still thinking I'll video my next longish flight, to bookend that basic tutorial I made about the sextant gauge. Can I ask, were there any phases of the flight where you weren't sure what to do, or how to apply what the sextant was telling you? I'm trying to decide how to structure this next video, and if anything unexpected cropped up for you I'm sure it'll apply to others as well, so I'll work it in.

Thanks!

[TreeTops]

Thanks mate. I reflew this run yesterday because in all the excitement of getting comfortable with the Connie and using the sextant I forgot to record distance run along with my half hourly situation numbers. So now I have numbers for a max load Connie at every 5000 up to 20000 feet and then every half hour in cruise and the same down for every gauge on the FE panel and Nav chart.
Time and distance to TOC, cruise speed, time and distance from TOD, fuel consumption etc.
I need all this information to plan future flights and fuel requirements.
I landed with about 1200 gallons but hopefully the maintainance crew won't clobber me for it. Both landings got applause so that's something I suppose. I did allow for hold and divert fuel but the total ended up being too much.
Hopefully for future flights my fuel will fall inside the 900 gallon maximum window without running dry.

I went back and checked your video this morning because I had forgotten how to set the elevation. Use the course knob on the sextant!!! So now that's sorted.

I guess for the next video 2 things in particular I would like to see is how to use the actual sun and stars charts for plotting, and how you estimate your planned waypoints. I just plotted a TOC point and then once I had known cruise speed I plotted a half hour along the path, so after every half hour fix, I planned to fly to the next half hour point correcting course to get back on the path
If you want to, setting the FE panel manually in cruise to maximise performance would be helpful. I fly the B377 completely manual but I haven't put enough hours into the Connie as yet to run manual but that will come soon enough. Now that I am becoming familiar with the basic operation, it's time to re-read the manual and pick up the finer points of operation this beautiful plane.

[TreeTops]

Re-reading the manual I see I was just using the SHIFT 2 cruise recommendation of 2200 RPM and 140 BMEP, where the manual Power Settings chart shows I was pushing it too hard and should have been at 2080 RPM and 125 BMEP. This would explain why my cost per mile for both trips was 0.56 and 0.58 instead of some of the lower numbers I have seen.
I recorded 39 mins and 136 nm with about 155 KIAS average at 2300 RPM and 145 BMEP, so the recommended 161 KIAS with 102nm and 34 mins looks to be in the ball park. Something else to aim for.
I also see that I shouldn't be above 14000ft until the plane is 84000lbs. Which raises the question, what aircraft weight is used for the Climb data that it can go straight up to 21000 ft ?
Bit by bit I will get this plane sorted.

[Stearmandriver]

Excellent, thanks. I'll talk about using actual star positions in the beginning when explaining my dead reckoning a bit.

I've actually been using 1 hour checkpoints, but I've been thinking that with the extra speed of the Connie more frequent checks might be smart. I started doing this stuff with the C47 and hourly checks worked well, but you cover a lot more miles in that hour in the Connie. But then, hourly checks worked ok on the last flight I did, so... trial and error I guess

I have been planning checkpoints the same way as you though, just by time. Over land I would tend to plan them to coincide with identifiable ground features or radio bearings, but out in the open ocean time is all you've got.

[TreeTops]

I was using half hour shots just to for fun really. Hourly should be fine, although the Connie covers about 230nm in that time. The problem with such a long time between waypoints is the magnetic variation, particularly in the higher latitudes (+-40). Using my flight plan from Hobart to Dunedin with hourly plots, the headings change beginning with 97, 90, 84, 77, so the drift off course just because of magnetic variation in the higher latitudes is significant.
I also was taking notice of the gyroscopic drift on the last flight and it works out to be a about 1 degree left for every 5 minutes. ie the autopilot drifts left of track over time.
So for accurate tracking, every 15 minutes adjust 1 degree right of heading so that it travels 5 minutes right of track, 5 minutes along track, and 5 minutes left of track, then correct 3 degrees right.

[TreeTops]

I also read in the manual that its not more than 900 USG in either outboard tank. I had it in my head from the initial speed read that it was not more than 900 USG total fuel, so that sure makes it easier to carrier more fuel across long distances.
So many things to get into my head. Its a matter of read, fly read, adjust the way I fly, read, adjust some more.
Best advice I tell myself with complex aircraft is, just fly the thing and it will help when I read the manual again.

[ApacheHunter]

Thanks for sharing! I think this kind of navigation is very interesting and adds a lot to the immersion of flying a 1940's airliner.

Glad to see folks trying it out.

