IAS, TAS, and ground speed (GS)

[mongoose]

So, moving this away from https://sim-outhouse.org/sohforums/threads/low-speed-trim-for-ju88.163474/
The question WRT CFS3 is of course what speed is what, The ac gauges will show IAS, while 'z' will show TAS; however neither will indicate GS which is the vector sum of TAS and wind velocity.
Now I assume the navigator would have to plot that by some form of reckoning , either of ground location or using the stars; Dan can but in here.
In CFS3, using the 'm' for the map, one can fix ground location in flight, but I assume within the mission builder, any wp times won't reflect GS, but only TAS? This does complicate planning somewhat, but I assume that was also true in real life, where wind speeds were often not known in advance at high level.
So far, I have not played around too much with setting wind speeds at various sectors, which would add extra realism, but i feel that I should maybe try. I just don't know how having fixed wps in the missions would deal with that, as opposed to not having wps, but just real navigation points. Maybe it's too complicated for CFS3 and most players; it's not Prepar3D after all.

 

[gecko]

I'm not sure if mission builder will factor in the weather file's wind parameters into the times it gives or not. Worth a try setting up a mission with a no wind weather file called for, noting the waypoint times, and then changing the weather file to something that will give a headwind or tailwind, and seeing if the times change.

Now, for how it works in real life (pre-GPS). It starts with setting out your plan. This is most easily done based on known TAS of your aircraft at a particular power setting, altitude, and air temperature. I have not seen the kind of data in the WWII fighter manuals I have looked at, but maybe the bombers have some more detail. I also get the impression that pilot manuals for US WWII aircraft have more detailed performance charts. In any case, I'm sure everyone had this data in some form even if it wasn't included in the manuals. So you lay out your course, note your distances and headings between waypoints, and divide your distance by your TAS to get the time between waypoints for each leg.

Then you need to factor in the wind forecast or observations. I know they had some of this data in WWII, but I doubt it was nearly as complete or accurate as what pilots have access to now. Now there is software that interpolates data from different locations to give you a prediction of winds along your route and it's influence on your times, but before that you just did your best to figure it out manually. A pilot would take the expected wind speed and direction, and use a "whizz-wheel" to calculate the resulting ground speed and heading correction required. And it works quite well. When I trained, though the plane was equipped with GPS, I wasn't allowed to use it, and had to do everything manually with a map with my route plotted on it, compass, and stopwatch. With a detailed plan and disciplined tracking of time and maintaining heading, I found I could routinely (though definitely not always) pass a waypoint within 15 seconds of when I expected to.

Now, when you are actually flying the route, things can change, so you have to keep track of your progress, note deviation from your plan, determine what caused it, and make the appropriate adjustments.The above is all compass and stopwatch dead reckoning. You make corrections based on pilotage - locating your position visually on a map. You can note if your planned heading is keeping you on course, or if the wind is different than forecast and you are getting blown off course and need to adjust your heading to correct it. You can note the time it takes to reach your waypoint, and see if it corresponds to your plan, or if you have a greater headwind or tailwind than you expected. You can the adjust your times accordingly.

The easiest way would be to make your first waypoint a known, easily identifiable point near the point of departure, note your time crossing it, and set all of your ETAs at subsequent waypoints based on that. Frequent checks early on can help establish the accuracy of your calculations and allow you to make any needed adjustments early. Wind may shift later in the flight, and you have to catch it if it does, but at least you know you started out with information you were able to verify.

This is of course all much easier to do during daylight than at night with a blackout enforced. Bad weather can also prevent you from being able to see to make corrections.You break out of the clouds to find that you are not where you expected to be, and now have to figure out where the heck the winds have taken you. And the longer your flight and the longer you have to go between opportunities to fix your position, the more susceptible you are to getting off course. This explains Bomber Command's abysmal results in even finding their targets early in the war before electronic navigation became the norm.

 

[gecko]

Some thoughts on simulating all of this:

When I try to add something to improve realism and add challenge, I try to stick to the principle of not adding difficulty without also providing the tools or sensory feedback the pilot would have had to be able to deal with the challenge. More realistic navigation is something I'd love to see, and something I think is achievable. But, we are currently seriously lacking in tools needed to do it well. Better maps, better aircraft performance data, accurate fuel consumption, materials to help a pilot learn how to actually use the information available. And it could be simplified in multi-crew aircraft since most of them carried a dedicated navigator who did all the work and gave instruction to the pilot. Implementing all of this I think is doable, and I'd love to see it. In WWII, my grandfather was a navigator on PBMs in the Caribbean, and my great uncle was a navigator on B-17s over Europe, so it has some personal interest for me. I think the key is in adding the supporting tools, otherwise you are just creating an exercise in frustration.

As an aside, this is my big issue with IL-2 Great Battles and why I will never be able to enjoy it. After supposedly implementing complex engine management, they made engine damage dependent upon the time spent running the engine at a given power setting instead of the much more relevant issue of engine temperature. Those two things are not directly related in real life and why cockpits have engine temp gauges and not a bunch of timers in the cockpit. So in IL-2, the tools a pilot would have used to manage the engine (the temp gauges) are made largely irrelevant by the completely unrealistic engine timer system, and thus the pilot is robbed of the effective and realistic means of keeping the engine healthy. I can only assume this was done in the name of "balance" for multiplayer lobby, but for me it took what would have been a cool sim and made it completely unplayable. Ok, rant over.

 

[mongoose]

The issue in combat sims is always what most players want; often just quick action shoot 'em ups missions or QC, as opposed to Prepar3D etc.. If there was much more realism in a multi crew aircraft, it would be difficult for a single player to deal with all those tasks; pilot, co pilot, navigator/bombader, never mind gunners. As far as I can see, use of 'z' and 'm' are the best we can do, with maybe timing over fixed 'm' positions, and using 'pause' if necessary, to work stuff out! There was a stage in the past when I would make a mission with wps, and then use the data from those to make one with wps removed and navigational details provided as a 'readme'; I have to see if I still have any, but IIRC, not many would want to go through that effort. I might try a few in TOW II, especially missions where wind was a big factor. IIRC Nuremberg in March 1944 was one of those occasions.
We do now have a workable 'Oboe' thanks to Steve in the AIradar app, and Joost and I have been doing our best to make a sort of H2S work around, which is something. Ted and I have also been looking at navigational aids for NJ aircraft as well.
What we can at least do is some engine management WRT to RPMs, alt, and TAS, to get good trim at least, instead of relying on Ctrl Shift A, which I don't think works that well. I am looking at making tables for results in some ac, starting with the JU88s of Ted, and should look at Lancs, etc as well.