Even though I've stayed quiet for a while, I've been trying this as well since your first post about it. First in the C-47 (Manfred Jahn, Jan Visser et al.), later in the Connie. I didn't keep a full logbook consisting of the Captain's log, screenshots, etc. I still do have my Google Earth plot, though:



This flight is part of my Amsterdam-Batavia route (KLM, 1947) I started when the Connie was released. This is on the way back to the Netherlands and the first 'real' flight I used celestial navigation on. It felt very realistic and rewarding! I didn't fly using real weather, though (or any weather, for that matter). I wanted to see how I'd perform using only the sextant to get location estimates. I think I can't complain, although I was a little fast!

[TreeTops]

Fantastic to see you enjoying this also. Regards going too fast, I think planning fixes along the route expecting to be overhead at a certain time is not the point. Wind speed and direction at altitude would not have been known when the Connie flew, only by pireps probably. The first point is something to aim for, then once an actual plot has been marked at say the 1 hour point, wind information would be coming clearer. Better to fly the plane at it desired speed, be it for speed or for economy.
Keep posting and we will grow our little group .

[Stearmandriver]

Yup that's how I look at it too. Speed and fuel burn checks are important to make sure your planned arrival time and fuel are remaining accurate. If you're fast and under burn, that's all good - just take the free speed and fuel into consideration. If you're late and grossly over burn, that could be a problem.

Judy keep track of your actual groundspeed so, when you reach a phase of flight where you need to know your GS relatively accurately for planing, you'll have it. This would usually be planing your arrival (you need to know when you're getting close) or especially when planning to intercept an LOP for a landfall procedure.

Just measure the distance between the two most recent fixes (you should have recorded the times you took each) and run a quick time/speed/distance calculation, and you'll have a pretty good recent GS estimate. You can use that to estimate your arrival time at either destination or LOP intercept.

[Stearmandriver]

Thanks for sharing! I think this kind of navigation is very interesting and adds a lot to the immersion of flying a 1940's airliner.

This flight is part of my Amsterdam-Batavia route (KLM, 1947) I started when the Connie was released. This is on the way back to the Netherlands and the first 'real' flight I used celestial navigation on. It felt very realistic and rewarding! I didn't fly using real weather, though (or any weather, for that matter). I wanted to see how I'd perform using only the sextant to get location estimates. I think I can't complain, although I was a little fast!

Nicely done btw. Thanks for sharing yours also!

I like your use of range "rings" to calculate each checkpoint, as well as your inclusion of rounded coordinates in the label of each point. I'd been measuring with the line tool and having to right - click each point for the properties whenever I needed the coordinates. These are two simple time - saving techniques, exactly the type of thing I was hoping would surface as we started sharing stories.

[ApacheHunter]

Yeah, I like the rings too! I found out Google Earth Pro is free nowadays, so I downloaded it and started using the rings. They're also quite handy to measure all sorts of things in-flight, although that's not visible in the picture. I have to admit I added the coordinates labels afterwards, just before posting the picture on the forums, but I figured I'd use them for future flights!

There's one thing (so far) that's not quite clear to me yet regarding celestial navigation: the landfall procedure and intercepting the sun LOP for arrival.

[TreeTops]

Google Earth Pro is awesome. More features than the old standard version. The circles are very handy when plotting routes. They have even removed the requirement for a password now with the latest download.

So my latest drama to contend with this week. A few weeks ago I had to reinstall w10 because of blue screen problems I couldn't recover from.
I thought I had everything sorted this last weekend but alas an ugly gremlin raised it head the last two days. Driver Power State Failure. ie USB devices being put to sleep.
So after 2 successful flights from Hobart to Dunedin, yesterday I carefully planned a flight from Broome to Mt Isa, Australia. About an hour into the flight BAM, blue screen. ARRHH
Went to bed with the plan to do an extreme range flight from Perth to Diego Garcia of 2850nm. Wind seemed to be favourable down at 5000ft until about 2/3's into the flight. Played around with PFPX all afternoon getting a suitable flight together.
This morning 2 hours into the flight, bang, blue screen. Walk away from the computer before doing any damage....
So after spending the morning sorting out the USB power stuff I tried a flight from Dubrovnik-Innsbruck. The flight was going so well up at FL160 nearing RTT for Innsbruck I decided I needed more hours in the flight to prove the blue screen problem had been solved. I decided to press on to Onslow which made it a 1000+ nm flight.
Everything went perfectly until about 10-15nm from ESSA and I had a memory full failure. AHHH. At least it wasn't a power driver state failure.
So now I am confident of doing long flights, just not into a heavy airport like Orbx Onslow.

[ApacheHunter]

Problems like that are so annoying! I hope you'll be able to sort them out soon.

Anyway: did I just spot a GPS unit in your Connie?!

[TreeTops]

Yes it's the 650. This flight was nothing to do with navigation, but all to do with hours in the air to prove the usb problem fixed.
When the sextant comes out, the 650 goes off.